[WASM-Function-References] Add support for (ref.null heaptype)

[Dmitry]

Function references proposal introduces new form of ref.null instruction that can take <heaptype> immediate.
To fully support the proposal we need to add new form of ref.null.

[Radar WebKit Bug Importer]

<rdar://problem/82816107>

[Dmitry]

Created attachment 440184 [details]
Patch

[Dmitry]

Created attachment 440187 [details]
Patch

[Dmitry]

Created attachment 442681 [details]
Patch

[Yusuke Suzuki]

Comment on attachment 442681 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=442681&action=review

r=me with nit.

> Source/JavaScriptCore/wasm/WasmAirIRGenerator.cpp:3456
> +    append(Move, Arg::bigImm(JSValue::encode(jsNull())), tmp1);
> +    append(Compare64, Arg::relCond(MacroAssembler::Equal), calleeFunction, tmp1, tmp2);
> +    emitCheck([&] {
> +        return Inst(BranchTest32, nullptr, Arg::resCond(MacroAssembler::NonZero), tmp2, tmp2);
> +    }, [=] (CCallHelpers& jit, const B3::StackmapGenerationParams&) {
> +        this->emitThrowException(jit, ExceptionType::NullReference);
> +    });

We should use Branch64 instead of Compare64 and BranchTest32.

[Dmitry]

Created attachment 442794 [details]
Patch

[Yusuke Suzuki]

Comment on attachment 442794 [details]
Patch

r=me

[EWS]

Committed r285065 (243707@main): <https://commits.webkit.org/243707@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 442794 [details].