mirror of https://gitee.com/openkylin/wget.git
50 lines
1.5 KiB
Plaintext
50 lines
1.5 KiB
Plaintext
dnl Check for __builtin_expect.
|
|
|
|
dnl Copyright 2016-2023 Free Software Foundation, Inc.
|
|
dnl This file is free software; the Free Software Foundation
|
|
dnl gives unlimited permission to copy and/or distribute it,
|
|
dnl with or without modifications, as long as this notice is preserved.
|
|
|
|
dnl Written by Paul Eggert.
|
|
|
|
AC_DEFUN([gl___BUILTIN_EXPECT],
|
|
[
|
|
AC_CACHE_CHECK([for __builtin_expect],
|
|
[gl_cv___builtin_expect],
|
|
[AC_LINK_IFELSE(
|
|
[AC_LANG_SOURCE([[
|
|
int
|
|
main (int argc, char **argv)
|
|
{
|
|
argc = __builtin_expect (argc, 100);
|
|
return argv[argc != 100][0];
|
|
}]])],
|
|
[gl_cv___builtin_expect=yes],
|
|
[AC_LINK_IFELSE(
|
|
[AC_LANG_SOURCE([[
|
|
#include <builtins.h>
|
|
int
|
|
main (int argc, char **argv)
|
|
{
|
|
argc = __builtin_expect (argc, 100);
|
|
return argv[argc != 100][0];
|
|
}]])],
|
|
[gl_cv___builtin_expect="in <builtins.h>"],
|
|
[gl_cv___builtin_expect=no])])])
|
|
if test "$gl_cv___builtin_expect" = yes; then
|
|
AC_DEFINE([HAVE___BUILTIN_EXPECT], [1])
|
|
elif test "$gl_cv___builtin_expect" = "in <builtins.h>"; then
|
|
AC_DEFINE([HAVE___BUILTIN_EXPECT], [2])
|
|
fi
|
|
AH_VERBATIM([HAVE___BUILTIN_EXPECT],
|
|
[/* Define to 1 if the compiler supports __builtin_expect,
|
|
and to 2 if <builtins.h> does. */
|
|
#undef HAVE___BUILTIN_EXPECT
|
|
#ifndef HAVE___BUILTIN_EXPECT
|
|
# define __builtin_expect(e, c) (e)
|
|
#elif HAVE___BUILTIN_EXPECT == 2
|
|
# include <builtins.h>
|
|
#endif
|
|
])
|
|
])
|