[x64] Introduce BMI instructions.

[x64] Introduce BMI instructions.

BUG=v8:4015
LOG=n

Committed: https://crrev.com/584a351484b7423605b282386225f26622262d8d
Cr-Commit-Position: refs/heads/master@{#27648}

[Jing, 2015-04-03 02:58:42]

jing.bao@intel.com changed reviewers:
+ bmeurer@google.com, danno@chromium.org, weiliang.lin@intel.com

[Weiliang, 2015-04-03 03:01:26]

On 2015/04/03 02:58:43, Jing wrote:

LGTM, but still need Benedikt and danno's

[Weiliang, 2015-04-08 03:25:19]

weiliang.lin@intel.com changed reviewers:
+ bmeurer@chromium.org
- bmeurer@google.com

[Weiliang, 2015-04-08 03:25:20]

Ping~

[Benedikt Meurer, 2015-04-08 04:36:21]

Looking good with nit. Can you also fix the two TODO(intel) in
macro-assembler-x64.cc (MacroAssembler::Lzcntl)?

https://codereview.chromium.org/1040603002/diff/60001/src/base/cpu.cc
File src/base/cpu.cc (right):

https://codereview.chromium.org/1040603002/diff/60001/src/base/cpu.cc#newcode52
src/base/cpu.cc:52: // Clear ecx to align with __cpuid() of MSVC:
Nit: Move this comment into the actual function below.

[Jing, 2015-04-08 05:41:47]

On 2015/04/08 04:36:21, Benedikt Meurer wrote:
> Looking good with nit. Can you also fix the two TODO(intel) in
> macro-assembler-x64.cc (MacroAssembler::Lzcntl)?
> 
> https://codereview.chromium.org/1040603002/diff/60001/src/base/cpu.cc
> File src/base/cpu.cc (right):
> 
>
https://codereview.chromium.org/1040603002/diff/60001/src/base/cpu.cc#newcode52
> src/base/cpu.cc:52: // Clear ecx to align with __cpuid() of MSVC:
> Nit: Move this comment into the actual function below.

Thanks for the comments.
PTAL.

[Benedikt Meurer, 2015-04-08 05:45:41]

Err, that was not what I meant. Since we still need to support machines without
LZCNT, it is important to keep the macro assembler functions around, and use
them.

https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
File src/compiler/x64/code-generator-x64.cc (right):

https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
src/compiler/x64/code-generator-x64.cc:709: __ lzcntl(i.OutputRegister(),
i.InputRegister(0));
Keep the macro assembler version here, because we also need to support machines
without lzcntl.

https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
src/compiler/x64/code-generator-x64.cc:711: __ lzcntl(i.OutputRegister(),
i.InputOperand(0));
Same here.

https://codereview.chromium.org/1040603002/diff/80001/src/x64/lithium-codegen...
File src/x64/lithium-codegen-x64.cc (right):

https://codereview.chromium.org/1040603002/diff/80001/src/x64/lithium-codegen...
src/x64/lithium-codegen-x64.cc:4005: __ lzcntl(result, input);
Leave it as Lzcntl here as well.

https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
File src/x64/macro-assembler-x64.cc (left):

https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
src/x64/macro-assembler-x64.cc:2889: // TODO(intel): Add support for LZCNT
(BMI1/ABM).
Keep these functions, because not all machines will support lzcnt. What I meant
was to extend these functions with a special case for LZCNT, i.e.

if (CpuFeatures::IsSupported(LZCNT)) {
  lzcnt(dst, src);
} else {
  old code;
}

https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
File src/x64/macro-assembler-x64.h (left):

https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
src/x64/macro-assembler-x64.h:930: void Lzcntl(Register dst, Register src);
Don't remove these functions.

[Jing, 2015-04-08 06:16:59]

On 2015/04/08 05:45:41, Benedikt Meurer wrote:
> Err, that was not what I meant. Since we still need to support machines
without
> LZCNT, it is important to keep the macro assembler functions around, and use
> them.
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
> File src/compiler/x64/code-generator-x64.cc (right):
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
> src/compiler/x64/code-generator-x64.cc:709: __ lzcntl(i.OutputRegister(),
> i.InputRegister(0));
> Keep the macro assembler version here, because we also need to support
machines
> without lzcntl.
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/compiler/x64/code-g...
> src/compiler/x64/code-generator-x64.cc:711: __ lzcntl(i.OutputRegister(),
> i.InputOperand(0));
> Same here.
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/lithium-codegen...
> File src/x64/lithium-codegen-x64.cc (right):
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/lithium-codegen...
> src/x64/lithium-codegen-x64.cc:4005: __ lzcntl(result, input);
> Leave it as Lzcntl here as well.
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
> File src/x64/macro-assembler-x64.cc (left):
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
> src/x64/macro-assembler-x64.cc:2889: // TODO(intel): Add support for LZCNT
> (BMI1/ABM).
> Keep these functions, because not all machines will support lzcnt. What I
meant
> was to extend these functions with a special case for LZCNT, i.e.
> 
> if (CpuFeatures::IsSupported(LZCNT)) {
>   lzcnt(dst, src);
> } else {
>   old code;
> }
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
> File src/x64/macro-assembler-x64.h (left):
> 
>
https://codereview.chromium.org/1040603002/diff/80001/src/x64/macro-assembler...
> src/x64/macro-assembler-x64.h:930: void Lzcntl(Register dst, Register src);
> Don't remove these functions.

Fixed previous patch set.

[Benedikt Meurer, 2015-04-08 06:22:20]

Thanks. LGTM

[Benedikt Meurer, 2015-04-08 06:50:59]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2015-04-08 06:51:00]

The patchset sent to the CQ was uploaded after l-g-t-m from
weiliang.lin@intel.com
Link to the patchset: https://codereview.chromium.org/1040603002/#ps100001
(title: "Fix previous Patch Set")

[commit-bot: I haz the power, 2015-04-08 06:51:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1040603002/100001

[commit-bot: I haz the power, 2015-04-08 07:15:57]

Committed patchset #6 (id:100001)

[commit-bot: I haz the power, 2015-04-08 07:16:13]

Patchset 6 (id:??) landed as
https://crrev.com/584a351484b7423605b282386225f26622262d8d
Cr-Commit-Position: refs/heads/master@{#27648}