Bug 998155 - IonMonkey: Constify congruentTo and mightAlias. r=h4writer

js/src/jit/MIR.cpp

@@ -158,7 +158,7 @@ MDefinition::valueHash() const
 }
 
 bool
-MDefinition::congruentIfOperandsEqual(MDefinition *ins) const
+MDefinition::congruentIfOperandsEqual(const MDefinition *ins) const
 {
     if (op() != ins->op())
         return false;
@@ -491,7 +491,7 @@ MConstant::valueHash() const
     return (HashNumber)JSVAL_TO_IMPL(value_).asBits;
 }
 bool
-MConstant::congruentTo(MDefinition *ins) const
+MConstant::congruentTo(const MDefinition *ins) const
 {
     if (!ins->isConstant())
         return false;
@@ -674,7 +674,7 @@ MParameter::valueHash() const
 }
 
 bool
-MParameter::congruentTo(MDefinition *ins) const
+MParameter::congruentTo(const MDefinition *ins) const
 {
     if (!ins->isParameter())
         return false;
@@ -760,7 +760,7 @@ MCallDOMNative::computeMovable()
 }
 
 bool
-MCallDOMNative::congruentTo(MDefinition *ins) const
+MCallDOMNative::congruentTo(const MDefinition *ins) const
 {
     if (!isMovable())
         return false;
@@ -768,7 +768,7 @@ MCallDOMNative::congruentTo(MDefinition *ins) const
     if (!ins->isCall())
         return false;
 
-    MCall *call = ins->toCall();
+    const MCall *call = ins->toCall();
 
     if (!call->isCallDOMNative())
         return false;
@@ -981,7 +981,7 @@ MPhi::foldsTo(TempAllocator &alloc, bool useValueNumbers)
 }
 
 bool
-MPhi::congruentTo(MDefinition *ins) const
+MPhi::congruentTo(const MDefinition *ins) const
 {
     if (!ins->isPhi())
         return false;
@@ -2717,7 +2717,7 @@ MNewArray::shouldUseVM() const
 }
 
 bool
-MLoadFixedSlot::mightAlias(MDefinition *store)
+MLoadFixedSlot::mightAlias(const MDefinition *store) const
 {
     if (store->isStoreFixedSlot() && store->toStoreFixedSlot()->slot() != slot())
         return false;
@@ -2725,51 +2725,51 @@ MLoadFixedSlot::mightAlias(MDefinition *store)
 }
 
 bool
-MAsmJSLoadHeap::mightAlias(MDefinition *def)
+MAsmJSLoadHeap::mightAlias(const MDefinition *def) const
 {
     if (def->isAsmJSStoreHeap()) {
-        MAsmJSStoreHeap *store = def->toAsmJSStoreHeap();
+        const MAsmJSStoreHeap *store = def->toAsmJSStoreHeap();
         if (store->viewType() != viewType())
             return true;
         if (!ptr()->isConstant() || !store->ptr()->isConstant())
             return true;
-        MConstant *otherPtr = store->ptr()->toConstant();
+        const MConstant *otherPtr = store->ptr()->toConstant();
         return ptr()->toConstant()->value() == otherPtr->value();
     }
     return true;
 }
 
 bool
-MAsmJSLoadHeap::congruentTo(MDefinition *ins) const
+MAsmJSLoadHeap::congruentTo(const MDefinition *ins) const
 {
     if (!ins->isAsmJSLoadHeap())
         return false;
-    MAsmJSLoadHeap *load = ins->toAsmJSLoadHeap();
+    const MAsmJSLoadHeap *load = ins->toAsmJSLoadHeap();
     return load->viewType() == viewType() && congruentIfOperandsEqual(load);
 }
 
 bool
-MAsmJSLoadGlobalVar::mightAlias(MDefinition *def)
+MAsmJSLoadGlobalVar::mightAlias(const MDefinition *def) const
 {
     if (def->isAsmJSStoreGlobalVar()) {
-        MAsmJSStoreGlobalVar *store = def->toAsmJSStoreGlobalVar();
+        const MAsmJSStoreGlobalVar *store = def->toAsmJSStoreGlobalVar();
         return store->globalDataOffset() == globalDataOffset_;
     }
     return true;
 }
 
