V6: [PATCH] x86: Install <sys/platform/x86.h> [BZ #26124]
H.J. Lu
hjl.tools@gmail.com
Thu Jun 25 13:20:23 GMT 2020
On Thu, Jun 25, 2020 at 05:30:59AM -0700, H.J. Lu wrote:
> On Thu, Jun 25, 2020 at 09:33:26AM +0200, Florian Weimer wrote:
> > * H. J. Lu via Libc-alpha:
> >
> > >> is not expected to be extendable. The macro API is not my favorite way of
> > >
> > > We can expand the cpuid array. We just need to add an alias to
> > > __x86_get_cpu_features
> > > with a new symbol version.
> >
> > Agreed, from a GNU gABI perspective.
> >
> > However, for some distributions, this requirement will put hardware
> > enablement for new CPUs on hold until we have reworked our package
> > dependency generation, so that we can express symbol-specific version
> > information. Debian & downstreams can already do this, with some manual
> > work, but Fedora & downstreams can only express versions on sonames.
> > (Without these changes, we would have to backport the entire GLIBC_2.33
> > symbol set to get __x86_get_cpu_features@GLIBC_2.33, for example. This
> > is not something we will be able to do in all cases, depending on the
> > other changes that are going in.)
> >
> > Even then, we can only backport such changes if a glibc release has
> > happened (so that we can be sure that the meaning of the symbol version
> > will not change again).
> >
> > My proposal, where the index is passed to the function and the function
> > returns the flag word, does not have these issues: old glibcs will
> > simply return 0 flags, and the feature appears unusable/unavailable.
> > This is what already happens with your approach, too, if we use more
> > bits inside the existing array elements.
> >
> > I'm not entirely opposed to enhancing the RPM dependency generation, but
> > I already tried once and couldn't get it done, and if I fail again, it
> > might seriously impact CPU hardware enablement in Red Hat Enterprise
> > Linux 9. I hope this explains my reservations about this interface
> > design.
> >
>
> Thanks for your detailed explanation. Here is the revised patch.
> COMMON_CPUID_INDEX_MAX and USABLE_FEATURE_INDEX_MAX are passed to
> __x86_get_cpu_features so that when USABLE_FEATURE_INDEX_MAX or
> COMMON_CPUID_INDEX_MAX are increased to support new processor features,
> __x86_get_cpu_features in the older glibc binaries returns NULL and
> HAS_CPU_FEATURE/CPU_FEATURE_USABLE return falses on the new processor
> feature. No new symbol version is neeeded.
>
> Any comments?
>
Small update:
const struct cpu_features *
__x86_get_cpu_features (unsigned int max, int cpuid)
{
if (cpuid)
{
if (max > COMMON_CPUID_INDEX_MAX)
return NULL;
}
else if (max > USABLE_FEATURE_INDEX_MAX)
return NULL;
return &GLRO(dl_x86_cpu_features);
}
Don't return NULL when checking the cpuid array when COMMON_CPUID_INDEX_MAX
is unchanged, but USABLE_FEATURE_INDEX_MAX is changed.
H.J.
---
Install <sys/platform/x86.h> so that programmers can do
#if __has_include(<sys/platform/x86.h>)
#include <sys/platform/x86.h>
#endif
...
if (HAS_CPU_FEATURE (SSE2))
...
if (CPU_FEATURE_USABLE (AVX2))
...
<sys/platform/x86.h> exports only:
enum
{
/* The integer bit array index for the first set of usable feature
bits. */
USABLE_FEATURE_INDEX_1 = 0,
/* The current maximum size of the feature integer bit array. */
USABLE_FEATURE_INDEX_MAX
};
enum
{
COMMON_CPUID_INDEX_1 = 0,
COMMON_CPUID_INDEX_7,
COMMON_CPUID_INDEX_80000001,
COMMON_CPUID_INDEX_D_ECX_1,
COMMON_CPUID_INDEX_80000007,
COMMON_CPUID_INDEX_80000008,
COMMON_CPUID_INDEX_7_ECX_1,
/* Keep the following line at the end. */
COMMON_CPUID_INDEX_MAX
};
struct cpu_features
{
struct cpu_features_basic basic;
unsigned int *usable_p;
struct cpuid_registers cpuid[COMMON_CPUID_INDEX_MAX];
};
/* Get a pointer to the CPU features structure. */
extern const struct cpu_features *__x86_get_cpu_features
(unsigned int max, int cpuid) __attribute__ ((const));
Since all feature checks are done through macros, programs compiled with
a newer <sys/platform/x86.h> are compatible with the older glibc binaries
as long as the layout of struct cpu_features is identical. The cpuid
array can be expanded with backward binary compatibility for both .o and
.so files. When USABLE_FEATURE_INDEX_MAX or COMMON_CPUID_INDEX_MAX are
increased to support new processor features, __x86_get_cpu_features in the
older glibc binaries returns NULL and HAS_CPU_FEATURE/CPU_FEATURE_USABLE
return falses on the new processor feature. No new symbol version is
neeeded.
