cpuid.h

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/*
 * Copyright (C) 2007-2013 Free Software Foundation, Inc.
 *
 * This file is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 3, or (at your option) any
 * later version.
 * 
 * This file 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
 * General Public License for more details.
 * 
 * Under Section 7 of GPL version 3, you are granted additional
 * permissions described in the GCC Runtime Library Exception, version
 * 3.1, as published by the Free Software Foundation.
 * 
 * You should have received a copy of the GNU General Public License and
 * a copy of the GCC Runtime Library Exception along with this program;
 * see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 * <http://www.gnu.org/licenses/>.
 */

/* %ecx */
#define bit_SSE3    (1 << 0)
#define bit_PCLMUL  (1 << 1)
#define bit_LZCNT   (1 << 5)
#define bit_SSSE3   (1 << 9)
#define bit_FMA     (1 << 12)
#define bit_CMPXCHG16B  (1 << 13)
#define bit_SSE4_1  (1 << 19)
#define bit_SSE4_2  (1 << 20)
#define bit_MOVBE   (1 << 22)
#define bit_POPCNT  (1 << 23)
#define bit_AES     (1 << 25)
#define bit_XSAVE   (1 << 26)
#define bit_OSXSAVE (1 << 27)
#define bit_AVX     (1 << 28)
#define bit_F16C    (1 << 29)
#define bit_RDRND   (1 << 30)

/* %edx */
#define bit_CMPXCHG8B   (1 << 8)
#define bit_CMOV    (1 << 15)
#define bit_MMX     (1 << 23)
#define bit_FXSAVE  (1 << 24)
#define bit_SSE     (1 << 25)
#define bit_SSE2    (1 << 26)

/* Extended Features */
/* %ecx */
#define bit_LAHF_LM (1 << 0)
#define bit_ABM     (1 << 5)
#define bit_SSE4a   (1 << 6)
#define bit_PRFCHW  (1 << 8)
#define bit_XOP         (1 << 11)
#define bit_LWP     (1 << 15)
#define bit_FMA4        (1 << 16)
#define bit_TBM         (1 << 21)

/* %edx */
#define bit_MMXEXT  (1 << 22)
#define bit_LM      (1 << 29)
#define bit_3DNOWP  (1 << 30)
#define bit_3DNOW   (1 << 31)

/* Extended Features (%eax == 7) */
#define bit_FSGSBASE    (1 << 0)
#define bit_BMI (1 << 3)
#define bit_HLE (1 << 4)
#define bit_AVX2    (1 << 5)
#define bit_BMI2    (1 << 8)
#define bit_RTM (1 << 11)
#define bit_RDSEED  (1 << 18)
#define bit_ADX (1 << 19)

/* Extended State Enumeration Sub-leaf (%eax == 13, %ecx == 1) */
#define bit_XSAVEOPT    (1 << 0)

/* Signatures for different CPU implementations as returned in uses
   of cpuid with level 0.  */
#define signature_AMD_ebx   0x68747541
#define signature_AMD_ecx   0x444d4163
#define signature_AMD_edx   0x69746e65

#define signature_CENTAUR_ebx   0x746e6543
#define signature_CENTAUR_ecx   0x736c7561
#define signature_CENTAUR_edx   0x48727561

#define signature_CYRIX_ebx 0x69727943
#define signature_CYRIX_ecx 0x64616574
#define signature_CYRIX_edx 0x736e4978

#define signature_INTEL_ebx 0x756e6547
#define signature_INTEL_ecx 0x6c65746e
#define signature_INTEL_edx 0x49656e69

#define signature_TM1_ebx   0x6e617254
#define signature_TM1_ecx   0x55504361
#define signature_TM1_edx   0x74656d73

#define signature_TM2_ebx   0x756e6547
#define signature_TM2_ecx   0x3638784d
#define signature_TM2_edx   0x54656e69

#define signature_NSC_ebx   0x646f6547
#define signature_NSC_ecx   0x43534e20
#define signature_NSC_edx   0x79622065

#define signature_NEXGEN_ebx    0x4778654e
#define signature_NEXGEN_ecx    0x6e657669
#define signature_NEXGEN_edx    0x72446e65

#define signature_RISE_ebx  0x65736952
#define signature_RISE_ecx  0x65736952
#define signature_RISE_edx  0x65736952

#define signature_SIS_ebx   0x20536953
#define signature_SIS_ecx   0x20536953
#define signature_SIS_edx   0x20536953

#define signature_UMC_ebx   0x20434d55
#define signature_UMC_ecx   0x20434d55
#define signature_UMC_edx   0x20434d55

#define signature_VIA_ebx   0x20414956
#define signature_VIA_ecx   0x20414956
#define signature_VIA_edx   0x20414956

#define signature_VORTEX_ebx    0x74726f56
#define signature_VORTEX_ecx    0x436f5320
#define signature_VORTEX_edx    0x36387865

#if defined(__i386__) && defined(__PIC__)
/* %ebx may be the PIC register.  */
#if __GNUC__ >= 3
#define __cpuid(level, a, b, c, d)          \
  __asm__ ("xchg{l}\t{%%}ebx, %k1\n\t"          \
       "cpuid\n\t"                  \
       "xchg{l}\t{%%}ebx, %k1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level))

