822222 - BaselineCompiler: Add interrupt checks

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jan de Mooij [:jandem]]

Need this to make jit-test/tests/basic/shell-watchdog.js not timeout.

Comment 1

[Jan de Mooij [:jandem]]

Attachment: Part 1: Allow direct VM calls

As we add the more uncommon ops, it's getting annoying to add an ICStub class etc just to perform a VM call. This patch allows making VM calls from the compiler itself, and rewrites DEFVAR to use it. To reuse the return address -> pc mapping mechanism, this patch adds an ICEntry with no stubs. This should avoid a lot of boilerplate code, is faster and avoids allocating stubs.

I can convert some of the other calls in a follow-up patch.

Comment 2

[Jan de Mooij [:jandem]]

Attachment: Part 2: Add interrupt check

Like Ion, emits an interrupt check at every LOOPHEAD op.

Comment 3

[Kannan Vijayan [:djvj]]

Comment on attachment 692952 [details] [diff] [review]
Part 1: Allow direct VM calls

Review of attachment 692952 [details] [diff] [review]:
-----------------------------------------------------------------

Awesome.  I was worried that the generated code for this would be really fat and bloat up the mainline jitcode, but it's pretty slim.

::: js/src/ion/shared/BaselineCompiler-shared.h
@@ +36,5 @@
>      // has been allocated.
> +    struct ICLoadLabel {
> +        size_t icEntry;
> +        CodeOffsetLabel label;
> +    };

Nice.  Generalizing this had to happen sometime :)

Comment 4

[Jan de Mooij [:jandem]]

https://hg.mozilla.org/projects/ionmonkey/rev/31004c39ccf3
https://hg.mozilla.org/projects/ionmonkey/rev/54876ec5e5b8