michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jit_BaselineFrame_h
michael@0: #define jit_BaselineFrame_h
michael@0: 
michael@0: #ifdef JS_ION
michael@0: 
michael@0: #include "jit/IonFrames.h"
michael@0: #include "vm/Stack.h"
michael@0: 
michael@0: namespace js {
michael@0: namespace jit {
michael@0: 
michael@0: struct BaselineDebugModeOSRInfo;
michael@0: 
michael@0: // The stack looks like this, fp is the frame pointer:
michael@0: //
michael@0: // fp+y   arguments
michael@0: // fp+x   IonJSFrameLayout (frame header)
michael@0: // fp  => saved frame pointer
michael@0: // fp-x   BaselineFrame
michael@0: //        locals
michael@0: //        stack values
michael@0: 
michael@0: // Eval frames
michael@0: //
michael@0: // Like js::InterpreterFrame, every BaselineFrame is either a global frame
michael@0: // or a function frame. Both global and function frames can optionally
michael@0: // be "eval frames". The callee token for eval function frames is the
michael@0: // enclosing function. BaselineFrame::evalScript_ stores the eval script
michael@0: // itself.
michael@0: class BaselineFrame
michael@0: {
michael@0:   public:
michael@0:     enum Flags {
michael@0:         // The frame has a valid return value. See also InterpreterFrame::HAS_RVAL.
michael@0:         HAS_RVAL         = 1 << 0,
michael@0: 
michael@0:         // A call object has been pushed on the scope chain.
michael@0:         HAS_CALL_OBJ     = 1 << 2,
michael@0: 
michael@0:         // Frame has an arguments object, argsObj_.
michael@0:         HAS_ARGS_OBJ     = 1 << 4,
michael@0: 
michael@0:         // See InterpreterFrame::PREV_UP_TO_DATE.
michael@0:         PREV_UP_TO_DATE  = 1 << 5,
michael@0: 
michael@0:         // Eval frame, see the "eval frames" comment.
michael@0:         EVAL             = 1 << 6,
michael@0: 
michael@0:         // Frame has hookData_ set.
michael@0:         HAS_HOOK_DATA    = 1 << 7,
michael@0: 
michael@0:         // Frame has profiler entry pushed.
michael@0:         HAS_PUSHED_SPS_FRAME = 1 << 8,
michael@0: 
michael@0:         // Frame has over-recursed on an early check.
michael@0:         OVER_RECURSED    = 1 << 9,
michael@0: 
michael@0:         // Frame has a BaselineRecompileInfo stashed in the scratch value
michael@0:         // slot. See PatchBaselineFramesForDebugMOde.
michael@0:         HAS_DEBUG_MODE_OSR_INFO = 1 << 10
michael@0:     };
michael@0: 
michael@0:   protected: // Silence Clang warning about unused private fields.
michael@0:     // We need to split the Value into 2 fields of 32 bits, otherwise the C++
michael@0:     // compiler may add some padding between the fields.
michael@0:     uint32_t loScratchValue_;
michael@0:     uint32_t hiScratchValue_;
michael@0:     uint32_t loReturnValue_;        // If HAS_RVAL, the frame's return value.
michael@0:     uint32_t hiReturnValue_;
michael@0:     uint32_t frameSize_;
michael@0:     JSObject *scopeChain_;          // Scope chain (always initialized).
michael@0:     JSScript *evalScript_;          // If isEvalFrame(), the current eval script.
michael@0:     ArgumentsObject *argsObj_;      // If HAS_ARGS_OBJ, the arguments object.
michael@0:     void *hookData_;                // If HAS_HOOK_DATA, debugger call hook data.
michael@0:     uint32_t flags_;
michael@0: #if JS_BITS_PER_WORD == 32
michael@0:     uint32_t padding_;              // Pad to 8-byte alignment.
michael@0: #endif
michael@0: 
michael@0:   public:
michael@0:     // Distance between the frame pointer and the frame header (return address).
michael@0:     // This is the old frame pointer saved in the prologue.
