[turbofan] Change TruncateFloat64ToUint64 to TryTruncateFloatToUint64.

[turbofan] Change TruncateFloat64ToUint64 to TryTruncateFloatToUint64.

This operator now provides a second output which indicates whether the conversion from float64 to uint64 was successful or not. The second output returns 0 if the conversion fails, or something else if the conversion succeeds.

The second output can be ignored, which means that the operator can be used the same as the original operator.

I implement the new operator on x64 and arm64. @v8-mips-ports and @v8-ppc-ports, can you please take care of the mips64 and ppc64 implementation of the second output?

R=titzer@chromium.org, v8-arm-ports@googlegroups.com

Committed: https://crrev.com/c343f30923ab8b9f99d3f565e8ab65837cbb9efb
Cr-Commit-Position: refs/heads/master@{#32705}

[martyn.capewell, 2015-12-07 16:10:33]

martyn.capewell@arm.com changed reviewers:
+ martyn.capewell@arm.com

[martyn.capewell, 2015-12-07 16:10:34]

https://codereview.chromium.org/1507703002/diff/1/src/compiler/arm64/code-gen...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/1507703002/diff/1/src/compiler/arm64/code-gen...
src/compiler/arm64/code-generator-arm64.cc:1058: __ Cset(i.OutputRegister(1),
ge);
You should be able to use conditional compare again here:

if (i.OutputCount() > 1) {
  __ Fcmp(i.InputDoubleRegister(0), 0.0);
  __ CCmp(i.OutputRegister(0), -1, ZFlag, ge);
  __ Cset(i.OutputRegister(1), ne);
}

[ahaas, 2015-12-07 17:03:03]

https://codereview.chromium.org/1507703002/diff/1/src/compiler/arm64/code-gen...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/1507703002/diff/1/src/compiler/arm64/code-gen...
src/compiler/arm64/code-generator-arm64.cc:1058: __ Cset(i.OutputRegister(1),
ge);
On 2015/12/07 at 16:10:34, martyn.capewell wrote:
> You should be able to use conditional compare again here:
> 
> if (i.OutputCount() > 1) {
>   __ Fcmp(i.InputDoubleRegister(0), 0.0);
>   __ CCmp(i.OutputRegister(0), -1, ZFlag, ge);
>   __ Cset(i.OutputRegister(1), ne);
> }

Done

[martyn.capewell, 2015-12-07 18:44:17]

One small nit, then arm64 part lgtm

https://codereview.chromium.org/1507703002/diff/20001/src/compiler/arm64/code...
File src/compiler/arm64/code-generator-arm64.cc (right):

https://codereview.chromium.org/1507703002/diff/20001/src/compiler/arm64/code...
src/compiler/arm64/code-generator-arm64.cc:1056: Label done;
Don't need this Label any more.

[akos.palfi.imgtec, 2015-12-08 21:08:33]

akos.palfi@imgtec.com changed reviewers:
+ akos.palfi@imgtec.com

[akos.palfi.imgtec, 2015-12-08 21:08:33]

@ahaas: We've created the MIPS port: https://codereview.chromium.org/1513463002/
Could you please merge it into this CL?

[titzer, 2015-12-09 07:59:03]

https://codereview.chromium.org/1507703002/diff/40001/src/compiler/x64/instru...
File src/compiler/x64/instruction-selector-x64.cc (right):

https://codereview.chromium.org/1507703002/diff/40001/src/compiler/x64/instru...
src/compiler/x64/instruction-selector-x64.cc:1479: case
IrOpcode::kTryTruncateFloat64ToUint64:
I should have caught this earlier. You shouldn't be doing this this way, because
you are probably emitting multiple copies of the code. You should just remove
these cases.

[ahaas, 2015-12-09 10:05:09]

I added the MIPS64 implementation from CL
https://codereview.chromium.org/1513463002.

https://codereview.chromium.org/1507703002/diff/40001/src/compiler/x64/instru...
File src/compiler/x64/instruction-selector-x64.cc (right):

https://codereview.chromium.org/1507703002/diff/40001/src/compiler/x64/instru...
src/compiler/x64/instruction-selector-x64.cc:1479: case
IrOpcode::kTryTruncateFloat64ToUint64:
On 2015/12/09 at 07:59:03, titzer wrote:
> I should have caught this earlier. You shouldn't be doing this this way,
because you are probably emitting multiple copies of the code. You should just
remove these cases.

Done.

[titzer, 2015-12-09 10:48:48]

lgtm

[ahaas, 2015-12-09 11:04:17]

The CQ bit was checked by ahaas@chromium.org

[ahaas, 2015-12-09 11:04:17]

The patchset sent to the CQ was uploaded after l-g-t-m from
martyn.capewell@arm.com
Link to the patchset: https://codereview.chromium.org/1507703002/#ps60001
(title: "Added mips64 implementation, fixed nits.")

[commit-bot: I haz the power, 2015-12-09 11:04:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1507703002/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1507703002/60001

[commit-bot: I haz the power, 2015-12-09 11:15:24]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2015-12-09 11:16:09]

Description was changed from

==========
[turbofan] Change TruncateFloat64ToUint64 to TryTruncateFloatToUint64.

This operator now provides a second output which indicates whether the
conversion from float64 to uint64 was successful or not. The second output
returns 0 if the conversion fails, or something else if the conversion succeeds.

The second output can be ignored, which means that the operator can be used the
same as the original operator.

I implement the new operator on x64 and arm64. @v8-mips-ports and @v8-ppc-ports,
can you please take care of the mips64 and ppc64 implementation of the second
output?

R=titzer@chromium.org, v8-arm-ports@googlegroups.com
==========

to

==========
[turbofan] Change TruncateFloat64ToUint64 to TryTruncateFloatToUint64.

This operator now provides a second output which indicates whether the
conversion from float64 to uint64 was successful or not. The second output
returns 0 if the conversion fails, or something else if the conversion succeeds.

The second output can be ignored, which means that the operator can be used the
same as the original operator.

I implement the new operator on x64 and arm64. @v8-mips-ports and @v8-ppc-ports,
can you please take care of the mips64 and ppc64 implementation of the second
output?

R=titzer@chromium.org, v8-arm-ports@googlegroups.com

Committed: https://crrev.com/c343f30923ab8b9f99d3f565e8ab65837cbb9efb
Cr-Commit-Position: refs/heads/master@{#32705}
==========

[commit-bot: I haz the power, 2015-12-09 11:16:10]

Patchset 4 (id:??) landed as
https://crrev.com/c343f30923ab8b9f99d3f565e8ab65837cbb9efb
Cr-Commit-Position: refs/heads/master@{#32705}