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author | Carlos O'Donell <carlos_odonell@mentor.com> | 2012-05-16 20:14:24 -0700 |
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committer | Carlos O'Donell <carlos_odonell@mentor.com> | 2012-05-17 06:59:28 -0700 |
commit | 1a0994f5356214e8af8a1c1cc33fbf74a7ac8993 (patch) | |
tree | 99ce1f919a2509868a71f4262f055b5eec9accb0 /sysdeps/x86_64 | |
parent | 0af797def371ceb4f05586d7bcd25841653d2082 (diff) | |
download | glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.tar.gz glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.tar.xz glibc-1a0994f5356214e8af8a1c1cc33fbf74a7ac8993.zip |
BZ#14059: Fix AVX and FMA4 detection.
Fix AVX and FMA4 detection by following the guidelines set out by Intel and AMD for detecting these features.
Diffstat (limited to 'sysdeps/x86_64')
-rw-r--r-- | sysdeps/x86_64/multiarch/Makefile | 1 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.c | 27 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.h | 51 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/strcmp.S | 9 | ||||
-rw-r--r-- | sysdeps/x86_64/multiarch/test-multiarch.c | 90 |
5 files changed, 148 insertions, 30 deletions
diff --git a/sysdeps/x86_64/multiarch/Makefile b/sysdeps/x86_64/multiarch/Makefile index 9a183f068e..dd6c27d0b4 100644 --- a/sysdeps/x86_64/multiarch/Makefile +++ b/sysdeps/x86_64/multiarch/Makefile @@ -1,5 +1,6 @@ ifeq ($(subdir),csu) aux += init-arch +tests += test-multiarch gen-as-const-headers += ifunc-defines.sym endif diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/init-arch.c index 80527ec59d..fb44dcfcf6 100644 --- a/sysdeps/x86_64/multiarch/init-arch.c +++ b/sysdeps/x86_64/multiarch/init-arch.c @@ -1,6 +1,6 @@ /* Initialize CPU feature data. This file is part of the GNU C Library. - Copyright (C) 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. + Copyright (C) 2008-2012 Free Software Foundation, Inc. Contributed by Ulrich Drepper <drepper@redhat.com>. The GNU C Library is free software; you can redistribute it and/or @@ -143,16 +143,23 @@ __init_cpu_features (void) else kind = arch_kind_other; - if (__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & bit_AVX) + /* Can we call xgetbv? */ + if (CPUID_OSXSAVE) { - /* Reset the AVX bit in case OSXSAVE is disabled. */ - if ((__cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx & bit_OSXSAVE) != 0 - && ({ unsigned int xcrlow; - unsigned int xcrhigh; - asm ("xgetbv" - : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0)); - (xcrlow & 6) == 6; })) - __cpu_features.feature[index_YMM_Usable] |= bit_YMM_Usable; + unsigned int xcrlow; + unsigned int xcrhigh; + asm ("xgetbv" : "=a" (xcrlow), "=d" (xcrhigh) : "c" (0)); + /* Is YMM and XMM state usable? */ + if ((xcrlow & (bit_YMM_state | bit_XMM_state)) == + (bit_YMM_state | bit_XMM_state)) + { + /* Determine if AVX is usable. */ + if (CPUID_AVX) + __cpu_features.feature[index_AVX_Usable] |= bit_AVX_Usable; + /* Determine if FMA4 is usable. */ + if (CPUID_FMA4) + __cpu_features.feature[index_FMA4_Usable] |= bit_FMA4_Usable; + } } __cpu_features.family = family; diff --git a/sysdeps/x86_64/multiarch/init-arch.h b/sysdeps/x86_64/multiarch/init-arch.h index 5054e46f61..45e2651678 100644 --- a/sysdeps/x86_64/multiarch/init-arch.h +++ b/sysdeps/x86_64/multiarch/init-arch.h @@ -1,5 +1,5 @@ /* This file is part of the GNU C Library. - Copyright (C) 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc. + Copyright (C) 2008-2012 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 @@ -21,8 +21,10 @@ #define bit_Prefer_SSE_for_memop (1 << 3) #define bit_Fast_Unaligned_Load (1 << 4) #define bit_Prefer_PMINUB_for_stringop (1 << 5) -#define bit_YMM_Usable (1 << 6) +#define bit_AVX_Usable (1 << 6) +#define bit_FMA4_Usable (1 << 7) +/* CPUID Feature flags. */ #define bit_SSE2 (1 << 26) #define bit_SSSE3 (1 << 9) #define bit_SSE4_1 (1 << 19) @@ -33,6 +35,10 @@ #define bit_FMA (1 << 12) #define bit_FMA4 (1 << 16) +/* XCR0 Feature flags. */ +#define bit_XMM_state (1 << 1) +#define bit_YMM_state (2 << 1) + #ifdef __ASSEMBLER__ # include <ifunc-defines.h> @@ -49,7 +55,8 @@ # define index_Prefer_SSE_for_memop 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_YMM_Usable FEATURE_INDEX_1*FEATURE_SIZE +# define index_AVX_Usable FEATURE_INDEX_1*FEATURE_SIZE +# define index_FMA4_Usable FEATURE_INDEX_1*FEATURE_SIZE #else /* __ASSEMBLER__ */ @@ -113,35 +120,45 @@ extern const struct cpu_features *__get_cpu_features (void) /* Following are the feature tests used throughout libc. */ +/* CPUID_* evaluates to true if the feature flag is enabled. + We always use &__cpu_features because the HAS_CPUID_* macros + are called only within __init_cpu_features, where we can't + call __get_cpu_features without infinite recursion. */ +# define HAS_CPUID_FLAG(idx, reg, bit) \ + (((&__cpu_features)->cpuid[idx].reg & (bit)) != 0) + +# define CPUID_OSXSAVE \ + HAS_CPUID_FLAG (COMMON_CPUID_INDEX_1, ecx, bit_OSXSAVE) +# define CPUID_AVX \ + HAS_CPUID_FLAG (COMMON_CPUID_INDEX_1, ecx, bit_AVX) +# define CPUID_FMA4 \ + HAS_CPUID_FLAG (COMMON_CPUID_INDEX_80000001, ecx, bit_FMA4) + +/* HAS_* evaluates to true if we may use the feature at runtime. */ # define HAS_SSE2 HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, edx, bit_SSE2) # define HAS_POPCOUNT HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_POPCOUNT) # define HAS_SSSE3 HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_SSSE3) # define HAS_SSE4_1 HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_SSE4_1) # define HAS_SSE4_2 HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_SSE4_2) # define HAS_FMA HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_FMA) -# define HAS_AVX HAS_CPU_FEATURE (COMMON_CPUID_INDEX_1, ecx, bit_AVX) -# define HAS_FMA4 HAS_CPU_FEATURE (COMMON_CPUID_INDEX_80000001, ecx, bit_FMA4) # 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_Prefer_SSE_for_memop FEATURE_INDEX_1 # define index_Fast_Unaligned_Load FEATURE_INDEX_1 -# define index_YMM_Usable FEATURE_INDEX_1 +# define index_AVX_Usable FEATURE_INDEX_1 +# define index_FMA4_Usable FEATURE_INDEX_1 # define HAS_ARCH_FEATURE(name) \ ((__get_cpu_features ()->feature[index_##name] & (bit_##name)) != 0) -# define HAS_FAST_REP_STRING HAS_ARCH_FEATURE (Fast_Rep_String) - -# define HAS_FAST_COPY_BACKWARD HAS_ARCH_FEATURE (Fast_Copy_Backward) - -# define HAS_SLOW_BSF HAS_ARCH_FEATURE (Slow_BSF) - -# define HAS_PREFER_SSE_FOR_MEMOP HAS_ARCH_FEATURE (Prefer_SSE_for_memop) - -# define HAS_FAST_UNALIGNED_LOAD HAS_ARCH_FEATURE (Fast_Unaligned_Load) - -# define HAS_YMM_USABLE HAS_ARCH_FEATURE (YMM_Usable) +# define HAS_FAST_REP_STRING HAS_ARCH_FEATURE (Fast_Rep_String) +# define HAS_FAST_COPY_BACKWARD HAS_ARCH_FEATURE (Fast_Copy_Backward) +# define HAS_SLOW_BSF HAS_ARCH_FEATURE (Slow_BSF) +# define HAS_PREFER_SSE_FOR_MEMOP HAS_ARCH_FEATURE (Prefer_SSE_for_memop) +# define HAS_FAST_UNALIGNED_LOAD HAS_ARCH_FEATURE (Fast_Unaligned_Load) +# define HAS_AVX HAS_ARCH_FEATURE (AVX_Usable) +# define HAS_FMA4 HAS_ARCH_FEATURE (FMA4_Usable) #endif /* __ASSEMBLER__ */ diff --git a/sysdeps/x86_64/multiarch/strcmp.S b/sysdeps/x86_64/multiarch/strcmp.S index 2b9870ba93..d366d09690 100644 --- a/sysdeps/x86_64/multiarch/strcmp.S +++ b/sysdeps/x86_64/multiarch/strcmp.S @@ -1,5 +1,5 @@ /* strcmp with SSE4.2 - Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc. + Copyright (C) 2009-2012 Free Software Foundation, Inc. Contributed by Intel Corporation. This file is part of the GNU C Library. @@ -83,6 +83,7 @@ .text ENTRY(STRCMP) .type STRCMP, @gnu_indirect_function + /* Manually inlined call to __get_cpu_features. */ cmpl $0, __cpu_features+KIND_OFFSET(%rip) jne 1f call __init_cpu_features @@ -100,13 +101,14 @@ END(STRCMP) # ifdef USE_AS_STRCASECMP_L ENTRY(__strcasecmp) .type __strcasecmp, @gnu_indirect_function + /* Manually inlined call to __get_cpu_features. */ cmpl $0, __cpu_features+KIND_OFFSET(%rip) jne 1f call __init_cpu_features 1: # ifdef HAVE_AVX_SUPPORT leaq __strcasecmp_avx(%rip), %rax - testl $bit_AVX, __cpu_features+CPUID_OFFSET+index_AVX(%rip) + testl $bit_AVX_Usable, __cpu_features+FEATURE_OFFSET+index_AVX_Usable(%rip) jnz 2f # endif leaq __strcasecmp_sse42(%rip), %rax @@ -123,13 +125,14 @@ weak_alias (__strcasecmp, strcasecmp) # ifdef USE_AS_STRNCASECMP_L ENTRY(__strncasecmp) .type __strncasecmp, @gnu_indirect_function + /* Manually inlined call to __get_cpu_features. */ cmpl $0, __cpu_features+KIND_OFFSET(%rip) jne 1f call __init_cpu_features 1: # ifdef HAVE_AVX_SUPPORT leaq __strncasecmp_avx(%rip), %rax - testl $bit_AVX, __cpu_features+CPUID_OFFSET+index_AVX(%rip) + testl $bit_AVX_Usable, __cpu_features+FEATURE_OFFSET+index_AVX_Usable(%rip) jnz 2f # endif leaq __strncasecmp_sse42(%rip), %rax diff --git a/sysdeps/x86_64/multiarch/test-multiarch.c b/sysdeps/x86_64/multiarch/test-multiarch.c new file mode 100644 index 0000000000..76b1af2f8c --- /dev/null +++ b/sysdeps/x86_64/multiarch/test-multiarch.c @@ -0,0 +1,90 @@ +/* Test CPU feature data. + This file is part of the GNU C Library. + Copyright (C) 2012 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/>. */ + +#include <init-arch.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +static char *cpu_flags; + +/* Search for flags in /proc/cpuinfo and store line + in cpu_flags. */ +void +get_cpuinfo (void) +{ + FILE *f; + char *line = NULL; + size_t len = 0; + ssize_t read; + + f = fopen ("/proc/cpuinfo", "r"); + if (f == NULL) + { + printf ("cannot open /proc/cpuinfo"); + exit (1); + } + + while ((read = getline (&line, &len, f)) != -1) + { + if (strncmp (line, "flags", 5) == 0) + { + cpu_flags = strdup (line); + break; + } + } + fclose (f); + free (line); +} + +int +check_proc (const char *proc_name, int flag, const char *name) +{ + int found = 0; + + printf ("Checking %s:\n", name); + printf (" init-arch %d\n", flag); + if (strstr (cpu_flags, proc_name) != NULL) + found = 1; + printf (" cpuinfo (%s) %d\n", proc_name, found); + + if (found != flag) + printf (" *** failure ***\n"); + + return (found != flag); +} + +static int +do_test (int argc, char **argv) +{ + int fails; + + get_cpuinfo (); + fails = check_proc ("avx", HAS_AVX, "HAS_AVX"); + fails += check_proc ("fma4", HAS_FMA4, "HAS_FMA4"); + fails += check_proc ("sse4_2", HAS_SSE4_2, "HAS_SSE4_2"); + fails += check_proc ("sse4_1", HAS_SSE4_1, "HAS_SSE4_1"); + fails += check_proc ("ssse3", HAS_SSSE3, "HAS_SSSE3"); + fails += check_proc ("popcnt", HAS_POPCOUNT, "HAS_POPCOUNT"); + + printf ("%d differences between /proc/cpuinfo and glibc code.\n", fails); + + return (fails != 0); +} + +#include "../../../test-skeleton.c" |