Add m-esr52 at 52.6.0

1 files changed, 458 insertions, 0 deletions

diff --git a/js/src/jit/BaselineFrame.h b/js/src/jit/BaselineFrame.h
new file mode 100644
index 000000000..9a30cdcfc
--- /dev/null
+++ b/js/src/jit/BaselineFrame.h
@@ -0,0 +1,458 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * 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 "jit/JitFrames.h"
+#include "vm/Stack.h"
+
+namespace js {
+namespace jit {
+
+struct BaselineDebugModeOSRInfo;
+
+// The stack looks like this, fp is the frame pointer:
+//
+// fp+y   arguments
+// fp+x   JitFrameLayout (frame header)
+// fp  => saved frame pointer
+// 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,
+
+        // 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 jscompartment.h for explanation of
+        // invariants of debuggee compartments, scripts, and frames.
+        DEBUGGEE         = 1 << 6,
+
+        // (1 << 7 and 1 << 8 are unused)
+
+        // Frame has over-recursed on an early check.
+        OVER_RECURSED    = 1 << 9,
+
+        // Frame has a BaselineRecompileInfo stashed in the scratch value
+        // slot. See PatchBaselineFramesForDebugMode.
+        HAS_DEBUG_MODE_OSR_INFO = 1 << 10,
+
+        // This flag is intended for use whenever the frame is settled on a
+        // native code address without a corresponding ICEntry. In this case,
+        // the frame contains an explicit bytecode offset for frame iterators.
+        //
+        // There can also be an override pc if the frame has had its
+        // environment chain unwound to a pc during exception handling that is
+        // different from its current pc.
+        //
+        // This flag should never be set when we're executing JIT code.
+        HAS_OVERRIDE_PC = 1 << 11,
+
+        // If set, we're handling an exception for this frame. This is set for
+        // debug mode OSR sanity checking when it handles corner cases which
+        // only arise during exception handling.
+        HANDLING_EXCEPTION = 1 << 12,
+
+        // If set, this frame has been on the stack when
+        // |js::SavedStacks::saveCurrentStack| was called, and so there is a
+        // |js::SavedFrame| object cached for this frame.
+        HAS_CACHED_SAVED_FRAME = 1 << 13
+    };
+
+  protected: // Silence Clang warning about unused private fields.
+    // We need to split the Value into 2 fields of 32 bits, otherwise the C++
+    // compiler may add some padding between the fields.
+
+    union {
+        struct {
+            uint32_t loScratchValue_;
+            uint32_t hiScratchValue_;
+        };
+        BaselineDebugModeOSRInfo* debugModeOSRInfo_;
+    };
+    uint32_t loReturnValue_;              // If HAS_RVAL, the frame's return value.
+    uint32_t hiReturnValue_;
+    uint32_t frameSize_;
+    JSObject* envChain_;                  // Environment chain (always initialized).
+    ArgumentsObject* argsObj_;            // If HAS_ARGS_OBJ, the arguments object.
+    uint32_t overrideOffset_;             // If HAS_OVERRIDE_PC, the bytecode offset.
+    uint32_t flags_;
+
+  public:
+    // Distance between the frame pointer and the frame header (return address).
+    // This is the old frame pointer saved in the prologue.
