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Merged
merged 1 commit into from
Nov 12, 2022
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pulkomandy
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Remove code that isn't in the windows version of WebKitLegacy. However this is not sufficient, the infinite loop is gone but now we get a crash in BReferenceable at exit because some objects are still being referenced.

Remove code that isn't in the windows version of WebKitLegacy. However
this is not sufficient, the infinite loop is gone but now we get a crash
in BReferenceable at exit because some objects are still being
referenced.
@lonemadmax
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I've had both the loop and the crash (very, very seldom) without this patch. No loops and no crashes with the patch yet, even visiting google image search results or youtube. Any known way to improve the fail ratio?. What I've noticed, though, is that sometimes on quit there's a variable delay (up to a minute) between window close and app finally quitting.

Anyway, I guess the BReferenceable crash is 17960, predating this code and the last few merges?

@pulkomandy
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Ok then, let's merge this and see if we can find some info about the BReferenceable problem later…

@pulkomandy pulkomandy merged commit c36bc87 into haiku Nov 12, 2022
pulkomandy pushed a commit that referenced this pull request Nov 22, 2022
…a rejected promise

https://bugs.webkit.org/show_bug.cgi?id=247785
rdar://102325201

Reviewed by Yusuke Suzuki.

Rest parameter should be caught in async function. So, running this
JavaScript program should print "caught".
```
async function f(...[[]]) { }
f().catch(e => print("caught"));
```

V8 (used console.log)
```
$ node input.js
caught
```

GraalJS
```
$ js input.js
caught
```

https://tc39.es/ecma262/#sec-async-function-definitions
...
AsyncFunctionDeclaration[Yield, Await, Default] :
    async [no LineTerminator here] function BindingIdentifier[?Yield, ?Await] ( FormalParameters[~Yield, +Await] ) { AsyncFunctionBody }
    [+Default] async [no LineTerminator here] function ( FormalParameters[~Yield, +Await] ) { AsyncFunctionBody }

AsyncFunctionExpression :
    async [no LineTerminator here] function BindingIdentifier[~Yield, +Await]opt ( FormalParameters[~Yield, +Await] ) { AsyncFunctionBody }
...

According to the spec, it indicates `FormalParameters` is used for Async
Function, where `FormalParameters` can be converted to `FunctionRestParameter`.

https://tc39.es/ecma262/#sec-parameter-lists
...
FormalParameters[Yield, Await] :
    [empty]
    FunctionRestParameter[?Yield, ?Await]
    FormalParameterList[?Yield, ?Await]
    FormalParameterList[?Yield, ?Await] ,
    FormalParameterList[?Yield, ?Await] , FunctionRestParameter[?Yield, ?Await]
...

And based on RS: EvaluateAsyncFunctionBody, it will invoke the promise.reject
callback function with abrupt value ([[value]] of non-normal completion record).

https://tc39.es/ecma262/#sec-runtime-semantics-evaluateasyncfunctionbody
...
2. Let declResult be Completion(FunctionDeclarationInstantiation(functionObject, argumentsList)).
3. If declResult is an abrupt completion, then
    a. Perform ! Call(promiseCapability.[[Reject]], undefined, « declResult.[[Value]] »).
...

In that case, any non-normal results of evaluating rest parameters should be
caught and passed to the reject callback function.

To resolve this problem, we should allow the emitted RestParameterNode be wrapped
by the catch handler for promise. However, we should remove `m_restParameter` and
emit rest parameter byte code in `initializeDefaultParameterValuesAndSetupFunctionScopeStack`
if we can prove that change has no side effect. In that case, we can only use one
exception handler.

Current fix is to add another exception handler. And move the handler byte codes to
the bottom of code block in order to make other byte codes as much compact as possible.

Input:
```
async function f(arg0, ...[[]]) { }
f();
```

Dumped Byte Codes:
```
...

bb#2
Predecessors: [ #1 ]
[  20] mov                dst:loc9, src:<JSValue()>(const0)
...

bb#3
Predecessors: [ #2 ]
[  29] get_rest_length    dst:loc11, numParametersToSkip:1
...

bb#12
Predecessors: [ #8 #9 #10 ]
[ 138] new_func_exp       dst:loc10, scope:loc4, functionDecl:0
...

bb#13
Predecessors: [ ]
[ 170] catch              exception:loc10, thrownValue:loc8
[ 174] jmp                targetLabel:8(->182)
Successors: [ #15 ]

bb#14
Predecessors: [ #7 #11 ]
[ 176] catch              exception:loc10, thrownValue:loc8
[ 180] jmp                targetLabel:2(->182)
Successors: [ #15 ]

bb#15
Predecessors: [ #13 #14 ]
[ 182] mov                dst:loc12, src:Undefined(const1)
...

Exception Handlers:
	 1: { start: [  20] end: [  29] target: [ 170] } synthesized catch
	 2: { start: [  29] end: [ 138] target: [ 176] } synthesized catch
```

