Bug 210253 – Web Inspector: Debugger: debug hooks should also be emitted for the first sub-expression in a comma expression

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Inspector

[Devin Rousso]

After r259781, debug hooks are now generated for all but the first sub-expression in a comma expression.

[Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp](http://trac.webkit.org/changeset/259781/webkit/trunk/Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp):
```
    RegisterID* CommaNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
    {
        for (; node->next(); node = node->next()) {
            generator.emitNode(generator.ignoredResult(), node->m_expr);

            // Don't emit a debug hook for the first expression, as that should've already happened in
            // the containing statement.
            generator.emitDebugHook(node->next()->m_expr);
        }
        return generator.emitNodeInTailPosition(dst, node->m_expr);
    }
```

This comment is inaccurate, as in the simple case of `true && (a(), b())`.

[Devin Rousso]

Created attachment 395920 [details]
Patch

[Joseph Pecoraro]

Comment on attachment 395920 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=395920&action=review

r=me

> Source/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp:3539
>      if (!shouldEmitDebugHooks())
>          return;

Maybe we could use LIKELY macros here.

[Devin Rousso]

Created attachment 395963 [details]
Patch

[Devin Rousso]

Comment on attachment 395963 [details]
Patch

Oops, that should be a `LIKELY` 😅

[Devin Rousso]

Created attachment 395967 [details]
Patch

[EWS]

Committed r259810: <https://trac.webkit.org/changeset/259810>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 395967 [details].

[Radar WebKit Bug Importer]

<rdar://problem/61528617>