x86: Set dl_platform and dl_hwcap from CPU features [BZ #21391]

dl_platform and dl_hwcap are set from AT_PLATFORM and AT_HWCAP very
early during startup.  They are used by dynamic linker to determine
platform and build an array of hardware capability names, which are
added to search path when loading shared object.  dl_platform and
dl_hwcap are unused on x86-64.  On i386, i386, i486, i586 and i686
platforms were supported and only SSE2 capability was used.

On x86, usage of AT_PLATFORM and AT_HWCAP to determine platform and
processor capabilities is obsolete since all information is available
in dl_x86_cpu_features.  This patch sets dl_platform and dl_hwcap from
dl_x86_cpu_features in dynamic linker.  On i386, the available plaforms
are changed to i586 and i686 since i386 has been deprecated.  On x86-64,
the available plaforms are haswell, which is for Haswell class processors
with BMI1, BMI2, LZCNT, MOVBE, POPCNT, AVX2 and FMA, and xeon_phi, which
is for Xeon Phi class processors with AVX512F, AVX512CD, AVX512ER and
AVX512PF.  A capability, avx512_1, is also added to x86-64 for AVX512
ISAs: AVX512F, AVX512CD, AVX512BW, AVX512DQ and AVX512VL.

	[BZ #21391]
	* sysdeps/i386/dl-machine.h (dl_platform_init) [IS_IN (rtld)]:
	Only call init_cpu_features.
	[!IS_IN (rtld)]: Only set GLRO(dl_platform) to NULL if needed.
	* sysdeps/x86_64/dl-machine.h (dl_platform_init): Likewise.
	* sysdeps/i386/dl-procinfo.h: Removed.
	* sysdeps/unix/sysv/linux/i386/dl-procinfo.h: Don't include
	<sysdeps/i386/dl-procinfo.h> nor <ldsodefs.h>.  Include
	<sysdeps/x86/dl-procinfo.h>.
	(_dl_procinfo): Replace _DL_HWCAP_COUNT with 32.
	* sysdeps/unix/sysv/linux/x86_64/dl-procinfo.h [!IS_IN (ldconfig)]:
	Include <sysdeps/x86/dl-procinfo.h> instead of
	 <sysdeps/generic/dl-procinfo.h>.
	* sysdeps/x86/cpu-features.c: Include <dl-hwcap.h>.
	(init_cpu_features): Set dl_platform, dl_hwcap and dl_hwcap_mask.
	* sysdeps/x86/cpu-features.h (bit_cpu_LZCNT): New.
	(bit_cpu_MOVBE): Likewise.
	(bit_cpu_BMI1): Likewise.
	(bit_cpu_BMI2): Likewise.
	(index_cpu_BMI1): Likewise.
	(index_cpu_BMI2): Likewise.
	(index_cpu_LZCNT): Likewise.
	(index_cpu_MOVBE): Likewise.
	(index_cpu_POPCNT): Likewise.
	(reg_BMI1): Likewise.
	(reg_BMI2): Likewise.
	(reg_LZCNT): Likewise.
	(reg_MOVBE): Likewise.
	(reg_POPCNT): Likewise.
	* sysdeps/x86/dl-hwcap.h: New file.
	* sysdeps/x86/dl-procinfo.h: Likewise.
	* sysdeps/x86/dl-procinfo.c (_dl_x86_hwcap_flags): New.
	(_dl_x86_platforms): Likewise.

3 files changed, 6 insertions, 127 deletions

diff --git a/sysdeps/i386/dl-machine.h b/sysdeps/i386/dl-machine.h
index 99a72f68f4..57d4a0bdbd 100644
--- a/sysdeps/i386/dl-machine.h
+++ b/sysdeps/i386/dl-machine.h
@@ -233,14 +233,14 @@ _dl_start_user:\n\
 static inline void __attribute__ ((unused))
 dl_platform_init (void)
 {
-  if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0')
-    /* Avoid an empty string which would disturb us.  */
-    GLRO(dl_platform) = NULL;
-
-#ifdef SHARED
+#if IS_IN (rtld)
   /* init_cpu_features has been called early from __libc_start_main in
      static executable.  */
   init_cpu_features (&GLRO(dl_x86_cpu_features));
+#else
+  if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0')
+    /* Avoid an empty string which would disturb us.  */
+    GLRO(dl_platform) = NULL;
 #endif
 }
 
diff --git a/sysdeps/i386/dl-procinfo.c b/sysdeps/i386/dl-procinfo.c
index b83283004e..7237f778b2 100644
--- a/sysdeps/i386/dl-procinfo.c
+++ b/sysdeps/i386/dl-procinfo.c
@@ -17,10 +17,7 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-/* This information must be kept in sync with the _DL_HWCAP_COUNT and
-   _DL_PLATFORM_COUNT definitions in procinfo.h.
-
-   If anything should be added here check whether the size of each string
+/* If anything should be added here check whether the size of each string
    is still ok with the given array size.
 