michael@0:     static const uint32_t FramePointerOffset = sizeof(void *);
michael@0: 
michael@0:     bool initForOsr(InterpreterFrame *fp, uint32_t numStackValues);
michael@0: 
michael@0:     uint32_t frameSize() const {
michael@0:         return frameSize_;
michael@0:     }
michael@0:     void setFrameSize(uint32_t frameSize) {
michael@0:         frameSize_ = frameSize;
michael@0:     }
michael@0:     inline uint32_t *addressOfFrameSize() {
michael@0:         return &frameSize_;
michael@0:     }
michael@0:     JSObject *scopeChain() const {
michael@0:         return scopeChain_;
michael@0:     }
michael@0:     void setScopeChain(JSObject *scopeChain) {
michael@0:         scopeChain_ = scopeChain;
michael@0:     }
michael@0:     inline JSObject **addressOfScopeChain() {
michael@0:         return &scopeChain_;
michael@0:     }
michael@0: 
michael@0:     inline Value *addressOfScratchValue() {
michael@0:         return reinterpret_cast<Value *>(&loScratchValue_);
michael@0:     }
michael@0: 
michael@0:     inline void pushOnScopeChain(ScopeObject &scope);
michael@0:     inline void popOffScopeChain();
michael@0: 
michael@0:     inline void popWith(JSContext *cx);
michael@0: 
michael@0:     CalleeToken calleeToken() const {
michael@0:         uint8_t *pointer = (uint8_t *)this + Size() + offsetOfCalleeToken();
michael@0:         return *(CalleeToken *)pointer;
michael@0:     }
michael@0:     void replaceCalleeToken(CalleeToken token) {
michael@0:         uint8_t *pointer = (uint8_t *)this + Size() + offsetOfCalleeToken();
michael@0:         *(CalleeToken *)pointer = token;
michael@0:     }
michael@0:     JSScript *script() const {
michael@0:         if (isEvalFrame())
michael@0:             return evalScript();
michael@0:         return ScriptFromCalleeToken(calleeToken());
michael@0:     }
michael@0:     JSFunction *fun() const {
michael@0:         return CalleeTokenToFunction(calleeToken());
michael@0:     }
michael@0:     JSFunction *maybeFun() const {
michael@0:         return isFunctionFrame() ? fun() : nullptr;
michael@0:     }
michael@0:     JSFunction *callee() const {
michael@0:         return CalleeTokenToFunction(calleeToken());
michael@0:     }
michael@0:     Value calleev() const {
michael@0:         return ObjectValue(*callee());
michael@0:     }
michael@0:     size_t numValueSlots() const {
michael@0:         size_t size = frameSize();
michael@0: 
michael@0:         JS_ASSERT(size >= BaselineFrame::FramePointerOffset + BaselineFrame::Size());
michael@0:         size -= BaselineFrame::FramePointerOffset + BaselineFrame::Size();
michael@0: 
michael@0:         JS_ASSERT((size % sizeof(Value)) == 0);
michael@0:         return size / sizeof(Value);
michael@0:     }
michael@0:     Value *valueSlot(size_t slot) const {
michael@0:         JS_ASSERT(slot < numValueSlots());
michael@0:         return (Value *)this - (slot + 1);
michael@0:     }
michael@0: 
michael@0:     Value &unaliasedVar(uint32_t i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const {
michael@0:         JS_ASSERT(i < script()->nfixedvars());
michael@0:         JS_ASSERT_IF(checkAliasing, !script()->varIsAliased(i));
michael@0:         return *valueSlot(i);
michael@0:     }
michael@0: 
michael@0:     Value &unaliasedFormal(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const {
michael@0:         JS_ASSERT(i < numFormalArgs());
michael@0:         JS_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals() &&
michael@0:                                     !script()->formalIsAliased(i));
michael@0:         return argv()[i];
michael@0:     }
michael@0: 
michael@0:     Value &unaliasedActual(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const {
michael@0:         JS_ASSERT(i < numActualArgs());
michael@0:         JS_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals());
michael@0:         JS_ASSERT_IF(checkAliasing && i < numFormalArgs(), !script()->formalIsAliased(i));
michael@0:         return argv()[i];
michael@0:     }
michael@0: 
michael@0:     Value &unaliasedLocal(uint32_t i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) const {
michael@0:         JS_ASSERT(i < script()->nfixed());
michael@0: #ifdef DEBUG
michael@0:         CheckLocalUnaliased(checkAliasing, script(), i);
michael@0: #endif
michael@0:         return *valueSlot(i);
michael@0:     }
michael@0: 
michael@0:     unsigned numActualArgs() const {
michael@0:         return *(size_t *)(reinterpret_cast<const uint8_t *>(this) +
michael@0:                              BaselineFrame::Size() +