Note: Although GCC has __builtin_cpu_supports, it only supports a subset
of <sys/platform/x86.h> and it is equivalent to CPU_FEATURE_USABLE. It
doesn't support HAS_CPU_FEATURE.
---
NEWS | 2 +
manual/platform.texi | 27 +++
sysdeps/unix/sysv/linux/i386/ld.abilist | 1 +
sysdeps/unix/sysv/linux/x86_64/64/ld.abilist | 1 +
sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist | 1 +
sysdeps/x86/Makefile | 1 +
sysdeps/x86/Versions | 4 +-
sysdeps/x86/dl-get-cpu-features.c | 11 +-
sysdeps/x86/include/cpu-features.h | 209 ++++++++++++++++++
.../{cpu-features.h => sys/platform/x86.h} | 183 ++-------------
sysdeps/x86/tst-get-cpu-features.c | 6 +-
sysdeps/x86_64/fpu/math-tests-arch.h | 8 +-
sysdeps/x86_64/multiarch/test-multiarch.c | 10 +-
13 files changed, 286 insertions(+), 178 deletions(-)
create mode 100644 sysdeps/x86/include/cpu-features.h
rename sysdeps/x86/{cpu-features.h => sys/platform/x86.h} (77%)
diff --git a/NEWS b/NEWS
index a660fc59a8..ae7d1ece35 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,8 @@ Version 2.32
Major new features:
+* Add <sys/platform/x86.h> to provide query macros for x86 CPU features.
+
* Unicode 12.1.0 Support: Character encoding, character type info, and
transliteration tables are all updated to Unicode 12.1.0, using
generator scripts contributed by Mike FABIAN (Red Hat).
diff --git a/manual/platform.texi b/manual/platform.texi
index 504addc956..6c7cad9792 100644
--- a/manual/platform.texi
+++ b/manual/platform.texi
@@ -7,6 +7,7 @@
@menu
* PowerPC:: Facilities Specific to the PowerPC Architecture
* RISC-V:: Facilities Specific to the RISC-V Architecture
+* X86:: Facilities Specific to the X86 Architecture
@end menu
@node PowerPC
@@ -134,3 +135,29 @@ all threads in the current process. Setting the
ordering on only the current thread is necessary. All other flag bits are
reserved.
@end deftypefun
+
+@node X86
+@appendixsec X86-specific Facilities
+
+Facilities specific to X86 that are not specific to a particular
+operating system are declared in @file{sys/platform/x86.h}.
+
+@deftypefun {const struct cpu_features *} __x86_get_cpu_features
+(unsigned int @var{max}, int @var{cpuid})
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
+Return a pointer to x86 CPU feature structure used by query macros for x86
+CPU features. If @var{cpuid} is non-zero and @var{max} exceeds
+@code{COMMON_CPUID_INDEX_MAX}, the function returns @code{NULL}. If
+@var{cpuid} is zero and @var{max} exceeds
+@code{USABLE_FEATURE_INDEX_MAX}, the function returns @code{NULL}.
+@end deftypefun
+
+@deftypefn Macro int HAS_CPU_FEATURE (@var{name})
+This macro returns a nonzero value (true) if the processor has the feature
+@var{name}.
+@end deftypefn
+
+@deftypefn Macro int CPU_FEATURE_USABLE (@var{name})
+This macro returns a nonzero value (true) if the processor has the feature
+@var{name} and the feature is supported by the operating system.