 bool
-MAsmJSLoadGlobalVar::congruentTo(MDefinition *ins) const
+MAsmJSLoadGlobalVar::congruentTo(const MDefinition *ins) const
 {
     if (ins->isAsmJSLoadGlobalVar()) {
-        MAsmJSLoadGlobalVar *load = ins->toAsmJSLoadGlobalVar();
+        const MAsmJSLoadGlobalVar *load = ins->toAsmJSLoadGlobalVar();
         return globalDataOffset_ == load->globalDataOffset_;
     }
     return false;
 }
 
 bool
-MLoadSlot::mightAlias(MDefinition *store)
+MLoadSlot::mightAlias(const MDefinition *store) const
 {
     if (store->isStoreSlot() && store->toStoreSlot()->slot() != slot())
         return false;
@@ -2880,7 +2880,7 @@ MStoreTypedArrayElementStatic::length() const
 }
 
 bool
-MGetPropertyPolymorphic::mightAlias(MDefinition *store)
+MGetPropertyPolymorphic::mightAlias(const MDefinition *store) const
 {
     // Allow hoisting this instruction if the store does not write to a
     // slot read by this instruction.
@@ -2889,7 +2889,7 @@ MGetPropertyPolymorphic::mightAlias(MDefinition *store)
         return true;
 
     for (size_t i = 0; i < numShapes(); i++) {
-        Shape *shape = this->shape(i);
+        const Shape *shape = this->shape(i);
         if (shape->slot() < shape->numFixedSlots()) {
             // Fixed slot.
             uint32_t slot = shape->slot();

js/src/jit/MIR.h

@@ -376,10 +376,10 @@ class MDefinition : public MNode
     }
 
     virtual HashNumber valueHash() const;
-    virtual bool congruentTo(MDefinition *ins) const {
+    virtual bool congruentTo(const MDefinition *ins) const {
         return false;
     }
-    bool congruentIfOperandsEqual(MDefinition *ins) const;
+    bool congruentIfOperandsEqual(const MDefinition *ins) const;
     virtual MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
     virtual void analyzeEdgeCasesForward();
     virtual void analyzeEdgeCasesBackward();
@@ -584,7 +584,7 @@ class MDefinition : public MNode
     bool isEffectful() const {
         return getAliasSet().isStore();
     }
-    virtual bool mightAlias(MDefinition *store) {
+    virtual bool mightAlias(const MDefinition *store) const {
         // Return whether this load may depend on the specified store, given
         // that the alias sets intersect. This may be refined to exclude
         // possible aliasing in cases where alias set flags are too imprecise.
@@ -745,7 +745,7 @@ class MBinaryInstruction : public MAryInstruction<2>
         replaceOperand(1, temp);
     }
 
-    bool binaryCongruentTo(MDefinition *ins) const
+    bool binaryCongruentTo(const MDefinition *ins) const
     {
         if (op() != ins->op())
             return false;
@@ -756,9 +756,9 @@ class MBinaryInstruction : public MAryInstruction<2>
         if (isEffectful() || ins->isEffectful())
             return false;
 
-        MDefinition *left = getOperand(0);
-        MDefinition *right = getOperand(1);
-        MDefinition *tmp;
+        const MDefinition *left = getOperand(0);
+        const MDefinition *right = getOperand(1);
+        const MDefinition *tmp;
 
         if (isCommutative() && left->valueNumber() > right->valueNumber()) {
             tmp = right;
@@ -766,9 +766,9 @@ class MBinaryInstruction : public MAryInstruction<2>
             left = tmp;
         }
 