    All the #ifdefs in the definitions are quite irritating but
@@ -64,21 +61,5 @@ PROCINFO_CLASS const char _dl_x86_cap_flags[32][8]
 ,
 #endif
 
-#if !defined PROCINFO_DECL && defined SHARED
-  ._dl_x86_platforms
-#else
-PROCINFO_CLASS const char _dl_x86_platforms[4][5]
-#endif
-#ifndef PROCINFO_DECL
-= {
-    "i386", "i486", "i586", "i686"
-  }
-#endif
-#if !defined SHARED || defined PROCINFO_DECL
-;
-#else
-,
-#endif
-
 #undef PROCINFO_DECL
 #undef PROCINFO_CLASS
diff --git a/sysdeps/i386/dl-procinfo.h b/sysdeps/i386/dl-procinfo.h
deleted file mode 100644
index 9c38846f0b..0000000000
--- a/sysdeps/i386/dl-procinfo.h
+++ /dev/null
@@ -1,102 +0,0 @@
-/* i386 version of processor capability information handling macros.
-   Copyright (C) 1998-2017 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
-
-   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 _DL_PROCINFO_H
-#define _DL_PROCINFO_H	1
-#include <ldsodefs.h>
-
-#define _DL_HWCAP_COUNT 32
-
-#define _DL_PLATFORMS_COUNT	4
-
-/* Start at 48 to reserve some space.  */
-#define _DL_FIRST_PLATFORM	48
-/* Mask to filter out platforms.  */
-#define _DL_HWCAP_PLATFORM	(((1ULL << _DL_PLATFORMS_COUNT) - 1) \
-				 << _DL_FIRST_PLATFORM)
-
-enum
-{
-  HWCAP_I386_FPU   = 1 << 0,
-  HWCAP_I386_VME   = 1 << 1,
-  HWCAP_I386_DE    = 1 << 2,
-  HWCAP_I386_PSE   = 1 << 3,
-  HWCAP_I386_TSC   = 1 << 4,
-  HWCAP_I386_MSR   = 1 << 5,
-  HWCAP_I386_PAE   = 1 << 6,
-  HWCAP_I386_MCE   = 1 << 7,
-  HWCAP_I386_CX8   = 1 << 8,
-  HWCAP_I386_APIC  = 1 << 9,
-  HWCAP_I386_SEP   = 1 << 11,
-  HWCAP_I386_MTRR  = 1 << 12,
-  HWCAP_I386_PGE   = 1 << 13,
-  HWCAP_I386_MCA   = 1 << 14,
-  HWCAP_I386_CMOV  = 1 << 15,
-  HWCAP_I386_FCMOV = 1 << 16,
-  HWCAP_I386_MMX   = 1 << 23,
-  HWCAP_I386_OSFXSR = 1 << 24,
-  HWCAP_I386_XMM   = 1 << 25,
-  HWCAP_I386_XMM2  = 1 << 26,
-  HWCAP_I386_AMD3D = 1 << 31,
-
-  /* XXX Which others to add here?  */
-  HWCAP_IMPORTANT = (HWCAP_I386_XMM2)
-
-};
-
-/* We cannot provide a general printing function.  */
-#define _dl_procinfo(type, word) -1
-
-static inline const char *
-__attribute__ ((unused))
-_dl_hwcap_string (int idx)
-{
-  return GLRO(dl_x86_cap_flags)[idx];
-};
-
-static inline int
-__attribute__ ((unused, always_inline))
-_dl_string_hwcap (const char *str)
-{
-  int i;
-
-  for (i = 0; i < _DL_HWCAP_COUNT; i++)
-    {
-      if (strcmp (str, GLRO(dl_x86_cap_flags)[i]) == 0)
-	return i;
-    }
-  return -1;
-};
-
-static inline int
-__attribute__ ((unused, always_inline))
-_dl_string_platform (const char *str)
-{
-  int i;
-
-  if (str != NULL)
-    for (i = 0; i < _DL_PLATFORMS_COUNT; ++i)
-      {
-	if (strcmp (str, GLRO(dl_x86_platforms)[i]) == 0)
-	  return _DL_FIRST_PLATFORM + i;
-      }
-  return -1;
-};
-
-#endif /* dl-procinfo.h */