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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
commit | 43a97878ce14b72f0981164f87f2e35e14151312 (patch) | |
tree | 620249daf56c0258faa40cbdcf9cfba06de2a846 /js/src/jit/BaselineFrame.h | |
parent | Initial commit. (diff) | |
download | firefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip |
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'js/src/jit/BaselineFrame.h')
-rw-r--r-- | js/src/jit/BaselineFrame.h | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/js/src/jit/BaselineFrame.h b/js/src/jit/BaselineFrame.h new file mode 100644 index 0000000000..6614d23e15 --- /dev/null +++ b/js/src/jit/BaselineFrame.h @@ -0,0 +1,373 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef jit_BaselineFrame_h +#define jit_BaselineFrame_h + +#include <algorithm> + +#include "jit/CalleeToken.h" +#include "jit/JitFrames.h" +#include "jit/ScriptFromCalleeToken.h" +#include "vm/Stack.h" + +namespace js { +namespace jit { + +class ICEntry; +class ICScript; +class JSJitFrameIter; + +// The stack looks like this, fp is the frame pointer: +// +// fp+y arguments +// fp => JitFrameLayout (frame header) +// fp-x BaselineFrame +// locals +// stack values + +class BaselineFrame { + public: + enum Flags : uint32_t { + // The frame has a valid return value. See also InterpreterFrame::HAS_RVAL. + HAS_RVAL = 1 << 0, + + // The frame is running in the Baseline interpreter instead of JIT. + RUNNING_IN_INTERPRETER = 1 << 1, + + // An initial environment has been pushed on the environment chain for + // function frames that need a CallObject or eval frames that need a + // VarEnvironmentObject. + HAS_INITIAL_ENV = 1 << 2, + + // Frame has an arguments object, argsObj_. + HAS_ARGS_OBJ = 1 << 4, + + // See InterpreterFrame::PREV_UP_TO_DATE. + PREV_UP_TO_DATE = 1 << 5, + + // Frame has execution observed by a Debugger. + // + // See comment above 'isDebuggee' in vm/Realm.h for explanation + // of invariants of debuggee compartments, scripts, and frames. + DEBUGGEE = 1 << 6, + }; + + protected: // Silence Clang warning about unused private fields. + // The fields below are only valid if RUNNING_IN_INTERPRETER. + JSScript* interpreterScript_; + jsbytecode* interpreterPC_; + ICEntry* interpreterICEntry_; + + JSObject* envChain_; // Environment chain (always initialized). + ICScript* icScript_; // IC script (initialized if Warp is enabled). + ArgumentsObject* argsObj_; // If HAS_ARGS_OBJ, the arguments object. + + // We need to split the Value into 2 fields of 32 bits, otherwise the C++ + // compiler may add some padding between the fields. + uint32_t loScratchValue_; + uint32_t hiScratchValue_; + uint32_t flags_; +#ifdef DEBUG + // Size of the frame. Stored in DEBUG builds when calling into C++. This is + // BaselineFrame::Size() + the size of the local and expression stack Values. + // + // We don't store this in release builds because it's redundant with the frame + // size computed from the frame pointers. In debug builds it's still useful + // for assertions. + uint32_t debugFrameSize_; +#else + uint32_t unused_; +#endif + uint32_t loReturnValue_; // If HAS_RVAL, the frame's return value. + uint32_t hiReturnValue_; + + public: + [[nodiscard]] bool initForOsr(InterpreterFrame* fp, uint32_t numStackValues); + +#ifdef DEBUG + uint32_t debugFrameSize() const { return debugFrameSize_; } + void setDebugFrameSize(uint32_t frameSize) { debugFrameSize_ = frameSize; } +#endif + + JSObject* environmentChain() const { return envChain_; } + void setEnvironmentChain(JSObject* envChain) { envChain_ = envChain; } + + template <typename SpecificEnvironment> + inline void pushOnEnvironmentChain(SpecificEnvironment& env); + template <typename SpecificEnvironment> + inline void popOffEnvironmentChain(); + inline void replaceInnermostEnvironment(EnvironmentObject& env); + + CalleeToken calleeToken() const { return framePrefix()->calleeToken(); } + void replaceCalleeToken(CalleeToken token) { + framePrefix()->replaceCalleeToken(token); + } + bool isConstructing() const { + return CalleeTokenIsConstructing(calleeToken()); + } + JSScript* script() const { return ScriptFromCalleeToken(calleeToken()); } + JSFunction* callee() const { return CalleeTokenToFunction(calleeToken()); } + Value calleev() const { return ObjectValue(*callee()); } + + size_t numValueSlots(size_t