+@end deftypefn
diff --git a/sysdeps/unix/sysv/linux/i386/ld.abilist b/sysdeps/unix/sysv/linux/i386/ld.abilist
index 0478e22071..1226876689 100644
--- a/sysdeps/unix/sysv/linux/i386/ld.abilist
+++ b/sysdeps/unix/sysv/linux/i386/ld.abilist
@@ -3,3 +3,4 @@ GLIBC_2.1 __libc_stack_end D 0x4
GLIBC_2.1 _dl_mcount F
GLIBC_2.3 ___tls_get_addr F
GLIBC_2.3 __tls_get_addr F
+GLIBC_2.32 __x86_get_cpu_features F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
index d3cdf7611e..886e57abd5 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
@@ -2,3 +2,4 @@ GLIBC_2.2.5 __libc_stack_end D 0x8
GLIBC_2.2.5 _dl_mcount F
GLIBC_2.2.5 _r_debug D 0x28
GLIBC_2.3 __tls_get_addr F
+GLIBC_2.32 __x86_get_cpu_features F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
index c70bccf782..0d2f8a2cc5 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
@@ -2,3 +2,4 @@ GLIBC_2.16 __libc_stack_end D 0x4
GLIBC_2.16 __tls_get_addr F
GLIBC_2.16 _dl_mcount F
GLIBC_2.16 _r_debug D 0x14
+GLIBC_2.32 __x86_get_cpu_features F
diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
index beab426f67..0e4d132803 100644
--- a/sysdeps/x86/Makefile
+++ b/sysdeps/x86/Makefile
@@ -4,6 +4,7 @@ endif
ifeq ($(subdir),elf)
sysdep-dl-routines += dl-get-cpu-features
+sysdep_headers += sys/platform/x86.h
tests += tst-get-cpu-features tst-get-cpu-features-static
tests-static += tst-get-cpu-features-static
diff --git a/sysdeps/x86/Versions b/sysdeps/x86/Versions
index e02923708e..7e3139dbb1 100644
--- a/sysdeps/x86/Versions
+++ b/sysdeps/x86/Versions
@@ -1,5 +1,5 @@
ld {
- GLIBC_PRIVATE {
- __get_cpu_features;
+ GLIBC_2.32 {
+ __x86_get_cpu_features;
}
}
diff --git a/sysdeps/x86/dl-get-cpu-features.c b/sysdeps/x86/dl-get-cpu-features.c
index 9d61cd56be..ba4df1d9e1 100644
--- a/sysdeps/x86/dl-get-cpu-features.c
+++ b/sysdeps/x86/dl-get-cpu-features.c
@@ -18,10 +18,17 @@
#include <ldsodefs.h>
-#undef __get_cpu_features
+#undef __x86_get_cpu_features
const struct cpu_features *
-__get_cpu_features (void)
+__x86_get_cpu_features (unsigned int max, int cpuid)
{
+ if (cpuid)
+ {
+ if (max > COMMON_CPUID_INDEX_MAX)
+ return NULL;
+ }
+ else if (max > USABLE_FEATURE_INDEX_MAX)
+ return NULL;
return &GLRO(dl_x86_cpu_features);
}
diff --git a/sysdeps/x86/include/cpu-features.h b/sysdeps/x86/include/cpu-features.h
new file mode 100644
index 0000000000..9424b4a924
--- /dev/null
+++ b/sysdeps/x86/include/cpu-features.h
@@ -0,0 +1,209 @@
+/* Data structure for x86 CPU features.
+ Copyright (C) 2020 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
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _PRIVATE_CPU_FEATURES_H
+#define _PRIVATE_CPU_FEATURES_H 1
+
+#ifdef _CPU_FEATURES_H
+# error this should be impossible
+#endif
+
+#ifndef _ISOMAC
+/* Get most of the contents from the public header, but we define a
+ different `struct cpu_features' type for private use. */
+# define cpu_features cpu_features_public
+# define __x86_get_cpu_features __x86_get_cpu_features_public
+#endif
+
+#include <sysdeps/x86/sys/platform/x86.h>
+
+#ifndef _ISOMAC
+
+# undef cpu_features
+# undef __x86_get_cpu_features
+# define __get_cpu_features() __x86_get_cpu_features (0, 0)
+
+enum
+{
+ /* The integer bit array index for the first set of preferred feature
+ bits. */
+ PREFERRED_FEATURE_INDEX_1 = 0,
+ /* The current maximum size of the feature integer bit array. */
+ PREFERRED_FEATURE_INDEX_MAX