-        MBinaryInstruction *bi = static_cast<MBinaryInstruction *>(ins);
-        MDefinition *insLeft = bi->getOperand(0);
-        MDefinition *insRight = bi->getOperand(1);
+        const MBinaryInstruction *bi = static_cast<const MBinaryInstruction *>(ins);
+        const MDefinition *insLeft = bi->getOperand(0);
+        const MDefinition *insRight = bi->getOperand(1);
         if (isCommutative() && insLeft->valueNumber() > insRight->valueNumber()) {
             tmp = insRight;
             insRight = insLeft;
@@ -923,7 +923,7 @@ class MConstant : public MNullaryInstruction
     void printOpcode(FILE *fp) const;
 
     HashNumber valueHash() const;
-    bool congruentTo(MDefinition *ins) const;
+    bool congruentTo(const MDefinition *ins) const;
 
     AliasSet getAliasSet() const {
         return AliasSet::None();
@@ -991,7 +991,7 @@ class MParameter : public MNullaryInstruction
     void printOpcode(FILE *fp) const;
 
     HashNumber valueHash() const;
-    bool congruentTo(MDefinition *ins) const;
+    bool congruentTo(const MDefinition *ins) const;
 };
 
 class MCallee : public MNullaryInstruction
@@ -1006,7 +1006,7 @@ class MCallee : public MNullaryInstruction
   public:
     INSTRUCTION_HEADER(Callee)
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -1920,7 +1920,7 @@ class MCallDOMNative : public MCall
   public:
     virtual AliasSet getAliasSet() const MOZ_OVERRIDE;
 
-    virtual bool congruentTo(MDefinition *ins) const MOZ_OVERRIDE;
+    virtual bool congruentTo(const MDefinition *ins) const MOZ_OVERRIDE;
 
     virtual bool isCallDOMNative() const MOZ_OVERRIDE {
         return true;
@@ -2299,7 +2299,7 @@ class MCompare
 # endif
 
   protected:
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!binaryCongruentTo(ins))
             return false;
         return compareType() == ins->toCompare()->compareType() &&
@@ -2335,7 +2335,7 @@ class MBox : public MUnaryInstruction
         return new(alloc) MBox(alloc, ins);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -2417,7 +2417,7 @@ class MUnbox : public MUnaryInstruction, public BoxInputsPolicy
     bool fallible() const {
         return mode() != Infallible;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isUnbox() || ins->toUnbox()->mode() != mode())
             return false;
         return congruentIfOperandsEqual(ins);
@@ -2845,7 +2845,7 @@ class MToDouble
     }
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isToDouble() || ins->toToDouble()->conversion() != conversion())
             return false;
         return congruentIfOperandsEqual(ins);
@@ -2907,7 +2907,7 @@ class MToFloat32
     }
 
     virtual MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isToFloat32() || ins->toToFloat32()->conversion() != conversion())
             return false;
         return congruentIfOperandsEqual(ins);
@@ -2940,7 +2940,7 @@ class MAsmJSUnsignedToDouble
     }
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -2966,7 +2966,7 @@ class MAsmJSUnsignedToFloat32
     }
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -3024,7 +3024,7 @@ class MToInt32
         return conversion_;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -3060,7 +3060,7 @@ class MTruncateToInt32 : public MUnaryInstruction
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -3101,7 +3101,7 @@ class MToString : public MUnaryInstruction
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -3134,7 +3134,7 @@ class MBitNot
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
     void infer();
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -3237,7 +3237,7 @@ class MBinaryBitwiseInstruction
     virtual MDefinition *foldIfEqual()  = 0;
     virtual void infer(BaselineInspector *inspector, jsbytecode *pc);
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return binaryCongruentTo(ins);
     }
     AliasSet getAliasSet() const {
@@ -3453,7 +3453,7 @@ class MBinaryArithInstruction
 
