diff options
| author | Borislav Petkov <bp@suse.de> | 2013-06-28 20:41:41 +0400 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2013-06-29 02:26:48 +0400 |
| commit | 62122fd7dadac09704782d8bc051fb898a0272bd (patch) | |
| tree | 587c059270c340289a3789edc4a2fc6a2a1100c8 /arch/x86/include/asm/cpufeature.h | |
| parent | 9f84b6267ccde1bebe3f9cd40a91716b5ece5e20 (diff) | |
| download | linux-62122fd7dadac09704782d8bc051fb898a0272bd.tar.xz | |
x86, cpufeature: Use new CC_HAVE_ASM_GOTO
... for checking for "asm goto" compiler support. It is more explicit
this way and we cover the cases where distros have backported that
support even to gcc versions < 4.5.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1372437701-13351-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/include/asm/cpufeature.h')
| -rw-r--r-- | arch/x86/include/asm/cpufeature.h | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 47538a61c91b..d3f5c63078d8 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -366,9 +366,10 @@ extern bool __static_cpu_has_safe(u16 bit); */ static __always_inline __pure bool __static_cpu_has(u16 bit) { -#if __GNUC__ > 4 || __GNUC_MINOR__ >= 5 +#ifdef CC_HAVE_ASM_GOTO #ifdef CONFIG_X86_DEBUG_STATIC_CPU_HAS + /* * Catch too early usage of this before alternatives * have run. @@ -384,6 +385,7 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) ".previous\n" /* skipping size check since replacement size = 0 */ : : "i" (X86_FEATURE_ALWAYS) : : t_warn); + #endif asm goto("1: jmp %l[t_no]\n" @@ -406,7 +408,9 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) warn_pre_alternatives(); return false; #endif -#else /* GCC_VERSION >= 40500 */ + +#else /* CC_HAVE_ASM_GOTO */ + u8 flag; /* Open-coded due to __stringify() in ALTERNATIVE() */ asm volatile("1: movb $0,%0\n" @@ -427,7 +431,8 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) ".previous\n" : "=qm" (flag) : "i" (bit)); return flag; -#endif + +#endif /* CC_HAVE_ASM_GOTO */ } #define static_cpu_has(bit) \ @@ -441,7 +446,7 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) static __always_inline __pure bool _static_cpu_has_safe(u16 bit) { -#if __GNUC__ > 4 || __GNUC_MINOR__ >= 5 +#ifdef CC_HAVE_ASM_GOTO /* * We need to spell the jumps to the compiler because, depending on the offset, * the replacement jump can be bigger than the original jump, and this we cannot @@ -475,7 +480,7 @@ static __always_inline __pure bool _static_cpu_has_safe(u16 bit) return false; t_dynamic: return __static_cpu_has_safe(bit); -#else /* GCC_VERSION >= 40500 */ +#else u8 flag; /* Open-coded due to __stringify() in ALTERNATIVE() */ asm volatile("1: movb $2,%0\n" @@ -511,7 +516,7 @@ static __always_inline __pure bool _static_cpu_has_safe(u16 bit) : "=qm" (flag) : "i" (bit), "i" (X86_FEATURE_ALWAYS)); return (flag == 2 ? __static_cpu_has_safe(bit) : flag); -#endif +#endif /* CC_HAVE_ASM_GOTO */ } #define static_cpu_has_safe(bit) \ |