Allow looser heap accesses historically emitted by Emscripten.

Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N

Committed: https://crrev.com/f9ee14e5198e2f44ad3789389e89a527022a3fdd
Cr-Commit-Position: refs/heads/master@{#33964}

[bradnelson, 2016-02-12 19:46:56]

The CQ bit was checked by bradnelson@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-02-12 19:47:05]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1692713006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1692713006/1

[commit-bot: I haz the power, 2016-02-12 20:01:44]

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

[commit-bot: I haz the power, 2016-02-12 20:01:45]

Dry run: Try jobs failed on following builders:
  v8_linux_nodcheck_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel/build...)

[bradn, 2016-02-13 02:15:47]

Description was changed from

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[HEAP32[..]|0]
As opposed to the spec legal construct:
HEAP8[HEAP32[..]>>0]

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N
==========

to

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N
==========

[bradn, 2016-02-13 02:28:03]

The CQ bit was checked by bradnelson@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-02-13 02:28:10]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1692713006/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1692713006/20001

[bradn, 2016-02-13 02:29:25]

Actually revised slightly, the asm behavior was more general than I'd realized.

[commit-bot: I haz the power, 2016-02-13 02:49:36]

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

[commit-bot: I haz the power, 2016-02-13 02:49:37]

Dry run: This issue passed the CQ dry run.

[aseemgarg, 2016-02-13 03:02:40]

lgtm

I am not sure though that we should be supporting this. I guess we can try to
run this in Firefox and if they don't allow it, we can fail too (it will anyways
work without going through asm pipeline)? If we do, might be useful to push to
get this added as part of the spec itself.

[bradn, 2016-02-13 06:19:33]

I've just double checked this test in particular works in firefox.
In addition so does embenchen, which has this sort of thing.

[bradn, 2016-02-13 06:19:45]

The CQ bit was checked by bradnelson@google.com

[commit-bot: I haz the power, 2016-02-13 06:19:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1692713006/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1692713006/20001

[commit-bot: I haz the power, 2016-02-13 06:21:03]

Description was changed from

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N
==========

to

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N
==========

[commit-bot: I haz the power, 2016-02-13 06:21:03]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-02-13 06:21:39]

Description was changed from

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N
==========

to

==========
Allow looser heap accesses historically emitted by Emscripten.

Older versions of Emscripten appear to emit Asm.js containing:
HEAP8[x] with x in int
As opposed to the spec legal construct:
HEAP8[x>>0] with x in int

As older programs and even benchmarks such as Embenchen
include these constructs, support them for compatibility.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator,mjsunit/asm-wasm
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N

Committed: https://crrev.com/f9ee14e5198e2f44ad3789389e89a527022a3fdd
Cr-Commit-Position: refs/heads/master@{#33964}
==========

[commit-bot: I haz the power, 2016-02-13 06:21:40]

Patchset 2 (id:??) landed as
https://crrev.com/f9ee14e5198e2f44ad3789389e89a527022a3fdd
Cr-Commit-Position: refs/heads/master@{#33964}