Getting rid of SQLValueFunction

From 8d1a424e44f46f3107a6f0f066da22c19e4e4f3b Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Fri, 21 Oct 2022 14:06:03 +0900
Subject: [PATCH v2 1/2] Remove from SQLValueFunction all the entries using
 "name" as return type

This commit changes six SQL keywords to use COERCE_SQL_SYNTAX rather
than SQLValueFunction:
- CURRENT_ROLE
- CURRENT_USER
- USER
- SESSION_USER
- CURRENT_CATALOG
- CURRENT_SCHEMA
Among the six, "user", "current_role" and "current_catalog" require
specific SQL functions to allow ruleutils.c to map them to the SQL
keywords these require when using COERCE_SQL_SYNTAX.  Having
pg_proc.proname match with the keyword ensures that the compatibility
remains the same when projecting any of these keywords in a FROM clause
to an attribute name when an alias is not specified.  Tests are added to
make sure that the mapping happens from the SQL keyword is correct,
using a view defition that feeds on these keywords in one of the tests
introduced by 40c24bf (both in a SELECT clause and when using each
keyword in a FROM clause).

SQLValueFunction is reduced to half its contents after this change,
simplifying its logic a bit as there is no need to enforce a C collation
anymore.  I have made a few performance tests, with a million-ish calls
to these keywords without seeing a difference in run-time or in perf
profiles.  The remaining SQLValueFunctions relate to timestamps.

Bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/catversion.h          |  2 +-
 src/include/catalog/pg_proc.dat           |  9 ++++++
 src/include/nodes/primnodes.h             |  8 +----
 src/backend/executor/execExprInterp.c     | 27 -----------------
 src/backend/nodes/nodeFuncs.c             | 11 ++-----
 src/backend/parser/gram.y                 | 30 ++++++++++++++----
 src/backend/parser/parse_expr.c           |  8 -----
 src/backend/parser/parse_target.c         | 18 -----------
 src/backend/utils/adt/ruleutils.c         | 36 +++++++++++-----------
 src/test/regress/expected/create_view.out | 37 +++++++++++++++++++++--
 src/test/regress/sql/create_view.sql      | 15 ++++++++-
 11 files changed, 105 insertions(+), 96 deletions(-)

diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 4c930c189b..032a429345 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202210141
+#define CATALOG_VERSION_NO	202210211
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 62a5b8e655..241366fc8e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1505,6 +1505,15 @@
 { oid => '745', descr => 'current user name',
   proname => 'current_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'current_user' },
+{ oid => '9695', descr => 'current role name',
+  proname => 'current_role', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_user' },
+{ oid => '9696', descr => 'user name',
+  proname => 'user', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_user' },
+{ oid => '9697', descr => 'name of the current database',
+  proname => 'current_catalog', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_database' },
 { oid => '746', descr => 'session user name',
   proname => 'session_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'session_user' },
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index 40661334bb..e818231e15 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1313,13 +1313,7 @@ typedef enum SQLValueFunctionOp
 	SVFOP_LOCALTIME,
 	SVFOP_LOCALTIME_N,
 	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N,
-	SVFOP_CURRENT_ROLE,
-	SVFOP_CURRENT_USER,
-	SVFOP_USER,
-	SVFOP_SESSION_USER,
-	SVFOP_CURRENT_CATALOG,
-	SVFOP_CURRENT_SCHEMA
+	SVFOP_LOCALTIMESTAMP_N
 } SQLValueFunctionOp;
 
 typedef struct SQLValueFunction
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 9b9bbf00a9..6ebf5c287e 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -2495,15 +2495,10 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 void
 ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
 {
-	LOCAL_FCINFO(fcinfo, 0);
 	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
 
 	*op->resnull = false;
 
-	/*
-	 * Note: current_schema() can return NULL.  current_user() etc currently
-	 * cannot, but might as well code those cases the same way for safety.
-	 */
 	switch (svf->op)
 	{
 		case SVFOP_CURRENT_DATE:
@@ -2525,28 +2520,6 @@ ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
 		case SVFOP_LOCALTIMESTAMP_N:
 			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
 			break;
-		case SVFOP_CURRENT_ROLE:
-		case SVFOP_CURRENT_USER:
-		case SVFOP_USER:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_user(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_SESSION_USER:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = session_user(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_CURRENT_CATALOG:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_database(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_CURRENT_SCHEMA:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_schema(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
 	}
 }
 
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 0a7b22f97e..2585a3175c 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -917,11 +917,8 @@ exprCollation(const Node *expr)
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
 		case T_SQLValueFunction:
-			/* Returns either NAME or a non-collatable type */
-			if (((const SQLValueFunction *) expr)->type == NAMEOID)
-				coll = C_COLLATION_OID;
-			else
-				coll = InvalidOid;
+			/* Returns a non-collatable type */
+			coll = InvalidOid;
 			break;
 		case T_XmlExpr:
 
@@ -1144,9 +1141,7 @@ exprSetCollation(Node *expr, Oid collation)
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
 		case T_SQLValueFunction:
-			Assert((((SQLValueFunction *) expr)->type == NAMEOID) ?
-				   (collation == C_COLLATION_OID) :
-				   (collation == InvalidOid));
+			Assert(collation == InvalidOid);
 			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 737bd2d06d..605e9ec096 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -15229,15 +15229,24 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_ROLE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_ROLE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_role"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| SESSION_USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_SESSION_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("session_user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| SYSTEM_USER
 				{
@@ -15248,15 +15257,24 @@ func_expr_common_subexpr:
 				}
 			| USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_CATALOG
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_CATALOG, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_catalog"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_SCHEMA
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_SCHEMA, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_schema"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CAST '(' a_expr AS Typename ')'
 				{ $$ = makeTypeCast($3, $5, @1); }
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 7aaf1c673f..9bde33b407 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -2231,14 +2231,6 @@ transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
 			svf->type = TIMESTAMPOID;
 			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
 			break;
-		case SVFOP_CURRENT_ROLE:
-		case SVFOP_CURRENT_USER:
-		case SVFOP_USER:
-		case SVFOP_SESSION_USER:
-		case SVFOP_CURRENT_CATALOG:
-		case SVFOP_CURRENT_SCHEMA:
-			svf->type = NAMEOID;
-			break;
 	}
 
 	return (Node *) svf;
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index bd8057bc3e..f54591a987 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1895,24 +1895,6 @@ FigureColnameInternal(Node *node, char **name)
 				case SVFOP_LOCALTIMESTAMP_N:
 					*name = "localtimestamp";
 					return 2;
-				case SVFOP_CURRENT_ROLE:
-					*name = "current_role";
-					return 2;
-				case SVFOP_CURRENT_USER:
-					*name = "current_user";
-					return 2;
-				case SVFOP_USER:
-					*name = "user";
-					return 2;
-				case SVFOP_SESSION_USER:
-					*name = "session_user";
-					return 2;
-				case SVFOP_CURRENT_CATALOG:
-					*name = "current_catalog";
-					return 2;
-				case SVFOP_CURRENT_SCHEMA:
-					*name = "current_schema";
-					return 2;
 			}
 			break;
 		case T_XmlExpr:
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 70d723e80c..f95289f11c 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -9199,24 +9199,6 @@ get_rule_expr(Node *node, deparse_context *context,
 						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
 										 svf->typmod);
 						break;
-					case SVFOP_CURRENT_ROLE:
-						appendStringInfoString(buf, "CURRENT_ROLE");
-						break;
-					case SVFOP_CURRENT_USER:
-						appendStringInfoString(buf, "CURRENT_USER");
-						break;
-					case SVFOP_USER:
-						appendStringInfoString(buf, "USER");
-						break;
-					case SVFOP_SESSION_USER:
-						appendStringInfoString(buf, "SESSION_USER");
-						break;
-					case SVFOP_CURRENT_CATALOG:
-						appendStringInfoString(buf, "CURRENT_CATALOG");
-						break;
-					case SVFOP_CURRENT_SCHEMA:
-						appendStringInfoString(buf, "CURRENT_SCHEMA");
-						break;
 				}
 			}
 			break;
@@ -10318,6 +10300,24 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoChar(buf, ')');
 			return true;
 
+		case F_CURRENT_CATALOG:
+			appendStringInfoString(buf, "CURRENT_CATALOG");
+			return true;
+		case F_CURRENT_ROLE:
+			appendStringInfoString(buf, "CURRENT_ROLE");
+			return true;
+		case F_CURRENT_SCHEMA:
+			appendStringInfoString(buf, "CURRENT_SCHEMA");
+			return true;
+		case F_CURRENT_USER:
+			appendStringInfoString(buf, "CURRENT_USER");
+			return true;
+		case F_USER:
+			appendStringInfoString(buf, "USER");
+			return true;
+		case F_SESSION_USER:
+			appendStringInfoString(buf, "SESSION_USER");
+			return true;
 		case F_SYSTEM_USER:
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
diff --git a/src/test/regress/expected/create_view.out b/src/test/regress/expected/create_view.out
index bf4ff30d86..e7f7323113 100644
--- a/src/test/regress/expected/create_view.out
+++ b/src/test/regress/expected/create_view.out
@@ -1941,7 +1941,20 @@ select
   trim(E'\\000'::bytea from E'\\000Tom\\000'::bytea) as btb,
   trim(leading E'\\000'::bytea from E'\\000Tom\\000'::bytea) as ltb,
   trim(trailing E'\\000'::bytea from E'\\000Tom\\000'::bytea) as rtb,
-  SYSTEM_USER as su;
+  CURRENT_CATALOG as ca,
+  (select * from CURRENT_CATALOG) as ca2,
+  CURRENT_ROLE as cr,
+  (select * from CURRENT_ROLE) as cr2,
+  CURRENT_SCHEMA as cs,
+  (select * from CURRENT_SCHEMA) as cs2,
+  CURRENT_USER as cu,
+  (select * from CURRENT_USER) as cu2,
+  USER as us,
+  (select * from USER) as us2,
+  SESSION_USER seu,
+  (select * from SESSION_USER) as seu2,
+  SYSTEM_USER as su,
+  (select * from SYSTEM_USER) as su2;
 select pg_get_viewdef('tt201v', true);
                                         pg_get_viewdef                                         
 -----------------------------------------------------------------------------------------------
@@ -1963,7 +1976,27 @@ select pg_get_viewdef('tt201v', true);
      TRIM(BOTH '\x00'::bytea FROM '\x00546f6d00'::bytea) AS btb,                              +
      TRIM(LEADING '\x00'::bytea FROM '\x00546f6d00'::bytea) AS ltb,                           +
      TRIM(TRAILING '\x00'::bytea FROM '\x00546f6d00'::bytea) AS rtb,                          +
-     SYSTEM_USER AS su;
+     CURRENT_CATALOG AS ca,                                                                   +
+     ( SELECT "current_catalog"."current_catalog"                                             +
+            FROM CURRENT_CATALOG "current_catalog"("current_catalog")) AS ca2,                +
+     CURRENT_ROLE AS cr,                                                                      +
+     ( SELECT "current_role"."current_role"                                                   +
+            FROM CURRENT_ROLE "current_role"("current_role")) AS cr2,                         +
+     CURRENT_SCHEMA AS cs,                                                                    +
+     ( SELECT "current_schema"."current_schema"                                               +
+            FROM CURRENT_SCHEMA "current_schema"("current_schema")) AS cs2,                   +
+     CURRENT_USER AS cu,                                                                      +
+     ( SELECT "current_user"."current_user"                                                   +
+            FROM CURRENT_USER "current_user"("current_user")) AS cu2,                         +
+     USER AS us,                                                                              +
+     ( SELECT "user"."user"                                                                   +
+            FROM USER "user"("user")) AS us2,                                                 +
+     SESSION_USER AS seu,                                                                     +
+     ( SELECT "session_user"."session_user"                                                   +
+            FROM SESSION_USER "session_user"("session_user")) AS seu2,                        +
+     SYSTEM_USER AS su,                                                                       +
+     ( SELECT "system_user"."system_user"                                                     +
+            FROM SYSTEM_USER "system_user"("system_user")) AS su2;
 (1 row)
 
 -- corner cases with empty join conditions
diff --git a/src/test/regress/sql/create_view.sql b/src/test/regress/sql/create_view.sql
index 913b4ee460..04fc0ba35e 100644
--- a/src/test/regress/sql/create_view.sql
+++ b/src/test/regress/sql/create_view.sql
@@ -722,7 +722,20 @@ select
   trim(E'\\000'::bytea from E'\\000Tom\\000'::bytea) as btb,
   trim(leading E'\\000'::bytea from E'\\000Tom\\000'::bytea) as ltb,
   trim(trailing E'\\000'::bytea from E'\\000Tom\\000'::bytea) as rtb,
-  SYSTEM_USER as su;
+  CURRENT_CATALOG as ca,
+  (select * from CURRENT_CATALOG) as ca2,
+  CURRENT_ROLE as cr,
+  (select * from CURRENT_ROLE) as cr2,
+  CURRENT_SCHEMA as cs,
+  (select * from CURRENT_SCHEMA) as cs2,
+  CURRENT_USER as cu,
+  (select * from CURRENT_USER) as cu2,
+  USER as us,
+  (select * from USER) as us2,
+  SESSION_USER seu,
+  (select * from SESSION_USER) as seu2,
+  SYSTEM_USER as su,
+  (select * from SYSTEM_USER) as su2;
 select pg_get_viewdef('tt201v', true);
 
 -- corner cases with empty join conditions
-- 
2.37.2

From 9f5bb5ba425f923ab9286b810594b2c312739ffa Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Fri, 21 Oct 2022 14:19:41 +0900
Subject: [PATCH v2 2/2] Replace SQLValueFunction by direct function calls

This impacts 9 patterns where the SQL grammar takes priority:
- localtime, that can take a typmod.
- localtimestamp, that can take a typmod.
- current_time, that can take a typmod.
- current_timestamp, that can take a typmod.
- current_date.

Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to keep compatibility (when a keyword is specified in a
SELECT or in a FROM clause without an alias), with tests to cover all
that.

XXX: bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/pg_proc.dat           |  15 +++
 src/include/executor/execExpr.h           |   8 --
 src/include/nodes/primnodes.h             |  33 -------
 src/include/utils/date.h                  |   4 -
 src/include/utils/timestamp.h             |   4 -
 src/backend/catalog/system_functions.sql  |  26 ++++++
 src/backend/executor/execExpr.c           |  11 ---
 src/backend/executor/execExprInterp.c     |  46 ---------
 src/backend/jit/llvm/llvmjit_expr.c       |   6 --
 src/backend/jit/llvm/llvmjit_types.c      |   1 -
 src/backend/nodes/nodeFuncs.c             |  27 +-----
 src/backend/optimizer/path/costsize.c     |   1 -
 src/backend/optimizer/util/clauses.c      |  39 ++------
 src/backend/parser/gram.y                 |  59 +++++++-----
 src/backend/parser/parse_expr.c           |  52 -----------
 src/backend/parser/parse_target.c         |  25 -----
 src/backend/utils/adt/date.c              |  81 +++++++++-------
 src/backend/utils/adt/ruleutils.c         | 109 +++++++++++++---------
 src/backend/utils/adt/timestamp.c         |  72 ++++++++------
 src/backend/utils/misc/queryjumble.c      |   9 --
 src/test/regress/expected/create_view.out |  45 +++++++++
 src/test/regress/expected/expressions.out |   2 +-
 src/test/regress/sql/create_view.sql      |  18 ++++
 src/test/regress/sql/expressions.sql      |   2 +-
 src/tools/pgindent/typedefs.list          |   2 -
 25 files changed, 308 insertions(+), 389 deletions(-)

diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 241366fc8e..081419d065 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1520,6 +1520,21 @@
 { oid => '9977', descr => 'system user name',
   proname => 'system_user', provolatile => 's', prorettype => 'text',
   proargtypes => '', prosrc => 'system_user' },
+{ oid => '9978', descr => 'current date',
+  proname => 'current_date', provolatile => 's', prorettype => 'date',
+  proargtypes => '', prosrc => 'current_date' },
+{ oid => '9979', descr => 'current time',
+  proname => 'current_time', provolatile => 's', prorettype => 'timetz',
+  proargtypes => 'int4', prosrc => 'current_time', proisstrict => 'f' },
+{ oid => '9980', descr => 'current timestamp',
+  proname => 'current_timestamp', provolatile => 's', prorettype => 'timestamptz',
+  proargtypes => 'int4', prosrc => 'current_timestamp', proisstrict => 'f' },
+{ oid => '9981', descr => 'local time',
+  proname => 'localtime', provolatile => 's', prorettype => 'time',
+  proargtypes => 'int4', prosrc => 'sql_localtime', proisstrict => 'f' },
+{ oid => '9982', descr => 'local timestamp',
+  proname => 'localtimestamp', provolatile => 's', prorettype => 'timestamp',
+  proargtypes => 'int4', prosrc => 'sql_localtimestamp', proisstrict => 'f' },
 
 { oid => '744',
   proname => 'array_eq', prorettype => 'bool',
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index e14f15d435..0557302b92 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -170,7 +170,6 @@ typedef enum ExprEvalOp
 	EEOP_DISTINCT,
 	EEOP_NOT_DISTINCT,
 	EEOP_NULLIF,
-	EEOP_SQLVALUEFUNCTION,
 	EEOP_CURRENTOFEXPR,
 	EEOP_NEXTVALUEEXPR,
 	EEOP_ARRAYEXPR,
@@ -416,12 +415,6 @@ typedef struct ExprEvalStep
 			FunctionCallInfo fcinfo_data_in;
 		}			iocoerce;
 
-		/* for EEOP_SQLVALUEFUNCTION */
-		struct
-		{
-			SQLValueFunction *svf;
-		}			sqlvaluefunction;
-
 		/* for EEOP_NEXTVALUEEXPR */
 		struct
 		{
@@ -741,7 +734,6 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op,
 							  ExprContext *econtext);
 extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op,
 								ExprContext *econtext);
-extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalRowNull(ExprState *state, ExprEvalStep *op,
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index e818231e15..71293185fb 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1292,39 +1292,6 @@ typedef struct MinMaxExpr
 	int			location;		/* token location, or -1 if unknown */
 } MinMaxExpr;
 
-/*
- * SQLValueFunction - parameterless functions with special grammar productions
- *
- * The SQL standard categorizes some of these as <datetime value function>
- * and others as <general value specification>.  We call 'em SQLValueFunctions
- * for lack of a better term.  We store type and typmod of the result so that
- * some code doesn't need to know each function individually, and because
- * we would need to store typmod anyway for some of the datetime functions.
- * Note that currently, all variants return non-collating datatypes, so we do
- * not need a collation field; also, all these functions are stable.
- */
-typedef enum SQLValueFunctionOp
-{
-	SVFOP_CURRENT_DATE,
-	SVFOP_CURRENT_TIME,
-	SVFOP_CURRENT_TIME_N,
-	SVFOP_CURRENT_TIMESTAMP,
-	SVFOP_CURRENT_TIMESTAMP_N,
-	SVFOP_LOCALTIME,
-	SVFOP_LOCALTIME_N,
-	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N
-} SQLValueFunctionOp;
-
-typedef struct SQLValueFunction
-{
-	Expr		xpr;
-	SQLValueFunctionOp op;		/* which function this is */
-	Oid			type;			/* result type/typmod */
-	int32		typmod;
-	int			location;		/* token location, or -1 if unknown */
-} SQLValueFunction;
-
 /*
  * XmlExpr - various SQL/XML functions requiring special grammar productions
  *
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index 0bbe889128..fad4878722 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -96,7 +96,6 @@ TimeTzADTPGetDatum(const TimeTzADT *X)
 
 
 /* date.c */
-extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
@@ -104,9 +103,6 @@ extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
 extern void EncodeSpecialDate(DateADT dt, char *str);
-extern DateADT GetSQLCurrentDate(void);
-extern TimeTzADT *GetSQLCurrentTime(int32 typmod);
-extern TimeADT GetSQLLocalTime(int32 typmod);
 extern int	time2tm(TimeADT time, struct pg_tm *tm, fsec_t *fsec);
 extern int	timetz2tm(TimeTzADT *time, struct pg_tm *tm, fsec_t *fsec, int *tzp);
 extern int	tm2time(struct pg_tm *tm, fsec_t fsec, TimeADT *result);
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 76b7b4a3ca..7fd0b58825 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -93,11 +93,7 @@ extern PGDLLIMPORT TimestampTz PgReloadTime;
 
