MIPS64: Fix random failures of fannkuch.js.

MIPS64: Fix random failures of fannkuch.js.

TEST=mjsunit/asm/embenchen/fannkuch,
     mjsunit/math-abs
BUG=

Committed: https://crrev.com/e8173e4ea2fd4b98d2f4c62fbae55b4831f388fb
Cr-Commit-Position: refs/heads/master@{#29157}

[dusmil.imgtec, 2015-06-19 13:40:05]

dusan.milosavljevic@imgtec.com changed reviewers:
+ akos.palfi@imgtec.com, balazs.kilvady@imgtec.com, bmeurer@chromium.org,
jkummerow@google.com, paul.lind@imgtec.com

[dusmil.imgtec, 2015-06-19 13:40:06]

PTAL.

[paul.l..., 2015-06-19 13:45:19]

LGTM. We need v8 team review of the regression test addition, PTAL.

[Jakob Kummerow, 2015-06-19 14:50:25]

jkummerow@chromium.org changed reviewers:
+ jkummerow@chromium.org

[Jakob Kummerow, 2015-06-19 14:50:25]

LGTM with comments.

I'm shocked that we didn't have test coverage for Math.abs(kMinInt) yet.

https://codereview.chromium.org/1192413002/diff/1/test/mjsunit/math-abs.js
File test/mjsunit/math-abs.js (right):

https://codereview.chromium.org/1192413002/diff/1/test/mjsunit/math-abs.js#ne...
test/mjsunit/math-abs.js:134: // that sould overflow.
nit: s/sould/should/

https://codereview.chromium.org/1192413002/diff/1/test/mjsunit/math-abs.js#ne...
test/mjsunit/math-abs.js:136: for (i = 0; i < 1000; i++) {
Please keep the testcase fast:

assertEquals(2147483648, absHalf(bits));
assertEquals(2147483648, absHalf(bits));
%OptimizeFunctionOnNextCall(absHalf);
assertEquals(2147483648, absHalf(bits));

[dusmil.imgtec, 2015-06-19 15:45:52]

The CQ bit was checked by dusan.milosavljevic@imgtec.com

[dusmil.imgtec, 2015-06-19 15:45:53]

The patchset sent to the CQ was uploaded after l-g-t-m from
jkummerow@chromium.org, paul.lind@imgtec.com
Link to the patchset: https://codereview.chromium.org/1192413002/#ps40001
(title: "Addressed comments 2.")

[commit-bot: I haz the power, 2015-06-19 15:46:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1192413002/40001

[commit-bot: I haz the power, 2015-06-19 16:11:49]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-06-19 16:12:03]

Patchset 3 (id:??) landed as
https://crrev.com/e8173e4ea2fd4b98d2f4c62fbae55b4831f388fb
Cr-Commit-Position: refs/heads/master@{#29157}