+};
+
+# undef CPU_FEATURES_ARCH_P
+# define CPU_FEATURES_ARCH_P(ptr, name) \
+ ((ptr->feature_##name[index_arch_##name] & (bit_arch_##name)) != 0)
+
+/* HAS_CPU_FEATURE evaluates to true if CPU supports the feature. */
+# undef HAS_CPU_FEATURE
+# define HAS_CPU_FEATURE(name) \
+ CPU_FEATURES_CPU_P (__x86_get_cpu_features (0, 0), name)
+/* HAS_ARCH_FEATURE evaluates to true if we may use the feature at
+ runtime. */
+# define HAS_ARCH_FEATURE(name) \
+ CPU_FEATURES_ARCH_P (__x86_get_cpu_features (0, 0), name)
+/* CPU_FEATURE_USABLE evaluates to true if the feature is usable. */
+# undef CPU_FEATURE_USABLE
+# define CPU_FEATURE_USABLE(name) \
+ CPU_FEATURES_ARCH_P (__x86_get_cpu_features (0, 0), name##_Usable)
+
+/* USABLE_FEATURE_INDEX_1. */
+# define feature_AVX_Usable usable
+# define feature_AVX2_Usable usable
+# define feature_AVX512F_Usable usable
+# define feature_AVX512CD_Usable usable
+# define feature_AVX512ER_Usable usable
+# define feature_AVX512PF_Usable usable
+# define feature_AVX512VL_Usable usable
+# define feature_AVX512BW_Usable usable
+# define feature_AVX512DQ_Usable usable
+# define feature_AVX512_4FMAPS_Usable usable
+# define feature_AVX512_4VNNIW_Usable usable
+# define feature_AVX512_BITALG_Usable usable
+# define feature_AVX512_IFMA_Usable usable
+# define feature_AVX512_VBMI_Usable usable
+# define feature_AVX512_VBMI2_Usable usable
+# define feature_AVX512_VNNI_Usable usable
+# define feature_AVX512_VPOPCNTDQ_Usable usable
+# define feature_FMA_Usable usable
+# define feature_FMA4_Usable usable
+# define feature_VAES_Usable usable
+# define feature_VPCLMULQDQ_Usable usable
+# define feature_XOP_Usable usable
+# define feature_XSAVEC_Usable usable
+# define feature_F16C_Usable usable
+# define feature_AVX512_VP2INTERSECT_Usable usable
+# define feature_AVX512_BF16_Usable usable
+# define feature_PKU_Usable usable
+
+/* PREFERRED_FEATURE_INDEX_1. */
+# define bit_arch_I586 (1u << 0)
+# define bit_arch_I686 (1u << 1)
+# define bit_arch_Fast_Rep_String (1u << 2)
+# define bit_arch_Fast_Copy_Backward (1u << 3)
+# define bit_arch_Fast_Unaligned_Load (1u << 4)
+# define bit_arch_Fast_Unaligned_Copy (1u << 5)
+# define bit_arch_Slow_BSF (1u << 6)
+# define bit_arch_Slow_SSE4_2 (1u << 7)
+# define bit_arch_AVX_Fast_Unaligned_Load (1u << 8)
+# define bit_arch_Prefer_MAP_32BIT_EXEC (1u << 9)
+# define bit_arch_Prefer_PMINUB_for_stringop (1u << 10)
+# define bit_arch_Prefer_No_VZEROUPPER (1u << 11)
+# define bit_arch_Prefer_ERMS (1u << 12)
+# define bit_arch_Prefer_FSRM (1u << 13)
+# define bit_arch_Prefer_No_AVX512 (1u << 14)
+# define bit_arch_MathVec_Prefer_No_AVX512 (1u << 15)
+
+# define index_arch_Fast_Rep_String PREFERRED_FEATURE_INDEX_1
+# define index_arch_Fast_Copy_Backward PREFERRED_FEATURE_INDEX_1
+# define index_arch_Slow_BSF PREFERRED_FEATURE_INDEX_1
+# define index_arch_Fast_Unaligned_Load PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_PMINUB_for_stringop PREFERRED_FEATURE_INDEX_1
+# define index_arch_Fast_Unaligned_Copy PREFERRED_FEATURE_INDEX_1
+# define index_arch_I586 PREFERRED_FEATURE_INDEX_1
+# define index_arch_I686 PREFERRED_FEATURE_INDEX_1
+# define index_arch_Slow_SSE4_2 PREFERRED_FEATURE_INDEX_1