+    static const uint32_t FramePointerOffset = sizeof(void*);
+
+    MOZ_MUST_USE bool initForOsr(InterpreterFrame* fp, uint32_t numStackValues);
+
+    uint32_t frameSize() const {
+        return frameSize_;
+    }
+    void setFrameSize(uint32_t frameSize) {
+        frameSize_ = frameSize;
+    }
+    inline uint32_t* addressOfFrameSize() {
+        return &frameSize_;
+    }
+    JSObject* environmentChain() const {
+        return envChain_;
+    }
+    void setEnvironmentChain(JSObject* envChain) {
+        envChain_ = envChain;
+    }
+    inline JSObject** addressOfEnvironmentChain() {
+        return &envChain_;
+    }
+
+    inline Value* addressOfScratchValue() {
+        return reinterpret_cast<Value*>(&loScratchValue_);
+    }
+
+    template <typename SpecificEnvironment>
+    inline void pushOnEnvironmentChain(SpecificEnvironment& env);
+    template <typename SpecificEnvironment>
+    inline void popOffEnvironmentChain();
+    inline void replaceInnermostEnvironment(EnvironmentObject& env);
+
+    CalleeToken calleeToken() const {
+        uint8_t* pointer = (uint8_t*)this + Size() + offsetOfCalleeToken();
+        return *(CalleeToken*)pointer;
+    }
+    void replaceCalleeToken(CalleeToken token) {
+        uint8_t* pointer = (uint8_t*)this + Size() + offsetOfCalleeToken();
+        *(CalleeToken*)pointer = 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() const {
+        size_t size = frameSize();
+
+        MOZ_ASSERT(size >= BaselineFrame::FramePointerOffset + BaselineFrame::Size());
+        size -= BaselineFrame::FramePointerOffset + BaselineFrame::Size();
+
+        MOZ_ASSERT((size % sizeof(Value)) == 0);
+        return size / sizeof(Value);
+    }
+    Value* valueSlot(size_t slot) const {
+        MOZ_ASSERT(slot < numValueSlots());
+        return (Value*)this - (slot + 1);
+    }
+
+    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 *(size_t*)(reinterpret_cast<const uint8_t*>(this) +
+                             BaselineFrame::Size() +
+                             offsetOfNumActualArgs());
+    }
+    unsigned numFormalArgs() const {
+        return script()->functionNonDelazifying()->nargs();
+    }
+    Value& thisArgument() const {
+        MOZ_ASSERT(isFunctionFrame());
+        return *(Value*)(reinterpret_cast<const uint8_t*>(this) +
+                         BaselineFrame::Size() +
+                         offsetOfThis());
+    }
+    Value* argv() const {
+        return (Value*)(reinterpret_cast<const uint8_t*>(this) +
+                         BaselineFrame::Size() +
+                         offsetOfArg(0));
+    }
+
+  private:
+    Value* evalNewTargetAddress() const {
+        MOZ_ASSERT(isEvalFrame());
+        MOZ_ASSERT(script()->isDirectEvalInFunction());
+        return (Value*)(reinterpret_cast<const uint8_t*>(this) +
+                        BaselineFrame::Size() +
+                        offsetOfEvalNewTarget());
+    }
+
+  public:
+    Value newTarget() const {
+        if (isEvalFrame())
+            return *evalNewTargetAddress();
+        MOZ_ASSERT(isFunctionFrame());
+        if (callee()->isArrow())
+            return callee()->getExtendedSlot(FunctionExtended::ARROW_NEWTARGET_SLOT);
+        if (isConstructing()) {
+            return *(Value*)(reinterpret_cast<const uint8_t*>(this) +
+                             BaselineFrame::Size() +
+                             offsetOfArg(Max(numFormalArgs(), numActualArgs())));
+        }
+        return UndefinedValue();
+    }
+
+    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;
+    }
+    uint32_t* addressOfFlags() {
+        return &flags_;
+    }
+
+    inline MOZ_MUST_USE bool pushLexicalEnvironment(JSContext* cx, Handle<LexicalScope*> scope);
+    inline MOZ_MUST_USE bool freshenLexicalEnvironment(JSContext* cx);
+    inline MOZ_MUST_USE bool recreateLexicalEnvironment(JSContext* cx);
+
+    MOZ_MUST_USE bool initFunctionEnvironmentObjects(JSContext* cx);
+    MOZ_MUST_USE bool pushVarEnvironment(JSContext* cx, HandleScope 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();
+
+    bool isHandlingException() const {
+        return flags_ & HANDLING_EXCEPTION;
+    }
+    void setIsHandlingException() {
+        flags_ |= HANDLING_EXCEPTION;
+    }
+    void unsetIsHandlingException() {
+        flags_ &= ~HANDLING_EXCEPTION;
+    }
+
+    bool hasCachedSavedFrame() const {
+        return flags_ & HAS_CACHED_SAVED_FRAME;
+    }
+    void setHasCachedSavedFrame() {
+        flags_ |= HAS_CACHED_SAVED_FRAME;
+    }
+
+    bool overRecursed() const {
+        return flags_ & OVER_RECURSED;
+    }
+
+    void setOverRecursed() {
+        flags_ |= OVER_RECURSED;
+    }
+
+    BaselineDebugModeOSRInfo* debugModeOSRInfo() {
+        MOZ_ASSERT(flags_ & HAS_DEBUG_MODE_OSR_INFO);
+        return debugModeOSRInfo_;
+    }
+
+    BaselineDebugModeOSRInfo* getDebugModeOSRInfo() {
+        if (flags_ & HAS_DEBUG_MODE_OSR_INFO)
+            return debugModeOSRInfo();
+        return nullptr;
+    }
+
+    void setDebugModeOSRInfo(BaselineDebugModeOSRInfo* info) {
+        flags_ |= HAS_DEBUG_MODE_OSR_INFO;
+        debugModeOSRInfo_ = info;
+    }
+
+    void deleteDebugModeOSRInfo();
+
+    // See the HAS_OVERRIDE_PC comment.
