From: Andres Freund <andres@anarazel.de>
Date: Wed, 13 Dec 2017 23:34:20 +0000 (-0800)
Subject: Add pg_attribute_always_inline.
X-Git-Tag: REL_11_BETA1~1072
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=dbb3d6f0102e0aca7575ff864450fca57ac85517;p=postgresql

Add pg_attribute_always_inline.

Sometimes it is useful to be able to insist that the compiler inline a
function that its normal cost analysis would not normally choose to inline.
This can be useful for instantiating different variants of a function that
remove branches of code by constant folding.

Author: Thomas Munro
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CAEepm=09rr65VN+cAV5FgyM_z=D77Xy8Fuc9CDDDYbq3pQUezg@mail.gmail.com
---

diff --git a/src/include/c.h b/src/include/c.h
index a61428843a..11fcffbae3 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -146,6 +146,16 @@
 #define pg_attribute_noreturn()
 #endif
 
+/* GCC, Sunpro and XLC support always_inline via __attribute__ */
+#if defined(__GNUC__)
+#define pg_attribute_always_inline __attribute__((always_inline))
+/* msvc via a special keyword */
+#elif defined(_MSC_VER)
+#define pg_attribute_always_inline __forceinline
+#else
+#define pg_attribute_always_inline
+#endif
+
 /*
  * Forcing a function not to be inlined can be useful if it's the slow path of
  * a performance-critical function, or should be visible in profiles to allow