+# define index_arch_AVX_Fast_Unaligned_Load PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_MAP_32BIT_EXEC PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_No_VZEROUPPER PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_ERMS PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_No_AVX512 PREFERRED_FEATURE_INDEX_1
+# define index_arch_MathVec_Prefer_No_AVX512 PREFERRED_FEATURE_INDEX_1
+# define index_arch_Prefer_FSRM PREFERRED_FEATURE_INDEX_1
+
+# define feature_Fast_Rep_String preferred
+# define feature_Fast_Copy_Backward preferred
+# define feature_Slow_BSF preferred
+# define feature_Fast_Unaligned_Load preferred
+# define feature_Prefer_PMINUB_for_stringop preferred
+# define feature_Fast_Unaligned_Copy preferred
+# define feature_I586 preferred
+# define feature_I686 preferred
+# define feature_Slow_SSE4_2 preferred
+# define feature_AVX_Fast_Unaligned_Load preferred
+# define feature_Prefer_MAP_32BIT_EXEC preferred
+# define feature_Prefer_No_VZEROUPPER preferred
+# define feature_Prefer_ERMS preferred
+# define feature_Prefer_No_AVX512 preferred
+# define feature_MathVec_Prefer_No_AVX512 preferred
+# define feature_Prefer_FSRM preferred
+
+/* XCR0 Feature flags. */
+# define bit_XMM_state (1u << 1)
+# define bit_YMM_state (1u << 2)
+# define bit_Opmask_state (1u << 5)
+# define bit_ZMM0_15_state (1u << 6)
+# define bit_ZMM16_31_state (1u << 7)
+
+struct cpu_features
+{
+ struct cpu_features_basic basic;
+ unsigned int *usable_p;
+ struct cpuid_registers cpuid[COMMON_CPUID_INDEX_MAX];
+ unsigned int usable[USABLE_FEATURE_INDEX_MAX];
+ unsigned int preferred[PREFERRED_FEATURE_INDEX_MAX];
+ /* The state size for XSAVEC or XSAVE. The type must be unsigned long
+ int so that we use
+
+ sub xsave_state_size_offset(%rip) %RSP_LP
+
+ in _dl_runtime_resolve. */
+ unsigned long int xsave_state_size;
+ /* The full state size for XSAVE when XSAVEC is disabled by
+
+ GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVEC_Usable
+ */
+ unsigned int xsave_state_full_size;
+ /* Data cache size for use in memory and string routines, typically
+ L1 size. */
+ unsigned long int data_cache_size;
+ /* Shared cache size for use in memory and string routines, typically
+ L2 or L3 size. */
+ unsigned long int shared_cache_size;
+ /* Threshold to use non temporal store. */
+ unsigned long int non_temporal_threshold;
+};
+
+# if defined (_LIBC) && !IS_IN (nonlib)
+/* Unused for x86. */
+# define INIT_ARCH()
+# define __x86_get_cpu_features(max, cpuid) (&GLRO(dl_x86_cpu_features))
+# endif
+
+# ifdef __x86_64__
+# define HAS_CPUID 1
+# elif (defined __i586__ || defined __pentium__ \
+ || defined __geode__ || defined __k6__)
+# define HAS_CPUID 1
+# define HAS_I586 1
+# define HAS_I686 HAS_ARCH_FEATURE (I686)
+# elif defined __i486__
+# define HAS_CPUID 0
+# define HAS_I586 HAS_ARCH_FEATURE (I586)
+# define HAS_I686 HAS_ARCH_FEATURE (I686)
+# else
+# define HAS_CPUID 1
+# define HAS_I586 1
+# define HAS_I686 1
+# endif
+
+#endif /* !_ISOMAC */
+
+#endif /* include/cpu-features.h */
diff --git a/sysdeps/x86/cpu-features.h b/sysdeps/x86/sys/platform/x86.h
similarity index 77%
rename from sysdeps/x86/cpu-features.h
rename to sysdeps/x86/sys/platform/x86.h
index 574f055e0c..62718c3a8d 100644
--- a/sysdeps/x86/cpu-features.h
+++ b/sysdeps/x86/sys/platform/x86.h
@@ -1,4 +1,5 @@
-/* This file is part of the GNU C Library.
+/* Data structure for x86 CPU features.
+ This file is part of the GNU C Library.
Copyright (C) 2008-2020 Free Software Foundation, Inc.
