From: Adhemerval Zanella Date: Mon, 6 Nov 2023 20:25:42 +0000 (-0300) Subject: x86: Use dl-symbol-redir-ifunc.h on cpu-tunables X-Git-Tag: upstream/2.39~254 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4862d546c04bd2caf496d48335a546c0a44ad4a5;p=platform%2Fupstream%2Fglibc.git x86: Use dl-symbol-redir-ifunc.h on cpu-tunables The dl-symbol-redir-ifunc.h redirects compiler-generated libcalls to arch-specific memory implementations to avoid ifunc calls where it is not yet possible. The memcmp-isa-default-impl.h aims to fix the same issue by calling the specific memset implementation directly. Using the memcmp symbol directly allows the compiler to inline the memset calls (especially because _dl_tunable_set_hwcaps uses constants values), generating better code. Checked on x86_64-linux-gnu. Reviewed-by: Noah Goldstein Reviewed-by: Siddhesh Poyarekar --- diff --git a/sysdeps/i386/i686/multiarch/dl-symbol-redir-ifunc.h b/sysdeps/i386/i686/multiarch/dl-symbol-redir-ifunc.h index dee69d1..220c586 100644 --- a/sysdeps/i386/i686/multiarch/dl-symbol-redir-ifunc.h +++ b/sysdeps/i386/i686/multiarch/dl-symbol-redir-ifunc.h @@ -19,6 +19,11 @@ #ifndef _DL_IFUNC_GENERIC_H #define _DL_IFUNC_GENERIC_H +#ifndef SHARED + asm ("memset = __memset_ia32"); +asm ("memcmp = __memcmp_ia32"); + +#endif /* SHARED */ #endif diff --git a/sysdeps/x86/cpu-tunables.c b/sysdeps/x86/cpu-tunables.c index 0d4f328..5697885 100644 --- a/sysdeps/x86/cpu-tunables.c +++ b/sysdeps/x86/cpu-tunables.c @@ -24,24 +24,11 @@ #include #include #include - -/* We can't use IFUNC memcmp nor strlen in init_cpu_features from libc.a - since IFUNC must be set up by init_cpu_features. */ -#if defined USE_MULTIARCH && !defined SHARED -# ifdef __x86_64__ -/* DEFAULT_MEMCMP by sysdeps/x86_64/memcmp-isa-default-impl.h. */ -# include -# else -# define DEFAULT_MEMCMP __memcmp_ia32 -# endif -extern __typeof (memcmp) DEFAULT_MEMCMP; -#else -# define DEFAULT_MEMCMP memcmp -#endif +#include #define CHECK_GLIBC_IFUNC_CPU_OFF(f, cpu_features, name, len) \ _Static_assert (sizeof (#name) - 1 == len, #name " != " #len); \ - if (!DEFAULT_MEMCMP (f, #name, len)) \ + if (memcmp (f, #name, len) == 0) \ { \ CPU_FEATURE_UNSET (cpu_features, name) \ break; \ @@ -51,7 +38,7 @@ extern __typeof (memcmp) DEFAULT_MEMCMP; which isn't available. */ #define CHECK_GLIBC_IFUNC_PREFERRED_OFF(f, cpu_features, name, len) \ _Static_assert (sizeof (#name) - 1 == len, #name " != " #len); \ - if (!DEFAULT_MEMCMP (f, #name, len)) \ + if (memcmp (f, #name, len) == 0) \ { \ cpu_features->preferred[index_arch_##name] \ &= ~bit_arch_##name; \ @@ -62,7 +49,7 @@ extern __typeof (memcmp) DEFAULT_MEMCMP; #define CHECK_GLIBC_IFUNC_PREFERRED_BOTH(f, cpu_features, name, \ disable, len) \ _Static_assert (sizeof (#name) - 1 == len, #name " != " #len); \ - if (!DEFAULT_MEMCMP (f, #name, len)) \ + if (memcmp (f, #name, len) == 0) \ { \ if (disable) \ cpu_features->preferred[index_arch_##name] &= ~bit_arch_##name; \ @@ -76,7 +63,7 @@ extern __typeof (memcmp) DEFAULT_MEMCMP; #define CHECK_GLIBC_IFUNC_PREFERRED_NEED_BOTH(f, cpu_features, name, \ need, disable, len) \ _Static_assert (sizeof (#name) - 1 == len, #name " != " #len); \ - if (!DEFAULT_MEMCMP (f, #name, len)) \ + if (memcmp (f, #name, len) == 0) \ { \ if (disable) \ cpu_features->preferred[index_arch_##name] &= ~bit_arch_##name; \ @@ -177,7 +164,7 @@ TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *valp) CHECK_GLIBC_IFUNC_CPU_OFF (n, cpu_features, POPCNT, 6); CHECK_GLIBC_IFUNC_CPU_OFF (n, cpu_features, SSE4_1, 6); CHECK_GLIBC_IFUNC_CPU_OFF (n, cpu_features, SSE4_2, 6); - if (!DEFAULT_MEMCMP (n, "XSAVEC", 6)) + if (memcmp (n, "XSAVEC", 6) == 0) { /* Update xsave_state_size to XSAVE state size. */ cpu_features->xsave_state_size @@ -290,12 +277,11 @@ attribute_hidden void TUNABLE_CALLBACK (set_x86_ibt) (tunable_val_t *valp) { - if (DEFAULT_MEMCMP (valp->strval, "on", sizeof ("on")) == 0) + if (memcmp (valp->strval, "on", sizeof ("on")) == 0) GL(dl_x86_feature_control).ibt = cet_always_on; - else if (DEFAULT_MEMCMP (valp->strval, "off", sizeof ("off")) == 0) + else if (memcmp (valp->strval, "off", sizeof ("off")) == 0) GL(dl_x86_feature_control).ibt = cet_always_off; - else if (DEFAULT_MEMCMP (valp->strval, "permissive", - sizeof ("permissive")) == 0) + else if (memcmp (valp->strval, "permissive", sizeof ("permissive")) == 0) GL(dl_x86_feature_control).ibt = cet_permissive; } @@ -303,12 +289,11 @@ attribute_hidden void TUNABLE_CALLBACK (set_x86_shstk) (tunable_val_t *valp) { - if (DEFAULT_MEMCMP (valp->strval, "on", sizeof ("on")) == 0) + if (memcmp (valp->strval, "on", sizeof ("on")) == 0) GL(dl_x86_feature_control).shstk = cet_always_on; - else if (DEFAULT_MEMCMP (valp->strval, "off", sizeof ("off")) == 0) + else if (memcmp (valp->strval, "off", sizeof ("off")) == 0) GL(dl_x86_feature_control).shstk = cet_always_off; - else if (DEFAULT_MEMCMP (valp->strval, "permissive", - sizeof ("permissive")) == 0) + else if (memcmp (valp->strval, "permissive", sizeof ("permissive")) == 0) GL(dl_x86_feature_control).shstk = cet_permissive; } #endif diff --git a/sysdeps/x86_64/memcmp-isa-default-impl.h b/sysdeps/x86_64/memcmp-isa-default-impl.h deleted file mode 100644 index 0962e83..0000000 --- a/sysdeps/x86_64/memcmp-isa-default-impl.h +++ /dev/null @@ -1,28 +0,0 @@ -/* Set default memcmp impl based on ISA level. - Copyright (C) 2022-2023 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 - 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 - . */ - -#include -#if MINIMUM_X86_ISA_LEVEL == 1 || MINIMUM_X86_ISA_LEVEL == 2 -# define DEFAULT_MEMCMP __memcmp_sse2 -#elif MINIMUM_X86_ISA_LEVEL == 3 -# define DEFAULT_MEMCMP __memcmp_avx2_movbe -#elif MINIMUM_X86_ISA_LEVEL == 4 -# define DEFAULT_MEMCMP __memcmp_evex_movbe -#else -# error "Unknown default memcmp implementation" -#endif diff --git a/sysdeps/x86_64/multiarch/dl-symbol-redir-ifunc.h b/sysdeps/x86_64/multiarch/dl-symbol-redir-ifunc.h index 3fe73ca..c7d8961 100644 --- a/sysdeps/x86_64/multiarch/dl-symbol-redir-ifunc.h +++ b/sysdeps/x86_64/multiarch/dl-symbol-redir-ifunc.h @@ -19,6 +19,8 @@ #ifndef _DL_IFUNC_GENERIC_H #define _DL_IFUNC_GENERIC_H +#ifndef SHARED + #include #if MINIMUM_X86_ISA_LEVEL >= 4 @@ -31,4 +33,17 @@ asm ("memset = " HAVE_MEMSET_IFUNC_GENERIC); + +#if MINIMUM_X86_ISA_LEVEL >= 4 +# define HAVE_MEMCMP_IFUNC_GENERIC "__memcmp_evex_movbe" +#elif MINIMUM_X86_ISA_LEVEL == 3 +# define HAVE_MEMCMP_IFUNC_GENERIC "__memcmp_avx2_movbe" +#else +# define HAVE_MEMCMP_IFUNC_GENERIC "__memcmp_sse2" +#endif + +asm ("memcmp = " HAVE_MEMCMP_IFUNC_GENERIC); + +#endif /* SHARED */ + #endif