     virtual void trySpecializeFloat32(TempAllocator &alloc);
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return binaryCongruentTo(ins);
     }
     AliasSet getAliasSet() const {
@@ -3504,7 +3504,7 @@ class MMinMax
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isMinMax())
             return false;
         if (isMax() != ins->toMinMax()->isMax())
@@ -3551,7 +3551,7 @@ class MAbs
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     bool fallible() const;
@@ -3592,7 +3592,7 @@ class MSqrt
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -3635,7 +3635,7 @@ class MAtan2
         return this;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -3678,7 +3678,7 @@ class MHypot
         return this;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -3719,7 +3719,7 @@ class MPow
     MDefinition *power() const {
         return rhs();
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     TypePolicy *typePolicy() {
@@ -3757,7 +3757,7 @@ class MPowHalf
     static MPowHalf *New(TempAllocator &alloc, MDefinition *input) {
         return new(alloc) MPowHalf(input);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     bool operandIsNeverNegativeInfinity() const {
@@ -3865,7 +3865,7 @@ class MMathFunction
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isMathFunction())
             return false;
         if (ins->toMathFunction()->function() != function())
@@ -4021,11 +4021,11 @@ class MMul : public MBinaryArithInstruction
         return 1;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isMul())
             return false;
 
-        MMul *mul = ins->toMul();
+        const MMul *mul = ins->toMul();
         if (canBeNegativeZero_ != mul->canBeNegativeZero())
             return false;
 
@@ -4060,7 +4060,7 @@ class MMul : public MBinaryArithInstruction
     bool truncate();
     bool isOperandTruncated(size_t index) const;
 
-    Mode mode() { return mode_; }
+    Mode mode() const { return mode_; }
 };
 
 class MDiv : public MBinaryArithInstruction
@@ -4257,7 +4257,7 @@ class MConcat
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -4296,7 +4296,7 @@ class MConcatPar
         return getOperand(2);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -4326,7 +4326,7 @@ class MCharCodeAt
         return this;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -4464,7 +4464,7 @@ class MLoadArrowThis
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -4570,7 +4570,7 @@ class MPhi MOZ_FINAL : public MDefinition, public InlineForwardListNode<MPhi>
 
     MDefinition *foldsTo(TempAllocator &alloc, bool useValueNumbers);
 
-    bool congruentTo(MDefinition *ins) const;
+    bool congruentTo(const MDefinition *ins) const;
 
     bool isIterator() const {
         return isIterator_;
@@ -5055,7 +5055,7 @@ class MStringReplace
         return new(alloc) MStringReplace(string, pattern, replacement);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5254,7 +5254,7 @@ class MSlots
     MDefinition *object() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5287,7 +5287,7 @@ class MElements
     MDefinition *object() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5324,7 +5324,7 @@ class MConstantElements : public MNullaryInstruction
         return (HashNumber)(size_t) value_;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return ins->isConstantElements() && ins->toConstantElements()->value() == value();
     }
 
@@ -5355,7 +5355,7 @@ class MConvertElementsToDoubles
     MDefinition *elements() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5403,7 +5403,7 @@ class MMaybeToDoubleElement
     MDefinition *value() const {
         return getOperand(1);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5432,7 +5432,7 @@ class MInitializedLength
     MDefinition *elements() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5491,7 +5491,7 @@ class MArrayLength
     MDefinition *elements() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5554,7 +5554,7 @@ class MTypedArrayLength
     MDefinition *object() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5591,7 +5591,7 @@ class MTypedArrayElements
     MDefinition *object() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5625,7 +5625,7 @@ class MNeuterCheck
         return getOperand(0);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
 