#define __cpuid_count(level, count, a, b, c, d)     \
  __asm__ ("xchg{l}\t{%%}ebx, %k1\n\t"          \
       "cpuid\n\t"                  \
       "xchg{l}\t{%%}ebx, %k1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level), "2" (count))
#else
/* Host GCCs older than 3.0 weren't supporting Intel asm syntax
   nor alternatives in i386 code.  */
#define __cpuid(level, a, b, c, d)          \
  __asm__ ("xchgl\t%%ebx, %k1\n\t"          \
       "cpuid\n\t"                  \
       "xchgl\t%%ebx, %k1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level))

#define __cpuid_count(level, count, a, b, c, d)     \
  __asm__ ("xchgl\t%%ebx, %k1\n\t"          \
       "cpuid\n\t"                  \
       "xchgl\t%%ebx, %k1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level), "2" (count))
#endif
#elif defined(__x86_64__) && (defined(__code_model_medium__) || defined(__code_model_large__)) && defined(__PIC__)
/* %rbx may be the PIC register.  */
#define __cpuid(level, a, b, c, d)          \
  __asm__ ("xchg{q}\t{%%}rbx, %q1\n\t"          \
       "cpuid\n\t"                  \
       "xchg{q}\t{%%}rbx, %q1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level))

#define __cpuid_count(level, count, a, b, c, d)     \
  __asm__ ("xchg{q}\t{%%}rbx, %q1\n\t"          \
       "cpuid\n\t"                  \
       "xchg{q}\t{%%}rbx, %q1\n\t"          \
       : "=a" (a), "=&r" (b), "=c" (c), "=d" (d)    \
       : "0" (level), "2" (count))
#else
#define __cpuid(level, a, b, c, d)          \
  __asm__ ("cpuid\n\t"                  \
       : "=a" (a), "=b" (b), "=c" (c), "=d" (d) \
       : "0" (level))

#define __cpuid_count(level, count, a, b, c, d)     \
  __asm__ ("cpuid\n\t"                  \
       : "=a" (a), "=b" (b), "=c" (c), "=d" (d) \
       : "0" (level), "2" (count))
#endif

/* Return highest supported input value for cpuid instruction.  ext can
   be either 0x0 or 0x8000000 to return highest supported value for
   basic or extended cpuid information.  Function returns 0 if cpuid
   is not supported or whatever cpuid returns in eax register.  If sig
   pointer is non-null, then first four bytes of the signature
   (as found in ebx register) are returned in location pointed by sig.  */

static __inline unsigned int
__get_cpuid_max (unsigned int __ext, unsigned int *__sig)
{
  unsigned int __eax, __ebx, __ecx, __edx;

#ifndef __x86_64__
  /* See if we can use cpuid.  On AMD64 we always can.  */
#if __GNUC__ >= 3
  __asm__ ("pushf{l|d}\n\t"
       "pushf{l|d}\n\t"
       "pop{l}\t%0\n\t"
       "mov{l}\t{%0, %1|%1, %0}\n\t"
       "xor{l}\t{%2, %0|%0, %2}\n\t"
       "push{l}\t%0\n\t"
       "popf{l|d}\n\t"
       "pushf{l|d}\n\t"
       "pop{l}\t%0\n\t"
       "popf{l|d}\n\t"
       : "=&r" (__eax), "=&r" (__ebx)
       : "i" (0x00200000));
#else
/* Host GCCs older than 3.0 weren't supporting Intel asm syntax
   nor alternatives in i386 code.  */
  __asm__ ("pushfl\n\t"
       "pushfl\n\t"
       "popl\t%0\n\t"
       "movl\t%0, %1\n\t"
       "xorl\t%2, %0\n\t"
       "pushl\t%0\n\t"
       "popfl\n\t"
       "pushfl\n\t"
       "popl\t%0\n\t"
       "popfl\n\t"
       : "=&r" (__eax), "=&r" (__ebx)
       : "i" (0x00200000));
#endif

  if (!((__eax ^ __ebx) & 0x00200000))
    return 0;
#endif

  /* Host supports cpuid.  Return highest supported cpuid input value.  */
  __cpuid (__ext, __eax, __ebx, __ecx, __edx);

  if (__sig)
    *__sig = __ebx;

  return __eax;
}

/* Return cpuid data for requested cpuid level, as found in returned
   eax, ebx, ecx and edx registers.  The function checks if cpuid is
   supported and returns 1 for valid cpuid information or 0 for
   unsupported cpuid level.  All pointers are required to be non-null.  */

static __inline int
__get_cpuid (unsigned int __level,
         unsigned int *__eax, unsigned int *__ebx,
         unsigned int *__ecx, unsigned int *__edx)
{
  unsigned int __ext = __level & 0x80000000;

  if (__get_cpuid_max (__ext, 0) < __level)
    return 0;

  __cpuid (__level, *__eax, *__ebx, *__ecx, *__edx);
  return 1;
}