detect cpu feature for all x64 and x86 platforms (no longer windows only).

detect cpu feature for all x64 and x86 platforms (no longer windows only).


BUG=None
TEST=trybot

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=75150

[jiesun, 2011-02-15 00:44:49]

please help to review.

[fbarchard, 2011-02-15 01:42:56]

http://codereview.chromium.org/6526005/diff/3001/base/cpu.cc
File base/cpu.cc (right):

http://codereview.chromium.org/6526005/diff/3001/base/cpu.cc#newcode1
base/cpu.cc:1: // Copyright (c) 2006-2008 The Chromium Authors. All rights
reserved.
(C) 2011

http://codereview.chromium.org/6526005/diff/3001/base/cpu.cc#newcode42
base/cpu.cc:42: #endif
Your ebx usage seems -m32 -fpic unsafe?
I tried it, and it segfaulted
fbarchard@muni:~/icpuid$ g++ -fomit-frame-pointer -O3 -fpic -m32 -DGAS_ASM
-DCPU_DEBUG icpuid.cpp -o icpuid
fbarchard@muni:~/icpuid$ ./icpuid
Segmentation fault
fbarchard@muni:~/icpuid$ g++ -fomit-frame-pointer -O3 -m32 -DGAS_ASM -DCPU_DEBUG
icpuid.cpp -o icpuid
fbarchard@muni:~/icpuid$ ./icpuid
Brand: GenuineIntel
Cores: 4
ExtendedFamilyID 00000000
ExtendedModel 00000001
FamilyID 00000006
Model 00000007
SteppingID 0000000a
Hyperthreading 1
CPU has Intel "Core" Processor
fbarchard@muni:~/icpuid$ g++ -fomit-frame-pointer -O3 -m64 -DGAS_ASM -DCPU_DEBUG
icpuid.cpp -o icpuid
fbarchard@muni:~/icpuid$ ./icpuid
Brand: GenuineIntel
Cores: 1
ExtendedFamilyID 00000000
ExtendedModel 00000001
FamilyID 00000006
Model 00000007
SteppingID 0000000a
Hyperthreading 1
CPU has Intel "Core" Processor
fbarchard@muni:~/icpuid$ g++ -fomit-frame-pointer -O3 -fpic -m64 -DGAS_ASM
-DCPU_DEBUG icpuid.cpp -o icpuid
fbarchard@muni:~/icpuid$ ./icpuid
Segmentation fault

I have not found a clean way to do it either, though.
#if defined(__pic__) && defined(__i386__)
void my__cpuidex(int cpu_info[4], int InfoType, int InfoIndex) {
  int dummyeax, dummyecx;
  __asm__ volatile (
    "\n\t    pushl   %%ebx"
    "\n\t    cpuid"
    "\n\t    movl    %%eax, 0(%[cpu_info])"
    "\n\t    movl    %%ebx, 4(%[cpu_info])"
    "\n\t    movl    %%ecx, 8(%[cpu_info])"
    "\n\t    movl    %%edx, 12(%[cpu_info])"
    "\n\t    pop     %%ebx"
    : "=a" (dummyeax), "=c" (dummyecx)  // out
    : [cpu_info]"D" (&cpu_info[0]), "0" (InfoType), "1" (InfoIndex) // in
    : "memory", "%edx"  // modified
  );
}
#else
void my__cpuidex(int cpu_info[4], int InfoType, int InfoIndex) {
  int dummyeax, dummyecx;
  __asm__ volatile (
    "\n\t    cpuid"
    "\n\t    movl    %%eax, 0(%[cpu_info])"
    "\n\t    movl    %%ebx, 4(%[cpu_info])"
    "\n\t    movl    %%ecx, 8(%[cpu_info])"
    "\n\t    movl    %%edx, 12(%[cpu_info])"
    : "=a" (dummyeax), "=c" (dummyecx)  // out
    : [cpu_info]"D" (&cpu_info[0]), "0" (InfoType), "1" (InfoIndex) // in
    : "memory", "%ebx", "%edx"  // modified
  );
}
#endif

http://codereview.chromium.org/6526005/diff/3001/base/cpu.cc#newcode74
base/cpu.cc:74: has_sse2_ = (cpu_info[3] & (1<<26)) != 0;
add has_ssse3_ while you're at it?  Or a todo

[jiesun, 2011-02-15 21:12:11]

thanks for review. please have another look.

