Move microtask queue to JS - #6
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This uses `TypedArray.prototype.set` when `TypedArray.from(array)` receives another TypedArray It does not handle when `set` has been overridden. This will likely have to be changed later, but it is better than the present state
Instead of checking `isJSCall` three times, now it checks once.
Instead of 4 checks, only do one
This makes promises & async take two ticks instead of three ticks. See tc39/ecma262#1250 See tc39/ecma262#2770 See tc39/ecma262#2772 50% faster when measuring call overhead. Similar improvements for https://github.com/v8/promise-performance-tests and when measuring with the following snippet: ```js import { run, bench } from "mitata"; bench("sync", () => {}); bench("async", async () => {}); run(); ```
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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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https://bugs.webkit.org/show_bug.cgi?id=281902 rdar://136486349 Reviewed by Mike Wyrzykowski. Metal: Ensure potentially infinite loops have defined behavior The MSL compiler would omit infinite loops and assume number domains based on the omission logic. This would induce incorrect number domains in case the infinite loops would be invokable. Infinite loops are undefined in C++ and thus in MSL. It is the job of the programmer to ensure undefined behavior cannot happen. Consider GLSL loop like: uniform float i; ... if (i != 0.5) for(;;) { } gl_FragColor = vec4(i); Historically this would emit MSL loop in spirit of: if (i != 0.5) { bool c = true; while (c) { } } ANGLE_fragmentOut.gl_FragColor = metal::float4(i, i, i, i); Since This could cause the MSL compiler to optimize the function to equivalent of: ANGLE_fragmentOut.gl_FragColor = metal::float4(0.5, 0.5, 0.5, 0.5); Presumably this loop omission would happen at the clang frontend part. Before, was worked around by emitting asm statements to the MSL: bool c = true; while (c) { __asm__(""); } The asm injection would would work for this particular source pattern, presumably because injecting the asm would avoid the loop omission at the clang frontend part. The MSL/C++ code is still UB, though. The asm statement does not cause anything that C++ would consider as "forward progress" of the loop. The success was just due to how the backend worked. The bitcode produced would be similar to: 4: tail call void asm sideeffect "", ""() #6, !srcloc !28 br label %4, !llvm.loop !29 Here, the compiler can be seen to simply fail to detect a loop that does not make forward progress. Considering GLSL of form: uniform int f; ... for (;;) { if (f <= 1) break; } With asm injection to the loop, this would produce: 5: tail call void asm sideeffect "", ""() #8, !srcloc !29 %6 = load i32, i32 addrspace(2)* %4, align 4, !tbaa !30 %7 = icmp slt i32 %6, 2 br i1 %7, label %8, label %5 8: This code is still assumed to make progress. The backend optimizer is free to assume that the condition holds, since the load to break the loop is from constant address space. I.e. uniform f does not change its value during the loop. Instead of injecting asm, inject a read of unused volatile variable. The volatile variable access is defined in C++ as forward progress. This means infinite loop containing such read is considered defined. To simplify the implementation and to avoid volatile writes, the read is to a dummy variable instead of the loop condition bool. The tests here do not pass completely for MSL backend. In case the compiler would omit the infinite loop (unpatched code), they would fail with demonstration of how the values behave. After fixing, the loops cause timeout but Metal backend does not have implementation to report context loss. Also, the ReadPixels is just for demostration purposes of the unpatched code. * Source/ThirdParty/ANGLE/src/compiler/translator/msl/EmitMetal.cpp: (GenMetalTraverser::GenMetalTraverser): (GenMetalTraverser::emitLoopBody): (GenMetalTraverser::emitForwardProgressStore): (GenMetalTraverser::emitForwardProgressSignal): (GenMetalTraverser::visitForLoop): (GenMetalTraverser::visitWhileLoop): (GenMetalTraverser::visitDoWhileLoop): * Source/ThirdParty/ANGLE/src/tests/angle_end2end_tests.gni: * Source/ThirdParty/ANGLE/src/tests/gl_tests/TimeoutDrawTest.cpp: Added. (angle::TimeoutDrawTest::TimeoutDrawTest): (angle::TEST_P): Originally-landed-as: 283286.350@safari-7620-branch (b82d94e). rdar://141318430 Canonical link: https://commits.webkit.org/288020@main
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