michael@0:                              offsetOfNumActualArgs());
michael@0:     }
michael@0:     unsigned numFormalArgs() const {
michael@0:         return script()->functionNonDelazifying()->nargs();
michael@0:     }
michael@0:     Value &thisValue() const {
michael@0:         return *(Value *)(reinterpret_cast<const uint8_t *>(this) +
michael@0:                          BaselineFrame::Size() +
michael@0:                          offsetOfThis());
michael@0:     }
michael@0:     Value *argv() const {
michael@0:         return (Value *)(reinterpret_cast<const uint8_t *>(this) +
michael@0:                          BaselineFrame::Size() +
michael@0:                          offsetOfArg(0));
michael@0:     }
michael@0: 
michael@0:     bool copyRawFrameSlots(AutoValueVector *vec) const;
michael@0: 
michael@0:     bool hasReturnValue() const {
michael@0:         return flags_ & HAS_RVAL;
michael@0:     }
michael@0:     MutableHandleValue returnValue() {
michael@0:         return MutableHandleValue::fromMarkedLocation(reinterpret_cast<Value *>(&loReturnValue_));
michael@0:     }
michael@0:     void setReturnValue(const Value &v) {
michael@0:         flags_ |= HAS_RVAL;
michael@0:         returnValue().set(v);
michael@0:     }
michael@0:     inline Value *addressOfReturnValue() {
michael@0:         return reinterpret_cast<Value *>(&loReturnValue_);
michael@0:     }
michael@0: 
michael@0:     bool hasCallObj() const {
michael@0:         return flags_ & HAS_CALL_OBJ;
michael@0:     }
michael@0: 
michael@0:     inline CallObject &callObj() const;
michael@0: 
michael@0:     void setFlags(uint32_t flags) {
michael@0:         flags_ = flags;
michael@0:     }
michael@0:     uint32_t *addressOfFlags() {
michael@0:         return &flags_;
michael@0:     }
michael@0: 
michael@0:     inline bool pushBlock(JSContext *cx, Handle<StaticBlockObject *> block);
michael@0:     inline void popBlock(JSContext *cx);
michael@0: 
michael@0:     bool strictEvalPrologue(JSContext *cx);
michael@0:     bool heavyweightFunPrologue(JSContext *cx);
michael@0:     bool initFunctionScopeObjects(JSContext *cx);
michael@0: 
michael@0:     void initArgsObjUnchecked(ArgumentsObject &argsobj) {
michael@0:         flags_ |= HAS_ARGS_OBJ;
michael@0:         argsObj_ = &argsobj;
michael@0:     }
michael@0:     void initArgsObj(ArgumentsObject &argsobj) {
michael@0:         JS_ASSERT(script()->needsArgsObj());
michael@0:         initArgsObjUnchecked(argsobj);
michael@0:     }
michael@0:     bool hasArgsObj() const {
michael@0:         return flags_ & HAS_ARGS_OBJ;
michael@0:     }
michael@0:     ArgumentsObject &argsObj() const {
michael@0:         JS_ASSERT(hasArgsObj());
michael@0:         JS_ASSERT(script()->needsArgsObj());
michael@0:         return *argsObj_;
michael@0:     }
michael@0: 
michael@0:     bool prevUpToDate() const {
michael@0:         return flags_ & PREV_UP_TO_DATE;
michael@0:     }
michael@0:     void setPrevUpToDate() {
michael@0:         flags_ |= PREV_UP_TO_DATE;
michael@0:     }
michael@0: 
michael@0:     JSScript *evalScript() const {
michael@0:         JS_ASSERT(isEvalFrame());
michael@0:         return evalScript_;
michael@0:     }
michael@0: 
michael@0:     bool hasHookData() const {
michael@0:         return flags_ & HAS_HOOK_DATA;
michael@0:     }
michael@0: 
michael@0:     void *maybeHookData() const {
michael@0:         return hasHookData() ? hookData_ : nullptr;
michael@0:     }
michael@0: 
michael@0:     void setHookData(void *v) {
michael@0:         hookData_ = v;
michael@0:         flags_ |= HAS_HOOK_DATA;
michael@0:     }
michael@0: 
michael@0:     bool hasPushedSPSFrame() const {
michael@0:         return flags_ & HAS_PUSHED_SPS_FRAME;
michael@0:     }
michael@0: 
michael@0:     void setPushedSPSFrame() {
michael@0:         flags_ |= HAS_PUSHED_SPS_FRAME;
michael@0:     }
michael@0: 
michael@0:     void unsetPushedSPSFrame() {
michael@0:         flags_ &= ~HAS_PUSHED_SPS_FRAME;
michael@0:     }
michael@0: 
michael@0:     bool overRecursed() const {
michael@0:         return flags_ & OVER_RECURSED;
michael@0:     }
michael@0: 
michael@0:     void setOverRecursed() {
michael@0:         flags_ |= OVER_RECURSED;
michael@0:     }
michael@0: 
michael@0:     BaselineDebugModeOSRInfo *debugModeOSRInfo() {
michael@0:         MOZ_ASSERT(flags_ & HAS_DEBUG_MODE_OSR_INFO);
michael@0:         return *reinterpret_cast<BaselineDebugModeOSRInfo **>(&loScratchValue_);
michael@0:     }
michael@0: 
michael@0:     BaselineDebugModeOSRInfo *getDebugModeOSRInfo() {
