From 0c242cfd6e09d377f75febec0adaa705ff27c7f0 Mon Sep 17 00:00:00 2001
From: David Fetter <david@fetter.org>
Date: Sat, 11 Jan 2020 17:38:12 -0800
Subject: [PATCH v1] Make pq_begintypsend more efficient
To: hackers
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by replacing 4 calls to appendStringInfoCharMacro with one call to
appendStringInfoSpaces.

In passing, make appendStringInfoSpaces more efficient by turning a
while() loop into a memset() + increment.

diff --git a/src/backend/libpq/pqformat.c b/src/backend/libpq/pqformat.c
index a6f990c2d2..a4c6cdab80 100644
--- a/src/backend/libpq/pqformat.c
+++ b/src/backend/libpq/pqformat.c
@@ -329,10 +329,7 @@ pq_begintypsend(StringInfo buf)
 {
 	initStringInfo(buf);
 	/* Reserve four bytes for the bytea length word */
-	appendStringInfoCharMacro(buf, '\0');
-	appendStringInfoCharMacro(buf, '\0');
-	appendStringInfoCharMacro(buf, '\0');
-	appendStringInfoCharMacro(buf, '\0');
+	appendStringInfoSpaces(buf, 4);
 }
 
 /* --------------------------------
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index 0badc46554..87074af476 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -211,8 +211,8 @@ appendStringInfoSpaces(StringInfo str, int count)
 		enlargeStringInfo(str, count);
 
 		/* OK, append the spaces */
-		while (--count >= 0)
-			str->data[str->len++] = ' ';
+		memset(&str->data[str->len], ' ', count);
+		str->len += count;
 		str->data[str->len] = '\0';
 	}
 }

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