 /* Internal routines (not fmgr-callable) */
 
-extern int32 anytimestamp_typmod_check(bool istz, int32 typmod);
-
 extern TimestampTz GetCurrentTimestamp(void);
-extern TimestampTz GetSQLCurrentTimestamp(int32 typmod);
-extern Timestamp GetSQLLocalTimestamp(int32 typmod);
 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 								long *secs, int *microsecs);
 extern long TimestampDifferenceMilliseconds(TimestampTz start_time,
diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 30a048f6b0..4c3b4c3f8e 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -594,6 +594,32 @@ LANGUAGE internal
 STRICT IMMUTABLE PARALLEL SAFE
 AS 'unicode_is_normalized';
 
+-- Functions with SQL-mandated special syntax and some defaults.
+CREATE OR REPLACE FUNCTION
+  "current_time"(int4 DEFAULT NULL)
+RETURNS timetz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_time';
+CREATE OR REPLACE FUNCTION
+  "current_timestamp"(int4 DEFAULT NULL)
+RETURNS timestamptz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_timestamp';
+CREATE OR REPLACE FUNCTION
+  "localtime"(int4 DEFAULT NULL)
+RETURNS time
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtime';
+CREATE OR REPLACE FUNCTION
+  "localtimestamp"(int4 DEFAULT NULL)
+RETURNS timestamp
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtimestamp';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 25a94bbaaa..f9bfd79d48 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -2209,17 +2209,6 @@ ExecInitExprRec(Expr *node, ExprState *state,
 				break;
 			}
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				scratch.opcode = EEOP_SQLVALUEFUNCTION;
-				scratch.d.sqlvaluefunction.svf = svf;
-
-				ExprEvalPushStep(state, &scratch);
-				break;
-			}
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 6ebf5c287e..1dab2787b7 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -452,7 +452,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 		&&CASE_EEOP_DISTINCT,
 		&&CASE_EEOP_NOT_DISTINCT,
 		&&CASE_EEOP_NULLIF,
-		&&CASE_EEOP_SQLVALUEFUNCTION,
 		&&CASE_EEOP_CURRENTOFEXPR,
 		&&CASE_EEOP_NEXTVALUEEXPR,
 		&&CASE_EEOP_ARRAYEXPR,
@@ -1301,17 +1300,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 			EEO_NEXT();
 		}
 
-		EEO_CASE(EEOP_SQLVALUEFUNCTION)
-		{
-			/*
-			 * Doesn't seem worthwhile to have an inline implementation
-			 * efficiency-wise.
-			 */
-			ExecEvalSQLValueFunction(state, op);
-
-			EEO_NEXT();
-		}
-
 		EEO_CASE(EEOP_CURRENTOFEXPR)
 		{
 			/* error invocation uses space, and shouldn't ever occur */
@@ -2489,40 +2477,6 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 			 errmsg("no value found for parameter %d", paramId)));
 }
 
-/*
- * Evaluate a SQLValueFunction expression.
- */
-void
-ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
-{
-	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
-
-	*op->resnull = false;
-
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			*op->resvalue = DateADTGetDatum(GetSQLCurrentDate());
-			break;
-		case SVFOP_CURRENT_TIME:
-		case SVFOP_CURRENT_TIME_N:
-			*op->resvalue = TimeTzADTPGetDatum(GetSQLCurrentTime(svf->typmod));
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			*op->resvalue = TimestampTzGetDatum(GetSQLCurrentTimestamp(svf->typmod));
-			break;
-		case SVFOP_LOCALTIME:
-		case SVFOP_LOCALTIME_N:
-			*op->resvalue = TimeADTGetDatum(GetSQLLocalTime(svf->typmod));
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-		case SVFOP_LOCALTIMESTAMP_N:
-			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
-			break;
-	}
-}
-
 /*
  * Raise error if a CURRENT OF expression is evaluated.
  *
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index 95d0807bdd..f114337f8e 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -1549,12 +1549,6 @@ llvm_compile_expr(ExprState *state)
 					break;
 				}
 
-			case EEOP_SQLVALUEFUNCTION:
-				build_EvalXFunc(b, mod, "ExecEvalSQLValueFunction",
-								v_state, op);
-				LLVMBuildBr(b, opblocks[opno + 1]);
-				break;
-
 			case EEOP_CURRENTOFEXPR:
 				build_EvalXFunc(b, mod, "ExecEvalCurrentOfExpr",
 								v_state, op);
diff --git a/src/backend/jit/llvm/llvmjit_types.c b/src/backend/jit/llvm/llvmjit_types.c
index 90ac6b83b5..5b416c5642 100644
--- a/src/backend/jit/llvm/llvmjit_types.c
+++ b/src/backend/jit/llvm/llvmjit_types.c
@@ -126,7 +126,6 @@ void	   *referenced_functions[] =
 	ExecEvalRow,
 	ExecEvalRowNotNull,
 	ExecEvalRowNull,
-	ExecEvalSQLValueFunction,
 	ExecEvalScalarArrayOp,
 	ExecEvalHashedScalarArrayOp,
 	ExecEvalSubPlan,
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 2585a3175c..af8620ceb7 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -210,9 +210,6 @@ exprType(const Node *expr)
 		case T_MinMaxExpr:
 			type = ((const MinMaxExpr *) expr)->minmaxtype;
 			break;
-		case T_SQLValueFunction:
-			type = ((const SQLValueFunction *) expr)->type;
-			break;
 		case T_XmlExpr:
 			if (((const XmlExpr *) expr)->op == IS_DOCUMENT)
 				type = BOOLOID;
@@ -474,8 +471,6 @@ exprTypmod(const Node *expr)
 				return typmod;
 			}
 			break;
-		case T_SQLValueFunction:
-			return ((const SQLValueFunction *) expr)->typmod;
 		case T_CoerceToDomain:
 			return ((const CoerceToDomain *) expr)->resulttypmod;
 		case T_CoerceToDomainValue:
@@ -916,10 +911,6 @@ exprCollation(const Node *expr)
 		case T_MinMaxExpr:
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
-		case T_SQLValueFunction:
-			/* Returns a non-collatable type */
-			coll = InvalidOid;
-			break;
 		case T_XmlExpr:
 
 			/*
@@ -1140,9 +1131,6 @@ exprSetCollation(Node *expr, Oid collation)
 		case T_MinMaxExpr:
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
-		case T_SQLValueFunction:
-			Assert(collation == InvalidOid);
-			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
 				   (collation == DEFAULT_COLLATION_OID) :
@@ -1426,10 +1414,6 @@ exprLocation(const Node *expr)
 			/* GREATEST/LEAST keyword should always be the first thing */
 			loc = ((const MinMaxExpr *) expr)->location;
 			break;
-		case T_SQLValueFunction:
-			/* function keyword should always be the first thing */
-			loc = ((const SQLValueFunction *) expr)->location;
-			break;
 		case T_XmlExpr:
 			{
 				const XmlExpr *xexpr = (const XmlExpr *) expr;
@@ -1717,10 +1701,10 @@ set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
  * for themselves, in case additional checks should be made, or because they
  * have special rules about which parts of the tree need to be visited.
  *
- * Note: we ignore MinMaxExpr, SQLValueFunction, XmlExpr, CoerceToDomain,
- * and NextValueExpr nodes, because they do not contain SQL function OIDs.
- * However, they can invoke SQL-visible functions, so callers should take
- * thought about how to treat them.
+ * Note: we ignore MinMaxExpr, XmlExpr, CoerceToDomain, and NextValueExpr
+ * nodes, because they do not contain SQL function OIDs.  However, they can
+ * invoke SQL-visible functions, so callers should take thought about how
+ * to treat them.
  */
 bool
 check_functions_in_node(Node *node, check_function_callback checker,
@@ -1936,7 +1920,6 @@ expression_tree_walker_impl(Node *node,
 		case T_Const:
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -2673,7 +2656,6 @@ expression_tree_mutator_impl(Node *node,
 			break;
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -3587,7 +3569,6 @@ raw_expression_tree_walker_impl(Node *node,
 	{
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
-		case T_SQLValueFunction:
 		case T_Integer:
 		case T_Float:
 		case T_Boolean:
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 4c6b1d1f55..897309d7ec 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -4603,7 +4603,6 @@ cost_qual_eval_walker(Node *node, cost_qual_eval_context *context)
 		}
 	}
 	else if (IsA(node, MinMaxExpr) ||
-			 IsA(node, SQLValueFunction) ||
 			 IsA(node, XmlExpr) ||
 			 IsA(node, CoerceToDomain) ||
 			 IsA(node, NextValueExpr))
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 7fb32a0710..5db6574bfb 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -382,12 +382,6 @@ contain_mutable_functions_walker(Node *node, void *context)
 								context))
 		return true;
 
-	if (IsA(node, SQLValueFunction))
-	{
-		/* all variants of SQLValueFunction are stable */
-		return true;
-	}
-
 	if (IsA(node, NextValueExpr))
 	{
 		/* NextValueExpr is volatile */
@@ -536,8 +530,8 @@ contain_volatile_functions_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.
 	 */
 
 	/* Recurse to check arguments */
@@ -582,10 +576,9 @@ contain_volatile_functions_not_nextval_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
-	 * Also, since we're intentionally ignoring nextval(), presumably we
-	 * should ignore NextValueExpr.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.  Also, since we're intentionally
+	 * ignoring nextval(), presumably we should ignore NextValueExpr.
 	 */
 
 	/* Recurse to check arguments */
@@ -731,8 +724,8 @@ max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
 	 * (Note: in principle that's wrong because a domain constraint could
 	 * contain a parallel-unsafe function; but useful constraints probably
 	 * never would have such, and assuming they do would cripple use of
-	 * parallel query in the presence of domain types.)  SQLValueFunction
-	 * should be safe in all cases.  NextValueExpr is parallel-unsafe.
+	 * parallel query in the presence of domain types.)  NextValueExpr is
+	 * parallel-unsafe.
 	 */
 	if (IsA(node, CoerceToDomain))
 	{
@@ -1179,7 +1172,6 @@ contain_leaked_vars_walker(Node *node, void *context)
 		case T_CaseExpr:
 		case T_CaseTestExpr:
 		case T_RowExpr:
-		case T_SQLValueFunction:
 		case T_NullTest:
 		case T_BooleanTest:
 		case T_NextValueExpr:
@@ -3149,23 +3141,6 @@ eval_const_expressions_mutator(Node *node,
 				newcoalesce->location = coalesceexpr->location;
 				return (Node *) newcoalesce;
 			}
-		case T_SQLValueFunction:
-			{
-				/*
-				 * All variants of SQLValueFunction are stable, so if we are
-				 * estimating the expression's value, we should evaluate the
-				 * current function value.  Otherwise just copy.
-				 */
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				if (context->estimate)
-					return (Node *) evaluate_expr((Expr *) svf,
-												  svf->type,
-												  svf->typmod,
-												  InvalidOid);
-				else
-					return copyObject((Node *) svf);
-			}
 		case T_FieldSelect:
 			{
 				/*
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 605e9ec096..c8f6f942d1 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -198,8 +198,6 @@ static Node *makeAndExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeOrExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeNotExpr(Node *expr, int location);
 static Node *makeAArrayExpr(List *elements, int location);
-static Node *makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod,
-								  int location);
 static Node *makeXmlExpr(XmlExprOp op, char *name, List *named_args,
 						 List *args, int location);
 static List *mergeTableFuncParameters(List *func_args, List *columns);
@@ -15193,39 +15191,66 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_DATE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_DATE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_date"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_ROLE
 				{
@@ -18164,18 +18189,6 @@ makeAArrayExpr(List *elements, int location)
 	return (Node *) n;
 }
 
-static Node *
-makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod, int location)
-{
-	SQLValueFunction *svf = makeNode(SQLValueFunction);
-
-	svf->op = op;
-	/* svf->type will be filled during parse analysis */
-	svf->typmod = typmod;
-	svf->location = location;
-	return (Node *) svf;
-}
-
 static Node *
 makeXmlExpr(XmlExprOp op, char *name, List *named_args, List *args,
 			int location)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 9bde33b407..6b49d39c94 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -61,8 +61,6 @@ static Node *transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 static Node *transformRowExpr(ParseState *pstate, RowExpr *r, bool allowDefault);
 static Node *transformCoalesceExpr(ParseState *pstate, CoalesceExpr *c);
 static Node *transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m);
-static Node *transformSQLValueFunction(ParseState *pstate,
-									   SQLValueFunction *svf);
 static Node *transformXmlExpr(ParseState *pstate, XmlExpr *x);
 static Node *transformXmlSerialize(ParseState *pstate, XmlSerialize *xs);
 static Node *transformBooleanTest(ParseState *pstate, BooleanTest *b);
@@ -240,11 +238,6 @@ transformExprRecurse(ParseState *pstate, Node *expr)
 			result = transformMinMaxExpr(pstate, (MinMaxExpr *) expr);
 			break;
 
-		case T_SQLValueFunction:
-			result = transformSQLValueFunction(pstate,
-											   (SQLValueFunction *) expr);
-			break;
-
 		case T_XmlExpr:
 			result = transformXmlExpr(pstate, (XmlExpr *) expr);
 			break;
@@ -2191,51 +2184,6 @@ transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m)
 	return (Node *) newm;
 }
 
-static Node *
-transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
-{
-	/*
-	 * All we need to do is insert the correct result type and (where needed)
-	 * validate the typmod, so we just modify the node in-place.
-	 */
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			svf->type = DATEOID;
-			break;
-		case SVFOP_CURRENT_TIME:
-			svf->type = TIMETZOID;
-			break;
-		case SVFOP_CURRENT_TIME_N:
-			svf->type = TIMETZOID;
-			svf->typmod = anytime_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-			svf->type = TIMESTAMPTZOID;
-			break;
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			svf->type = TIMESTAMPTZOID;
-			svf->typmod = anytimestamp_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_LOCALTIME:
-			svf->type = TIMEOID;
-			break;
-		case SVFOP_LOCALTIME_N:
-			svf->type = TIMEOID;
-			svf->typmod = anytime_typmod_check(false, svf->typmod);
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-			svf->type = TIMESTAMPOID;
-			break;
-		case SVFOP_LOCALTIMESTAMP_N:
-			svf->type = TIMESTAMPOID;
-			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
-			break;
-	}
-
-	return (Node *) svf;
-}
-
 static Node *
 transformXmlExpr(ParseState *pstate, XmlExpr *x)
 {
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index f54591a987..8e0d6fd01f 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1872,31 +1872,6 @@ FigureColnameInternal(Node *node, char **name)
 					return 2;
 			}
 			break;
-		case T_SQLValueFunction:
-			/* make these act like a function or variable */
-			switch (((SQLValueFunction *) node)->op)
-			{
-				case SVFOP_CURRENT_DATE:
-					*name = "current_date";
-					return 2;
-				case SVFOP_CURRENT_TIME:
-				case SVFOP_CURRENT_TIME_N:
-					*name = "current_time";
-					return 2;
-				case SVFOP_CURRENT_TIMESTAMP:
-				case SVFOP_CURRENT_TIMESTAMP_N:
-					*name = "current_timestamp";
-					return 2;
-				case SVFOP_LOCALTIME:
-				case SVFOP_LOCALTIME_N:
-					*name = "localtime";
-					return 2;
-				case SVFOP_LOCALTIMESTAMP:
-				case SVFOP_LOCALTIMESTAMP_N:
-					*name = "localtimestamp";
-					return 2;
-			}
-			break;
 		case T_XmlExpr:
 			/* make SQL/XML functions act like a regular function */
 			switch (((XmlExpr *) node)->op)
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index a2bdde0459..10c11e00db 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -46,27 +46,6 @@
 
 /* common code for timetypmodin and timetztypmodin */
 static int32
-anytime_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIME
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytime_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytime_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -87,6 +66,26 @@ anytime_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytime_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIME
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytime_typmod_check(istz, tl[0]);
+}
+
 /* common code for timetypmodout and timetztypmodout */
 static char *
 anytime_typmodout(bool istz, int32 typmod)
@@ -296,10 +295,10 @@ EncodeSpecialDate(DateADT dt, char *str)
 
 
 /*
- * GetSQLCurrentDate -- implements CURRENT_DATE
+ * current_date -- implements CURRENT_DATE
  */
-DateADT
-GetSQLCurrentDate(void)
+Datum
+current_date(PG_FUNCTION_ARGS)
 {
 	struct pg_tm tm;
 
@@ -325,46 +324,62 @@ GetSQLCurrentDate(void)
 		cache_mday = tm.tm_mday;
 	}
 
-	return cache_date;
+	return DateADTGetDatum(cache_date);
 }
 
 /*
- * GetSQLCurrentTime -- implements CURRENT_TIME, CURRENT_TIME(n)
+ * current_time -- implements CURRENT_TIME, CURRENT_TIME(n)
  */
-TimeTzADT *
-GetSQLCurrentTime(int32 typmod)
+Datum
+current_time(PG_FUNCTION_ARGS)
 {
 	TimeTzADT  *result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(true, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	result = (TimeTzADT *) palloc(sizeof(TimeTzADT));
 	tm2timetz(tm, fsec, tz, result);
 	AdjustTimeForTypmod(&(result->time), typmod);
-	return result;
+
+	return TimeTzADTPGetDatum(result);
 }
 
 /*
- * GetSQLLocalTime -- implements LOCALTIME, LOCALTIME(n)
+ * sql_localtime -- implements LOCALTIME, LOCALTIME(n)
  */
-TimeADT
-GetSQLLocalTime(int32 typmod)
+Datum
+sql_localtime(PG_FUNCTION_ARGS)
 {
 	TimeADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(false, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	tm2time(tm, fsec, &result);
 	AdjustTimeForTypmod(&result, typmod);
-	return result;
+
+	return TimeADTGetDatum(result);
 }
 
 
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index f95289f11c..48ad54ecf1 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8180,7 +8180,6 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
 		case T_RowExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 		case T_NextValueExpr:
 		case T_NullIfExpr:
@@ -9160,49 +9159,6 @@ get_rule_expr(Node *node, deparse_context *context,
 			}
 			break;
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				/*
-				 * Note: this code knows that typmod for time, timestamp, and
-				 * timestamptz just prints as integer.
-				 */
-				switch (svf->op)
-				{
-					case SVFOP_CURRENT_DATE:
-						appendStringInfoString(buf, "CURRENT_DATE");
-						break;
-					case SVFOP_CURRENT_TIME:
-						appendStringInfoString(buf, "CURRENT_TIME");
-						break;
-					case SVFOP_CURRENT_TIME_N:
-						appendStringInfo(buf, "CURRENT_TIME(%d)", svf->typmod);
-						break;
-					case SVFOP_CURRENT_TIMESTAMP:
-						appendStringInfoString(buf, "CURRENT_TIMESTAMP");
-						break;
-					case SVFOP_CURRENT_TIMESTAMP_N:
-						appendStringInfo(buf, "CURRENT_TIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-					case SVFOP_LOCALTIME:
-						appendStringInfoString(buf, "LOCALTIME");
-						break;
-					case SVFOP_LOCALTIME_N:
-						appendStringInfo(buf, "LOCALTIME(%d)", svf->typmod);
-						break;
-					case SVFOP_LOCALTIMESTAMP:
-						appendStringInfoString(buf, "LOCALTIMESTAMP");
-						break;
-					case SVFOP_LOCALTIMESTAMP_N:
-						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-				}
-			}
-			break;
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
@@ -9728,7 +9684,6 @@ looks_like_function(Node *node)
 		case T_NullIfExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 			/* these are all accepted by func_expr_common_subexpr */
 			return true;
@@ -10322,6 +10277,70 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
 
