818042 - BaselineCompiler: Compile GETPROP

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Comment 1

[Jan de Mooij [:jandem]]

Attachment: patch

Slow path to handle GETPROP/CALLPROP/LENGTH. CALLPROP is used with SWAP, so the patch adds that one too since it's so simple.

Comment 2

[Kannan Vijayan [:djvj]]

Comment on attachment 688249 [details] [diff] [review]
patch

Review of attachment 688249 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/ion/BaselineCompiler.cpp
@@ +249,5 @@
>  bool
> +BaselineCompiler::emit_JSOP_SWAP()
> +{
> +    // Keep top stack values in R0 and R1.
> +    frame.popRegsAndSync(2);

Are there any situations where we expect that more than two unsynced values on the stack?  If there are, we could make this more efficient by excluding an unnecessary sync by hardcoding the stack manipulation in that case.

Don't think it's a big deal, but it occurred to me when reviewing.

Comment 3

[Jan de Mooij [:jandem]]

https://hg.mozilla.org/projects/ionmonkey/rev/163971bbdc1e

(In reply to Kannan Vijayan [:djvj] from comment #2)
> Are there any situations where we expect that more than two unsynced values
> on the stack?

Not in this case since SWAP immediately follows a CALLPROP. If there are other cases where SWAP is used, we could look into that though.