The GNU C Library is free software; you can redistribute it and/or
@@ -15,8 +16,8 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#ifndef cpu_features_h
-#define cpu_features_h
+#ifndef _SYS_PLATFORM_X86_H
+#define _SYS_PLATFORM_X86_H
enum
{
@@ -27,15 +28,6 @@ enum
USABLE_FEATURE_INDEX_MAX
};
-enum
-{
- /* The integer bit array index for the first set of preferred feature
- bits. */
- PREFERRED_FEATURE_INDEX_1 = 0,
- /* The current maximum size of the feature integer bit array. */
- PREFERRED_FEATURE_INDEX_MAX
-};
-
enum
{
COMMON_CPUID_INDEX_1 = 0,
@@ -80,51 +72,30 @@ struct cpu_features
struct cpu_features_basic basic;
unsigned int *usable_p;
struct cpuid_registers cpuid[COMMON_CPUID_INDEX_MAX];
- unsigned int usable[USABLE_FEATURE_INDEX_MAX];
- unsigned int preferred[PREFERRED_FEATURE_INDEX_MAX];
- /* The state size for XSAVEC or XSAVE. The type must be unsigned long
- int so that we use
-
- sub xsave_state_size_offset(%rip) %RSP_LP
-
- in _dl_runtime_resolve. */
- unsigned long int xsave_state_size;
- /* The full state size for XSAVE when XSAVEC is disabled by
-
- GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVEC_Usable
- */
- unsigned int xsave_state_full_size;
- /* Data cache size for use in memory and string routines, typically
- L1 size. */
- unsigned long int data_cache_size;
- /* Shared cache size for use in memory and string routines, typically
- L2 or L3 size. */
- unsigned long int shared_cache_size;
- /* Threshold to use non temporal store. */
- unsigned long int non_temporal_threshold;
};
-/* Used from outside of glibc to get access to the CPU features
- structure. */
-extern const struct cpu_features *__get_cpu_features (void)
+/* Get a pointer to the CPU features structure. */
+extern const struct cpu_features *__x86_get_cpu_features (unsigned int,
+ int)
__attribute__ ((const));
-/* Only used directly in cpu-features.c. */
-# define CPU_FEATURES_CPU_P(ptr, name) \
+#define CPU_FEATURES_CPU_P(ptr, name) \
((ptr->cpuid[index_cpu_##name].reg_##name & (bit_cpu_##name)) != 0)
-# define CPU_FEATURES_ARCH_P(ptr, name) \
- ((ptr->feature_##name[index_arch_##name] & (bit_arch_##name)) != 0)
+#define CPU_FEATURES_ARCH_P(ptr, name) \
+ ((ptr->usable_p[index_arch_##name] & (bit_arch_##name)) != 0)
/* HAS_CPU_FEATURE evaluates to true if CPU supports the feature. */
-#define HAS_CPU_FEATURE(name) \
- CPU_FEATURES_CPU_P (__get_cpu_features (), name)
-/* HAS_ARCH_FEATURE evaluates to true if we may use the feature at
- runtime. */
-# define HAS_ARCH_FEATURE(name) \
- CPU_FEATURES_ARCH_P (__get_cpu_features (), name)
+#define HAS_CPU_FEATURE(name) \
+ (__extension__ \
+ ({ const struct cpu_features *__ptr = \
+ __x86_get_cpu_features (COMMON_CPUID_INDEX_MAX, 1); \
+ __ptr && CPU_FEATURES_CPU_P (__ptr, name); }))
/* CPU_FEATURE_USABLE evaluates to true if the feature is usable. */
-#define CPU_FEATURE_USABLE(name) \
- HAS_ARCH_FEATURE (name##_Usable)
+#define CPU_FEATURE_USABLE(name) \
+ (__extension__ \
+ ({ const struct cpu_features *__ptr = \
+ __x86_get_cpu_features (USABLE_FEATURE_INDEX_MAX, 0); \
+ __ptr && CPU_FEATURES_ARCH_P (__ptr, name##_Usable); }))
/* Architecture features. */
@@ -185,34 +156,6 @@ extern const struct cpu_features *__get_cpu_features (void)
#define index_arch_AVX512_BF16_Usable USABLE_FEATURE_INDEX_1
#define index_arch_PKU_Usable USABLE_FEATURE_INDEX_1
-#define feature_AVX_Usable usable
-#define feature_AVX2_Usable usable
-#define feature_AVX512F_Usable usable
-#define feature_AVX512CD_Usable usable
-#define feature_AVX512ER_Usable usable
-#define feature_AVX512PF_Usable usable