+		case F_CURRENT_DATE:
+			appendStringInfoString(buf, "CURRENT_DATE");
+			return true;
+		case F_CURRENT_TIME:
+			appendStringInfoString(buf, "CURRENT_TIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_CURRENT_TIMESTAMP:
+			appendStringInfoString(buf, "CURRENT_TIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIME:
+			appendStringInfoString(buf, "LOCALTIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIMESTAMP:
+			appendStringInfoString(buf, "LOCALTIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+
 		case F_XMLEXISTS:
 			/* XMLEXISTS ... extra parens because args are c_expr */
 			appendStringInfoString(buf, "XMLEXISTS((");
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index d8552a1f18..ef92323fd0 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -81,27 +81,6 @@ static Timestamp timestamptz2timestamp(TimestampTz timestamp);
 
 /* common code for timestamptypmodin and timestamptztypmodin */
 static int32
-anytimestamp_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIMESTAMP
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytimestamp_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytimestamp_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -122,6 +101,26 @@ anytimestamp_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytimestamp_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIMESTAMP
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytimestamp_typmod_check(istz, tl[0]);
+}
+
 /* common code for timestamptypmodout and timestamptztypmodout */
 static char *
 anytimestamp_typmodout(bool istz, int32 typmod)
@@ -1586,33 +1585,48 @@ GetCurrentTimestamp(void)
 }
 
 /*
- * GetSQLCurrentTimestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
+ * current_timestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
  */
-TimestampTz
-GetSQLCurrentTimestamp(int32 typmod)
+Datum
+current_timestamp(PG_FUNCTION_ARGS)
 {
 	TimestampTz ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(true, typmod);
+	}
 
 	ts = GetCurrentTransactionStartTimestamp();
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampTzGetDatum(ts);
 }
 
 /*
- * GetSQLLocalTimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
+ * sql_localtimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
  */
-Timestamp
-GetSQLLocalTimestamp(int32 typmod)
+Datum
+sql_localtimestamp(PG_FUNCTION_ARGS)
 {
 	Timestamp	ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(false, typmod);
+	}
 
 	ts = timestamptz2timestamp(GetCurrentTransactionStartTimestamp());
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampGetDatum(ts);
 }
 
+
 /*
  * timeofday(*) -- returns the current time as a text.
  */
diff --git a/src/backend/utils/misc/queryjumble.c b/src/backend/utils/misc/queryjumble.c
index a8508463e7..0ace74de78 100644
--- a/src/backend/utils/misc/queryjumble.c
+++ b/src/backend/utils/misc/queryjumble.c
@@ -606,15 +606,6 @@ JumbleExpr(JumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) mmexpr->args);
 			}
 			break;
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				APP_JUMB(svf->op);
-				/* type is fully determined by op */
-				APP_JUMB(svf->typmod);
-			}
-			break;
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/test/regress/expected/create_view.out b/src/test/regress/expected/create_view.out
index e7f7323113..f9bbad00df 100644
--- a/src/test/regress/expected/create_view.out
+++ b/src/test/regress/expected/create_view.out
@@ -1941,6 +1941,24 @@ select
   trim(E'\\000'::bytea from E'\\000Tom\\000'::bytea) as btb,
   trim(leading E'\\000'::bytea from E'\\000Tom\\000'::bytea) as ltb,
   trim(trailing E'\\000'::bytea from E'\\000Tom\\000'::bytea) as rtb,
+  CURRENT_DATE as cd,
+  (select * from CURRENT_DATE) as cd2,
+  CURRENT_TIME as ct,
+  (select * from CURRENT_TIME) as ct2,
+  CURRENT_TIME (1) as ct3,
+  (select * from CURRENT_TIME (1)) as ct4,
+  CURRENT_TIMESTAMP as ct5,
+  (select * from CURRENT_TIMESTAMP) as ct6,
+  CURRENT_TIMESTAMP (1) as ct7,
+  (select * from CURRENT_TIMESTAMP (1)) as ct8,
+  LOCALTIME as lt1,
+  (select * from LOCALTIME) as lt2,
+  LOCALTIME (1) as lt3,
+  (select * from LOCALTIME (1)) as lt4,
+  LOCALTIMESTAMP as lt5,
+  (select * from LOCALTIMESTAMP) as lt6,
+  LOCALTIMESTAMP (1) as lt7,
+  (select * from LOCALTIMESTAMP (1)) as lt8,
   CURRENT_CATALOG as ca,
   (select * from CURRENT_CATALOG) as ca2,
   CURRENT_ROLE as cr,
@@ -1976,6 +1994,33 @@ select pg_get_viewdef('tt201v', true);
      TRIM(BOTH '\x00'::bytea FROM '\x00546f6d00'::bytea) AS btb,                              +
      TRIM(LEADING '\x00'::bytea FROM '\x00546f6d00'::bytea) AS ltb,                           +
      TRIM(TRAILING '\x00'::bytea FROM '\x00546f6d00'::bytea) AS rtb,                          +
+     CURRENT_DATE AS cd,                                                                      +
+     ( SELECT "current_date"."current_date"                                                   +
+            FROM CURRENT_DATE "current_date"("current_date")) AS cd2,                         +
+     CURRENT_TIME AS ct,                                                                      +
+     ( SELECT "current_time"."current_time"                                                   +
+            FROM CURRENT_TIME "current_time"("current_time")) AS ct2,                         +
+     CURRENT_TIME(1) AS ct3,                                                                  +
+     ( SELECT "current_time"."current_time"                                                   +
+            FROM CURRENT_TIME(1) "current_time"("current_time")) AS ct4,                      +
+     CURRENT_TIMESTAMP AS ct5,                                                                +
+     ( SELECT "current_timestamp"."current_timestamp"                                         +
+            FROM CURRENT_TIMESTAMP "current_timestamp"("current_timestamp")) AS ct6,          +
+     CURRENT_TIMESTAMP(1) AS ct7,                                                             +
+     ( SELECT "current_timestamp"."current_timestamp"                                         +
+            FROM CURRENT_TIMESTAMP(1) "current_timestamp"("current_timestamp")) AS ct8,       +
+     LOCALTIME AS lt1,                                                                        +
+     ( SELECT "localtime"."localtime"                                                         +
+            FROM LOCALTIME "localtime"("localtime")) AS lt2,                                  +
+     LOCALTIME(1) AS lt3,                                                                     +
+     ( SELECT "localtime"."localtime"                                                         +
+            FROM LOCALTIME(1) "localtime"("localtime")) AS lt4,                               +
+     LOCALTIMESTAMP AS lt5,                                                                   +
+     ( SELECT "localtimestamp"."localtimestamp"                                               +
+            FROM LOCALTIMESTAMP "localtimestamp"("localtimestamp")) AS lt6,                   +
+     LOCALTIMESTAMP(1) AS lt7,                                                                +
+     ( SELECT "localtimestamp"."localtimestamp"                                               +
+            FROM LOCALTIMESTAMP(1) "localtimestamp"("localtimestamp")) AS lt8,                +
      CURRENT_CATALOG AS ca,                                                                   +
      ( SELECT "current_catalog"."current_catalog"                                             +
             FROM CURRENT_CATALOG "current_catalog"("current_catalog")) AS ca2,                +
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 5bf39fd9aa..28a20900f1 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -2,7 +2,7 @@
 -- expression evaluation tests that don't fit into a more specific file
 --
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 -- current_date  (always matches because of transactional behaviour)
 SELECT date(now())::text = current_date::text;
diff --git a/src/test/regress/sql/create_view.sql b/src/test/regress/sql/create_view.sql
index 04fc0ba35e..bd189b2209 100644
--- a/src/test/regress/sql/create_view.sql
+++ b/src/test/regress/sql/create_view.sql
@@ -722,6 +722,24 @@ select
   trim(E'\\000'::bytea from E'\\000Tom\\000'::bytea) as btb,
   trim(leading E'\\000'::bytea from E'\\000Tom\\000'::bytea) as ltb,
   trim(trailing E'\\000'::bytea from E'\\000Tom\\000'::bytea) as rtb,
+  CURRENT_DATE as cd,
+  (select * from CURRENT_DATE) as cd2,
+  CURRENT_TIME as ct,
+  (select * from CURRENT_TIME) as ct2,
+  CURRENT_TIME (1) as ct3,
+  (select * from CURRENT_TIME (1)) as ct4,
+  CURRENT_TIMESTAMP as ct5,
+  (select * from CURRENT_TIMESTAMP) as ct6,
+  CURRENT_TIMESTAMP (1) as ct7,
+  (select * from CURRENT_TIMESTAMP (1)) as ct8,
+  LOCALTIME as lt1,
+  (select * from LOCALTIME) as lt2,
+  LOCALTIME (1) as lt3,
+  (select * from LOCALTIME (1)) as lt4,
+  LOCALTIMESTAMP as lt5,
+  (select * from LOCALTIMESTAMP) as lt6,
+  LOCALTIMESTAMP (1) as lt7,
+  (select * from LOCALTIMESTAMP (1)) as lt8,
   CURRENT_CATALOG as ca,
   (select * from CURRENT_CATALOG) as ca2,
   CURRENT_ROLE as cr,
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index 0e163cc0d7..f9a0299d17 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -3,7 +3,7 @@
 --
 
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 
 
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index d9b839c979..5ec61b26b4 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2397,8 +2397,6 @@ SQLFunctionCache
 SQLFunctionCachePtr
 SQLFunctionParseInfo
 SQLFunctionParseInfoPtr
-SQLValueFunction
-SQLValueFunctionOp
 SSL
 SSLExtensionInfoContext
 SSL_CTX
-- 
2.37.2

From 1d2d6e4803f3ab3e9d2c29efcc8dee0f8a53d699 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Tue, 25 Oct 2022 14:15:14 +0900
Subject: [PATCH v3 1/2] Remove from SQLValueFunction all the entries using
 "name" as return type

This commit changes six SQL keywords to use COERCE_SQL_SYNTAX rather
than SQLValueFunction:
- CURRENT_ROLE
- CURRENT_USER
- USER
- SESSION_USER
- CURRENT_CATALOG
- CURRENT_SCHEMA
Among the six, "user", "current_role" and "current_catalog" require
specific SQL functions to allow ruleutils.c to map them to the SQL
keywords these require when using COERCE_SQL_SYNTAX.  Having
pg_proc.proname match with the keyword ensures that the compatibility
remains the same when projecting any of these keywords in a FROM clause
to an attribute name when an alias is not specified.  Tests are added to
make sure that the mapping happens from the SQL keyword is correct,
using a view defition that feeds on these keywords in one of the tests
introduced by 40c24bf (both in a SELECT clause and when using each
keyword in a FROM clause).

SQLValueFunction is reduced to half its contents after this change,
simplifying its logic a bit as there is no need to enforce a C collation
anymore.  I have made a few performance tests, with a million-ish calls
to these keywords without seeing a difference in run-time or in perf
profiles.  The remaining SQLValueFunctions relate to timestamps.

Bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/pg_proc.dat       |  9 +++++++
 src/include/nodes/primnodes.h         |  8 +-----
 src/backend/executor/execExprInterp.c | 27 --------------------
 src/backend/nodes/nodeFuncs.c         | 11 +++-----
 src/backend/parser/gram.y             | 30 +++++++++++++++++-----
 src/backend/parser/parse_expr.c       |  8 ------
 src/backend/parser/parse_target.c     | 18 --------------
 src/backend/utils/adt/ruleutils.c     | 36 +++++++++++++--------------
 8 files changed, 55 insertions(+), 92 deletions(-)

diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 62a5b8e655..241366fc8e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1505,6 +1505,15 @@
 { oid => '745', descr => 'current user name',
   proname => 'current_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'current_user' },
+{ oid => '9695', descr => 'current role name',
+  proname => 'current_role', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_user' },
+{ oid => '9696', descr => 'user name',
+  proname => 'user', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_user' },
+{ oid => '9697', descr => 'name of the current database',
+  proname => 'current_catalog', provolatile => 's', prorettype => 'name',
+  proargtypes => '', prosrc => 'current_database' },
 { oid => '746', descr => 'session user name',
   proname => 'session_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'session_user' },
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index f71f551782..f6dd27edcc 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1313,13 +1313,7 @@ typedef enum SQLValueFunctionOp
 	SVFOP_LOCALTIME,
 	SVFOP_LOCALTIME_N,
 	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N,
-	SVFOP_CURRENT_ROLE,
-	SVFOP_CURRENT_USER,
-	SVFOP_USER,
-	SVFOP_SESSION_USER,
-	SVFOP_CURRENT_CATALOG,
-	SVFOP_CURRENT_SCHEMA
+	SVFOP_LOCALTIMESTAMP_N
 } SQLValueFunctionOp;
 
 typedef struct SQLValueFunction
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 9b9bbf00a9..6ebf5c287e 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -2495,15 +2495,10 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 void
 ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
 {
-	LOCAL_FCINFO(fcinfo, 0);
 	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
 
 	*op->resnull = false;
 
-	/*
-	 * Note: current_schema() can return NULL.  current_user() etc currently
-	 * cannot, but might as well code those cases the same way for safety.
-	 */
 	switch (svf->op)
 	{
 		case SVFOP_CURRENT_DATE:
@@ -2525,28 +2520,6 @@ ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
 		case SVFOP_LOCALTIMESTAMP_N:
 			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
 			break;
-		case SVFOP_CURRENT_ROLE:
-		case SVFOP_CURRENT_USER:
-		case SVFOP_USER:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_user(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_SESSION_USER:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = session_user(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_CURRENT_CATALOG:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_database(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
-		case SVFOP_CURRENT_SCHEMA:
-			InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
-			*op->resvalue = current_schema(fcinfo);
-			*op->resnull = fcinfo->isnull;
-			break;
 	}
 }
 
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 0a7b22f97e..2585a3175c 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -917,11 +917,8 @@ exprCollation(const Node *expr)
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
 		case T_SQLValueFunction:
-			/* Returns either NAME or a non-collatable type */
-			if (((const SQLValueFunction *) expr)->type == NAMEOID)
-				coll = C_COLLATION_OID;
-			else
-				coll = InvalidOid;
+			/* Returns a non-collatable type */
+			coll = InvalidOid;
 			break;
 		case T_XmlExpr:
 
@@ -1144,9 +1141,7 @@ exprSetCollation(Node *expr, Oid collation)
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
 		case T_SQLValueFunction:
-			Assert((((SQLValueFunction *) expr)->type == NAMEOID) ?
-				   (collation == C_COLLATION_OID) :
-				   (collation == InvalidOid));
+			Assert(collation == InvalidOid);
 			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 737bd2d06d..605e9ec096 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -15229,15 +15229,24 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_ROLE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_ROLE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_role"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| SESSION_USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_SESSION_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("session_user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| SYSTEM_USER
 				{
@@ -15248,15 +15257,24 @@ func_expr_common_subexpr:
 				}
 			| USER
 				{
-					$$ = makeSQLValueFunction(SVFOP_USER, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("user"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_CATALOG
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_CATALOG, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_catalog"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_SCHEMA
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_SCHEMA, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_schema"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CAST '(' a_expr AS Typename ')'
 				{ $$ = makeTypeCast($3, $5, @1); }
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index e5fc708c8a..0fdbf82f3a 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -2231,14 +2231,6 @@ transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
 			svf->type = TIMESTAMPOID;
 			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
 			break;
-		case SVFOP_CURRENT_ROLE:
-		case SVFOP_CURRENT_USER:
-		case SVFOP_USER:
-		case SVFOP_SESSION_USER:
-		case SVFOP_CURRENT_CATALOG:
-		case SVFOP_CURRENT_SCHEMA:
-			svf->type = NAMEOID;
-			break;
 	}
 
 	return (Node *) svf;
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index bd8057bc3e..f54591a987 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1895,24 +1895,6 @@ FigureColnameInternal(Node *node, char **name)
 				case SVFOP_LOCALTIMESTAMP_N:
 					*name = "localtimestamp";
 					return 2;
-				case SVFOP_CURRENT_ROLE:
-					*name = "current_role";
-					return 2;
-				case SVFOP_CURRENT_USER:
-					*name = "current_user";
-					return 2;
-				case SVFOP_USER:
-					*name = "user";
-					return 2;
-				case SVFOP_SESSION_USER:
-					*name = "session_user";
-					return 2;
-				case SVFOP_CURRENT_CATALOG:
-					*name = "current_catalog";
-					return 2;
-				case SVFOP_CURRENT_SCHEMA:
-					*name = "current_schema";
-					return 2;
 			}
 			break;
 		case T_XmlExpr:
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 70d723e80c..f95289f11c 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -9199,24 +9199,6 @@ get_rule_expr(Node *node, deparse_context *context,
 						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
 										 svf->typmod);
 						break;
-					case SVFOP_CURRENT_ROLE:
-						appendStringInfoString(buf, "CURRENT_ROLE");
-						break;
-					case SVFOP_CURRENT_USER:
-						appendStringInfoString(buf, "CURRENT_USER");
-						break;
-					case SVFOP_USER:
-						appendStringInfoString(buf, "USER");
-						break;
-					case SVFOP_SESSION_USER:
-						appendStringInfoString(buf, "SESSION_USER");
-						break;
-					case SVFOP_CURRENT_CATALOG:
-						appendStringInfoString(buf, "CURRENT_CATALOG");
-						break;
-					case SVFOP_CURRENT_SCHEMA:
-						appendStringInfoString(buf, "CURRENT_SCHEMA");
-						break;
 				}
 			}
 			break;
@@ -10318,6 +10300,24 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoChar(buf, ')');
 			return true;
 
+		case F_CURRENT_CATALOG:
+			appendStringInfoString(buf, "CURRENT_CATALOG");
+			return true;
+		case F_CURRENT_ROLE:
+			appendStringInfoString(buf, "CURRENT_ROLE");
+			return true;
+		case F_CURRENT_SCHEMA:
+			appendStringInfoString(buf, "CURRENT_SCHEMA");
+			return true;
+		case F_CURRENT_USER:
+			appendStringInfoString(buf, "CURRENT_USER");
+			return true;
+		case F_USER:
+			appendStringInfoString(buf, "USER");
+			return true;
+		case F_SESSION_USER:
+			appendStringInfoString(buf, "SESSION_USER");
+			return true;
 		case F_SYSTEM_USER:
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
-- 
2.37.2

From 208c5e9c3021bbb6b9ab929a66adb404fd0088c6 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Fri, 21 Oct 2022 14:19:41 +0900
Subject: [PATCH v3 2/2] Replace SQLValueFunction by direct function calls

This impacts 9 patterns where the SQL grammar takes priority:
- localtime, that can take a typmod.
- localtimestamp, that can take a typmod.
- current_time, that can take a typmod.
- current_timestamp, that can take a typmod.
- current_date.

Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to keep compatibility (when a keyword is specified in a
SELECT or in a FROM clause without an alias), with tests to cover all
that.

