896783 - Make IonSpewer and IonGraph output the branch profiling data for each MBasicBlock

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Wei Wu [:wuwei UTC+8]]

Bug 877878 introduces branch profiles for IonMonkey. The value of block counters collected by instrumenting baseline generated code will be copied to related MBasicBlocks after MIRGraph has been built. It might be good to print branch profiling data for each block, which makes subsequent analysis/debugging easier.

Comment 1

[Wei Wu [:wuwei UTC+8]]

Attachment: letIonSpewerSeeBranchProfiles.patch

This patch let JSONSpewer outputs block counters for each MBasicBlock and LBlock.

It depends on bug 877878.

Comment 2

[Wei Wu [:wuwei UTC+8]]

Attachment: letIonGraphSeeBranchProfiles.patch

This patch let IonGraph show block counters for each MBasicBlock and LBlock.

This patch won't break IonGraph when branch profiles are unavailable. Since IonGraph is on github rather than mozilla, I also sent a pull request to sstangl (on github). This patch is for feedback only.

Comment 3

[Sean Stangl [:sstangl]]

Comment on attachment 780926 [details] [diff] [review]
letIonGraphSeeBranchProfiles.patch

Review of attachment 780926 [details] [diff] [review]:
-----------------------------------------------------------------

Handling on Github (https://github.com/lazyparser/iongraph/commit/060bb40ad15f72130ad3b686506c0faf6ab3e1f3#commitcomment-3720687)

Comment 4

[Nicolas B. Pierron [:nbp]]

Comment on attachment 780882 [details] [diff] [review]
letIonSpewerSeeBranchProfiles.patch

Review of attachment 780882 [details] [diff] [review]:
-----------------------------------------------------------------

This patch is good to land, as soon as Bug 877878 patch is landed.

::: js/src/ion/JSONSpewer.cpp
@@ +404,5 @@
>          beginObject();
>          integerProperty("number", bno);
> +
> +        LBlock *lir = regalloc->graph.getBlock(bno);
> +        

nit: remove trailing whitespace here.

Comment 5

[Wei Wu [:wuwei UTC+8]]

This bug was a supplement feature for bug 877878, which will not land.