-#define feature_AVX512VL_Usable usable
-#define feature_AVX512BW_Usable usable
-#define feature_AVX512DQ_Usable usable
-#define feature_AVX512_4FMAPS_Usable usable
-#define feature_AVX512_4VNNIW_Usable usable
-#define feature_AVX512_BITALG_Usable usable
-#define feature_AVX512_IFMA_Usable usable
-#define feature_AVX512_VBMI_Usable usable
-#define feature_AVX512_VBMI2_Usable usable
-#define feature_AVX512_VNNI_Usable usable
-#define feature_AVX512_VPOPCNTDQ_Usable usable
-#define feature_FMA_Usable usable
-#define feature_FMA4_Usable usable
-#define feature_VAES_Usable usable
-#define feature_VPCLMULQDQ_Usable usable
-#define feature_XOP_Usable usable
-#define feature_XSAVEC_Usable usable
-#define feature_F16C_Usable usable
-#define feature_AVX512_VP2INTERSECT_Usable usable
-#define feature_AVX512_BF16_Usable usable
-#define feature_PKU_Usable usable
-
/* CPU features. */
/* COMMON_CPUID_INDEX_1. */
@@ -761,88 +704,4 @@ extern const struct cpu_features *__get_cpu_features (void)
/* EAX. */
#define reg_AVX512_BF16 eax
-/* FEATURE_INDEX_2. */
-#define bit_arch_I586 (1u << 0)
-#define bit_arch_I686 (1u << 1)
-#define bit_arch_Fast_Rep_String (1u << 2)
-#define bit_arch_Fast_Copy_Backward (1u << 3)
-#define bit_arch_Fast_Unaligned_Load (1u << 4)
-#define bit_arch_Fast_Unaligned_Copy (1u << 5)
-#define bit_arch_Slow_BSF (1u << 6)
-#define bit_arch_Slow_SSE4_2 (1u << 7)
-#define bit_arch_AVX_Fast_Unaligned_Load (1u << 8)
-#define bit_arch_Prefer_MAP_32BIT_EXEC (1u << 9)
-#define bit_arch_Prefer_PMINUB_for_stringop (1u << 10)
-#define bit_arch_Prefer_No_VZEROUPPER (1u << 11)
-#define bit_arch_Prefer_ERMS (1u << 12)
-#define bit_arch_Prefer_FSRM (1u << 13)
-#define bit_arch_Prefer_No_AVX512 (1u << 14)
-#define bit_arch_MathVec_Prefer_No_AVX512 (1u << 15)
-
-#define index_arch_Fast_Rep_String PREFERRED_FEATURE_INDEX_1
-#define index_arch_Fast_Copy_Backward PREFERRED_FEATURE_INDEX_1
-#define index_arch_Slow_BSF PREFERRED_FEATURE_INDEX_1
-#define index_arch_Fast_Unaligned_Load PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_PMINUB_for_stringop PREFERRED_FEATURE_INDEX_1
-#define index_arch_Fast_Unaligned_Copy PREFERRED_FEATURE_INDEX_1
-#define index_arch_I586 PREFERRED_FEATURE_INDEX_1
-#define index_arch_I686 PREFERRED_FEATURE_INDEX_1
-#define index_arch_Slow_SSE4_2 PREFERRED_FEATURE_INDEX_1
-#define index_arch_AVX_Fast_Unaligned_Load PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_MAP_32BIT_EXEC PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_No_VZEROUPPER PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_ERMS PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_No_AVX512 PREFERRED_FEATURE_INDEX_1
-#define index_arch_MathVec_Prefer_No_AVX512 PREFERRED_FEATURE_INDEX_1
-#define index_arch_Prefer_FSRM PREFERRED_FEATURE_INDEX_1
-
-#define feature_Fast_Rep_String preferred
-#define feature_Fast_Copy_Backward preferred
-#define feature_Slow_BSF preferred
-#define feature_Fast_Unaligned_Load preferred
-#define feature_Prefer_PMINUB_for_stringop preferred
-#define feature_Fast_Unaligned_Copy preferred
-#define feature_I586 preferred
-#define feature_I686 preferred
-#define feature_Slow_SSE4_2 preferred
-#define feature_AVX_Fast_Unaligned_Load preferred
-#define feature_Prefer_MAP_32BIT_EXEC preferred
-#define feature_Prefer_No_VZEROUPPER preferred
-#define feature_Prefer_ERMS preferred
-#define feature_Prefer_No_AVX512 preferred
-#define feature_MathVec_Prefer_No_AVX512 preferred
-#define feature_Prefer_FSRM preferred
-
-/* XCR0 Feature flags. */
-#define bit_XMM_state (1u << 1)
-#define bit_YMM_state (1u << 2)