XXX: bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/pg_proc.dat           |  15 +++
 src/include/executor/execExpr.h           |   8 --
 src/include/nodes/primnodes.h             |  33 -------
 src/include/utils/date.h                  |   4 -
 src/include/utils/timestamp.h             |   4 -
 src/backend/catalog/system_functions.sql  |  26 ++++++
 src/backend/executor/execExpr.c           |  11 ---
 src/backend/executor/execExprInterp.c     |  46 ---------
 src/backend/jit/llvm/llvmjit_expr.c       |   6 --
 src/backend/jit/llvm/llvmjit_types.c      |   1 -
 src/backend/nodes/nodeFuncs.c             |  27 +-----
 src/backend/optimizer/path/costsize.c     |   1 -
 src/backend/optimizer/util/clauses.c      |  39 ++------
 src/backend/parser/gram.y                 |  59 +++++++-----
 src/backend/parser/parse_expr.c           |  52 -----------
 src/backend/parser/parse_target.c         |  25 -----
 src/backend/utils/adt/date.c              |  81 +++++++++-------
 src/backend/utils/adt/ruleutils.c         | 109 +++++++++++++---------
 src/backend/utils/adt/timestamp.c         |  72 ++++++++------
 src/backend/utils/misc/queryjumble.c      |   9 --
 src/test/regress/expected/expressions.out |   2 +-
 src/test/regress/sql/expressions.sql      |   2 +-
 src/tools/pgindent/typedefs.list          |   2 -
 23 files changed, 245 insertions(+), 389 deletions(-)

diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 241366fc8e..081419d065 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1520,6 +1520,21 @@
 { oid => '9977', descr => 'system user name',
   proname => 'system_user', provolatile => 's', prorettype => 'text',
   proargtypes => '', prosrc => 'system_user' },
+{ oid => '9978', descr => 'current date',
+  proname => 'current_date', provolatile => 's', prorettype => 'date',
+  proargtypes => '', prosrc => 'current_date' },
+{ oid => '9979', descr => 'current time',
+  proname => 'current_time', provolatile => 's', prorettype => 'timetz',
+  proargtypes => 'int4', prosrc => 'current_time', proisstrict => 'f' },
+{ oid => '9980', descr => 'current timestamp',
+  proname => 'current_timestamp', provolatile => 's', prorettype => 'timestamptz',
+  proargtypes => 'int4', prosrc => 'current_timestamp', proisstrict => 'f' },
+{ oid => '9981', descr => 'local time',
+  proname => 'localtime', provolatile => 's', prorettype => 'time',
+  proargtypes => 'int4', prosrc => 'sql_localtime', proisstrict => 'f' },
+{ oid => '9982', descr => 'local timestamp',
+  proname => 'localtimestamp', provolatile => 's', prorettype => 'timestamp',
+  proargtypes => 'int4', prosrc => 'sql_localtimestamp', proisstrict => 'f' },
 
 { oid => '744',
   proname => 'array_eq', prorettype => 'bool',
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index e14f15d435..0557302b92 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -170,7 +170,6 @@ typedef enum ExprEvalOp
 	EEOP_DISTINCT,
 	EEOP_NOT_DISTINCT,
 	EEOP_NULLIF,
-	EEOP_SQLVALUEFUNCTION,
 	EEOP_CURRENTOFEXPR,
 	EEOP_NEXTVALUEEXPR,
 	EEOP_ARRAYEXPR,
@@ -416,12 +415,6 @@ typedef struct ExprEvalStep
 			FunctionCallInfo fcinfo_data_in;
 		}			iocoerce;
 
-		/* for EEOP_SQLVALUEFUNCTION */
-		struct
-		{
-			SQLValueFunction *svf;
-		}			sqlvaluefunction;
-
 		/* for EEOP_NEXTVALUEEXPR */
 		struct
 		{
@@ -741,7 +734,6 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op,
 							  ExprContext *econtext);
 extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op,
 								ExprContext *econtext);
-extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalRowNull(ExprState *state, ExprEvalStep *op,
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index f6dd27edcc..74f228d959 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1292,39 +1292,6 @@ typedef struct MinMaxExpr
 	int			location;		/* token location, or -1 if unknown */
 } MinMaxExpr;
 
-/*
- * SQLValueFunction - parameterless functions with special grammar productions
- *
- * The SQL standard categorizes some of these as <datetime value function>
- * and others as <general value specification>.  We call 'em SQLValueFunctions
- * for lack of a better term.  We store type and typmod of the result so that
- * some code doesn't need to know each function individually, and because
- * we would need to store typmod anyway for some of the datetime functions.
- * Note that currently, all variants return non-collating datatypes, so we do
- * not need a collation field; also, all these functions are stable.
- */
-typedef enum SQLValueFunctionOp
-{
-	SVFOP_CURRENT_DATE,
-	SVFOP_CURRENT_TIME,
-	SVFOP_CURRENT_TIME_N,
-	SVFOP_CURRENT_TIMESTAMP,
-	SVFOP_CURRENT_TIMESTAMP_N,
-	SVFOP_LOCALTIME,
-	SVFOP_LOCALTIME_N,
-	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N
-} SQLValueFunctionOp;
-
-typedef struct SQLValueFunction
-{
-	Expr		xpr;
-	SQLValueFunctionOp op;		/* which function this is */
-	Oid			type;			/* result type/typmod */
-	int32		typmod;
-	int			location;		/* token location, or -1 if unknown */
-} SQLValueFunction;
-
 /*
  * XmlExpr - various SQL/XML functions requiring special grammar productions
  *
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index 0bbe889128..fad4878722 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -96,7 +96,6 @@ TimeTzADTPGetDatum(const TimeTzADT *X)
 
 
 /* date.c */
-extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
@@ -104,9 +103,6 @@ extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
 extern void EncodeSpecialDate(DateADT dt, char *str);
-extern DateADT GetSQLCurrentDate(void);
-extern TimeTzADT *GetSQLCurrentTime(int32 typmod);
-extern TimeADT GetSQLLocalTime(int32 typmod);
 extern int	time2tm(TimeADT time, struct pg_tm *tm, fsec_t *fsec);
 extern int	timetz2tm(TimeTzADT *time, struct pg_tm *tm, fsec_t *fsec, int *tzp);
 extern int	tm2time(struct pg_tm *tm, fsec_t fsec, TimeADT *result);
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 76b7b4a3ca..7fd0b58825 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -93,11 +93,7 @@ extern PGDLLIMPORT TimestampTz PgReloadTime;
 
 /* Internal routines (not fmgr-callable) */
 
-extern int32 anytimestamp_typmod_check(bool istz, int32 typmod);
-
 extern TimestampTz GetCurrentTimestamp(void);
-extern TimestampTz GetSQLCurrentTimestamp(int32 typmod);
-extern Timestamp GetSQLLocalTimestamp(int32 typmod);
 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 								long *secs, int *microsecs);
 extern long TimestampDifferenceMilliseconds(TimestampTz start_time,
diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 30a048f6b0..4c3b4c3f8e 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -594,6 +594,32 @@ LANGUAGE internal
 STRICT IMMUTABLE PARALLEL SAFE
 AS 'unicode_is_normalized';
 
+-- Functions with SQL-mandated special syntax and some defaults.
+CREATE OR REPLACE FUNCTION
+  "current_time"(int4 DEFAULT NULL)
+RETURNS timetz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_time';
+CREATE OR REPLACE FUNCTION
+  "current_timestamp"(int4 DEFAULT NULL)
+RETURNS timestamptz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_timestamp';
+CREATE OR REPLACE FUNCTION
+  "localtime"(int4 DEFAULT NULL)
+RETURNS time
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtime';
+CREATE OR REPLACE FUNCTION
+  "localtimestamp"(int4 DEFAULT NULL)
+RETURNS timestamp
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtimestamp';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 25a94bbaaa..f9bfd79d48 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -2209,17 +2209,6 @@ ExecInitExprRec(Expr *node, ExprState *state,
 				break;
 			}
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				scratch.opcode = EEOP_SQLVALUEFUNCTION;
-				scratch.d.sqlvaluefunction.svf = svf;
-
-				ExprEvalPushStep(state, &scratch);
-				break;
-			}
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 6ebf5c287e..1dab2787b7 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -452,7 +452,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 		&&CASE_EEOP_DISTINCT,
 		&&CASE_EEOP_NOT_DISTINCT,
 		&&CASE_EEOP_NULLIF,
-		&&CASE_EEOP_SQLVALUEFUNCTION,
 		&&CASE_EEOP_CURRENTOFEXPR,
 		&&CASE_EEOP_NEXTVALUEEXPR,
 		&&CASE_EEOP_ARRAYEXPR,
@@ -1301,17 +1300,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 			EEO_NEXT();
 		}
 
-		EEO_CASE(EEOP_SQLVALUEFUNCTION)
-		{
-			/*
-			 * Doesn't seem worthwhile to have an inline implementation
-			 * efficiency-wise.
-			 */
-			ExecEvalSQLValueFunction(state, op);
-
-			EEO_NEXT();
-		}
-
 		EEO_CASE(EEOP_CURRENTOFEXPR)
 		{
 			/* error invocation uses space, and shouldn't ever occur */
@@ -2489,40 +2477,6 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 			 errmsg("no value found for parameter %d", paramId)));
 }
 
-/*
- * Evaluate a SQLValueFunction expression.
- */
-void
-ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
-{
-	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
-
-	*op->resnull = false;
-
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			*op->resvalue = DateADTGetDatum(GetSQLCurrentDate());
-			break;
-		case SVFOP_CURRENT_TIME:
-		case SVFOP_CURRENT_TIME_N:
-			*op->resvalue = TimeTzADTPGetDatum(GetSQLCurrentTime(svf->typmod));
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			*op->resvalue = TimestampTzGetDatum(GetSQLCurrentTimestamp(svf->typmod));
-			break;
-		case SVFOP_LOCALTIME:
-		case SVFOP_LOCALTIME_N:
-			*op->resvalue = TimeADTGetDatum(GetSQLLocalTime(svf->typmod));
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-		case SVFOP_LOCALTIMESTAMP_N:
-			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
-			break;
-	}
-}
-
 /*
  * Raise error if a CURRENT OF expression is evaluated.
  *
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index 95d0807bdd..f114337f8e 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -1549,12 +1549,6 @@ llvm_compile_expr(ExprState *state)
 					break;
 				}
 
-			case EEOP_SQLVALUEFUNCTION:
-				build_EvalXFunc(b, mod, "ExecEvalSQLValueFunction",
-								v_state, op);
-				LLVMBuildBr(b, opblocks[opno + 1]);
-				break;
-
 			case EEOP_CURRENTOFEXPR:
 				build_EvalXFunc(b, mod, "ExecEvalCurrentOfExpr",
 								v_state, op);
diff --git a/src/backend/jit/llvm/llvmjit_types.c b/src/backend/jit/llvm/llvmjit_types.c
index 90ac6b83b5..5b416c5642 100644
--- a/src/backend/jit/llvm/llvmjit_types.c
+++ b/src/backend/jit/llvm/llvmjit_types.c
@@ -126,7 +126,6 @@ void	   *referenced_functions[] =
 	ExecEvalRow,
 	ExecEvalRowNotNull,
 	ExecEvalRowNull,
-	ExecEvalSQLValueFunction,
 	ExecEvalScalarArrayOp,
 	ExecEvalHashedScalarArrayOp,
 	ExecEvalSubPlan,
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 2585a3175c..af8620ceb7 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -210,9 +210,6 @@ exprType(const Node *expr)
 		case T_MinMaxExpr:
 			type = ((const MinMaxExpr *) expr)->minmaxtype;
 			break;
-		case T_SQLValueFunction:
-			type = ((const SQLValueFunction *) expr)->type;
-			break;
 		case T_XmlExpr:
 			if (((const XmlExpr *) expr)->op == IS_DOCUMENT)
 				type = BOOLOID;
@@ -474,8 +471,6 @@ exprTypmod(const Node *expr)
 				return typmod;
 			}
 			break;
-		case T_SQLValueFunction:
-			return ((const SQLValueFunction *) expr)->typmod;
 		case T_CoerceToDomain:
 			return ((const CoerceToDomain *) expr)->resulttypmod;
 		case T_CoerceToDomainValue:
@@ -916,10 +911,6 @@ exprCollation(const Node *expr)
 		case T_MinMaxExpr:
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
-		case T_SQLValueFunction:
-			/* Returns a non-collatable type */
-			coll = InvalidOid;
-			break;
 		case T_XmlExpr:
 
 			/*
@@ -1140,9 +1131,6 @@ exprSetCollation(Node *expr, Oid collation)
 		case T_MinMaxExpr:
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
-		case T_SQLValueFunction:
-			Assert(collation == InvalidOid);
-			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
 				   (collation == DEFAULT_COLLATION_OID) :
@@ -1426,10 +1414,6 @@ exprLocation(const Node *expr)
 			/* GREATEST/LEAST keyword should always be the first thing */
 			loc = ((const MinMaxExpr *) expr)->location;
 			break;
-		case T_SQLValueFunction:
-			/* function keyword should always be the first thing */
-			loc = ((const SQLValueFunction *) expr)->location;
-			break;
 		case T_XmlExpr:
 			{
 				const XmlExpr *xexpr = (const XmlExpr *) expr;
@@ -1717,10 +1701,10 @@ set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
  * for themselves, in case additional checks should be made, or because they
  * have special rules about which parts of the tree need to be visited.
  *
- * Note: we ignore MinMaxExpr, SQLValueFunction, XmlExpr, CoerceToDomain,
- * and NextValueExpr nodes, because they do not contain SQL function OIDs.
- * However, they can invoke SQL-visible functions, so callers should take
- * thought about how to treat them.
+ * Note: we ignore MinMaxExpr, XmlExpr, CoerceToDomain, and NextValueExpr
+ * nodes, because they do not contain SQL function OIDs.  However, they can
+ * invoke SQL-visible functions, so callers should take thought about how
+ * to treat them.
  */
 bool
 check_functions_in_node(Node *node, check_function_callback checker,
@@ -1936,7 +1920,6 @@ expression_tree_walker_impl(Node *node,
 		case T_Const:
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -2673,7 +2656,6 @@ expression_tree_mutator_impl(Node *node,
 			break;
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -3587,7 +3569,6 @@ raw_expression_tree_walker_impl(Node *node,
 	{
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
-		case T_SQLValueFunction:
 		case T_Integer:
 		case T_Float:
 		case T_Boolean:
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 4c6b1d1f55..897309d7ec 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -4603,7 +4603,6 @@ cost_qual_eval_walker(Node *node, cost_qual_eval_context *context)
 		}
 	}
 	else if (IsA(node, MinMaxExpr) ||
-			 IsA(node, SQLValueFunction) ||
 			 IsA(node, XmlExpr) ||
 			 IsA(node, CoerceToDomain) ||
 			 IsA(node, NextValueExpr))
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 7fb32a0710..5db6574bfb 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -382,12 +382,6 @@ contain_mutable_functions_walker(Node *node, void *context)
 								context))
 		return true;
 
-	if (IsA(node, SQLValueFunction))
-	{
-		/* all variants of SQLValueFunction are stable */
-		return true;
-	}
-
 	if (IsA(node, NextValueExpr))
 	{
 		/* NextValueExpr is volatile */
@@ -536,8 +530,8 @@ contain_volatile_functions_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.
 	 */
 
 	/* Recurse to check arguments */
@@ -582,10 +576,9 @@ contain_volatile_functions_not_nextval_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
-	 * Also, since we're intentionally ignoring nextval(), presumably we
-	 * should ignore NextValueExpr.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.  Also, since we're intentionally
+	 * ignoring nextval(), presumably we should ignore NextValueExpr.
 	 */
 
 	/* Recurse to check arguments */
@@ -731,8 +724,8 @@ max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
 	 * (Note: in principle that's wrong because a domain constraint could
 	 * contain a parallel-unsafe function; but useful constraints probably
 	 * never would have such, and assuming they do would cripple use of
-	 * parallel query in the presence of domain types.)  SQLValueFunction
-	 * should be safe in all cases.  NextValueExpr is parallel-unsafe.
+	 * parallel query in the presence of domain types.)  NextValueExpr is
+	 * parallel-unsafe.
 	 */
 	if (IsA(node, CoerceToDomain))
 	{
@@ -1179,7 +1172,6 @@ contain_leaked_vars_walker(Node *node, void *context)
 		case T_CaseExpr:
 		case T_CaseTestExpr:
 		case T_RowExpr:
-		case T_SQLValueFunction:
 		case T_NullTest:
 		case T_BooleanTest:
 		case T_NextValueExpr:
@@ -3149,23 +3141,6 @@ eval_const_expressions_mutator(Node *node,
 				newcoalesce->location = coalesceexpr->location;
 				return (Node *) newcoalesce;
 			}
-		case T_SQLValueFunction:
-			{
-				/*
-				 * All variants of SQLValueFunction are stable, so if we are
-				 * estimating the expression's value, we should evaluate the
-				 * current function value.  Otherwise just copy.
-				 */
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				if (context->estimate)
-					return (Node *) evaluate_expr((Expr *) svf,
-												  svf->type,
-												  svf->typmod,
-												  InvalidOid);
-				else
-					return copyObject((Node *) svf);
-			}
 		case T_FieldSelect:
 			{
 				/*
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 605e9ec096..c8f6f942d1 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -198,8 +198,6 @@ static Node *makeAndExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeOrExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeNotExpr(Node *expr, int location);
 static Node *makeAArrayExpr(List *elements, int location);
-static Node *makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod,
-								  int location);
 static Node *makeXmlExpr(XmlExprOp op, char *name, List *named_args,
 						 List *args, int location);
 static List *mergeTableFuncParameters(List *func_args, List *columns);
@@ -15193,39 +15191,66 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_DATE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_DATE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_date"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_ROLE
 				{
@@ -18164,18 +18189,6 @@ makeAArrayExpr(List *elements, int location)
 	return (Node *) n;
 }
 
-static Node *
-makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod, int location)
-{
-	SQLValueFunction *svf = makeNode(SQLValueFunction);
-
-	svf->op = op;
-	/* svf->type will be filled during parse analysis */
-	svf->typmod = typmod;
-	svf->location = location;
-	return (Node *) svf;
-}
-
 static Node *
 makeXmlExpr(XmlExprOp op, char *name, List *named_args, List *args,
 			int location)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 0fdbf82f3a..150a8099c2 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -61,8 +61,6 @@ static Node *transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 static Node *transformRowExpr(ParseState *pstate, RowExpr *r, bool allowDefault);
 static Node *transformCoalesceExpr(ParseState *pstate, CoalesceExpr *c);
 static Node *transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m);
-static Node *transformSQLValueFunction(ParseState *pstate,
-									   SQLValueFunction *svf);
 static Node *transformXmlExpr(ParseState *pstate, XmlExpr *x);
 static Node *transformXmlSerialize(ParseState *pstate, XmlSerialize *xs);
 static Node *transformBooleanTest(ParseState *pstate, BooleanTest *b);
@@ -240,11 +238,6 @@ transformExprRecurse(ParseState *pstate, Node *expr)
 			result = transformMinMaxExpr(pstate, (MinMaxExpr *) expr);
 			break;
 
-		case T_SQLValueFunction:
-			result = transformSQLValueFunction(pstate,
-											   (SQLValueFunction *) expr);
-			break;
-
 		case T_XmlExpr:
 			result = transformXmlExpr(pstate, (XmlExpr *) expr);
 			break;
@@ -2191,51 +2184,6 @@ transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m)
 	return (Node *) newm;
 }
 
-static Node *
-transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
-{
-	/*
-	 * All we need to do is insert the correct result type and (where needed)
-	 * validate the typmod, so we just modify the node in-place.
-	 */
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			svf->type = DATEOID;
-			break;
-		case SVFOP_CURRENT_TIME:
-			svf->type = TIMETZOID;
-			break;
-		case SVFOP_CURRENT_TIME_N:
-			svf->type = TIMETZOID;
-			svf->typmod = anytime_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-			svf->type = TIMESTAMPTZOID;
-			break;
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			svf->type = TIMESTAMPTZOID;
-			svf->typmod = anytimestamp_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_LOCALTIME:
-			svf->type = TIMEOID;
-			break;
-		case SVFOP_LOCALTIME_N:
-			svf->type = TIMEOID;
-			svf->typmod = anytime_typmod_check(false, svf->typmod);
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-			svf->type = TIMESTAMPOID;
-			break;
-		case SVFOP_LOCALTIMESTAMP_N:
-			svf->type = TIMESTAMPOID;
-			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
-			break;
-	}
-
-	return (Node *) svf;
-}
-
 static Node *
 transformXmlExpr(ParseState *pstate, XmlExpr *x)
 {
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index f54591a987..8e0d6fd01f 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1872,31 +1872,6 @@ FigureColnameInternal(Node *node, char **name)
 					return 2;
 			}
 			break;
-		case T_SQLValueFunction:
-			/* make these act like a function or variable */
-			switch (((SQLValueFunction *) node)->op)
-			{
-				case SVFOP_CURRENT_DATE:
-					*name = "current_date";
-					return 2;
-				case SVFOP_CURRENT_TIME:
-				case SVFOP_CURRENT_TIME_N:
-					*name = "current_time";
-					return 2;
-				case SVFOP_CURRENT_TIMESTAMP:
-				case SVFOP_CURRENT_TIMESTAMP_N:
-					*name = "current_timestamp";
-					return 2;
-				case SVFOP_LOCALTIME:
-				case SVFOP_LOCALTIME_N:
-					*name = "localtime";
-					return 2;
-				case SVFOP_LOCALTIMESTAMP:
-				case SVFOP_LOCALTIMESTAMP_N:
-					*name = "localtimestamp";
-					return 2;
-			}
-			break;
 		case T_XmlExpr:
 			/* make SQL/XML functions act like a regular function */
 			switch (((XmlExpr *) node)->op)
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index a2bdde0459..10c11e00db 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -46,27 +46,6 @@
 
