[x64] Introduce FMA3 instructions on scalar data elements.

[x64] Introduce FMA3 instructions on scalar data elements.

R=bmeurer@chromium.org

Committed: https://chromium.googlesource.com/v8/v8/+/83a635e0d70f144300ea83be0d7effc1eb1bf6ef

[Weiliang, 2014-11-24 13:19:44]

Patchset #3 (id:40001) has been deleted

[Weiliang, 2014-11-24 13:44:54]

Patchset #3 (id:60001) has been deleted

[Weiliang, 2014-11-24 14:11:10]

Patchset #3 (id:80001) has been deleted

[Weiliang, 2014-11-24 14:12:26]

Patchset #3 (id:100001) has been deleted

[Weiliang, 2014-11-25 14:41:27]

weiliang.lin@intel.com changed reviewers:
+ bmeurer@chromium.org, danno@chromium.org, dcarney@chromium.org,
titzer@chromium.org

[Weiliang, 2014-11-25 14:41:27]

PTAL

[Benedikt Meurer, 2014-11-25 17:32:42]

We only need AVX 128bit support for now, so we don't really care whether the
operating supports AVX 256bit or not. Please remove that AVX OS support
detection for now.

https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc
File src/base/cpu.cc (right):

https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc#newcode67
src/base/cpu.cc:67: static V8_INLINE bool avx_os_support() {
That does not belong here. The CPU class should only be concerned with detecting
AVX support in the CPU. Also I don't think that we actually care about the AVX
OS support unless we make use of the ymm registers. We should really separate
that, and move the AVX OS detection to platform.h.

https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc#newcode375
src/base/cpu.cc:375: has_avx_ = ((cpu_info[2] & 0x18000000) == 0x18000000) &&
avx_os_support();
As mentioned above, remove the avx_os_support here.

[Weiliang, 2014-11-26 03:43:36]

On 2014/11/25 17:32:42, Benedikt Meurer wrote:
> We only need AVX 128bit support for now, so we don't really care whether the
> operating supports AVX 256bit or not. Please remove that AVX OS support
> detection for now.
> 
> https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc
> File src/base/cpu.cc (right):
> 
>
https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc#newcode67
> src/base/cpu.cc:67: static V8_INLINE bool avx_os_support() {
> That does not belong here. The CPU class should only be concerned with
detecting
> AVX support in the CPU. Also I don't think that we actually care about the AVX
> OS support unless we make use of the ymm registers. We should really separate
> that, and move the AVX OS detection to platform.h.
> 
>
https://codereview.chromium.org/757503002/diff/120001/src/base/cpu.cc#newcode375
> src/base/cpu.cc:375: has_avx_ = ((cpu_info[2] & 0x18000000) == 0x18000000) &&
> avx_os_support();
> As mentioned above, remove the avx_os_support here.

Thanks, I removed the avx_os_support and will add it on demand. 

Thanks
-Weiliang

[Benedikt Meurer, 2014-11-26 05:14:43]

Thanks, LGTM.

Can you port those changes to ia32 as well?

[Benedikt Meurer, 2014-11-26 05:32:01]

Committed patchset #4 (id:140001) manually as
83a635e0d70f144300ea83be0d7effc1eb1bf6ef (presubmit successful).