@@ -5662,7 +5662,7 @@ class MTypedObjectElements
     MDefinition *object() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -5817,10 +5817,10 @@ class MBoundsCheck
     void setMaximum(int32_t n) {
         maximum_ = n;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isBoundsCheck())
             return false;
-        MBoundsCheck *other = ins->toBoundsCheck();
+        const MBoundsCheck *other = ins->toBoundsCheck();
         if (minimum() != other->minimum() || maximum() != other->maximum())
             return false;
         return congruentIfOperandsEqual(other);
@@ -5923,10 +5923,10 @@ class MLoadElement
     bool fallible() const {
         return needsHoleCheck();
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadElement())
             return false;
-        MLoadElement *other = ins->toLoadElement();
+        const MLoadElement *other = ins->toLoadElement();
         if (needsHoleCheck() != other->needsHoleCheck())
             return false;
         if (loadDoubles() != other->loadDoubles())
@@ -5986,10 +5986,10 @@ class MLoadElementHole
     bool needsHoleCheck() const {
         return needsHoleCheck_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadElementHole())
             return false;
-        MLoadElementHole *other = ins->toLoadElementHole();
+        const MLoadElementHole *other = ins->toLoadElementHole();
         if (needsHoleCheck() != other->needsHoleCheck())
             return false;
         if (needsNegativeIntCheck() != other->needsNegativeIntCheck())
@@ -6305,10 +6305,10 @@ class MLoadTypedArrayElement
         return AliasSet::Load(AliasSet::TypedArrayElement);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadTypedArrayElement())
             return false;
-        MLoadTypedArrayElement *other = ins->toLoadTypedArrayElement();
+        const MLoadTypedArrayElement *other = ins->toLoadTypedArrayElement();
         if (arrayType_ != other->arrayType_)
             return false;
         return congruentIfOperandsEqual(other);
@@ -6366,10 +6366,10 @@ class MLoadTypedArrayElementHole
     MDefinition *index() const {
         return getOperand(1);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadTypedArrayElementHole())
             return false;
-        MLoadTypedArrayElementHole *other = ins->toLoadTypedArrayElementHole();
+        const MLoadTypedArrayElementHole *other = ins->toLoadTypedArrayElementHole();
         if (arrayType() != other->arrayType())
             return false;
         if (allowDouble() != other->allowDouble())
@@ -6684,7 +6684,7 @@ class MClampToUint8
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -6724,7 +6724,7 @@ class MLoadFixedSlot
     size_t slot() const {
         return slot_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadFixedSlot())
             return false;
         if (slot() != ins->toLoadFixedSlot()->slot())
@@ -6736,7 +6736,7 @@ class MLoadFixedSlot
         return AliasSet::Load(AliasSet::FixedSlot);
     }
 
-    bool mightAlias(MDefinition *store);
+    bool mightAlias(const MDefinition *store) const;
 };
 
 class MStoreFixedSlot
@@ -6938,7 +6938,7 @@ class MGetPropertyCache
     }
     TypePolicy *typePolicy() { return this; }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!idempotent_)
             return false;
         if (!ins->isGetPropertyCache())
@@ -6998,7 +6998,7 @@ class MGetPropertyPolymorphic
         return new(alloc) MGetPropertyPolymorphic(alloc, obj, name);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isGetPropertyPolymorphic())
             return false;
         if (name() != ins->toGetPropertyPolymorphic()->name())
@@ -7031,7 +7031,7 @@ class MGetPropertyPolymorphic
         return AliasSet::Load(AliasSet::ObjectFields | AliasSet::FixedSlot | AliasSet::DynamicSlot);
     }
 
-    bool mightAlias(MDefinition *store);
+    bool mightAlias(const MDefinition *store) const;
 };
 
 // Emit code to store a value to an object's slots if its shape matches
@@ -7362,7 +7362,7 @@ class MGuardShape
     BailoutKind bailoutKind() const {
         return bailoutKind_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isGuardShape())
             return false;
         if (shape() != ins->toGuardShape()->shape())
@@ -7414,7 +7414,7 @@ class MGuardObjectType
     bool bailOnEquality() const {
         return bailOnEquality_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isGuardObjectType())
             return false;
         if (typeObject() != ins->toGuardObjectType()->typeObject())
@@ -7466,7 +7466,7 @@ class MGuardObjectIdentity
     bool bailOnEquality() const {
         return bailOnEquality_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isGuardObjectIdentity())
             return false;
         if (singleObject() != ins->toGuardObjectIdentity()->singleObject())
@@ -7511,7 +7511,7 @@ class MGuardClass
     const Class *getClass() const {
         return class_;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isGuardClass())
             return false;
         if (getClass() != ins->toGuardClass()->getClass())
@@ -7556,7 +7556,7 @@ class MLoadSlot
         return slot_;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isLoadSlot())
             return false;
         if (slot() != ins->toLoadSlot()->slot())
@@ -7567,7 +7567,7 @@ class MLoadSlot
         JS_ASSERT(slots()->type() == MIRType_Slots);
         return AliasSet::Load(AliasSet::DynamicSlot);
     }
-    bool mightAlias(MDefinition *store);
+    bool mightAlias(const MDefinition *store) const;
 };
 
