glibc/sysdeps/x86/cpu-features.h
H.J. Lu b9eb92ab05 Add Prefer_MAP_32BIT_EXEC to map executable pages with MAP_32BIT
According to Silvermont software optimization guide, for 64-bit
applications, branch prediction performance can be negatively impacted
when the target of a branch is more than 4GB away from the branch.  Add
the Prefer_MAP_32BIT_EXEC bit so that mmap will try to map executable
pages with MAP_32BIT first.  NB: MAP_32BIT will map to lower 2GB, not
lower 4GB, address.  Prefer_MAP_32BIT_EXEC reduces bits available for
address space layout randomization (ASLR), which is always disabled for
SUID programs and can only be enabled by setting environment variable,
LD_PREFER_MAP_32BIT_EXEC.

On Fedora 23, this patch speeds up GCC 5 testsuite by 3% on Silvermont.

	[BZ #19367]
	* sysdeps/unix/sysv/linux/wordsize-64/mmap.c: New file.
	* sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/mmap.c: Likewise.
	* sysdeps/x86/cpu-features.h (bit_Prefer_MAP_32BIT_EXEC): New.
	(index_Prefer_MAP_32BIT_EXEC): Likewise.
2015-12-15 13:16:02 -08:00

286 lines
9.7 KiB
C

/* This file is part of the GNU C Library.
Copyright (C) 2008-2015 Free Software Foundation, Inc.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef cpu_features_h
#define cpu_features_h
#define bit_Fast_Rep_String (1 << 0)
#define bit_Fast_Copy_Backward (1 << 1)
#define bit_Slow_BSF (1 << 2)
#define bit_Fast_Unaligned_Load (1 << 4)
#define bit_Prefer_PMINUB_for_stringop (1 << 5)
#define bit_AVX_Usable (1 << 6)
#define bit_FMA_Usable (1 << 7)
#define bit_FMA4_Usable (1 << 8)
#define bit_Slow_SSE4_2 (1 << 9)
#define bit_AVX2_Usable (1 << 10)
#define bit_AVX_Fast_Unaligned_Load (1 << 11)
#define bit_AVX512F_Usable (1 << 12)
#define bit_AVX512DQ_Usable (1 << 13)
#define bit_I586 (1 << 14)
#define bit_I686 (1 << 15)
#define bit_Prefer_MAP_32BIT_EXEC (1 << 16)
/* CPUID Feature flags. */
/* COMMON_CPUID_INDEX_1. */
#define bit_CX8 (1 << 8)
#define bit_CMOV (1 << 15)
#define bit_SSE2 (1 << 26)
#define bit_SSSE3 (1 << 9)
#define bit_SSE4_1 (1 << 19)
#define bit_SSE4_2 (1 << 20)
#define bit_OSXSAVE (1 << 27)
#define bit_AVX (1 << 28)
#define bit_POPCOUNT (1 << 23)
#define bit_FMA (1 << 12)
#define bit_FMA4 (1 << 16)
/* COMMON_CPUID_INDEX_7. */
#define bit_RTM (1 << 11)
#define bit_AVX2 (1 << 5)
#define bit_AVX512F (1 << 16)
#define bit_AVX512DQ (1 << 17)
/* XCR0 Feature flags. */
#define bit_XMM_state (1 << 1)
#define bit_YMM_state (2 << 1)
#define bit_Opmask_state (1 << 5)
#define bit_ZMM0_15_state (1 << 6)
#define bit_ZMM16_31_state (1 << 7)
/* The integer bit array index for the first set of internal feature bits. */
#define FEATURE_INDEX_1 0
/* The current maximum size of the feature integer bit array. */
#define FEATURE_INDEX_MAX 1
#ifdef __ASSEMBLER__
# include <ifunc-defines.h>
# include <rtld-global-offsets.h>
# define index_CX8 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_EDX_OFFSET
# define index_CMOV COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_EDX_OFFSET
# define index_SSE2 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_EDX_OFFSET
# define index_SSSE3 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
# define index_SSE4_1 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
# define index_SSE4_2 COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
# define index_AVX COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET
# define index_AVX2 COMMON_CPUID_INDEX_7*CPUID_SIZE+CPUID_EBX_OFFSET
# define index_Fast_Rep_String FEATURE_INDEX_1*FEATURE_SIZE
# define index_Fast_Copy_Backward FEATURE_INDEX_1*FEATURE_SIZE
# define index_Slow_BSF FEATURE_INDEX_1*FEATURE_SIZE
# define index_Fast_Unaligned_Load FEATURE_INDEX_1*FEATURE_SIZE
# define index_Prefer_PMINUB_for_stringop FEATURE_INDEX_1*FEATURE_SIZE
# define index_AVX_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_FMA_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_FMA4_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_Slow_SSE4_2 FEATURE_INDEX_1*FEATURE_SIZE
# define index_AVX2_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_AVX_Fast_Unaligned_Load FEATURE_INDEX_1*FEATURE_SIZE
# define index_AVX512F_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_AVX512DQ_Usable FEATURE_INDEX_1*FEATURE_SIZE
# define index_I586 FEATURE_INDEX_1*FEATURE_SIZE
# define index_I686 FEATURE_INDEX_1*FEATURE_SIZE
# define index_Prefer_MAP_32BIT_EXEC FEATURE_INDEX_1*FEATURE_SIZE
# if defined (_LIBC) && !IS_IN (nonlib)
# ifdef __x86_64__
# ifdef SHARED
# if IS_IN (rtld)
# define LOAD_RTLD_GLOBAL_RO_RDX
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), _rtld_local_ro+offset+(index_##name)(%rip)
# else
# define LOAD_RTLD_GLOBAL_RO_RDX \
mov _rtld_global_ro@GOTPCREL(%rip), %RDX_LP
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), \
RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET+offset+(index_##name)(%rdx)
# endif
# else /* SHARED */
# define LOAD_RTLD_GLOBAL_RO_RDX
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), _dl_x86_cpu_features+offset+(index_##name)(%rip)
# endif /* !SHARED */
# else /* __x86_64__ */
# ifdef SHARED
# define LOAD_FUNC_GOT_EAX(func) \
leal func@GOTOFF(%edx), %eax
# if IS_IN (rtld)
# define LOAD_GOT_AND_RTLD_GLOBAL_RO \
LOAD_PIC_REG(dx)
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), offset+(index_##name)+_rtld_local_ro@GOTOFF(%edx)
# else
# define LOAD_GOT_AND_RTLD_GLOBAL_RO \
LOAD_PIC_REG(dx); \
mov _rtld_global_ro@GOT(%edx), %ecx
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), \
RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET+offset+(index_##name)(%ecx)
# endif
# else /* SHARED */
# define LOAD_FUNC_GOT_EAX(func) \
leal func, %eax
# define LOAD_GOT_AND_RTLD_GLOBAL_RO
# define HAS_FEATURE(offset, name) \
testl $(bit_##name), _dl_x86_cpu_features+offset+(index_##name)
# endif /* !SHARED */
# endif /* !__x86_64__ */
# else /* _LIBC && !nonlib */
# error "Sorry, <cpu-features.h> is unimplemented for assembler"
# endif /* !_LIBC || nonlib */
/* HAS_* evaluates to true if we may use the feature at runtime. */
# define HAS_CPU_FEATURE(name) HAS_FEATURE (CPUID_OFFSET, name)
# define HAS_ARCH_FEATURE(name) HAS_FEATURE (FEATURE_OFFSET, name)
#else /* __ASSEMBLER__ */
enum
{
COMMON_CPUID_INDEX_1 = 0,
COMMON_CPUID_INDEX_7,
COMMON_CPUID_INDEX_80000001, /* for AMD */
/* Keep the following line at the end. */
COMMON_CPUID_INDEX_MAX
};
struct cpu_features
{
enum cpu_features_kind
{
arch_kind_unknown = 0,
arch_kind_intel,
arch_kind_amd,
arch_kind_other
} kind;
int max_cpuid;
struct cpuid_registers
{
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
} cpuid[COMMON_CPUID_INDEX_MAX];
unsigned int family;
unsigned int model;
