1290421 - wasm: Throw on OOB at the MIR graph level if we know we will

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Benjamin Bouvier [:bbouvier] (inactive)]

Attachment: throw-oob.patch

This:
- renames MAsmThrowUnreachable to MWasmTrap, gives it a wasm::Trap parameter.
- uses it to throw on a memory access if the offset is > INT32_MAX, at the MIR graph level, simplifying slightly WasmLoad/Store/BoundsCheck codegen.

Comment 1

[Dan Gohman [:sunfish]]

Comment on attachment 8775916 [details] [diff] [review]
throw-oob.patch

Review of attachment 8775916 [details] [diff] [review]:
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Hopefully we won't see a lot of code with statically out-of-bounds memory accesses, of course :-).

Comment 2

[Dan Gohman [:sunfish]]

The patch for bug 1293312 is adding another place that this patch will want to cover.

Comment 3

[Benjamin Bouvier [:bbouvier] (inactive)]

Thanks for the heads-up!

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/019c4896543a
Throw ahead of time on statically known out-of-bounds; r=sunfish

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/019c4896543a