 /* common code for timetypmodin and timetztypmodin */
 static int32
-anytime_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIME
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytime_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytime_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -87,6 +66,26 @@ anytime_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytime_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIME
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytime_typmod_check(istz, tl[0]);
+}
+
 /* common code for timetypmodout and timetztypmodout */
 static char *
 anytime_typmodout(bool istz, int32 typmod)
@@ -296,10 +295,10 @@ EncodeSpecialDate(DateADT dt, char *str)
 
 
 /*
- * GetSQLCurrentDate -- implements CURRENT_DATE
+ * current_date -- implements CURRENT_DATE
  */
-DateADT
-GetSQLCurrentDate(void)
+Datum
+current_date(PG_FUNCTION_ARGS)
 {
 	struct pg_tm tm;
 
@@ -325,46 +324,62 @@ GetSQLCurrentDate(void)
 		cache_mday = tm.tm_mday;
 	}
 
-	return cache_date;
+	return DateADTGetDatum(cache_date);
 }
 
 /*
- * GetSQLCurrentTime -- implements CURRENT_TIME, CURRENT_TIME(n)
+ * current_time -- implements CURRENT_TIME, CURRENT_TIME(n)
  */
-TimeTzADT *
-GetSQLCurrentTime(int32 typmod)
+Datum
+current_time(PG_FUNCTION_ARGS)
 {
 	TimeTzADT  *result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(true, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	result = (TimeTzADT *) palloc(sizeof(TimeTzADT));
 	tm2timetz(tm, fsec, tz, result);
 	AdjustTimeForTypmod(&(result->time), typmod);
-	return result;
+
+	return TimeTzADTPGetDatum(result);
 }
 
 /*
- * GetSQLLocalTime -- implements LOCALTIME, LOCALTIME(n)
+ * sql_localtime -- implements LOCALTIME, LOCALTIME(n)
  */
-TimeADT
-GetSQLLocalTime(int32 typmod)
+Datum
+sql_localtime(PG_FUNCTION_ARGS)
 {
 	TimeADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(false, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	tm2time(tm, fsec, &result);
 	AdjustTimeForTypmod(&result, typmod);
-	return result;
+
+	return TimeADTGetDatum(result);
 }
 
 
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index f95289f11c..48ad54ecf1 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8180,7 +8180,6 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
 		case T_RowExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 		case T_NextValueExpr:
 		case T_NullIfExpr:
@@ -9160,49 +9159,6 @@ get_rule_expr(Node *node, deparse_context *context,
 			}
 			break;
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				/*
-				 * Note: this code knows that typmod for time, timestamp, and
-				 * timestamptz just prints as integer.
-				 */
-				switch (svf->op)
-				{
-					case SVFOP_CURRENT_DATE:
-						appendStringInfoString(buf, "CURRENT_DATE");
-						break;
-					case SVFOP_CURRENT_TIME:
-						appendStringInfoString(buf, "CURRENT_TIME");
-						break;
-					case SVFOP_CURRENT_TIME_N:
-						appendStringInfo(buf, "CURRENT_TIME(%d)", svf->typmod);
-						break;
-					case SVFOP_CURRENT_TIMESTAMP:
-						appendStringInfoString(buf, "CURRENT_TIMESTAMP");
-						break;
-					case SVFOP_CURRENT_TIMESTAMP_N:
-						appendStringInfo(buf, "CURRENT_TIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-					case SVFOP_LOCALTIME:
-						appendStringInfoString(buf, "LOCALTIME");
-						break;
-					case SVFOP_LOCALTIME_N:
-						appendStringInfo(buf, "LOCALTIME(%d)", svf->typmod);
-						break;
-					case SVFOP_LOCALTIMESTAMP:
-						appendStringInfoString(buf, "LOCALTIMESTAMP");
-						break;
-					case SVFOP_LOCALTIMESTAMP_N:
-						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-				}
-			}
-			break;
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
@@ -9728,7 +9684,6 @@ looks_like_function(Node *node)
 		case T_NullIfExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 			/* these are all accepted by func_expr_common_subexpr */
 			return true;
@@ -10322,6 +10277,70 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
 
+		case F_CURRENT_DATE:
+			appendStringInfoString(buf, "CURRENT_DATE");
+			return true;
+		case F_CURRENT_TIME:
+			appendStringInfoString(buf, "CURRENT_TIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_CURRENT_TIMESTAMP:
+			appendStringInfoString(buf, "CURRENT_TIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIME:
+			appendStringInfoString(buf, "LOCALTIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIMESTAMP:
+			appendStringInfoString(buf, "LOCALTIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+
 		case F_XMLEXISTS:
 			/* XMLEXISTS ... extra parens because args are c_expr */
 			appendStringInfoString(buf, "XMLEXISTS((");
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index d8552a1f18..ef92323fd0 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -81,27 +81,6 @@ static Timestamp timestamptz2timestamp(TimestampTz timestamp);
 
 /* common code for timestamptypmodin and timestamptztypmodin */
 static int32
-anytimestamp_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIMESTAMP
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytimestamp_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytimestamp_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -122,6 +101,26 @@ anytimestamp_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytimestamp_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIMESTAMP
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytimestamp_typmod_check(istz, tl[0]);
+}
+
 /* common code for timestamptypmodout and timestamptztypmodout */
 static char *
 anytimestamp_typmodout(bool istz, int32 typmod)
@@ -1586,33 +1585,48 @@ GetCurrentTimestamp(void)
 }
 
 /*
- * GetSQLCurrentTimestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
+ * current_timestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
  */
-TimestampTz
-GetSQLCurrentTimestamp(int32 typmod)
+Datum
+current_timestamp(PG_FUNCTION_ARGS)
 {
 	TimestampTz ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(true, typmod);
+	}
 
 	ts = GetCurrentTransactionStartTimestamp();
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampTzGetDatum(ts);
 }
 
 /*
- * GetSQLLocalTimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
+ * sql_localtimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
  */
-Timestamp
-GetSQLLocalTimestamp(int32 typmod)
+Datum
+sql_localtimestamp(PG_FUNCTION_ARGS)
 {
 	Timestamp	ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(false, typmod);
+	}
 
 	ts = timestamptz2timestamp(GetCurrentTransactionStartTimestamp());
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampGetDatum(ts);
 }
 
+
 /*
  * timeofday(*) -- returns the current time as a text.
  */
diff --git a/src/backend/utils/misc/queryjumble.c b/src/backend/utils/misc/queryjumble.c
index a8508463e7..0ace74de78 100644
--- a/src/backend/utils/misc/queryjumble.c
+++ b/src/backend/utils/misc/queryjumble.c
@@ -606,15 +606,6 @@ JumbleExpr(JumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) mmexpr->args);
 			}
 			break;
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				APP_JUMB(svf->op);
-				/* type is fully determined by op */
-				APP_JUMB(svf->typmod);
-			}
-			break;
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 5bf39fd9aa..28a20900f1 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -2,7 +2,7 @@
 -- expression evaluation tests that don't fit into a more specific file
 --
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 -- current_date  (always matches because of transactional behaviour)
 SELECT date(now())::text = current_date::text;
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index 0e163cc0d7..f9a0299d17 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -3,7 +3,7 @@
 --
 
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 
 
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 2f02cc8f42..e45a14b60c 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2397,8 +2397,6 @@ SQLFunctionCache
 SQLFunctionCachePtr
 SQLFunctionParseInfo
 SQLFunctionParseInfoPtr
-SQLValueFunction
-SQLValueFunctionOp
 SSL
 SSLExtensionInfoContext
 SSL_CTX
-- 
2.37.2

From 3611cfa6f0171dcd65eeb88461f4c48989cd3f1a Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Sun, 20 Nov 2022 11:53:28 +0900
Subject: [PATCH v4] Replace SQLValueFunction by direct function calls

This impacts 9 patterns where the SQL grammar takes priority:
- localtime, that can take a typmod.
- localtimestamp, that can take a typmod.
- current_time, that can take a typmod.
- current_timestamp, that can take a typmod.
- current_date.

Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to keep compatibility (when a keyword is specified in a
SELECT or in a FROM clause without an alias), with tests to cover all
that.

XXX: bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/pg_proc.dat           |  15 +++
 src/include/executor/execExpr.h           |   8 --
 src/include/nodes/primnodes.h             |  33 -------
 src/include/utils/date.h                  |   4 -
 src/include/utils/timestamp.h             |   4 -
 src/backend/catalog/system_functions.sql  |  26 ++++++
 src/backend/executor/execExpr.c           |  11 ---
 src/backend/executor/execExprInterp.c     |  46 ---------
 src/backend/jit/llvm/llvmjit_expr.c       |   6 --
 src/backend/jit/llvm/llvmjit_types.c      |   1 -
 src/backend/nodes/nodeFuncs.c             |  27 +-----
 src/backend/optimizer/path/costsize.c     |   1 -
 src/backend/optimizer/util/clauses.c      |  39 ++------
 src/backend/parser/gram.y                 |  59 +++++++-----
 src/backend/parser/parse_expr.c           |  52 -----------
 src/backend/parser/parse_target.c         |  25 -----
 src/backend/utils/adt/date.c              |  81 +++++++++-------
 src/backend/utils/adt/ruleutils.c         | 109 +++++++++++++---------
 src/backend/utils/adt/timestamp.c         |  72 ++++++++------
 src/backend/utils/misc/queryjumble.c      |   9 --
 src/test/regress/expected/expressions.out |   2 +-
 src/test/regress/sql/expressions.sql      |   2 +-
 src/tools/pgindent/typedefs.list          |   2 -
 23 files changed, 245 insertions(+), 389 deletions(-)

diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index fd2559442e..35dc369728 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1520,6 +1520,21 @@
 { oid => '9977', descr => 'system user name',
   proname => 'system_user', provolatile => 's', prorettype => 'text',
   proargtypes => '', prosrc => 'system_user' },
+{ oid => '9978', descr => 'current date',
+  proname => 'current_date', provolatile => 's', prorettype => 'date',
+  proargtypes => '', prosrc => 'current_date' },
+{ oid => '9979', descr => 'current time',
+  proname => 'current_time', provolatile => 's', prorettype => 'timetz',
+  proargtypes => 'int4', prosrc => 'current_time', proisstrict => 'f' },
+{ oid => '9980', descr => 'current timestamp',
+  proname => 'current_timestamp', provolatile => 's', prorettype => 'timestamptz',
+  proargtypes => 'int4', prosrc => 'current_timestamp', proisstrict => 'f' },
+{ oid => '9981', descr => 'local time',
+  proname => 'localtime', provolatile => 's', prorettype => 'time',
+  proargtypes => 'int4', prosrc => 'sql_localtime', proisstrict => 'f' },
+{ oid => '9982', descr => 'local timestamp',
+  proname => 'localtimestamp', provolatile => 's', prorettype => 'timestamp',
+  proargtypes => 'int4', prosrc => 'sql_localtimestamp', proisstrict => 'f' },
 
 { oid => '744',
   proname => 'array_eq', prorettype => 'bool',
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index e14f15d435..0557302b92 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -170,7 +170,6 @@ typedef enum ExprEvalOp
 	EEOP_DISTINCT,
 	EEOP_NOT_DISTINCT,
 	EEOP_NULLIF,
-	EEOP_SQLVALUEFUNCTION,
 	EEOP_CURRENTOFEXPR,
 	EEOP_NEXTVALUEEXPR,
 	EEOP_ARRAYEXPR,
@@ -416,12 +415,6 @@ typedef struct ExprEvalStep
 			FunctionCallInfo fcinfo_data_in;
 		}			iocoerce;
 
-		/* for EEOP_SQLVALUEFUNCTION */
-		struct
-		{
-			SQLValueFunction *svf;
-		}			sqlvaluefunction;
-
 		/* for EEOP_NEXTVALUEEXPR */
 		struct
 		{
@@ -741,7 +734,6 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op,
 							  ExprContext *econtext);
 extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op,
 								ExprContext *econtext);
-extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalRowNull(ExprState *state, ExprEvalStep *op,
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index f6dd27edcc..74f228d959 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1292,39 +1292,6 @@ typedef struct MinMaxExpr
 	int			location;		/* token location, or -1 if unknown */
 } MinMaxExpr;
 
-/*
- * SQLValueFunction - parameterless functions with special grammar productions
- *
- * The SQL standard categorizes some of these as <datetime value function>
- * and others as <general value specification>.  We call 'em SQLValueFunctions
- * for lack of a better term.  We store type and typmod of the result so that
- * some code doesn't need to know each function individually, and because
- * we would need to store typmod anyway for some of the datetime functions.
- * Note that currently, all variants return non-collating datatypes, so we do
- * not need a collation field; also, all these functions are stable.
- */
-typedef enum SQLValueFunctionOp
-{
-	SVFOP_CURRENT_DATE,
-	SVFOP_CURRENT_TIME,
-	SVFOP_CURRENT_TIME_N,
-	SVFOP_CURRENT_TIMESTAMP,
-	SVFOP_CURRENT_TIMESTAMP_N,
-	SVFOP_LOCALTIME,
-	SVFOP_LOCALTIME_N,
-	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N
-} SQLValueFunctionOp;
-
-typedef struct SQLValueFunction
-{
-	Expr		xpr;
-	SQLValueFunctionOp op;		/* which function this is */
-	Oid			type;			/* result type/typmod */
-	int32		typmod;
-	int			location;		/* token location, or -1 if unknown */
-} SQLValueFunction;
-
 /*
  * XmlExpr - various SQL/XML functions requiring special grammar productions
  *
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index 0bbe889128..fad4878722 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -96,7 +96,6 @@ TimeTzADTPGetDatum(const TimeTzADT *X)
 
 
 /* date.c */
-extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
@@ -104,9 +103,6 @@ extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
 extern void EncodeSpecialDate(DateADT dt, char *str);
-extern DateADT GetSQLCurrentDate(void);
-extern TimeTzADT *GetSQLCurrentTime(int32 typmod);
-extern TimeADT GetSQLLocalTime(int32 typmod);
 extern int	time2tm(TimeADT time, struct pg_tm *tm, fsec_t *fsec);
 extern int	timetz2tm(TimeTzADT *time, struct pg_tm *tm, fsec_t *fsec, int *tzp);
 extern int	tm2time(struct pg_tm *tm, fsec_t fsec, TimeADT *result);
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 76b7b4a3ca..7fd0b58825 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -93,11 +93,7 @@ extern PGDLLIMPORT TimestampTz PgReloadTime;
 
 /* Internal routines (not fmgr-callable) */
 
-extern int32 anytimestamp_typmod_check(bool istz, int32 typmod);
-
 extern TimestampTz GetCurrentTimestamp(void);
-extern TimestampTz GetSQLCurrentTimestamp(int32 typmod);
-extern Timestamp GetSQLLocalTimestamp(int32 typmod);
 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 								long *secs, int *microsecs);
 extern long TimestampDifferenceMilliseconds(TimestampTz start_time,
diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 30a048f6b0..4c3b4c3f8e 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -594,6 +594,32 @@ LANGUAGE internal
 STRICT IMMUTABLE PARALLEL SAFE
 AS 'unicode_is_normalized';
 
+-- Functions with SQL-mandated special syntax and some defaults.
+CREATE OR REPLACE FUNCTION
+  "current_time"(int4 DEFAULT NULL)
+RETURNS timetz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_time';
+CREATE OR REPLACE FUNCTION
+  "current_timestamp"(int4 DEFAULT NULL)
+RETURNS timestamptz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_timestamp';
+CREATE OR REPLACE FUNCTION
+  "localtime"(int4 DEFAULT NULL)
+RETURNS time
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtime';
+CREATE OR REPLACE FUNCTION
+  "localtimestamp"(int4 DEFAULT NULL)
+RETURNS timestamp
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtimestamp';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 0ecb2f8610..81429b9f05 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -2210,17 +2210,6 @@ ExecInitExprRec(Expr *node, ExprState *state,
 				break;
 			}
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				scratch.opcode = EEOP_SQLVALUEFUNCTION;
-				scratch.d.sqlvaluefunction.svf = svf;
-
-				ExprEvalPushStep(state, &scratch);
-				break;
-			}
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 6ebf5c287e..1dab2787b7 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -452,7 +452,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 		&&CASE_EEOP_DISTINCT,
 		&&CASE_EEOP_NOT_DISTINCT,
 		&&CASE_EEOP_NULLIF,
-		&&CASE_EEOP_SQLVALUEFUNCTION,
 		&&CASE_EEOP_CURRENTOFEXPR,
 		&&CASE_EEOP_NEXTVALUEEXPR,
 		&&CASE_EEOP_ARRAYEXPR,
@@ -1301,17 +1300,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 			EEO_NEXT();
 		}
 
-		EEO_CASE(EEOP_SQLVALUEFUNCTION)
-		{
-			/*
-			 * Doesn't seem worthwhile to have an inline implementation
-			 * efficiency-wise.
-			 */
-			ExecEvalSQLValueFunction(state, op);
-
-			EEO_NEXT();
-		}
-
 		EEO_CASE(EEOP_CURRENTOFEXPR)
 		{
 			/* error invocation uses space, and shouldn't ever occur */
@@ -2489,40 +2477,6 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 			 errmsg("no value found for parameter %d", paramId)));
 }
 
-/*
- * Evaluate a SQLValueFunction expression.
- */
-void
-ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
-{
-	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
-
-	*op->resnull = false;
-
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			*op->resvalue = DateADTGetDatum(GetSQLCurrentDate());
-			break;
-		case SVFOP_CURRENT_TIME:
-		case SVFOP_CURRENT_TIME_N:
-			*op->resvalue = TimeTzADTPGetDatum(GetSQLCurrentTime(svf->typmod));
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			*op->resvalue = TimestampTzGetDatum(GetSQLCurrentTimestamp(svf->typmod));
-			break;
-		case SVFOP_LOCALTIME:
-		case SVFOP_LOCALTIME_N:
-			*op->resvalue = TimeADTGetDatum(GetSQLLocalTime(svf->typmod));
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-		case SVFOP_LOCALTIMESTAMP_N:
-			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
-			break;
-	}
-}
-
 /*
  * Raise error if a CURRENT OF expression is evaluated.
  *
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index 95d0807bdd..f114337f8e 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -1549,12 +1549,6 @@ llvm_compile_expr(ExprState *state)
 					break;
 				}
 
-			case EEOP_SQLVALUEFUNCTION:
-				build_EvalXFunc(b, mod, "ExecEvalSQLValueFunction",
-								v_state, op);
-				LLVMBuildBr(b, opblocks[opno + 1]);
-				break;
-
 			case EEOP_CURRENTOFEXPR:
 				build_EvalXFunc(b, mod, "ExecEvalCurrentOfExpr",
 								v_state, op);
diff --git a/src/backend/jit/llvm/llvmjit_types.c b/src/backend/jit/llvm/llvmjit_types.c
index 90ac6b83b5..5b416c5642 100644
--- a/src/backend/jit/llvm/llvmjit_types.c
+++ b/src/backend/jit/llvm/llvmjit_types.c
@@ -126,7 +126,6 @@ void	   *referenced_functions[] =
 	ExecEvalRow,
 	ExecEvalRowNotNull,
 	ExecEvalRowNull,
-	ExecEvalSQLValueFunction,
 	ExecEvalScalarArrayOp,
 	ExecEvalHashedScalarArrayOp,
 	ExecEvalSubPlan,
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 2585a3175c..af8620ceb7 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -210,9 +210,6 @@ exprType(const Node *expr)
 		case T_MinMaxExpr:
 			type = ((const MinMaxExpr *) expr)->minmaxtype;
 			break;
-		case T_SQLValueFunction:
-			type = ((const SQLValueFunction *) expr)->type;
-			break;
 		case T_XmlExpr:
 			if (((const XmlExpr *) expr)->op == IS_DOCUMENT)
 				type = BOOLOID;
@@ -474,8 +471,6 @@ exprTypmod(const Node *expr)
 				return typmod;
 			}
 			break;
-		case T_SQLValueFunction:
-			return ((const SQLValueFunction *) expr)->typmod;
 		case T_CoerceToDomain:
 			return ((const CoerceToDomain *) expr)->resulttypmod;
 		case T_CoerceToDomainValue:
@@ -916,10 +911,6 @@ exprCollation(const Node *expr)
 		case T_MinMaxExpr:
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
-		case T_SQLValueFunction:
-			/* Returns a non-collatable type */
-			coll = InvalidOid;
-			break;
 		case T_XmlExpr:
 