unsigned int feature[FEATURE_INDEX_MAX];
};
/* Used from outside of glibc to get access to the CPU features
structure. */
extern const struct cpu_features *__get_cpu_features (void)
__attribute__ ((const));
# if defined (_LIBC) && !IS_IN (nonlib)
/* Unused for x86. */
# define INIT_ARCH()
# define __get_cpu_features() (&GLRO(dl_x86_cpu_features))
# endif
/* HAS_* evaluates to true if we may use the feature at runtime. */
# define HAS_CPU_FEATURE(name) \
((__get_cpu_features ()->cpuid[index_##name].reg_##name & (bit_##name)) != 0)
# define HAS_ARCH_FEATURE(name) \
((__get_cpu_features ()->feature[index_##name] & (bit_##name)) != 0)
# define index_CX8 COMMON_CPUID_INDEX_1
# define index_CMOV COMMON_CPUID_INDEX_1
# define index_SSE2 COMMON_CPUID_INDEX_1
# define index_SSSE3 COMMON_CPUID_INDEX_1
# define index_SSE4_1 COMMON_CPUID_INDEX_1
# define index_SSE4_2 COMMON_CPUID_INDEX_1
# define index_AVX COMMON_CPUID_INDEX_1
# define index_AVX2 COMMON_CPUID_INDEX_7
# define index_AVX512F COMMON_CPUID_INDEX_7
# define index_AVX512DQ COMMON_CPUID_INDEX_7
# define index_RTM COMMON_CPUID_INDEX_7
# define index_FMA COMMON_CPUID_INDEX_1
# define index_FMA4 COMMON_CPUID_INDEX_80000001
# define index_POPCOUNT COMMON_CPUID_INDEX_1
# define index_OSXSAVE COMMON_CPUID_INDEX_1
# define reg_CX8 edx
# define reg_CMOV edx
# define reg_SSE2 edx
# define reg_SSSE3 ecx
# define reg_SSE4_1 ecx
# define reg_SSE4_2 ecx
# define reg_AVX ecx
# define reg_AVX2 ebx
# define reg_AVX512F ebx
# define reg_AVX512DQ ebx
# define reg_RTM ebx
# define reg_FMA ecx
# define reg_FMA4 ecx
# define reg_POPCOUNT ecx
# define reg_OSXSAVE ecx
# define index_Fast_Rep_String FEATURE_INDEX_1
# define index_Fast_Copy_Backward FEATURE_INDEX_1
# define index_Slow_BSF FEATURE_INDEX_1
# define index_Fast_Unaligned_Load FEATURE_INDEX_1
# define index_Prefer_PMINUB_for_stringop FEATURE_INDEX_1
# define index_AVX_Usable FEATURE_INDEX_1
# define index_FMA_Usable FEATURE_INDEX_1
# define index_FMA4_Usable FEATURE_INDEX_1
# define index_Slow_SSE4_2 FEATURE_INDEX_1
# define index_AVX2_Usable FEATURE_INDEX_1
# define index_AVX_Fast_Unaligned_Load FEATURE_INDEX_1
# define index_AVX512F_Usable FEATURE_INDEX_1
# define index_AVX512DQ_Usable FEATURE_INDEX_1
# define index_I586 FEATURE_INDEX_1
# define index_I686 FEATURE_INDEX_1
# define index_Prefer_MAP_32BIT_EXEC FEATURE_INDEX_1
#endif /* !__ASSEMBLER__ */
#ifdef __x86_64__
# define HAS_CPUID 1
#elif defined __i586__ || defined __pentium__
# define HAS_CPUID 1
# define HAS_I586 1
# define HAS_I686 HAS_ARCH_FEATURE (I686)
#elif (defined __i686__ || defined __pentiumpro__ \
|| defined __pentium4__ || defined __nocona__ \
|| defined __atom__ || defined __core2__ \
|| defined __corei7__ || defined __corei7_avx__ \
|| defined __core_avx2__ || defined __nehalem__ \
|| defined __sandybridge__ || defined __haswell__ \
|| defined __knl__ || defined __bonnell__ \
|| defined __silvermont__ \
|| defined __k6__ || defined __k8__ \
|| defined __athlon__ || defined __amdfam10__ \
|| defined __bdver1__ || defined __bdver2__ \
|| defined __bdver3__ || defined __bdver4__ \
|| defined __btver1__ || defined __btver2__)
# define HAS_CPUID 1
# define HAS_I586 1
# define HAS_I686 1
#else
# define HAS_CPUID 0
# define HAS_I586 HAS_ARCH_FEATURE (I586)
# define HAS_I686 HAS_ARCH_FEATURE (I686)
#endif
#endif /* cpu_features_h */