-#define bit_Opmask_state (1u << 5)
-#define bit_ZMM0_15_state (1u << 6)
-#define bit_ZMM16_31_state (1u << 7)
-
-# if defined (_LIBC) && !IS_IN (nonlib)
-/* Unused for x86. */
-# define INIT_ARCH()
-# define __get_cpu_features() (&GLRO(dl_x86_cpu_features))
-# define x86_get_cpuid_registers(i) \
- (&(GLRO(dl_x86_cpu_features).cpuid[i]))
-# endif
-
-#ifdef __x86_64__
-# define HAS_CPUID 1
-#elif (defined __i586__ || defined __pentium__ \
- || defined __geode__ || defined __k6__)
-# define HAS_CPUID 1
-# define HAS_I586 1
-# define HAS_I686 HAS_ARCH_FEATURE (I686)
-#elif defined __i486__
-# define HAS_CPUID 0
-# define HAS_I586 HAS_ARCH_FEATURE (I586)
-# define HAS_I686 HAS_ARCH_FEATURE (I686)
-#else
-# define HAS_CPUID 1
-# define HAS_I586 1
-# define HAS_I686 1
-#endif
-
-#endif /* cpu_features_h */
+#endif /* _SYS_PLATFORM_X86_H */
diff --git a/sysdeps/x86/tst-get-cpu-features.c b/sysdeps/x86/tst-get-cpu-features.c
index c60918cf00..60a18fed33 100644
--- a/sysdeps/x86/tst-get-cpu-features.c
+++ b/sysdeps/x86/tst-get-cpu-features.c
@@ -1,4 +1,4 @@
-/* Test case for x86 __get_cpu_features interface
+/* Test case for __x86_get_cpu_features interface
Copyright (C) 2015-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
@@ -18,7 +18,7 @@
#include <stdlib.h>
#include <stdio.h>
-#include <cpu-features.h>
+#include <sys/platform/x86.h>
#include <support/check.h>
#define CHECK_CPU_FEATURE(name) \
@@ -45,7 +45,7 @@ static const char * const cpu_kinds[] =
static int
do_test (void)
{
- const struct cpu_features *cpu_features = __get_cpu_features ();
+ const struct cpu_features *cpu_features = __x86_get_cpu_features (0, 0);
switch (cpu_features->basic.kind)
{
diff --git a/sysdeps/x86_64/fpu/math-tests-arch.h b/sysdeps/x86_64/fpu/math-tests-arch.h
index 435ddad991..cc3c2b0c11 100644
--- a/sysdeps/x86_64/fpu/math-tests-arch.h
+++ b/sysdeps/x86_64/fpu/math-tests-arch.h
@@ -16,7 +16,7 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <cpu-features.h>
+#include <sys/platform/x86.h>
#if defined REQUIRE_AVX
@@ -24,7 +24,7 @@
# define CHECK_ARCH_EXT \
do \
{ \
- if (!HAS_ARCH_FEATURE (AVX_Usable)) return; \
+ if (!CPU_FEATURE_USABLE (AVX)) return; \
} \
while (0)
@@ -34,7 +34,7 @@
# define CHECK_ARCH_EXT \
do \
{ \
- if (!HAS_ARCH_FEATURE (AVX2_Usable)) return; \
+ if (!CPU_FEATURE_USABLE (AVX2)) return; \
} \
while (0)
@@ -44,7 +44,7 @@
# define CHECK_ARCH_EXT \
do \
{ \
- if (!HAS_ARCH_FEATURE (AVX512F_Usable)) return; \
+ if (!CPU_FEATURE_USABLE (AVX512F)) return; \
} \
while (0)
diff --git a/sysdeps/x86_64/multiarch/test-multiarch.c b/sysdeps/x86_64/multiarch/test-multiarch.c
index 317373ceda..9feaf057e5 100644
--- a/sysdeps/x86_64/multiarch/test-multiarch.c
+++ b/sysdeps/x86_64/multiarch/test-multiarch.c
@@ -16,7 +16,7 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <cpu-features.h>
+#include <sys/platform/x86.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -75,10 +75,10 @@ do_test (int argc, char **argv)
int fails;
get_cpuinfo ();
- fails = check_proc ("avx", HAS_ARCH_FEATURE (AVX_Usable),
- "HAS_ARCH_FEATURE (AVX_Usable)");
- fails += check_proc ("fma4", HAS_ARCH_FEATURE (FMA4_Usable),
- "HAS_ARCH_FEATURE (FMA4_Usable)");
+ fails = check_proc ("avx", CPU_FEATURE_USABLE (AVX),
+ "CPU_FEATURE_USABLE (AVX)");
+ fails += check_proc ("fma4", CPU_FEATURE_USABLE (FMA4),
+ "CPU_FEATURE_USABLE (FMA4)");
fails += check_proc ("sse4_2", HAS_CPU_FEATURE (SSE4_2),
"HAS_CPU_FEATURE (SSE4_2)");
fails += check_proc ("sse4_1", HAS_CPU_FEATURE (SSE4_1)
--
2.26.2
More information about the Libc-alpha
mailing list