 			/*
@@ -1140,9 +1131,6 @@ exprSetCollation(Node *expr, Oid collation)
 		case T_MinMaxExpr:
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
-		case T_SQLValueFunction:
-			Assert(collation == InvalidOid);
-			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
 				   (collation == DEFAULT_COLLATION_OID) :
@@ -1426,10 +1414,6 @@ exprLocation(const Node *expr)
 			/* GREATEST/LEAST keyword should always be the first thing */
 			loc = ((const MinMaxExpr *) expr)->location;
 			break;
-		case T_SQLValueFunction:
-			/* function keyword should always be the first thing */
-			loc = ((const SQLValueFunction *) expr)->location;
-			break;
 		case T_XmlExpr:
 			{
 				const XmlExpr *xexpr = (const XmlExpr *) expr;
@@ -1717,10 +1701,10 @@ set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
  * for themselves, in case additional checks should be made, or because they
  * have special rules about which parts of the tree need to be visited.
  *
- * Note: we ignore MinMaxExpr, SQLValueFunction, XmlExpr, CoerceToDomain,
- * and NextValueExpr nodes, because they do not contain SQL function OIDs.
- * However, they can invoke SQL-visible functions, so callers should take
- * thought about how to treat them.
+ * Note: we ignore MinMaxExpr, XmlExpr, CoerceToDomain, and NextValueExpr
+ * nodes, because they do not contain SQL function OIDs.  However, they can
+ * invoke SQL-visible functions, so callers should take thought about how
+ * to treat them.
  */
 bool
 check_functions_in_node(Node *node, check_function_callback checker,
@@ -1936,7 +1920,6 @@ expression_tree_walker_impl(Node *node,
 		case T_Const:
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -2673,7 +2656,6 @@ expression_tree_mutator_impl(Node *node,
 			break;
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -3587,7 +3569,6 @@ raw_expression_tree_walker_impl(Node *node,
 	{
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
-		case T_SQLValueFunction:
 		case T_Integer:
 		case T_Float:
 		case T_Boolean:
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 4c6b1d1f55..897309d7ec 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -4603,7 +4603,6 @@ cost_qual_eval_walker(Node *node, cost_qual_eval_context *context)
 		}
 	}
 	else if (IsA(node, MinMaxExpr) ||
-			 IsA(node, SQLValueFunction) ||
 			 IsA(node, XmlExpr) ||
 			 IsA(node, CoerceToDomain) ||
 			 IsA(node, NextValueExpr))
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 33790a4f46..c61d9c68a0 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -383,12 +383,6 @@ contain_mutable_functions_walker(Node *node, void *context)
 								context))
 		return true;
 
-	if (IsA(node, SQLValueFunction))
-	{
-		/* all variants of SQLValueFunction are stable */
-		return true;
-	}
-
 	if (IsA(node, NextValueExpr))
 	{
 		/* NextValueExpr is volatile */
@@ -537,8 +531,8 @@ contain_volatile_functions_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.
 	 */
 
 	/* Recurse to check arguments */
@@ -583,10 +577,9 @@ contain_volatile_functions_not_nextval_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
-	 * Also, since we're intentionally ignoring nextval(), presumably we
-	 * should ignore NextValueExpr.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.  Also, since we're intentionally
+	 * ignoring nextval(), presumably we should ignore NextValueExpr.
 	 */
 
 	/* Recurse to check arguments */
@@ -732,8 +725,8 @@ max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
 	 * (Note: in principle that's wrong because a domain constraint could
 	 * contain a parallel-unsafe function; but useful constraints probably
 	 * never would have such, and assuming they do would cripple use of
-	 * parallel query in the presence of domain types.)  SQLValueFunction
-	 * should be safe in all cases.  NextValueExpr is parallel-unsafe.
+	 * parallel query in the presence of domain types.)  NextValueExpr is
+	 * parallel-unsafe.
 	 */
 	if (IsA(node, CoerceToDomain))
 	{
@@ -1180,7 +1173,6 @@ contain_leaked_vars_walker(Node *node, void *context)
 		case T_CaseExpr:
 		case T_CaseTestExpr:
 		case T_RowExpr:
-		case T_SQLValueFunction:
 		case T_NullTest:
 		case T_BooleanTest:
 		case T_NextValueExpr:
@@ -3194,23 +3186,6 @@ eval_const_expressions_mutator(Node *node,
 				newcoalesce->location = coalesceexpr->location;
 				return (Node *) newcoalesce;
 			}
-		case T_SQLValueFunction:
-			{
-				/*
-				 * All variants of SQLValueFunction are stable, so if we are
-				 * estimating the expression's value, we should evaluate the
-				 * current function value.  Otherwise just copy.
-				 */
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				if (context->estimate)
-					return (Node *) evaluate_expr((Expr *) svf,
-												  svf->type,
-												  svf->typmod,
-												  InvalidOid);
-				else
-					return copyObject((Node *) svf);
-			}
 		case T_FieldSelect:
 			{
 				/*
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 9054742427..9384214942 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -198,8 +198,6 @@ static Node *makeAndExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeOrExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeNotExpr(Node *expr, int location);
 static Node *makeAArrayExpr(List *elements, int location);
-static Node *makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod,
-								  int location);
 static Node *makeXmlExpr(XmlExprOp op, char *name, List *named_args,
 						 List *args, int location);
 static List *mergeTableFuncParameters(List *func_args, List *columns);
@@ -15195,39 +15193,66 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_DATE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_DATE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_date"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_ROLE
 				{
@@ -18166,18 +18191,6 @@ makeAArrayExpr(List *elements, int location)
 	return (Node *) n;
 }
 
-static Node *
-makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod, int location)
-{
-	SQLValueFunction *svf = makeNode(SQLValueFunction);
-
-	svf->op = op;
-	/* svf->type will be filled during parse analysis */
-	svf->typmod = typmod;
-	svf->location = location;
-	return (Node *) svf;
-}
-
 static Node *
 makeXmlExpr(XmlExprOp op, char *name, List *named_args, List *args,
 			int location)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 0fdbf82f3a..150a8099c2 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -61,8 +61,6 @@ static Node *transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 static Node *transformRowExpr(ParseState *pstate, RowExpr *r, bool allowDefault);
 static Node *transformCoalesceExpr(ParseState *pstate, CoalesceExpr *c);
 static Node *transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m);
-static Node *transformSQLValueFunction(ParseState *pstate,
-									   SQLValueFunction *svf);
 static Node *transformXmlExpr(ParseState *pstate, XmlExpr *x);
 static Node *transformXmlSerialize(ParseState *pstate, XmlSerialize *xs);
 static Node *transformBooleanTest(ParseState *pstate, BooleanTest *b);
@@ -240,11 +238,6 @@ transformExprRecurse(ParseState *pstate, Node *expr)
 			result = transformMinMaxExpr(pstate, (MinMaxExpr *) expr);
 			break;
 
-		case T_SQLValueFunction:
-			result = transformSQLValueFunction(pstate,
-											   (SQLValueFunction *) expr);
-			break;
-
 		case T_XmlExpr:
 			result = transformXmlExpr(pstate, (XmlExpr *) expr);
 			break;
@@ -2191,51 +2184,6 @@ transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m)
 	return (Node *) newm;
 }
 
-static Node *
-transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
-{
-	/*
-	 * All we need to do is insert the correct result type and (where needed)
-	 * validate the typmod, so we just modify the node in-place.
-	 */
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			svf->type = DATEOID;
-			break;
-		case SVFOP_CURRENT_TIME:
-			svf->type = TIMETZOID;
-			break;
-		case SVFOP_CURRENT_TIME_N:
-			svf->type = TIMETZOID;
-			svf->typmod = anytime_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-			svf->type = TIMESTAMPTZOID;
-			break;
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			svf->type = TIMESTAMPTZOID;
-			svf->typmod = anytimestamp_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_LOCALTIME:
-			svf->type = TIMEOID;
-			break;
-		case SVFOP_LOCALTIME_N:
-			svf->type = TIMEOID;
-			svf->typmod = anytime_typmod_check(false, svf->typmod);
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-			svf->type = TIMESTAMPOID;
-			break;
-		case SVFOP_LOCALTIMESTAMP_N:
-			svf->type = TIMESTAMPOID;
-			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
-			break;
-	}
-
-	return (Node *) svf;
-}
-
 static Node *
 transformXmlExpr(ParseState *pstate, XmlExpr *x)
 {
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index f54591a987..8e0d6fd01f 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1872,31 +1872,6 @@ FigureColnameInternal(Node *node, char **name)
 					return 2;
 			}
 			break;
-		case T_SQLValueFunction:
-			/* make these act like a function or variable */
-			switch (((SQLValueFunction *) node)->op)
-			{
-				case SVFOP_CURRENT_DATE:
-					*name = "current_date";
-					return 2;
-				case SVFOP_CURRENT_TIME:
-				case SVFOP_CURRENT_TIME_N:
-					*name = "current_time";
-					return 2;
-				case SVFOP_CURRENT_TIMESTAMP:
-				case SVFOP_CURRENT_TIMESTAMP_N:
-					*name = "current_timestamp";
-					return 2;
-				case SVFOP_LOCALTIME:
-				case SVFOP_LOCALTIME_N:
-					*name = "localtime";
-					return 2;
-				case SVFOP_LOCALTIMESTAMP:
-				case SVFOP_LOCALTIMESTAMP_N:
-					*name = "localtimestamp";
-					return 2;
-			}
-			break;
 		case T_XmlExpr:
 			/* make SQL/XML functions act like a regular function */
 			switch (((XmlExpr *) node)->op)
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index a2bdde0459..10c11e00db 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -46,27 +46,6 @@
 
 /* common code for timetypmodin and timetztypmodin */
 static int32
-anytime_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIME
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytime_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytime_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -87,6 +66,26 @@ anytime_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytime_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIME
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytime_typmod_check(istz, tl[0]);
+}
+
 /* common code for timetypmodout and timetztypmodout */
 static char *
 anytime_typmodout(bool istz, int32 typmod)
@@ -296,10 +295,10 @@ EncodeSpecialDate(DateADT dt, char *str)
 
 
 /*
- * GetSQLCurrentDate -- implements CURRENT_DATE
+ * current_date -- implements CURRENT_DATE
  */
-DateADT
-GetSQLCurrentDate(void)
+Datum
+current_date(PG_FUNCTION_ARGS)
 {
 	struct pg_tm tm;
 
@@ -325,46 +324,62 @@ GetSQLCurrentDate(void)
 		cache_mday = tm.tm_mday;
 	}
 
-	return cache_date;
+	return DateADTGetDatum(cache_date);
 }
 
 /*
- * GetSQLCurrentTime -- implements CURRENT_TIME, CURRENT_TIME(n)
+ * current_time -- implements CURRENT_TIME, CURRENT_TIME(n)
  */
-TimeTzADT *
-GetSQLCurrentTime(int32 typmod)
+Datum
+current_time(PG_FUNCTION_ARGS)
 {
 	TimeTzADT  *result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(true, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	result = (TimeTzADT *) palloc(sizeof(TimeTzADT));
 	tm2timetz(tm, fsec, tz, result);
 	AdjustTimeForTypmod(&(result->time), typmod);
-	return result;
+
+	return TimeTzADTPGetDatum(result);
 }
 
 /*
- * GetSQLLocalTime -- implements LOCALTIME, LOCALTIME(n)
+ * sql_localtime -- implements LOCALTIME, LOCALTIME(n)
  */
-TimeADT
-GetSQLLocalTime(int32 typmod)
+Datum
+sql_localtime(PG_FUNCTION_ARGS)
 {
 	TimeADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(false, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	tm2time(tm, fsec, &result);
 	AdjustTimeForTypmod(&result, typmod);
-	return result;
+
+	return TimeADTGetDatum(result);
 }
 
 
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 129f3333fb..c00dc5e32e 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8150,7 +8150,6 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
 		case T_RowExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 		case T_NextValueExpr:
 		case T_NullIfExpr:
@@ -9130,49 +9129,6 @@ get_rule_expr(Node *node, deparse_context *context,
 			}
 			break;
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				/*
-				 * Note: this code knows that typmod for time, timestamp, and
-				 * timestamptz just prints as integer.
-				 */
-				switch (svf->op)
-				{
-					case SVFOP_CURRENT_DATE:
-						appendStringInfoString(buf, "CURRENT_DATE");
-						break;
-					case SVFOP_CURRENT_TIME:
-						appendStringInfoString(buf, "CURRENT_TIME");
-						break;
-					case SVFOP_CURRENT_TIME_N:
-						appendStringInfo(buf, "CURRENT_TIME(%d)", svf->typmod);
-						break;
-					case SVFOP_CURRENT_TIMESTAMP:
-						appendStringInfoString(buf, "CURRENT_TIMESTAMP");
-						break;
-					case SVFOP_CURRENT_TIMESTAMP_N:
-						appendStringInfo(buf, "CURRENT_TIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-					case SVFOP_LOCALTIME:
-						appendStringInfoString(buf, "LOCALTIME");
-						break;
-					case SVFOP_LOCALTIME_N:
-						appendStringInfo(buf, "LOCALTIME(%d)", svf->typmod);
-						break;
-					case SVFOP_LOCALTIMESTAMP:
-						appendStringInfoString(buf, "LOCALTIMESTAMP");
-						break;
-					case SVFOP_LOCALTIMESTAMP_N:
-						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-				}
-			}
-			break;
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
@@ -9698,7 +9654,6 @@ looks_like_function(Node *node)
 		case T_NullIfExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 			/* these are all accepted by func_expr_common_subexpr */
 			return true;
@@ -10292,6 +10247,70 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
 
+		case F_CURRENT_DATE:
+			appendStringInfoString(buf, "CURRENT_DATE");
+			return true;
+		case F_CURRENT_TIME:
+			appendStringInfoString(buf, "CURRENT_TIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_CURRENT_TIMESTAMP:
+			appendStringInfoString(buf, "CURRENT_TIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIME:
+			appendStringInfoString(buf, "LOCALTIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIMESTAMP:
+			appendStringInfoString(buf, "LOCALTIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+
 		case F_XMLEXISTS:
 			/* XMLEXISTS ... extra parens because args are c_expr */
 			appendStringInfoString(buf, "XMLEXISTS((");
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index d8552a1f18..ef92323fd0 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -81,27 +81,6 @@ static Timestamp timestamptz2timestamp(TimestampTz timestamp);
 
 /* common code for timestamptypmodin and timestamptztypmodin */
 static int32
-anytimestamp_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIMESTAMP
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytimestamp_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytimestamp_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -122,6 +101,26 @@ anytimestamp_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytimestamp_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIMESTAMP
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytimestamp_typmod_check(istz, tl[0]);
+}
+
 /* common code for timestamptypmodout and timestamptztypmodout */
 static char *
 anytimestamp_typmodout(bool istz, int32 typmod)
@@ -1586,33 +1585,48 @@ GetCurrentTimestamp(void)
 }
 
 /*
- * GetSQLCurrentTimestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
+ * current_timestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
  */
-TimestampTz
-GetSQLCurrentTimestamp(int32 typmod)
+Datum
+current_timestamp(PG_FUNCTION_ARGS)
 {
 	TimestampTz ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(true, typmod);
+	}
 
 	ts = GetCurrentTransactionStartTimestamp();
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampTzGetDatum(ts);
 }
 
 /*
- * GetSQLLocalTimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
+ * sql_localtimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
  */
-Timestamp
-GetSQLLocalTimestamp(int32 typmod)
+Datum
+sql_localtimestamp(PG_FUNCTION_ARGS)
 {
 	Timestamp	ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(false, typmod);
+	}
 
 	ts = timestamptz2timestamp(GetCurrentTransactionStartTimestamp());
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampGetDatum(ts);
 }
 
+
 /*
  * timeofday(*) -- returns the current time as a text.
  */
diff --git a/src/backend/utils/misc/queryjumble.c b/src/backend/utils/misc/queryjumble.c
index a8508463e7..0ace74de78 100644
--- a/src/backend/utils/misc/queryjumble.c
+++ b/src/backend/utils/misc/queryjumble.c
@@ -606,15 +606,6 @@ JumbleExpr(JumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) mmexpr->args);
 			}
 			break;
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				APP_JUMB(svf->op);
-				/* type is fully determined by op */
-				APP_JUMB(svf->typmod);
-			}
-			break;
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 5bf39fd9aa..28a20900f1 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -2,7 +2,7 @@
 -- expression evaluation tests that don't fit into a more specific file
 --
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 -- current_date  (always matches because of transactional behaviour)
 SELECT date(now())::text = current_date::text;
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index 0e163cc0d7..f9a0299d17 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -3,7 +3,7 @@
 --
 
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 
 
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index f8302f1ed1..2f5802195d 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2397,8 +2397,6 @@ SQLFunctionCache
 SQLFunctionCachePtr
 SQLFunctionParseInfo
 SQLFunctionParseInfoPtr
-SQLValueFunction
-SQLValueFunctionOp
 SSL
 SSLExtensionInfoContext
 SSL_CTX
-- 
2.38.1

From 3611cfa6f0171dcd65eeb88461f4c48989cd3f1a Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Sun, 20 Nov 2022 11:53:28 +0900
Subject: [PATCH v5 1/2] Replace SQLValueFunction by direct function calls

This impacts 9 patterns where the SQL grammar takes priority:
- localtime, that can take a typmod.
- localtimestamp, that can take a typmod.
- current_time, that can take a typmod.
- current_timestamp, that can take a typmod.
- current_date.

Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to keep compatibility (when a keyword is specified in a
SELECT or in a FROM clause without an alias), with tests to cover all
that.

XXX: bump catalog version.

Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
---
 src/include/catalog/pg_proc.dat           |  15 +++
 src/include/executor/execExpr.h           |   8 --
 src/include/nodes/primnodes.h             |  33 -------
 src/include/utils/date.h                  |   4 -
 src/include/utils/timestamp.h             |   4 -
 src/backend/catalog/system_functions.sql  |  26 ++++++
 src/backend/executor/execExpr.c           |  11 ---
 src/backend/executor/execExprInterp.c     |  46 ---------
 src/backend/jit/llvm/llvmjit_expr.c       |   6 --
 src/backend/jit/llvm/llvmjit_types.c      |   1 -
 src/backend/nodes/nodeFuncs.c             |  27 +-----
 src/backend/optimizer/path/costsize.c     |   1 -
 src/backend/optimizer/util/clauses.c      |  39 ++------
 src/backend/parser/gram.y                 |  59 +++++++-----
 src/backend/parser/parse_expr.c           |  52 -----------
 src/backend/parser/parse_target.c         |  25 -----
 src/backend/utils/adt/date.c              |  81 +++++++++-------
 src/backend/utils/adt/ruleutils.c         | 109 +++++++++++++---------
 src/backend/utils/adt/timestamp.c         |  72 ++++++++------
 src/backend/utils/misc/queryjumble.c      |   9 --
 src/test/regress/expected/expressions.out |   2 +-
 src/test/regress/sql/expressions.sql      |   2 +-
 src/tools/pgindent/typedefs.list          |   2 -
 23 files changed, 245 insertions(+), 389 deletions(-)

diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index fd2559442e..35dc369728 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1520,6 +1520,21 @@
 { oid => '9977', descr => 'system user name',
   proname => 'system_user', provolatile => 's', prorettype => 'text',
   proargtypes => '', prosrc => 'system_user' },
+{ oid => '9978', descr => 'current date',
+  proname => 'current_date', provolatile => 's', prorettype => 'date',
+  proargtypes => '', prosrc => 'current_date' },
+{ oid => '9979', descr => 'current time',
+  proname => 'current_time', provolatile => 's', prorettype => 'timetz',
+  proargtypes => 'int4', prosrc => 'current_time', proisstrict => 'f' },
+{ oid => '9980', descr => 'current timestamp',
+  proname => 'current_timestamp', provolatile => 's', prorettype => 'timestamptz',
+  proargtypes => 'int4', prosrc => 'current_timestamp', proisstrict => 'f' },
+{ oid => '9981', descr => 'local time',
+  proname => 'localtime', provolatile => 's', prorettype => 'time',
+  proargtypes => 'int4', prosrc => 'sql_localtime', proisstrict => 'f' },
+{ oid => '9982', descr => 'local timestamp',
+  proname => 'localtimestamp', provolatile => 's', prorettype => 'timestamp',
+  proargtypes => 'int4', prosrc => 'sql_localtimestamp', proisstrict => 'f' },
 
 { oid => '744',
   proname => 'array_eq', prorettype => 'bool',
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index e14f15d435..0557302b92 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -170,7 +170,6 @@ typedef enum ExprEvalOp
 	EEOP_DISTINCT,
 	EEOP_NOT_DISTINCT,
 	EEOP_NULLIF,
-	EEOP_SQLVALUEFUNCTION,
 	EEOP_CURRENTOFEXPR,
 	EEOP_NEXTVALUEEXPR,
 	EEOP_ARRAYEXPR,
@@ -416,12 +415,6 @@ typedef struct ExprEvalStep
 			FunctionCallInfo fcinfo_data_in;
 		}			iocoerce;
 
-		/* for EEOP_SQLVALUEFUNCTION */
-		struct
-		{
-			SQLValueFunction *svf;
-		}			sqlvaluefunction;
-
 		/* for EEOP_NEXTVALUEEXPR */
 		struct
 		{
@@ -741,7 +734,6 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op,
 							  ExprContext *econtext);
 extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op,
 								ExprContext *econtext);
-extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalRowNull(ExprState *state, ExprEvalStep *op,
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index f6dd27edcc..74f228d959 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1292,39 +1292,6 @@ typedef struct MinMaxExpr
 	int			location;		/* token location, or -1 if unknown */
 } MinMaxExpr;
 
-/*
- * SQLValueFunction - parameterless functions with special grammar productions
- *
- * The SQL standard categorizes some of these as <datetime value function>
- * and others as <general value specification>.  We call 'em SQLValueFunctions
- * for lack of a better term.  We store type and typmod of the result so that
- * some code doesn't need to know each function individually, and because
- * we would need to store typmod anyway for some of the datetime functions.
- * Note that currently, all variants return non-collating datatypes, so we do
- * not need a collation field; also, all these functions are stable.
- */
-typedef enum SQLValueFunctionOp
-{
-	SVFOP_CURRENT_DATE,
-	SVFOP_CURRENT_TIME,
-	SVFOP_CURRENT_TIME_N,
-	SVFOP_CURRENT_TIMESTAMP,
-	SVFOP_CURRENT_TIMESTAMP_N,
-	SVFOP_LOCALTIME,
-	SVFOP_LOCALTIME_N,
-	SVFOP_LOCALTIMESTAMP,
-	SVFOP_LOCALTIMESTAMP_N
-} SQLValueFunctionOp;
-
-typedef struct SQLValueFunction
-{
-	Expr		xpr;
-	SQLValueFunctionOp op;		/* which function this is */
-	Oid			type;			/* result type/typmod */
-	int32		typmod;
-	int			location;		/* token location, or -1 if unknown */
-} SQLValueFunction;
-
 /*
  * XmlExpr - various SQL/XML functions requiring special grammar productions
  *
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index 0bbe889128..fad4878722 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -96,7 +96,6 @@ TimeTzADTPGetDatum(const TimeTzADT *X)
 
 
 /* date.c */
-extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
@@ -104,9 +103,6 @@ extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
 extern void EncodeSpecialDate(DateADT dt, char *str);
-extern DateADT GetSQLCurrentDate(void);
-extern TimeTzADT *GetSQLCurrentTime(int32 typmod);
-extern TimeADT GetSQLLocalTime(int32 typmod);
 extern int	time2tm(TimeADT time, struct pg_tm *tm, fsec_t *fsec);
 extern int	timetz2tm(TimeTzADT *time, struct pg_tm *tm, fsec_t *fsec, int *tzp);
 extern int	tm2time(struct pg_tm *tm, fsec_t fsec, TimeADT *result);
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 76b7b4a3ca..7fd0b58825 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -93,11 +93,7 @@ extern PGDLLIMPORT TimestampTz PgReloadTime;
 
 /* Internal routines (not fmgr-callable) */
 
-extern int32 anytimestamp_typmod_check(bool istz, int32 typmod);
-
 extern TimestampTz GetCurrentTimestamp(void);
-extern TimestampTz GetSQLCurrentTimestamp(int32 typmod);
-extern Timestamp GetSQLLocalTimestamp(int32 typmod);
 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 								long *secs, int *microsecs);
 extern long TimestampDifferenceMilliseconds(TimestampTz start_time,
diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 30a048f6b0..4c3b4c3f8e 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -594,6 +594,32 @@ LANGUAGE internal
 STRICT IMMUTABLE PARALLEL SAFE
 AS 'unicode_is_normalized';
 
+-- Functions with SQL-mandated special syntax and some defaults.
+CREATE OR REPLACE FUNCTION
+  "current_time"(int4 DEFAULT NULL)
+RETURNS timetz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_time';
+CREATE OR REPLACE FUNCTION
+  "current_timestamp"(int4 DEFAULT NULL)
+RETURNS timestamptz
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'current_timestamp';
+CREATE OR REPLACE FUNCTION
+  "localtime"(int4 DEFAULT NULL)
+RETURNS time
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtime';
+CREATE OR REPLACE FUNCTION
+  "localtimestamp"(int4 DEFAULT NULL)
+RETURNS timestamp
+LANGUAGE internal
+STABLE PARALLEL SAFE
+AS 'sql_localtimestamp';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 0ecb2f8610..81429b9f05 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -2210,17 +2210,6 @@ ExecInitExprRec(Expr *node, ExprState *state,
 				break;
 			}
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				scratch.opcode = EEOP_SQLVALUEFUNCTION;
-				scratch.d.sqlvaluefunction.svf = svf;
-
-				ExprEvalPushStep(state, &scratch);
-				break;
-			}
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 6ebf5c287e..1dab2787b7 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -452,7 +452,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 		&&CASE_EEOP_DISTINCT,
 		&&CASE_EEOP_NOT_DISTINCT,
 		&&CASE_EEOP_NULLIF,
-		&&CASE_EEOP_SQLVALUEFUNCTION,
 		&&CASE_EEOP_CURRENTOFEXPR,
 		&&CASE_EEOP_NEXTVALUEEXPR,
 		&&CASE_EEOP_ARRAYEXPR,
@@ -1301,17 +1300,6 @@ ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
 			EEO_NEXT();
 		}
 
-		EEO_CASE(EEOP_SQLVALUEFUNCTION)
-		{
-			/*
-			 * Doesn't seem worthwhile to have an inline implementation
-			 * efficiency-wise.
-			 */
-			ExecEvalSQLValueFunction(state, op);
-
-			EEO_NEXT();
-		}
-
 		EEO_CASE(EEOP_CURRENTOFEXPR)
 		{
 			/* error invocation uses space, and shouldn't ever occur */
@@ -2489,40 +2477,6 @@ ExecEvalParamExtern(ExprState *state, ExprEvalStep *op, ExprContext *econtext)
 			 errmsg("no value found for parameter %d", paramId)));
 }
 
-/*
- * Evaluate a SQLValueFunction expression.
- */
-void
-ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op)
-{
-	SQLValueFunction *svf = op->d.sqlvaluefunction.svf;
-
-	*op->resnull = false;
-
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			*op->resvalue = DateADTGetDatum(GetSQLCurrentDate());
-			break;
-		case SVFOP_CURRENT_TIME:
-		case SVFOP_CURRENT_TIME_N:
-			*op->resvalue = TimeTzADTPGetDatum(GetSQLCurrentTime(svf->typmod));
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			*op->resvalue = TimestampTzGetDatum(GetSQLCurrentTimestamp(svf->typmod));
-			break;
-		case SVFOP_LOCALTIME:
-		case SVFOP_LOCALTIME_N:
-			*op->resvalue = TimeADTGetDatum(GetSQLLocalTime(svf->typmod));
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-		case SVFOP_LOCALTIMESTAMP_N:
-			*op->resvalue = TimestampGetDatum(GetSQLLocalTimestamp(svf->typmod));
-			break;
-	}
-}
-
 /*
  * Raise error if a CURRENT OF expression is evaluated.
  *
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index 95d0807bdd..f114337f8e 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -1549,12 +1549,6 @@ llvm_compile_expr(ExprState *state)
 					break;
 				}
 
-			case EEOP_SQLVALUEFUNCTION:
-				build_EvalXFunc(b, mod, "ExecEvalSQLValueFunction",
-								v_state, op);
-				LLVMBuildBr(b, opblocks[opno + 1]);
-				break;
-
 			case EEOP_CURRENTOFEXPR:
 				build_EvalXFunc(b, mod, "ExecEvalCurrentOfExpr",
 								v_state, op);
diff --git a/src/backend/jit/llvm/llvmjit_types.c b/src/backend/jit/llvm/llvmjit_types.c
index 90ac6b83b5..5b416c5642 100644
--- a/src/backend/jit/llvm/llvmjit_types.c
+++ b/src/backend/jit/llvm/llvmjit_types.c
@@ -126,7 +126,6 @@ void	   *referenced_functions[] =
 	ExecEvalRow,
 	ExecEvalRowNotNull,
 	ExecEvalRowNull,
-	ExecEvalSQLValueFunction,
 	ExecEvalScalarArrayOp,
 	ExecEvalHashedScalarArrayOp,
 	ExecEvalSubPlan,
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 2585a3175c..af8620ceb7 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -210,9 +210,6 @@ exprType(const Node *expr)
 		case T_MinMaxExpr:
 			type = ((const MinMaxExpr *) expr)->minmaxtype;
 			break;
-		case T_SQLValueFunction:
-			type = ((const SQLValueFunction *) expr)->type;
-			break;
 		case T_XmlExpr:
 			if (((const XmlExpr *) expr)->op == IS_DOCUMENT)
 				type = BOOLOID;
@@ -474,8 +471,6 @@ exprTypmod(const Node *expr)
 				return typmod;
 			}
 			break;
-		case T_SQLValueFunction:
-			return ((const SQLValueFunction *) expr)->typmod;
 		case T_CoerceToDomain:
 			return ((const CoerceToDomain *) expr)->resulttypmod;
 		case T_CoerceToDomainValue:
@@ -916,10 +911,6 @@ exprCollation(const Node *expr)
 		case T_MinMaxExpr:
 			coll = ((const MinMaxExpr *) expr)->minmaxcollid;
 			break;
-		case T_SQLValueFunction:
-			/* Returns a non-collatable type */
-			coll = InvalidOid;
-			break;
 		case T_XmlExpr:
 
 			/*
@@ -1140,9 +1131,6 @@ exprSetCollation(Node *expr, Oid collation)
 		case T_MinMaxExpr:
 			((MinMaxExpr *) expr)->minmaxcollid = collation;
 			break;
-		case T_SQLValueFunction:
-			Assert(collation == InvalidOid);
-			break;
 		case T_XmlExpr:
 			Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ?
 				   (collation == DEFAULT_COLLATION_OID) :
@@ -1426,10 +1414,6 @@ exprLocation(const Node *expr)
 			/* GREATEST/LEAST keyword should always be the first thing */
 			loc = ((const MinMaxExpr *) expr)->location;
 			break;
-		case T_SQLValueFunction:
-			/* function keyword should always be the first thing */
-			loc = ((const SQLValueFunction *) expr)->location;
-			break;
 		case T_XmlExpr:
 			{
 				const XmlExpr *xexpr = (const XmlExpr *) expr;
@@ -1717,10 +1701,10 @@ set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
  * for themselves, in case additional checks should be made, or because they
  * have special rules about which parts of the tree need to be visited.
  *
- * Note: we ignore MinMaxExpr, SQLValueFunction, XmlExpr, CoerceToDomain,
- * and NextValueExpr nodes, because they do not contain SQL function OIDs.
- * However, they can invoke SQL-visible functions, so callers should take
- * thought about how to treat them.
+ * Note: we ignore MinMaxExpr, XmlExpr, CoerceToDomain, and NextValueExpr
+ * nodes, because they do not contain SQL function OIDs.  However, they can
+ * invoke SQL-visible functions, so callers should take thought about how
+ * to treat them.
  */
 bool
 check_functions_in_node(Node *node, check_function_callback checker,
@@ -1936,7 +1920,6 @@ expression_tree_walker_impl(Node *node,
 		case T_Const:
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -2673,7 +2656,6 @@ expression_tree_mutator_impl(Node *node,
 			break;
 		case T_Param:
 		case T_CaseTestExpr:
-		case T_SQLValueFunction:
 		case T_CoerceToDomainValue:
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
@@ -3587,7 +3569,6 @@ raw_expression_tree_walker_impl(Node *node,
 	{
 		case T_SetToDefault:
 		case T_CurrentOfExpr:
-		case T_SQLValueFunction:
 		case T_Integer:
 		case T_Float:
 		case T_Boolean:
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 4c6b1d1f55..897309d7ec 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -4603,7 +4603,6 @@ cost_qual_eval_walker(Node *node, cost_qual_eval_context *context)
 		}
 	}
 	else if (IsA(node, MinMaxExpr) ||
-			 IsA(node, SQLValueFunction) ||
 			 IsA(node, XmlExpr) ||
 			 IsA(node, CoerceToDomain) ||
 			 IsA(node, NextValueExpr))
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 33790a4f46..c61d9c68a0 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -383,12 +383,6 @@ contain_mutable_functions_walker(Node *node, void *context)
 								context))
 		return true;
 
-	if (IsA(node, SQLValueFunction))
-	{
-		/* all variants of SQLValueFunction are stable */
-		return true;
-	}
-
 	if (IsA(node, NextValueExpr))
 	{
 		/* NextValueExpr is volatile */
@@ -537,8 +531,8 @@ contain_volatile_functions_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.
 	 */
 
 	/* Recurse to check arguments */
@@ -583,10 +577,9 @@ contain_volatile_functions_not_nextval_walker(Node *node, void *context)
 
 	/*
 	 * See notes in contain_mutable_functions_walker about why we treat
-	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
-	 * SQLValueFunction is stable.  Hence, none of them are of interest here.
-	 * Also, since we're intentionally ignoring nextval(), presumably we
-	 * should ignore NextValueExpr.
+	 * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable.  Hence, none
+	 * of them are of interest here.  Also, since we're intentionally
+	 * ignoring nextval(), presumably we should ignore NextValueExpr.
 	 */
 
 	/* Recurse to check arguments */
@@ -732,8 +725,8 @@ max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
 	 * (Note: in principle that's wrong because a domain constraint could
 	 * contain a parallel-unsafe function; but useful constraints probably
 	 * never would have such, and assuming they do would cripple use of
-	 * parallel query in the presence of domain types.)  SQLValueFunction
-	 * should be safe in all cases.  NextValueExpr is parallel-unsafe.
+	 * parallel query in the presence of domain types.)  NextValueExpr is
+	 * parallel-unsafe.
 	 */
 	if (IsA(node, CoerceToDomain))
 	{
@@ -1180,7 +1173,6 @@ contain_leaked_vars_walker(Node *node, void *context)
 		case T_CaseExpr:
 		case T_CaseTestExpr:
 		case T_RowExpr:
-		case T_SQLValueFunction:
 		case T_NullTest:
 		case T_BooleanTest:
 		case T_NextValueExpr:
@@ -3194,23 +3186,6 @@ eval_const_expressions_mutator(Node *node,
 				newcoalesce->location = coalesceexpr->location;
 				return (Node *) newcoalesce;
 			}
-		case T_SQLValueFunction:
-			{
-				/*
-				 * All variants of SQLValueFunction are stable, so if we are
-				 * estimating the expression's value, we should evaluate the
-				 * current function value.  Otherwise just copy.
-				 */
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				if (context->estimate)
-					return (Node *) evaluate_expr((Expr *) svf,
-												  svf->type,
-												  svf->typmod,
-												  InvalidOid);
-				else
-					return copyObject((Node *) svf);
-			}
 		case T_FieldSelect:
 			{
 				/*
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 9054742427..9384214942 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -198,8 +198,6 @@ static Node *makeAndExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeOrExpr(Node *lexpr, Node *rexpr, int location);
 static Node *makeNotExpr(Node *expr, int location);
 static Node *makeAArrayExpr(List *elements, int location);
-static Node *makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod,
-								  int location);
 static Node *makeXmlExpr(XmlExprOp op, char *name, List *named_args,
 						 List *args, int location);
 static List *mergeTableFuncParameters(List *func_args, List *columns);
@@ -15195,39 +15193,66 @@ func_expr_common_subexpr:
 				}
 			| CURRENT_DATE
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_DATE, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_date"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_time"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_TIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_CURRENT_TIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("current_timestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIME '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIME_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtime"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP, -1, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   NIL,
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| LOCALTIMESTAMP '(' Iconst ')'
 				{
-					$$ = makeSQLValueFunction(SVFOP_LOCALTIMESTAMP_N, $3, @1);
+					$$ = (Node *) makeFuncCall(SystemFuncName("localtimestamp"),
+											   list_make1(makeIntConst($3, @3)),
+											   COERCE_SQL_SYNTAX,
+											   @1);
 				}
 			| CURRENT_ROLE
 				{
@@ -18166,18 +18191,6 @@ makeAArrayExpr(List *elements, int location)
 	return (Node *) n;
 }
 
-static Node *
-makeSQLValueFunction(SQLValueFunctionOp op, int32 typmod, int location)
-{
-	SQLValueFunction *svf = makeNode(SQLValueFunction);
-
-	svf->op = op;
-	/* svf->type will be filled during parse analysis */
-	svf->typmod = typmod;
-	svf->location = location;
-	return (Node *) svf;
-}
-
 static Node *
 makeXmlExpr(XmlExprOp op, char *name, List *named_args, List *args,
 			int location)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 0fdbf82f3a..150a8099c2 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -61,8 +61,6 @@ static Node *transformArrayExpr(ParseState *pstate, A_ArrayExpr *a,
 static Node *transformRowExpr(ParseState *pstate, RowExpr *r, bool allowDefault);
 static Node *transformCoalesceExpr(ParseState *pstate, CoalesceExpr *c);
 static Node *transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m);
-static Node *transformSQLValueFunction(ParseState *pstate,
-									   SQLValueFunction *svf);
 static Node *transformXmlExpr(ParseState *pstate, XmlExpr *x);
 static Node *transformXmlSerialize(ParseState *pstate, XmlSerialize *xs);
 static Node *transformBooleanTest(ParseState *pstate, BooleanTest *b);
@@ -240,11 +238,6 @@ transformExprRecurse(ParseState *pstate, Node *expr)
 			result = transformMinMaxExpr(pstate, (MinMaxExpr *) expr);
 			break;
 
-		case T_SQLValueFunction:
-			result = transformSQLValueFunction(pstate,
-											   (SQLValueFunction *) expr);
-			break;
-
 		case T_XmlExpr:
 			result = transformXmlExpr(pstate, (XmlExpr *) expr);
 			break;
@@ -2191,51 +2184,6 @@ transformMinMaxExpr(ParseState *pstate, MinMaxExpr *m)
 	return (Node *) newm;
 }
 