frameSize) const { + MOZ_ASSERT(frameSize == debugFrameSize()); + + MOZ_ASSERT(frameSize >= BaselineFrame::Size()); + frameSize -= BaselineFrame::Size(); + + MOZ_ASSERT((frameSize % sizeof(Value)) == 0); + return frameSize / sizeof(Value); + } + +#ifdef DEBUG + size_t debugNumValueSlots() const { return numValueSlots(debugFrameSize()); } +#endif + + Value* valueSlot(size_t slot) const { + MOZ_ASSERT(slot < debugNumValueSlots()); + return (Value*)this - (slot + 1); + } + + static size_t frameSizeForNumValueSlots(size_t numValueSlots) { + return BaselineFrame::Size() + numValueSlots * sizeof(Value); + } + + Value& unaliasedFormal( + unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const { + MOZ_ASSERT(i < numFormalArgs()); + MOZ_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals() && + !script()->formalIsAliased(i)); + return argv()[i]; + } + + Value& unaliasedActual( + unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const { + MOZ_ASSERT(i < numActualArgs()); + MOZ_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals()); + MOZ_ASSERT_IF(checkAliasing && i < numFormalArgs(), + !script()->formalIsAliased(i)); + return argv()[i]; + } + + Value& unaliasedLocal(uint32_t i) const { + MOZ_ASSERT(i < script()->nfixed()); + return *valueSlot(i); + } + + unsigned numActualArgs() const { return framePrefix()->numActualArgs(); } + unsigned numFormalArgs() const { return script()->function()->nargs(); } + Value& thisArgument() const { + MOZ_ASSERT(isFunctionFrame()); + return framePrefix()->thisv(); + } + Value* argv() const { return framePrefix()->actualArgs(); } + + [[nodiscard]] bool saveGeneratorSlots(JSContext* cx, unsigned nslots, + ArrayObject* dest) const; + + public: + void prepareForBaselineInterpreterToJitOSR() { + // Clearing the RUNNING_IN_INTERPRETER flag is sufficient, but we also null + // out the interpreter fields to ensure we don't use stale values. + flags_ &= ~RUNNING_IN_INTERPRETER; + interpreterScript_ = nullptr; + interpreterPC_ = nullptr; + } + + private: + bool uninlineIsProfilerSamplingEnabled(JSContext* cx); + + public: + // Switch a JIT frame on the stack to Interpreter mode. The caller is + // responsible for patching the return address into this frame to a location + // in the interpreter code. Also assert profiler sampling has been suppressed + // so the sampler thread doesn't see an inconsistent state while we are + // patching frames. + void switchFromJitToInterpreter(JSContext* cx, jsbytecode* pc) { + MOZ_ASSERT(!uninlineIsProfilerSamplingEnabled(cx)); + MOZ_ASSERT(!runningInInterpreter()); + flags_ |= RUNNING_IN_INTERPRETER; + setInterpreterFields(pc); + } + void switchFromJitToInterpreterAtPrologue(JSContext* cx) { + MOZ_ASSERT(!uninlineIsProfilerSamplingEnabled(cx)); + MOZ_ASSERT(!runningInInterpreter()); + flags_ |= RUNNING_IN_INTERPRETER; + setInterpreterFieldsForPrologue(script()); + } + + // Like switchFromJitToInterpreter, but set the interpreterICEntry_ field to + // nullptr. Initializing this field requires a binary search on the + // JitScript's ICEntry list but the exception handler never returns to this + // pc anyway so we can avoid the overhead. + void switchFromJitToInterpreterForExceptionHandler(JSContext* cx, + jsbytecode* pc) { + MOZ_ASSERT(!uninlineIsProfilerSamplingEnabled(cx)); + MOZ_ASSERT(!runningInInterpreter()); + flags_ |= RUNNING_IN_INTERPRETER; + interpreterScript_ = script(); + interpreterPC_ = pc; + interpreterICEntry_ = nullptr; + } + + bool runningInInterpreter() const { return flags_ & RUNNING_IN_INTERPRETER; } + + JSScript* interpreterScript() const { + MOZ_ASSERT(runningInInterpreter()); + return interpreterScript_; + } + + jsbytecode* interpreterPC() const { + MOZ_ASSERT(runningInInterpreter()); + return interpreterPC_; + } + + void setInterpreterFields(JSScript* script, jsbytecode* pc); + + void setInterpreterFields(jsbytecode* pc) { + setInterpreterFields(script(), pc); + } + + // Initialize interpreter fields for resuming in the prologue (before the + // argument type check ICs). + void setInterpreterFieldsForPrologue(JSScript* script); + + ICScript* icScript() const { return icScript_; } + void setICScript(ICScript* icScript) { icScript_ = icScript; } + + // The script that owns the current ICScript. + JSScript* outerScript() const; + + bool hasReturnValue() const { return flags_ & HAS_RVAL; } + MutableHandleValue returnValue() { + if (!hasReturnValue()) { + addressOfReturnValue()->setUndefined(); + } + return MutableHandleValue::fromMarkedLocation(addressOfReturnValue()); + } + void setReturnValue(const Value& v) { + returnValue().set(v); + flags_ |= HAS_RVAL; + } + inline Value* addressOfReturnValue() { + return reinterpret_cast<Value*>(&loReturnValue_); + } + + bool hasInitialEnvironment() const { return flags_ & HAS_INITIAL_ENV; } + + inline CallObject& callObj() const; + + void setFlags(uint32_t flags) { flags_ = flags; } + + [[nodiscard]] inline bool pushLexicalEnvironment(JSContext* cx, + Handle<LexicalScope*> scope); + [[nodiscard]] inline bool freshenLexicalEnvironment(JSContext* cx); + [[nodiscard]] inline bool recreateLexicalEnvironment(JSContext* cx); + + [[nodiscard]] bool initFunctionEnvironmentObjects(JSContext* cx); + [[nodiscard]] bool pushClassBodyEnvironment(JSContext* cx, + Handle<ClassBodyScope*> scope); + [[nodiscard]] bool pushVarEnvironment(JSContext* cx, Handle<Scope*> scope); + + void initArgsObjUnchecked(ArgumentsObject& argsobj) { + flags_ |= HAS_ARGS_OBJ; + argsObj_ = &argsobj; + } + void initArgsObj(ArgumentsObject& argsobj) { + MOZ_ASSERT(script()->needsArgsObj()); + initArgsObjUnchecked(argsobj); + } + bool hasArgsObj() const { return flags_ & HAS_ARGS_OBJ; } + ArgumentsObject& argsObj() const { + MOZ_ASSERT(hasArgsObj()); + MOZ_ASSERT(script()->needsArgsObj()); + return *argsObj_; + } + + bool prevUpToDate() const { return flags_ & PREV_UP_TO_DATE; } + void setPrevUpToDate() { flags_ |= PREV_UP_TO_DATE; } + void unsetPrevUpToDate() { flags_ &= ~PREV_UP_TO_DATE; } + + bool isDebuggee() const { return flags_ & DEBUGGEE; } + void setIsDebuggee() { flags_ |= DEBUGGEE; } + inline void unsetIsDebuggee(); + + void trace(JSTracer* trc, const JSJitFrameIter& frame); + + bool isGlobalFrame() const { return script()->isGlobalCode(); } + bool isModuleFrame() const { return script()->isModule(); } + bool isEvalFrame() const { return script()->isForEval(); } + bool isFunctionFrame() const { + return CalleeTokenIsFunction(calleeToken()) && !isModuleFrame(); + } + bool isDebuggerEvalFrame() const { return false; } + + JitFrameLayout* framePrefix() const { + uint8_t* fp = (uint8_t*)this + Size(); + return (JitFrameLayout*)fp; + } + + static size_t Size() { return sizeof(BaselineFrame); } + + // The reverseOffsetOf methods below compute the offset relative to the + // frame's base pointer. Since the stack grows down, these offsets are + // negative. + +#ifdef DEBUG + static int reverseOffsetOfDebugFrameSize() { + return -int(Size()) + offsetof(BaselineFrame, debugFrameSize_); + } +#endif + + // The scratch value slot can either be used as a Value slot or as two + // separate 32-bit integer slots. + static int reverseOffsetOfScratchValueLow32() { + return -int(Size()) + offsetof(BaselineFrame, loScratchValue_); + } + static int reverseOffsetOfScratchValueHigh32() { + return -int(Size()) + offsetof(BaselineFrame, hiScratchValue_); + } + static int reverseOffsetOfScratchValue() { + return reverseOffsetOfScratchValueLow32(); + } + + static int reverseOffsetOfEnvironmentChain() { + return -int(Size()) + offsetof(BaselineFrame, envChain_); + } + static int reverseOffsetOfArgsObj() { + return -int(Size()) + offsetof(BaselineFrame, argsObj_); + } + static int reverseOffsetOfFlags() { + return -int(Size()) + offsetof(BaselineFrame, flags_); + } + static int reverseOffsetOfReturnValue() { + return -int(Size()) + offsetof(BaselineFrame, loReturnValue_); + } + static int reverseOffsetOfInterpreterScript() { + return -int(Size()) + offsetof(BaselineFrame, interpreterScript_); + } + static int reverseOffsetOfInterpreterPC() { + return -int(Size()) + offsetof(BaselineFrame, interpreterPC_); + } + static int reverseOffsetOfInterpreterICEntry() { + return -int(Size()) + offsetof(BaselineFrame, interpreterICEntry_); + } + static int reverseOffsetOfICScript() { + return -int(Size()) + offsetof(BaselineFrame, icScript_); + } + static int reverseOffsetOfLocal(size_t index) { + return -int(Size()) - (index + 1) * sizeof(Value); + } +}; + +// Ensure the frame is 8-byte aligned (required on ARM). +static_assert((sizeof(BaselineFrame) % 8) == 0, "frame must be 8-byte aligned"); + +} // namespace jit +} // namespace js + +#endif /* jit_BaselineFrame_h */ |