Enable debug builds with some optimizations turned on.

Enable debug builds with some optimizations turned on.

A new gyp variable 'v8_optimized_debug' can be set to 1 in order to turn on optimization level 1 for debug builds. With the default (=0), it builds in debug mode like before.

The intention is to run some bots on the waterfall with this configuration. Tests have a x5 speed-up like that.

R=jkummerow@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=15599

[Michael Achenbach, 2013-07-09 12:18:40]

PTAL

[Jakob Kummerow, 2013-07-09 12:21:06]

What about Windows and Mac?

[Michael Achenbach, 2013-07-09 14:00:44]

On 2013/07/09 12:21:06, Jakob wrote:
> What about Windows and Mac?

There you go. PTAL.

[Jakob Kummerow, 2013-07-09 16:47:07]

LGTM with comments.

https://codereview.chromium.org/18516012/diff/4001/build/common.gypi
File build/common.gypi (right):

https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode507
build/common.gypi:507: 'msvs_settings': {
Keeping the msvs_settings section where it was saves two levels of indentation.
It's safe to have it outside an OS=="win" conditional, since the section is
ignored by other GYP generators anyway.
I don't feel strongly about this though.

https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode519
build/common.gypi:519: }]
nit: trailing comma (not necessary for correctness, but we're pretty consistent
about putting it in nevertheless).

https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode533
build/common.gypi:533: }]
nit: trailing comma

https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode561
build/common.gypi:561: }]
nit: trailing comma

[Michael Achenbach, 2013-07-10 13:04:23]

On 2013/07/09 16:47:07, Jakob wrote:
> LGTM with comments.
> 
> https://codereview.chromium.org/18516012/diff/4001/build/common.gypi
> File build/common.gypi (right):
> 
>
https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode507
> build/common.gypi:507: 'msvs_settings': {
> Keeping the msvs_settings section where it was saves two levels of
indentation.
> It's safe to have it outside an OS=="win" conditional, since the section is
> ignored by other GYP generators anyway.
> I don't feel strongly about this though.
> 
>
https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode519
> build/common.gypi:519: }]
> nit: trailing comma (not necessary for correctness, but we're pretty
consistent
> about putting it in nevertheless).
> 
>
https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode533
> build/common.gypi:533: }]
> nit: trailing comma
> 
>
https://codereview.chromium.org/18516012/diff/4001/build/common.gypi#newcode561
> build/common.gypi:561: }]
> nit: trailing comma
Done. Copied also most of the optimizaions from
https://codereview.chromium.org/18431003/

[Jakob Kummerow, 2013-07-10 13:24:54]

still LGTM

https://codereview.chromium.org/18516012/diff/15001/build/toolchain.gypi
File build/toolchain.gypi (right):

https://codereview.chromium.org/18516012/diff/15001/build/toolchain.gypi#newc...
build/toolchain.gypi:526: '-O0',
I don't see why this change makes sense.

[Michael Achenbach, 2013-07-10 13:28:01]

On 2013/07/10 13:24:54, Jakob wrote:
> still LGTM
> 
> https://codereview.chromium.org/18516012/diff/15001/build/toolchain.gypi
> File build/toolchain.gypi (right):
> 
>
https://codereview.chromium.org/18516012/diff/15001/build/toolchain.gypi#newc...
> build/toolchain.gypi:526: '-O0',
> I don't see why this change makes sense.

Me neither - I removed it now.

[Michael Achenbach, 2013-07-10 15:21:49]

Committed patchset #4 manually as r15599 (presubmit successful).

[Nico, 2013-07-17 03:13:43]

fyi:

https://codereview.chromium.org/18516012/diff/19001/build/toolchain.gypi
File build/toolchain.gypi (right):

https://codereview.chromium.org/18516012/diff/19001/build/toolchain.gypi#newc...
build/toolchain.gypi:513: 'GCC_STRICT_ALIASING': 'YES',
Note that strict aliasing is only done at -O2 or higher (and on recent clangs
it's on by default with -O2 too). So setting GCC_STRICT_ALIASING here doesn't
really do anything.