+    bool hasOverridePc() const {
+        return flags_ & HAS_OVERRIDE_PC;
+    }
+
+    jsbytecode* overridePc() const {
+        MOZ_ASSERT(hasOverridePc());
+        return script()->offsetToPC(overrideOffset_);
+    }
+
+    jsbytecode* maybeOverridePc() const {
+        if (hasOverridePc())
+            return overridePc();
+        return nullptr;
+    }
+
+    void setOverridePc(jsbytecode* pc) {
+        flags_ |= HAS_OVERRIDE_PC;
+        overrideOffset_ = script()->pcToOffset(pc);
+    }
+
+    void clearOverridePc() {
+        flags_ &= ~HAS_OVERRIDE_PC;
+    }
+
+    void trace(JSTracer* trc, JitFrameIterator& frame);
+
+    bool isGlobalFrame() const {
+        return script()->isGlobalCode();
+    }
+    bool isModuleFrame() const {
+        return script()->module();
+    }
+    bool isEvalFrame() const {
+        return script()->isForEval();
+    }
+    bool isStrictEvalFrame() const {
+        return isEvalFrame() && script()->strict();
+    }
+    bool isNonStrictEvalFrame() const {
+        return isEvalFrame() && !script()->strict();
+    }
+    bool isNonGlobalEvalFrame() const;
+    bool isNonStrictDirectEvalFrame() const {
+        return isNonStrictEvalFrame() && isNonGlobalEvalFrame();
+    }
+    bool isFunctionFrame() const {
+        return CalleeTokenIsFunction(calleeToken());
+    }
+    bool isDebuggerEvalFrame() const {
+        return false;
+    }
+
+    JitFrameLayout* framePrefix() const {
+        uint8_t* fp = (uint8_t*)this + Size() + FramePointerOffset;
+        return (JitFrameLayout*)fp;
+    }
+
+    // Methods below are used by the compiler.
+    static size_t offsetOfCalleeToken() {
+        return FramePointerOffset + js::jit::JitFrameLayout::offsetOfCalleeToken();
+    }
+    static size_t offsetOfThis() {
+        return FramePointerOffset + js::jit::JitFrameLayout::offsetOfThis();
+    }
+    static size_t offsetOfEvalNewTarget() {
+        return FramePointerOffset + js::jit::JitFrameLayout::offsetOfEvalNewTarget();
+    }
+    static size_t offsetOfArg(size_t index) {
+        return FramePointerOffset + js::jit::JitFrameLayout::offsetOfActualArg(index);
+    }
+    static size_t offsetOfNumActualArgs() {
+        return FramePointerOffset + js::jit::JitFrameLayout::offsetOfNumActualArgs();
+    }
+    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.
+    static int reverseOffsetOfFrameSize() {
+        return -int(Size()) + offsetof(BaselineFrame, frameSize_);
+    }
+    static int reverseOffsetOfScratchValue() {
+        return -int(Size()) + offsetof(BaselineFrame, loScratchValue_);
+    }
+    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 reverseOffsetOfLocal(size_t index) {
+        return -int(Size()) - (index + 1) * sizeof(Value);
+    }
+};
+
+// Ensure the frame is 8-byte aligned (required on ARM).
+JS_STATIC_ASSERT(((sizeof(BaselineFrame) + BaselineFrame::FramePointerOffset) % 8) == 0);
+
+} // namespace jit
+} // namespace js
+
+#endif /* jit_BaselineFrame_h */