-static Node *
-transformSQLValueFunction(ParseState *pstate, SQLValueFunction *svf)
-{
-	/*
-	 * All we need to do is insert the correct result type and (where needed)
-	 * validate the typmod, so we just modify the node in-place.
-	 */
-	switch (svf->op)
-	{
-		case SVFOP_CURRENT_DATE:
-			svf->type = DATEOID;
-			break;
-		case SVFOP_CURRENT_TIME:
-			svf->type = TIMETZOID;
-			break;
-		case SVFOP_CURRENT_TIME_N:
-			svf->type = TIMETZOID;
-			svf->typmod = anytime_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_CURRENT_TIMESTAMP:
-			svf->type = TIMESTAMPTZOID;
-			break;
-		case SVFOP_CURRENT_TIMESTAMP_N:
-			svf->type = TIMESTAMPTZOID;
-			svf->typmod = anytimestamp_typmod_check(true, svf->typmod);
-			break;
-		case SVFOP_LOCALTIME:
-			svf->type = TIMEOID;
-			break;
-		case SVFOP_LOCALTIME_N:
-			svf->type = TIMEOID;
-			svf->typmod = anytime_typmod_check(false, svf->typmod);
-			break;
-		case SVFOP_LOCALTIMESTAMP:
-			svf->type = TIMESTAMPOID;
-			break;
-		case SVFOP_LOCALTIMESTAMP_N:
-			svf->type = TIMESTAMPOID;
-			svf->typmod = anytimestamp_typmod_check(false, svf->typmod);
-			break;
-	}
-
-	return (Node *) svf;
-}
-
 static Node *
 transformXmlExpr(ParseState *pstate, XmlExpr *x)
 {
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index f54591a987..8e0d6fd01f 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1872,31 +1872,6 @@ FigureColnameInternal(Node *node, char **name)
 					return 2;
 			}
 			break;
-		case T_SQLValueFunction:
-			/* make these act like a function or variable */
-			switch (((SQLValueFunction *) node)->op)
-			{
-				case SVFOP_CURRENT_DATE:
-					*name = "current_date";
-					return 2;
-				case SVFOP_CURRENT_TIME:
-				case SVFOP_CURRENT_TIME_N:
-					*name = "current_time";
-					return 2;
-				case SVFOP_CURRENT_TIMESTAMP:
-				case SVFOP_CURRENT_TIMESTAMP_N:
-					*name = "current_timestamp";
-					return 2;
-				case SVFOP_LOCALTIME:
-				case SVFOP_LOCALTIME_N:
-					*name = "localtime";
-					return 2;
-				case SVFOP_LOCALTIMESTAMP:
-				case SVFOP_LOCALTIMESTAMP_N:
-					*name = "localtimestamp";
-					return 2;
-			}
-			break;
 		case T_XmlExpr:
 			/* make SQL/XML functions act like a regular function */
 			switch (((XmlExpr *) node)->op)
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index a2bdde0459..10c11e00db 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -46,27 +46,6 @@
 
 /* common code for timetypmodin and timetztypmodin */
 static int32
-anytime_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIME
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytime_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytime_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -87,6 +66,26 @@ anytime_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytime_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIME
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytime_typmod_check(istz, tl[0]);
+}
+
 /* common code for timetypmodout and timetztypmodout */
 static char *
 anytime_typmodout(bool istz, int32 typmod)
@@ -296,10 +295,10 @@ EncodeSpecialDate(DateADT dt, char *str)
 
 
 /*
- * GetSQLCurrentDate -- implements CURRENT_DATE
+ * current_date -- implements CURRENT_DATE
  */
-DateADT
-GetSQLCurrentDate(void)
+Datum
+current_date(PG_FUNCTION_ARGS)
 {
 	struct pg_tm tm;
 
@@ -325,46 +324,62 @@ GetSQLCurrentDate(void)
 		cache_mday = tm.tm_mday;
 	}
 
-	return cache_date;
+	return DateADTGetDatum(cache_date);
 }
 
 /*
- * GetSQLCurrentTime -- implements CURRENT_TIME, CURRENT_TIME(n)
+ * current_time -- implements CURRENT_TIME, CURRENT_TIME(n)
  */
-TimeTzADT *
-GetSQLCurrentTime(int32 typmod)
+Datum
+current_time(PG_FUNCTION_ARGS)
 {
 	TimeTzADT  *result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(true, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	result = (TimeTzADT *) palloc(sizeof(TimeTzADT));
 	tm2timetz(tm, fsec, tz, result);
 	AdjustTimeForTypmod(&(result->time), typmod);
-	return result;
+
+	return TimeTzADTPGetDatum(result);
 }
 
 /*
- * GetSQLLocalTime -- implements LOCALTIME, LOCALTIME(n)
+ * sql_localtime -- implements LOCALTIME, LOCALTIME(n)
  */
-TimeADT
-GetSQLLocalTime(int32 typmod)
+Datum
+sql_localtime(PG_FUNCTION_ARGS)
 {
 	TimeADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytime_typmod_check(false, typmod);
+	}
 
 	GetCurrentTimeUsec(tm, &fsec, &tz);
 
 	tm2time(tm, fsec, &result);
 	AdjustTimeForTypmod(&result, typmod);
-	return result;
+
+	return TimeADTGetDatum(result);
 }
 
 
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 129f3333fb..c00dc5e32e 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8150,7 +8150,6 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
 		case T_RowExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 		case T_NextValueExpr:
 		case T_NullIfExpr:
@@ -9130,49 +9129,6 @@ get_rule_expr(Node *node, deparse_context *context,
 			}
 			break;
 
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				/*
-				 * Note: this code knows that typmod for time, timestamp, and
-				 * timestamptz just prints as integer.
-				 */
-				switch (svf->op)
-				{
-					case SVFOP_CURRENT_DATE:
-						appendStringInfoString(buf, "CURRENT_DATE");
-						break;
-					case SVFOP_CURRENT_TIME:
-						appendStringInfoString(buf, "CURRENT_TIME");
-						break;
-					case SVFOP_CURRENT_TIME_N:
-						appendStringInfo(buf, "CURRENT_TIME(%d)", svf->typmod);
-						break;
-					case SVFOP_CURRENT_TIMESTAMP:
-						appendStringInfoString(buf, "CURRENT_TIMESTAMP");
-						break;
-					case SVFOP_CURRENT_TIMESTAMP_N:
-						appendStringInfo(buf, "CURRENT_TIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-					case SVFOP_LOCALTIME:
-						appendStringInfoString(buf, "LOCALTIME");
-						break;
-					case SVFOP_LOCALTIME_N:
-						appendStringInfo(buf, "LOCALTIME(%d)", svf->typmod);
-						break;
-					case SVFOP_LOCALTIMESTAMP:
-						appendStringInfoString(buf, "LOCALTIMESTAMP");
-						break;
-					case SVFOP_LOCALTIMESTAMP_N:
-						appendStringInfo(buf, "LOCALTIMESTAMP(%d)",
-										 svf->typmod);
-						break;
-				}
-			}
-			break;
-
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
@@ -9698,7 +9654,6 @@ looks_like_function(Node *node)
 		case T_NullIfExpr:
 		case T_CoalesceExpr:
 		case T_MinMaxExpr:
-		case T_SQLValueFunction:
 		case T_XmlExpr:
 			/* these are all accepted by func_expr_common_subexpr */
 			return true;
@@ -10292,6 +10247,70 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			appendStringInfoString(buf, "SYSTEM_USER");
 			return true;
 
+		case F_CURRENT_DATE:
+			appendStringInfoString(buf, "CURRENT_DATE");
+			return true;
+		case F_CURRENT_TIME:
+			appendStringInfoString(buf, "CURRENT_TIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_CURRENT_TIMESTAMP:
+			appendStringInfoString(buf, "CURRENT_TIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIME:
+			appendStringInfoString(buf, "LOCALTIME");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+		case F_LOCALTIMESTAMP:
+			appendStringInfoString(buf, "LOCALTIMESTAMP");
+			if (list_length(expr->args) == 1)
+			{
+				Const      *cons = (Const *) linitial(expr->args);
+
+				Assert(IsA(cons, Const));
+				if (!cons->constisnull)
+				{
+					appendStringInfoString(buf, "(");
+					get_rule_expr((Node *) cons, context, false);
+					appendStringInfoString(buf, ")");
+				}
+			}
+			return true;
+
 		case F_XMLEXISTS:
 			/* XMLEXISTS ... extra parens because args are c_expr */
 			appendStringInfoString(buf, "XMLEXISTS((");
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index d8552a1f18..ef92323fd0 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -81,27 +81,6 @@ static Timestamp timestamptz2timestamp(TimestampTz timestamp);
 
 /* common code for timestamptypmodin and timestamptztypmodin */
 static int32
-anytimestamp_typmodin(bool istz, ArrayType *ta)
-{
-	int32	   *tl;
-	int			n;
-
-	tl = ArrayGetIntegerTypmods(ta, &n);
-
-	/*
-	 * we're not too tense about good error message here because grammar
-	 * shouldn't allow wrong number of modifiers for TIMESTAMP
-	 */
-	if (n != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid type modifier")));
-
-	return anytimestamp_typmod_check(istz, tl[0]);
-}
-
-/* exported so parse_expr.c can use it */
-int32
 anytimestamp_typmod_check(bool istz, int32 typmod)
 {
 	if (typmod < 0)
@@ -122,6 +101,26 @@ anytimestamp_typmod_check(bool istz, int32 typmod)
 	return typmod;
 }
 
+static int32
+anytimestamp_typmodin(bool istz, ArrayType *ta)
+{
+	int32	   *tl;
+	int			n;
+
+	tl = ArrayGetIntegerTypmods(ta, &n);
+
+	/*
+	 * we're not too tense about good error message here because grammar
+	 * shouldn't allow wrong number of modifiers for TIMESTAMP
+	 */
+	if (n != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("invalid type modifier")));
+
+	return anytimestamp_typmod_check(istz, tl[0]);
+}
+
 /* common code for timestamptypmodout and timestamptztypmodout */
 static char *
 anytimestamp_typmodout(bool istz, int32 typmod)
@@ -1586,33 +1585,48 @@ GetCurrentTimestamp(void)
 }
 
 /*
- * GetSQLCurrentTimestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
+ * current_timestamp -- implements CURRENT_TIMESTAMP, CURRENT_TIMESTAMP(n)
  */
-TimestampTz
-GetSQLCurrentTimestamp(int32 typmod)
+Datum
+current_timestamp(PG_FUNCTION_ARGS)
 {
 	TimestampTz ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(true, typmod);
+	}
 
 	ts = GetCurrentTransactionStartTimestamp();
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampTzGetDatum(ts);
 }
 
 /*
- * GetSQLLocalTimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
+ * sql_localtimestamp -- implements LOCALTIMESTAMP, LOCALTIMESTAMP(n)
  */
-Timestamp
-GetSQLLocalTimestamp(int32 typmod)
+Datum
+sql_localtimestamp(PG_FUNCTION_ARGS)
 {
 	Timestamp	ts;
+	int32		typmod = -1;
+
+	if (!PG_ARGISNULL(0))
+	{
+		typmod = PG_GETARG_INT32(0);
+		anytimestamp_typmod_check(false, typmod);
+	}
 
 	ts = timestamptz2timestamp(GetCurrentTransactionStartTimestamp());
 	if (typmod >= 0)
 		AdjustTimestampForTypmod(&ts, typmod);
-	return ts;
+	return TimestampGetDatum(ts);
 }
 
+
 /*
  * timeofday(*) -- returns the current time as a text.
  */
diff --git a/src/backend/utils/misc/queryjumble.c b/src/backend/utils/misc/queryjumble.c
index a8508463e7..0ace74de78 100644
--- a/src/backend/utils/misc/queryjumble.c
+++ b/src/backend/utils/misc/queryjumble.c
@@ -606,15 +606,6 @@ JumbleExpr(JumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) mmexpr->args);
 			}
 			break;
-		case T_SQLValueFunction:
-			{
-				SQLValueFunction *svf = (SQLValueFunction *) node;
-
-				APP_JUMB(svf->op);
-				/* type is fully determined by op */
-				APP_JUMB(svf->typmod);
-			}
-			break;
 		case T_XmlExpr:
 			{
 				XmlExpr    *xexpr = (XmlExpr *) node;
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 5bf39fd9aa..28a20900f1 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -2,7 +2,7 @@
 -- expression evaluation tests that don't fit into a more specific file
 --
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 -- current_date  (always matches because of transactional behaviour)
 SELECT date(now())::text = current_date::text;
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index 0e163cc0d7..f9a0299d17 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -3,7 +3,7 @@
 --
 
 --
--- Tests for SQLValueFunction
+-- Tests for various FuncCalls with COERCE_SQL_SYNTAX.
 --
 
 
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index f8302f1ed1..2f5802195d 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2397,8 +2397,6 @@ SQLFunctionCache
 SQLFunctionCachePtr
 SQLFunctionParseInfo
 SQLFunctionParseInfoPtr
-SQLValueFunction
-SQLValueFunctionOp
 SSL
 SSLExtensionInfoContext
 SSL_CTX
-- 
2.38.1

From 5ec10492cda8930c014f8db315650cffa7ea57e1 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Mon, 21 Nov 2022 08:08:44 +0900
Subject: [PATCH v5 2/2] Simplify back-parsing of SQL-callable timestamp
 functions

Per suggestion from Ted Yu.
---
 src/backend/utils/adt/ruleutils.c | 79 ++++++++++++-------------------
 1 file changed, 31 insertions(+), 48 deletions(-)

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index c00dc5e32e..ab926bedd4 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -9997,6 +9997,33 @@ get_windowfunc_expr(WindowFunc *wfunc, deparse_context *context)
 	}
 }
 
+/*
+ * get_func_sql_syntax_time
+ *
+ * Parse back argument of SQL-syntax function call related to a time or a
+ * timestamp.  These require a specific handling with their typmod is given
+ * by the function caller through their SQL keyword.
+ */
+static void
+get_func_sql_syntax_time(List *args, deparse_context *context)
+{
+	StringInfo	buf = context->buf;
+	Const      *cons;
+
+	if (list_length(args) != 1)
+		return;
+
+	cons = (Const *) linitial(args);
+	Assert(IsA(cons, Const));
+
+	if (!cons->constisnull)
+	{
+		appendStringInfoString(buf, "(");
+		get_rule_expr((Node *) cons, context, false);
+		appendStringInfoString(buf, ")");
+	}
+}
+
 /*
  * get_func_sql_syntax		- Parse back a SQL-syntax function call
  *
@@ -10252,63 +10279,19 @@ get_func_sql_syntax(FuncExpr *expr, deparse_context *context)
 			return true;
 		case F_CURRENT_TIME:
 			appendStringInfoString(buf, "CURRENT_TIME");
-			if (list_length(expr->args) == 1)
-			{
-				Const      *cons = (Const *) linitial(expr->args);
-
-				Assert(IsA(cons, Const));
-				if (!cons->constisnull)
-				{
-					appendStringInfoString(buf, "(");
-					get_rule_expr((Node *) cons, context, false);
-					appendStringInfoString(buf, ")");
-				}
-			}
+			get_func_sql_syntax_time(expr->args, context);
 			return true;
 		case F_CURRENT_TIMESTAMP:
 			appendStringInfoString(buf, "CURRENT_TIMESTAMP");
-			if (list_length(expr->args) == 1)
-			{
-				Const      *cons = (Const *) linitial(expr->args);
-
-				Assert(IsA(cons, Const));
-				if (!cons->constisnull)
-				{
-					appendStringInfoString(buf, "(");
-					get_rule_expr((Node *) cons, context, false);
-					appendStringInfoString(buf, ")");
-				}
-			}
+			get_func_sql_syntax_time(expr->args, context);
 			return true;
 		case F_LOCALTIME:
 			appendStringInfoString(buf, "LOCALTIME");
-			if (list_length(expr->args) == 1)
-			{
-				Const      *cons = (Const *) linitial(expr->args);
-
-				Assert(IsA(cons, Const));
-				if (!cons->constisnull)
-				{
-					appendStringInfoString(buf, "(");
-					get_rule_expr((Node *) cons, context, false);
-					appendStringInfoString(buf, ")");
-				}
-			}
+			get_func_sql_syntax_time(expr->args, context);
 			return true;
 		case F_LOCALTIMESTAMP:
 			appendStringInfoString(buf, "LOCALTIMESTAMP");
-			if (list_length(expr->args) == 1)
-			{
-				Const      *cons = (Const *) linitial(expr->args);
-
-				Assert(IsA(cons, Const));
-				if (!cons->constisnull)
-				{
-					appendStringInfoString(buf, "(");
-					get_rule_expr((Node *) cons, context, false);
-					appendStringInfoString(buf, ")");
-				}
-			}
+			get_func_sql_syntax_time(expr->args, context);
 			return true;
 
 		case F_XMLEXISTS:
-- 
2.38.1

From b599765b222aacbc860ba43c42ec658ed1a8b989 Mon Sep 17 00:00:00 2001
From: Ian Barwick <barwick@gmail.com>
Date: Fri, 30 Dec 2022 10:48:31 +0900
Subject: [PATCH v1] Fix [current_|local]timestamp precision reduction

Fixes regression introduced in f193883f.
---
 src/backend/utils/adt/timestamp.c         | 10 ++--------
 src/test/regress/expected/expressions.out | 15 +++++++++++++++
 src/test/regress/sql/expressions.sql      |  3 +++
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 3f2508c0c4..b23cce1136 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -1606,10 +1606,7 @@ current_timestamp(PG_FUNCTION_ARGS)
 	int32		typmod = -1;
 
 	if (!PG_ARGISNULL(0))
-	{
-		typmod = PG_GETARG_INT32(0);
-		anytimestamp_typmod_check(true, typmod);
-	}
+		typmod = anytimestamp_typmod_check(true, PG_GETARG_INT32(0));
 
 	ts = GetCurrentTransactionStartTimestamp();
 	if (typmod >= 0)
@@ -1627,10 +1624,7 @@ sql_localtimestamp(PG_FUNCTION_ARGS)
 	int32		typmod = -1;
 
 	if (!PG_ARGISNULL(0))
-	{
-		typmod = PG_GETARG_INT32(0);
-		anytimestamp_typmod_check(false, typmod);
-	}
+		typmod = anytimestamp_typmod_check(false, PG_GETARG_INT32(0));
 
 	ts = timestamptz2timestamp(GetCurrentTransactionStartTimestamp());
 	if (typmod >= 0)
diff --git a/src/test/regress/expected/expressions.out b/src/test/regress/expected/expressions.out
index 28a20900f1..fd38830a77 100644
--- a/src/test/regress/expected/expressions.out
+++ b/src/test/regress/expected/expressions.out
@@ -50,6 +50,14 @@ SELECT length(current_timestamp::text) >= length(current_timestamp(0)::text);
  t
 (1 row)
 
+-- precision overflow
+SELECT current_timestamp = current_timestamp(7);
+WARNING:  TIMESTAMP(7) WITH TIME ZONE precision reduced to maximum allowed, 6
+ ?column? 
+----------
+ t
+(1 row)
+
 -- localtimestamp
 SELECT now()::timestamp::text = localtimestamp::text;
  ?column? 
@@ -57,6 +65,13 @@ SELECT now()::timestamp::text = localtimestamp::text;
  t
 (1 row)
 
+SELECT localtimestamp = localtimestamp(7);
+WARNING:  TIMESTAMP(7) precision reduced to maximum allowed, 6
+ ?column? 
+----------
+ t
+(1 row)
+
 -- current_role/user/user is tested in rolnames.sql
 -- current database / catalog
 SELECT current_catalog = current_database();
diff --git a/src/test/regress/sql/expressions.sql b/src/test/regress/sql/expressions.sql
index f9a0299d17..57dfb37745 100644
--- a/src/test/regress/sql/expressions.sql
+++ b/src/test/regress/sql/expressions.sql
@@ -21,8 +21,11 @@ SELECT now()::time(3)::text = localtime(3)::text;
 SELECT current_timestamp = NOW();
 -- precision
 SELECT length(current_timestamp::text) >= length(current_timestamp(0)::text);
+-- precision overflow
+SELECT current_timestamp = current_timestamp(7);
 -- localtimestamp
 SELECT now()::timestamp::text = localtimestamp::text;
+SELECT localtimestamp = localtimestamp(7);
 
 -- current_role/user/user is tested in rolnames.sql
 

base-commit: 388e80132c007a7528abc987e347e41432dc1542
-- 
2.31.1