Bug 182368 – When BytecodeParser inserts Unreachable after ForceOSRExit it needs to update ArgumentPositions for Flushes it inserts

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Saam Barati]

...

[Saam Barati]

<rdar://problem/36932466>

[Saam Barati]

Created attachment 332833 [details]
patch

[Saam Barati]

Created attachment 332835 [details]
patch

[Saam Barati]

Created attachment 332839 [details]
patch

[Saam Barati]

Created attachment 332895 [details]
patch

[Mark Lam]

Comment on attachment 332895 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=332895&action=review

r=me with a suggestion.

> Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp:6679
> +                        VirtualRegister argument = operand - (inlineCallFrame ? inlineCallFrame->stackOffset : 0);
> +                        if (argument.isArgument() && !argument.isHeader()) {
> +                            const Vector<ArgumentPosition*>& arguments = m_inlineCallFrameToArgumentPositions.get(inlineCallFrame);
> +                            arguments[argument.toArgument()]->addVariable(variable);
> +                        }

If this is only needed when we create a new VAD, maybe you can move this into the body of the if statement above.

[Saam Barati]

Comment on attachment 332895 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=332895&action=review

>> Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp:6679
>> +                        }
> 
> If this is only needed when we create a new VAD, maybe you can move this into the body of the if statement above.

Spoke to Mark offline about this:
We want to tell this ArgumentPosition about this VAD regardless of whether we added it or not. From reading other code in the bytecode parser, I believe it's possible that this VAD is from GetLocal only, and the ArgumentPosition would not know about it.

[WebKit Commit Bot]

Comment on attachment 332895 [details]
patch

Clearing flags on attachment: 332895

Committed r228031: <https://trac.webkit.org/changeset/228031>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.