From bb7fe17a98b0fbe8980e2b67787b4918ad81b560 Mon Sep 17 00:00:00 2001
From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Wed, 12 Mar 2025 10:44:46 +0300
Subject: [PATCH v11 6/7] meson: Add LLVM bitcode emission for backend sources

Since generated backend sources may have their own compilation flags and
must also be included in the postgres.index.bc, the way to make it work
with current code was to create a new variable, called
`bc_generated_backend_sources`, which is a list of dictionaries, each
one having an optional 'additional_flags' and a `srclist` pointing to
the list of custom_target generated sources.

An example of a possible structure of bitcode_modules which is processed
by the main meson llvm bitcode emission file
src/backend/jit/llvm/bitcode/meson.build:
```
bitcode_modules = [
  {
    'name': 'postgres',
    'target': postgres_lib,
    'src_file': backend_sources,
    'gen_srcfiles': [
      {
        'additional_flags': [
          '-I/path/postgresl/src/backend/parser',
          '-I/path/postgresl/build/src/backend/parser',
        ],
        'srcfiles': [
                <custom_target for scan.c>,
                <custom_target for gram.c>
        ]
      }
    ]
  }
]
```

Author: Diego Fronza <diego.fronza@percona.com>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/206b001d-1884-4081-bd02-bed5c92f02ba%40eisentraut.org
---
 src/backend/bootstrap/meson.build   | 2 ++
 src/backend/meson.build             | 2 ++
 src/backend/parser/meson.build      | 8 ++++++++
 src/backend/replication/meson.build | 4 ++++
 src/backend/utils/fmgr/meson.build  | 1 +
 5 files changed, 17 insertions(+)

diff --git a/src/backend/bootstrap/meson.build b/src/backend/bootstrap/meson.build
index 2f9115fc97c..f49e27f3889 100644
--- a/src/backend/bootstrap/meson.build
+++ b/src/backend/bootstrap/meson.build
@@ -13,6 +13,7 @@ bootscanner = custom_target('bootscanner',
 )
 generated_sources += bootscanner
 boot_parser_sources += bootscanner
+bc_generated_backend_sources += {'srcfiles': [bootscanner]}
 
 bootparse = custom_target('bootparse',
   input: 'bootparse.y',
@@ -20,6 +21,7 @@ bootparse = custom_target('bootparse',
 )
 generated_sources += bootparse.to_list()
 boot_parser_sources += bootparse
+bc_generated_backend_sources += {'srcfiles': [bootparse[0]]}
 
 boot_parser = static_library('boot_parser',
   boot_parser_sources,
diff --git a/src/backend/meson.build b/src/backend/meson.build
index 2877127954b..102006ccd35 100644
--- a/src/backend/meson.build
+++ b/src/backend/meson.build
@@ -5,6 +5,7 @@ backend_sources = []
 backend_link_with = [pgport_srv, common_srv]
 
 generated_backend_sources = []
+bc_generated_backend_sources = []
 post_export_backend_sources = []
 
 var_bitcode_cflags = []
@@ -172,6 +173,7 @@ bitcode_modules += {
   'name': 'postgres',
   'target': postgres_lib,
   'srcfiles': backend_sources,
+  'gen_sources': bc_generated_backend_sources,
 }
 
 pg_mod_c_args = cflags_mod
diff --git a/src/backend/parser/meson.build b/src/backend/parser/meson.build
index 86c09b29ec2..a8d65eb1898 100644
--- a/src/backend/parser/meson.build
+++ b/src/backend/parser/meson.build
@@ -43,6 +43,14 @@ backend_parser = custom_target('gram',
 generated_sources += backend_parser.to_list()
 parser_sources += backend_parser
 
+bc_generated_backend_sources += {
+  'additional_flags': [
+    '-I@0@'.format(meson.current_build_dir()),
+    '-I@0@'.format(meson.current_source_dir()),
+  ],
+  'srcfiles': [backend_scanner, backend_parser[0]],
+}
+
 parser = static_library('parser',
   parser_sources,
   dependencies: [backend_code],
diff --git a/src/backend/replication/meson.build b/src/backend/replication/meson.build
index ce9be4117ad..a4789f1f86f 100644
--- a/src/backend/replication/meson.build
+++ b/src/backend/replication/meson.build
@@ -19,6 +19,7 @@ repl_scanner = custom_target('repl_scanner',
 )
 generated_sources += repl_scanner
 repl_parser_sources += repl_scanner
+bc_generated_backend_sources += {'srcfiles': [repl_scanner]}
 
 repl_gram = custom_target('repl_gram',
   input: 'repl_gram.y',
@@ -26,6 +27,7 @@ repl_gram = custom_target('repl_gram',
 )
 generated_sources += repl_gram.to_list()
 repl_parser_sources += repl_gram
+bc_generated_backend_sources += {'srcfiles': [repl_gram[0]]}
 
 syncrep_scanner = custom_target('syncrep_scanner',
   input: 'syncrep_scanner.l',
@@ -34,6 +36,7 @@ syncrep_scanner = custom_target('syncrep_scanner',
 )
 generated_sources += syncrep_scanner
 repl_parser_sources += syncrep_scanner
+bc_generated_backend_sources += {'srcfiles': [syncrep_scanner]}
 
 syncrep_gram = custom_target('syncrep_gram',
   input: 'syncrep_gram.y',
@@ -41,6 +44,7 @@ syncrep_gram = custom_target('syncrep_gram',
 )
 generated_sources += syncrep_gram.to_list()
 repl_parser_sources += syncrep_gram
+bc_generated_backend_sources += {'srcfiles': [syncrep_gram[0]]}
 
 repl_parser = static_library('repl_parser',
   repl_parser_sources,
diff --git a/src/backend/utils/fmgr/meson.build b/src/backend/utils/fmgr/meson.build
index 3a90deba979..71dad370d1d 100644
--- a/src/backend/utils/fmgr/meson.build
+++ b/src/backend/utils/fmgr/meson.build
@@ -8,3 +8,4 @@ backend_sources += files(
 
 # fmgrtab.c
 generated_backend_sources += fmgrtab_target[2]
+bc_generated_backend_sources += {'srcfiles': [fmgrtab_target[2]]}
-- 
2.47.3