X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Fcompiler.h;h=2715d91b6a921b598a043d56b289c3fe1f89299f;hb=545c6af1daceb29e4a9dc419273a3f2339dfaa7c;hp=3d92f2fac5f1e05eef2a93f4191e1dd489465df7;hpb=048bd6f9e7f316aafede310ba273776d0086b8ed;p=coloredstderr%2Fcoloredstderr.git

diff --git a/src/compiler.h b/src/compiler.h
index 3d92f2f..2715d91 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -1,7 +1,7 @@
 /*
  * Compiler specific macros.
  *
- * Copyright (C) 2013  Simon Ruderich
+ * Copyright (C) 2013-2018  Simon Ruderich
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,6 +20,27 @@
 #ifndef COMPILER_H
 #define COMPILER_H 1
 
+#ifdef HAVE___ATTRIBUTE__
+/* Prevent/force inlining. Used to improve performance. */
+# define noinline      __attribute__((noinline))
+# define always_inline __attribute__((always_inline))
+/* Unused parameter. */
+# define unused        __attribute__((unused))
+/* Mark the function protected, which means it can't be overwritten by other
+ * modules (libraries), e.g. with LD_PRELOAD); otherwise same as the default
+ * visibility. This causes the compiler not use the PLT (and no relocations)
+ * for local calls from inside this module; but the symbols are still
+ * exported. This is faster and in this case prevents useless lookups as we
+ * hook those functions and nobody else should modify them. Not strictly
+ * necessary, but nice to have. */
+# define visibility_protected __attribute__((visibility("protected")))
+#else
+# define noinline
+# define always_inline
+# define unused
+# define visibility_protected
+#endif
+
 /* Branch prediction information for the compiler. */
 #ifdef HAVE___BUILTIN_EXPECT
 # define likely(x)   __builtin_expect(!!(x), 1)