michael@0:         if (flags_ & HAS_DEBUG_MODE_OSR_INFO)
michael@0:             return debugModeOSRInfo();
michael@0:         return nullptr;
michael@0:     }
michael@0: 
michael@0:     void setDebugModeOSRInfo(BaselineDebugModeOSRInfo *info) {
michael@0:         flags_ |= HAS_DEBUG_MODE_OSR_INFO;
michael@0:         *reinterpret_cast<BaselineDebugModeOSRInfo **>(&loScratchValue_) = info;
michael@0:     }
michael@0: 
michael@0:     void deleteDebugModeOSRInfo();
michael@0: 
michael@0:     void trace(JSTracer *trc, JitFrameIterator &frame);
michael@0: 
michael@0:     bool isFunctionFrame() const {
michael@0:         return CalleeTokenIsFunction(calleeToken());
michael@0:     }
michael@0:     bool isGlobalFrame() const {
michael@0:         return !CalleeTokenIsFunction(calleeToken());
michael@0:     }
michael@0:      bool isEvalFrame() const {
michael@0:         return flags_ & EVAL;
michael@0:     }
michael@0:     bool isStrictEvalFrame() const {
michael@0:         return isEvalFrame() && script()->strict();
michael@0:     }
michael@0:     bool isNonStrictEvalFrame() const {
michael@0:         return isEvalFrame() && !script()->strict();
michael@0:     }
michael@0:     bool isDirectEvalFrame() const {
michael@0:         return isEvalFrame() && script()->staticLevel() > 0;
michael@0:     }
michael@0:     bool isNonStrictDirectEvalFrame() const {
michael@0:         return isNonStrictEvalFrame() && isDirectEvalFrame();
michael@0:     }
michael@0:     bool isNonEvalFunctionFrame() const {
michael@0:         return isFunctionFrame() && !isEvalFrame();
michael@0:     }
michael@0:     bool isDebuggerFrame() const {
michael@0:         return false;
michael@0:     }
michael@0:     bool isGeneratorFrame() const {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     IonJSFrameLayout *framePrefix() const {
michael@0:         uint8_t *fp = (uint8_t *)this + Size() + FramePointerOffset;
michael@0:         return (IonJSFrameLayout *)fp;
michael@0:     }
michael@0: 
michael@0:     // Methods below are used by the compiler.
michael@0:     static size_t offsetOfCalleeToken() {
michael@0:         return FramePointerOffset + js::jit::IonJSFrameLayout::offsetOfCalleeToken();
michael@0:     }
michael@0:     static size_t offsetOfThis() {
michael@0:         return FramePointerOffset + js::jit::IonJSFrameLayout::offsetOfThis();
michael@0:     }
michael@0:     static size_t offsetOfArg(size_t index) {
michael@0:         return FramePointerOffset + js::jit::IonJSFrameLayout::offsetOfActualArg(index);
michael@0:     }
michael@0:     static size_t offsetOfNumActualArgs() {
michael@0:         return FramePointerOffset + js::jit::IonJSFrameLayout::offsetOfNumActualArgs();
michael@0:     }
michael@0:     static size_t Size() {
michael@0:         return sizeof(BaselineFrame);
michael@0:     }
michael@0: 
michael@0:     // The reverseOffsetOf methods below compute the offset relative to the
michael@0:     // frame's base pointer. Since the stack grows down, these offsets are
michael@0:     // negative.
michael@0:     static int reverseOffsetOfFrameSize() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, frameSize_);
michael@0:     }
michael@0:     static int reverseOffsetOfScratchValue() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, loScratchValue_);
michael@0:     }
michael@0:     static int reverseOffsetOfScopeChain() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, scopeChain_);
michael@0:     }
michael@0:     static int reverseOffsetOfArgsObj() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, argsObj_);
michael@0:     }
michael@0:     static int reverseOffsetOfFlags() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, flags_);
michael@0:     }
michael@0:     static int reverseOffsetOfEvalScript() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, evalScript_);
michael@0:     }
michael@0:     static int reverseOffsetOfReturnValue() {
michael@0:         return -int(Size()) + offsetof(BaselineFrame, loReturnValue_);
michael@0:     }
michael@0:     static int reverseOffsetOfLocal(size_t index) {
michael@0:         return -int(Size()) - (index + 1) * sizeof(Value);
michael@0:     }
michael@0: };
michael@0: 
michael@0: // Ensure the frame is 8-byte aligned (required on ARM).
michael@0: JS_STATIC_ASSERT(((sizeof(BaselineFrame) + BaselineFrame::FramePointerOffset) % 8) == 0);
michael@0: 
michael@0: } // namespace jit
michael@0: } // namespace js
michael@0: 
michael@0: #endif // JS_ION
michael@0: 
michael@0: #endif /* jit_BaselineFrame_h */