 // Inline call to access a function's environment (scope chain).
@@ -8297,7 +8297,7 @@ class MGetDOMProperty
         return this;
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!isDomMovable())
             return false;
 
@@ -8374,7 +8374,7 @@ class MStringLength
     MDefinition *string() const {
         return getOperand(0);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -8651,10 +8651,10 @@ class MInArray
     AliasSet getAliasSet() const {
         return AliasSet::Load(AliasSet::Element);
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         if (!ins->isInArray())
             return false;
-        MInArray *other = ins->toInArray();
+        const MInArray *other = ins->toInArray();
         if (needsHoleCheck() != other->needsHoleCheck())
             return false;
         if (needsNegativeIntCheck() != other->needsNegativeIntCheck())
@@ -8735,7 +8735,7 @@ class MArgumentsLength : public MNullaryInstruction
         return new(alloc) MArgumentsLength();
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -8775,7 +8775,7 @@ class MGetFrameArgument
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -8816,7 +8816,7 @@ class MSetFrameArgument
         return getOperand(0);
     }
 
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return false;
     }
     AliasSet getAliasSet() const {
@@ -8954,7 +8954,7 @@ class MGuardThreadExclusive
     BailoutKind bailoutKind() const {
         return Bailout_Normal;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -8985,7 +8985,7 @@ class MFilterTypeSet
         return new(alloc) MFilterTypeSet(def, types);
     }
 
-    bool congruentTo(MDefinition *def) const {
+    bool congruentTo(const MDefinition *def) const {
         return false;
     }
     AliasSet getAliasSet() const {
@@ -9028,7 +9028,7 @@ class MTypeBarrier
         return this;
     }
 
-    bool congruentTo(MDefinition *def) const {
+    bool congruentTo(const MDefinition *def) const {
         return false;
     }
     AliasSet getAliasSet() const {
@@ -9559,7 +9559,7 @@ class MHaveSameClass
     TypePolicy *typePolicy() {
         return this;
     }
-    bool congruentTo(MDefinition *ins) const {
+    bool congruentTo(const MDefinition *ins) const {
         return congruentIfOperandsEqual(ins);
     }
     AliasSet getAliasSet() const {
@@ -9689,11 +9689,11 @@ class MAsmJSLoadHeap : public MUnaryInstruction, public MAsmJSHeapAccess
 
     MDefinition *ptr() const { return getOperand(0); }
 
-    bool congruentTo(MDefinition *ins) const;
+    bool congruentTo(const MDefinition *ins) const;
     AliasSet getAliasSet() const {
         return AliasSet::Load(AliasSet::AsmJSHeap);
     }
-    bool mightAlias(MDefinition *def);
+    bool mightAlias(const MDefinition *def) const;
 };
 
 class MAsmJSStoreHeap : public MBinaryInstruction, public MAsmJSHeapAccess
@@ -9743,13 +9743,13 @@ class MAsmJSLoadGlobalVar : public MNullaryInstruction
 
     unsigned globalDataOffset() const { return globalDataOffset_; }
 
-    bool congruentTo(MDefinition *ins) const;
+    bool congruentTo(const MDefinition *ins) const;
 
     AliasSet getAliasSet() const {
         return isConstant_ ? AliasSet::None() : AliasSet::Load(AliasSet::AsmJSGlobalVar);
     }
 
-    bool mightAlias(MDefinition *def);
+    bool mightAlias(const MDefinition *def) const;
 };
 
 class MAsmJSStoreGlobalVar : public MUnaryInstruction