* JSTests/stress/catch-rest-parameter.js: Added.
(throwError):
(shouldThrow):
(async f):
(throwError.async f):
(throwError.async let):
(async let):
(x.async f):
(x):
(async shouldThrow):
* Source/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp:
(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::initializeDefaultParameterValuesAndSetupFunctionScopeStack):
* Source/JavaScriptCore/bytecompiler/BytecodeGenerator.h:

Canonical link: https://commits.webkit.org/256864@main
@waddlesplash waddlesplash deleted the fix_infinite_loop branch November 29, 2022 21:34
pulkomandy pushed a commit that referenced this pull request Mar 5, 2023
https://bugs.webkit.org/show_bug.cgi?id=251063
rdar://104585575

Reviewed by Mark Lam and Justin Michaud.

This patch enhances CallFrame::dump to support wasm frames in btjs stacktrace.
The example is as follows.

    frame #0: 0x00000001035fca78 JavaScriptCore`JSC::functionBreakpoint(globalObject=0x000000012f410068, callFrame=0x000000016fdfa9d0) at JSDollarVM.cpp:2273:9 [opt]
    frame #1: 0x000000010ec44204 0x10eccc5dc
    frame #2: 0x000000010eccc5dc callback#Dwaxn6 [Baseline bc#50](Undefined)
    frame #3: 0x000000010ec4ca84 wasm-stub [WasmToJS](Wasm::Instance: 0x10d29da40)
    frame #4: 0x000000010ed0c060 <?>.wasm-function[1] [OMG](Wasm::Instance: 0x10d29da40)
    frame #5: 0x000000010ed100d0 jsToWasm#CWTx6k [FTL bc#22](Cell[JSModuleEnvironment]: 0x12f524540, Cell[WebAssemblyFunction]: 0x10d06a3a8, 1, 2, 3)
    frame #6: 0x000000010ec881b0 #D5ymZE [Baseline bc#733](Undefined, Cell[Generator]: 0x12f55c180, 1, Cell[Object]: 0x12f69dfc0, 0, Cell[JSLexicalEnvironment]: 0x12f52cee0)
    frame #7: 0x000000010ec3c008 asyncFunctionResume#A4ayYg [LLInt bc#49](Undefined, Cell[Generator]: 0x12f55c180, Cell[Object]: 0x12f69dfc0, 0)
    frame #8: 0x000000010ec3c008 promiseReactionJobWithoutPromise#D0yDF1 [LLInt bc#25](Undefined, Cell[Function]: 0x12f44f3c0, Cell[Object]: 0x12f69dfc0, Cell[Generator]: 0x12f55c180)
    frame #9: 0x000000010ec80ec0 promiseReactionJob#EdShZz [Baseline bc#74](Undefined, Undefined, Cell[Function]: 0x12f44f3c0, Cell[Object]: 0x12f69dfc0, Cell[Generator]: 0x12f55c180)
    frame #10: 0x000000010ec3c728
    frame #11: 0x0000000103137560 JavaScriptCore`JSC::Interpreter::executeCall(JSC::JSGlobalObject*, JSC::JSObject*, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) [inlined] JSC::JITCode::execute(this=<unavailable>, vm=<unavailable>, protoCallFrame=<unavailable>) at JITCodeInlines.h:42:38 [opt]
    frame #12: 0x0000000103137524 JavaScriptCore`JSC::Interpreter::executeCall(this=<unavailable>, lexicalGlobalObject=<unavailable>, function=<unavailable>, callData=<unavailable>, thisValue=<unavailable>, args=<unavailable>) at Interpreter.cpp:1093:27 [opt]
    frame #13: 0x000000010349d6d0 JavaScriptCore`JSC::runJSMicrotask(globalObject=0x000000012f410068, identifier=(m_identifier = 81), job=JSValue @ x22, argument0=JSValue @ x26, argument1=JSValue @ x25, argument2=<unavailable>, argument3=<unavailable>) at JSMicrotask.cpp:98:9 [opt]
    frame #14: 0x00000001039dfc54 JavaScriptCore`JSC::VM::drainMicrotasks() (.cold.1) at VM.cpp:0:9 [opt]
    frame #15: 0x00000001035e58a4 JavaScriptCore`JSC::VM::drainMicrotasks() [inlined] JSC::MicrotaskQueue::dequeue(this=<unavailable>) at VM.cpp:0:9 [opt]
    frame #16: 0x00000001035e5894 JavaScriptCore`JSC::VM::drainMicrotasks(this=0x000000012f000000) at VM.cpp:1255:46 [opt]
    ...

* Source/JavaScriptCore/interpreter/CallFrame.cpp:
(JSC::CallFrame::dump const):

Canonical link: https://commits.webkit.org/259262@main
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