diff options
| -rw-r--r-- | include/libc-symbols.h | 13 | ||||
| -rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.c | 10 | ||||
| -rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.h | 22 |
3 files changed, 42 insertions, 3 deletions
diff --git a/include/libc-symbols.h b/include/libc-symbols.h index 68da77c58e..252141eb01 100644 --- a/include/libc-symbols.h +++ b/include/libc-symbols.h @@ -1,6 +1,6 @@ /* Support macros for making weak and strong aliases for symbols, and for using symbol sets and linker warnings with GNU ld. - Copyright (C) 1995-1998, 2000-2006, 2008 Free Software Foundation, Inc. + Copyright (C) 1995-1998,2000-2006,2008,2009 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -845,6 +845,17 @@ for linking") } \ __asm__ (".type " #name ", %gnu_indirect_function"); +/* The body of the function is supposed to use __get_cpu_features + which will, if necessary, initialize the data first. */ +#define libm_ifunc(name, expr) \ + extern void *name##_ifunc (void) __asm__ (#name); \ + void *name##_ifunc (void) \ + { \ + __typeof (name) *res = expr; \ + return res; \ + } \ + __asm__ (".type " #name ", %gnu_indirect_function"); + #ifdef HAVE_ASM_SET_DIRECTIVE # define libc_ifunc_hidden_def1(local, name) \ __asm__ (declare_symbol_alias_1_stringify (ASM_GLOBAL_DIRECTIVE) \ diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/init-arch.c index 35fd19af0e..49b421eac8 100644 --- a/sysdeps/x86_64/multiarch/init-arch.c +++ b/sysdeps/x86_64/multiarch/init-arch.c @@ -86,3 +86,13 @@ __init_cpu_features (void) else __cpu_features.kind = arch_kind_other; } + + +const struct cpu_features * +__get_cpu_features (void) +{ + if (__cpu_features.kind == arch_kind_unknown) + __init_cpu_features (); + + return &__cpu_features; +} diff --git a/sysdeps/x86_64/multiarch/init-arch.h b/sysdeps/x86_64/multiarch/init-arch.h index 48a2127418..0151e8b95b 100644 --- a/sysdeps/x86_64/multiarch/init-arch.h +++ b/sysdeps/x86_64/multiarch/init-arch.h @@ -54,10 +54,28 @@ extern void __init_cpu_features (void) attribute_hidden; __init_cpu_features (); \ while (0) +/* Used from outside libc.so to get access to the CPU features structure. */ +extern const struct cpu_features *__get_cpu_features (void) + __attribute__ ((const)); + /* Following are the feature tests used throughout libc. */ -#define HAS_POPCOUNT \ +#ifndef NOT_IN_libc +# define HAS_POPCOUNT \ ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 23)) != 0) -#define HAS_SSE4_2 \ +# define HAS_SSE4_2 \ ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 20)) != 0) + +# define HAS_FMA \ + ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 12)) != 0) +#else +# define HAS_POPCOUNT \ + ((__get_cpu_features ()->cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 23)) != 0) + +# define HAS_SSE4_2 \ + ((__get_cpu_features ()->cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 20)) != 0) + +# define HAS_FMA \ + ((__get_cpu_features ()->cpuid[COMMON_CPUID_INDEX_1].ecx & (1 << 12)) != 0) +#endif |