[wasm] sundry trap handler fixes

[wasm] sundry trap handler fixes

This CL includes several small bug fixes for trap handlers. Among the changes:

* Use the correct representation for ProtectedLoads, enabling protected loads of
  floating point types.

* Including the protected instruction list in what gets serialized for Code
  objects. This is needed to allow deserialization for Wasm modules to work.

* Get the context needed to through and exception from the Isolate rather than
  getting it as a parameter to the Protected instructions. Passing it in as an
  argument is problematic when code is compiled ahead of time, as the context
  may not be known yet. The new approach is similar to how it works for TrapIf
  and TrapUnless.

BUG= https://bugs.chromium.org/p/v8/issues/detail?id=5277

Review-Url: https://codereview.chromium.org/2591903002
Cr-Commit-Position: refs/heads/master@{#41907}
Committed: https://chromium.googlesource.com/v8/v8/+/5fa423d7c28cfb058293cd2b1c21e6fd4df4813f

[Eric Holk, 2016-12-21 00:24:29]

eholk@chromium.org changed reviewers:
+ bradnelson@chromium.org, mtrofin@chromium.org, titzer@chromium.org

[titzer, 2016-12-21 08:51:39]

Nice simplification!

LGTM if comments are addressed.

https://codereview.chromium.org/2591903002/diff/20001/src/compiler/x64/instru...
File src/compiler/x64/instruction-selector-x64.cc (right):

https://codereview.chromium.org/2591903002/diff/20001/src/compiler/x64/instru...
src/compiler/x64/instruction-selector-x64.cc:250: void
InstructionSelector::VisitLoad(Node* node) {
Looks like VisitLoad and VisitProtectedLoad are now identical except for the
X64MemoryOperation misc field. Collapse into a single routine?

[Eric Holk, 2016-12-22 00:01:44]

https://codereview.chromium.org/2591903002/diff/20001/src/compiler/x64/instru...
File src/compiler/x64/instruction-selector-x64.cc (right):

https://codereview.chromium.org/2591903002/diff/20001/src/compiler/x64/instru...
src/compiler/x64/instruction-selector-x64.cc:250: void
InstructionSelector::VisitLoad(Node* node) {
On 2016/12/21 08:51:39, titzer wrote:
> Looks like VisitLoad and VisitProtectedLoad are now identical except for the
> X64MemoryOperation misc field. Collapse into a single routine?

Done.

There's also an additional argument to ProtectedLoad for the source position, so
I added that into VisitLoad as well. I kept VisitProtectedLoad as a separate
function that calls VisitLoad because VisitProtectedLoad is automatically
declared by a macro, and perhaps these functions will be more different on
another platform.

[Eric Holk, 2016-12-22 00:02:16]

The CQ bit was checked by eholk@chromium.org

[Eric Holk, 2016-12-22 00:02:16]

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/2591903002/#ps40001
(title: "Merge VisitLoad and VisitProtectedLoad")

[commit-bot: I haz the power, 2016-12-22 00:02:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-22 00:31:59]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1482364936130820,
"parent_rev": "c46f98bcedb600538e9b41ad3179ebaa724e86c4", "commit_rev":
"5fa423d7c28cfb058293cd2b1c21e6fd4df4813f"}

[commit-bot: I haz the power, 2016-12-22 00:32:06]

Description was changed from

==========
[wasm] sundry trap handler fixes

This CL includes several small bug fixes for trap handlers. Among the changes:

* Use the correct representation for ProtectedLoads, enabling protected loads of
  floating point types.

* Including the protected instruction list in what gets serialized for Code
  objects. This is needed to allow deserialization for Wasm modules to work.

* Get the context needed to through and exception from the Isolate rather than
  getting it as a parameter to the Protected instructions. Passing it in as an
  argument is problematic when code is compiled ahead of time, as the context
  may not be known yet. The new approach is similar to how it works for TrapIf
  and TrapUnless.

BUG= https://bugs.chromium.org/p/v8/issues/detail?id=5277
==========

to

==========
[wasm] sundry trap handler fixes

This CL includes several small bug fixes for trap handlers. Among the changes:

* Use the correct representation for ProtectedLoads, enabling protected loads of
  floating point types.

* Including the protected instruction list in what gets serialized for Code
  objects. This is needed to allow deserialization for Wasm modules to work.

* Get the context needed to through and exception from the Isolate rather than
  getting it as a parameter to the Protected instructions. Passing it in as an
  argument is problematic when code is compiled ahead of time, as the context
  may not be known yet. The new approach is similar to how it works for TrapIf
  and TrapUnless.

BUG= https://bugs.chromium.org/p/v8/issues/detail?id=5277

Review-Url: https://codereview.chromium.org/2591903002
Cr-Commit-Position: refs/heads/master@{#41907}
Committed:
https://chromium.googlesource.com/v8/v8/+/5fa423d7c28cfb058293cd2b1c21e6fd4df...
==========

[commit-bot: I haz the power, 2016-12-22 00:32:06]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/v8/v8/+/5fa423d7c28cfb058293cd2b1c21e6fd4df...