[fbarchard, 2011-02-15 21:30:11]

LGTM w/ nits
in future you might want to support arm
in future you may want to add more of the features from talk, which I'll
integrate into libjingle:
http://s/?fileprint=//depot/googleclient/talk/base/systeminfo.cc

http://codereview.chromium.org/6526005/diff/6002/base/cpu.cc
File base/cpu.cc (right):

http://codereview.chromium.org/6526005/diff/6002/base/cpu.cc#newcode1
base/cpu.cc:1: // Copyright (c) 2006-2008 The Chromium Authors. All rights
reserved.
(c) 2011

http://codereview.chromium.org/6526005/diff/6002/base/cpu.cc#newcode36
base/cpu.cc:36: __cpuid(info_type, info[0], info[1], info[2], info[3]);
perfect :)

http://codereview.chromium.org/6526005/diff/6002/base/cpu.h
File base/cpu.h (right):

http://codereview.chromium.org/6526005/diff/6002/base/cpu.h#newcode1
base/cpu.h:1: // Copyright (c) 2006-2008 The Chromium Authors. All rights
reserved.
(c) 2011

[fbarchard, 2011-02-15 21:41:56]

hmmm.  cpuid.h exists on my lucid box.  You may need to do your own macro?
base/cpu.cc:11:19: error: cpuid.h: No such file or directory

[fbarchard, 2011-02-15 22:29:33]

On 2011/02/15 21:41:56, fbarchard wrote:
> hmmm.  cpuid.h exists on my lucid box.  You may need to do your own macro?
> base/cpu.cc:11:19: error: cpuid.h: No such file or directory

The location of the header is here on linux
/usr/lib/gcc/x86_64-linux-gnu/4.4/include/cpuid.h

here on msys
C:\MinGW\lib\gcc\mingw32\4.5.0\include\cpuid.h

but its missing on Mac, which should have it here if anywhere
/usr/lib/gcc/i686-apple-darwin10/4.2.1/include

So the following could be used:

#ifndef _MSC_VER

#if defined(__pic__) && defined(__i386__)

void __cpuidex(int cpu_info[4], int info_type, int info_index) {
  __asm__ volatile (
    "mov %%ebx, %%edi\n"
    "cpuid\n"
    "xchg %%edi, %%ebx\n"
    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
    : "a"(info_type), "c"(info_index)
  );
}
void __cpuid(int cpu_info[4], int info_type) {
  __asm__ volatile (
    "mov %%ebx, %%edi\n"
    "cpuid\n"
    "xchg %%edi, %%ebx\n"
    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
    : "a"(info_type)
  );
}

#else

void __cpuidex(int cpu_info[4], int info_type, int info_index) {
  __asm__ volatile (
    "cpuid \n\t"
    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
    : "a"(info_type), "c"(info_index)
  );
}

void __cpuid(int cpu_info[4], int info_type) {
  __asm__ volatile (
    "cpuid \n\t"
    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
    : "a"(info_type)
  );
}

#endif
#endif

[fbarchard, 2011-02-16 00:30:15]

http://codereview.chromium.org/6526005/diff/2005/base/cpu.cc
File base/cpu.cc (right):

http://codereview.chromium.org/6526005/diff/2005/base/cpu.cc#newcode116
base/cpu.cc:116: has_sse4_ = (cpu_info[2] & 0x00080000) != 0;
I think you mean sse41 ?  should probably be explicit.

[fbarchard, 2011-02-16 00:44:39]

LGTM