[wasm] Provide backoff implementations for the Fxx rounding instructions

[wasm] Provide backoff implementations for the Fxx rounding instructions

If the architecture does not provide rounding instructions, then C
implementations of these rounding instructions are called. The C
implementations from math.h are used, function pointers are registered
as external references so that they can be call from the simulator.

R=titzer@chromium.org

BUG=575379
LOG=Y

Committed: https://crrev.com/23943d0e00f2a9699eef7b1c1417c8685dba77e5
Cr-Commit-Position: refs/heads/master@{#33677}

[titzer, 2016-02-02 10:04:22]

On 2016/02/02 09:30:23, ahaas wrote:

lgtm

[ahaas, 2016-02-02 12:06:33]

The CQ bit was checked by ahaas@chromium.org

[ahaas, 2016-02-02 12:06:33]

The patchset sent to the CQ was uploaded after l-g-t-m from titzer@chromium.org
Link to the patchset: https://codereview.chromium.org/1661463002/#ps20001
(title: "rebase.")

[commit-bot: I haz the power, 2016-02-02 12:06:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1661463002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1661463002/20001

[ahaas, 2016-02-02 12:14:59]

ahaas@chromium.org changed reviewers:
+ yangguo@chromium.org

[commit-bot: I haz the power, 2016-02-02 12:16:33]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-02-02 12:16:33]

Try jobs failed on following builders:
  v8_presubmit on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/10427)

[Yang, 2016-02-02 12:20:33]

On 2016/02/02 12:16:33, commit-bot: I haz the power wrote:
> Try jobs failed on following builders:
>   v8_presubmit on tryserver.v8 (JOB_FAILED,
> http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/10427)

snapshot lgtm.

[ahaas, 2016-02-02 12:20:59]

The CQ bit was checked by ahaas@chromium.org

[commit-bot: I haz the power, 2016-02-02 12:21:16]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1661463002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1661463002/20001

[commit-bot: I haz the power, 2016-02-02 12:26:52]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-02-02 12:27:09]

Description was changed from

==========
[wasm] Provide backoff implementations for the Fxx rounding instructions

If the architecture does not provide rounding instructions, then C
implementations of these rounding instructions are called. The C
implementations from math.h are used, function pointers are registered
as external references so that they can be call from the simulator.

R=titzer@chromium.org

BUG=575379

LOG=Y
==========

to

==========
[wasm] Provide backoff implementations for the Fxx rounding instructions

If the architecture does not provide rounding instructions, then C
implementations of these rounding instructions are called. The C
implementations from math.h are used, function pointers are registered
as external references so that they can be call from the simulator.

R=titzer@chromium.org

BUG=575379

LOG=Y

Committed: https://crrev.com/23943d0e00f2a9699eef7b1c1417c8685dba77e5
Cr-Commit-Position: refs/heads/master@{#33677}
==========

[commit-bot: I haz the power, 2016-02-02 12:27:10]

Patchset 2 (id:??) landed as
https://crrev.com/23943d0e00f2a9699eef7b1c1417c8685dba77e5
Cr-Commit-Position: refs/heads/master@{#33677}