+
+/// isIdenticalTo - Return true if the specified instruction is exactly
+/// identical to the current one. This means that all operands match and any
+/// extra information (e.g. load is volatile) agree.
+bool Instruction::isIdenticalTo(Instruction *I) const {
+ if (getOpcode() != I->getOpcode() ||
+ getNumOperands() != I->getNumOperands() ||
+ getType() != I->getType())
+ return false;
+
+ // We have two instructions of identical opcode and #operands. Check to see
+ // if all operands are the same.
+ for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
+ if (getOperand(i) != I->getOperand(i))
+ return false;
+
+ // Check special state that is a part of some instructions.
+ if (const LoadInst *LI = dyn_cast<LoadInst>(this))
+ return LI->isVolatile() == cast<LoadInst>(I)->isVolatile();
+ if (const StoreInst *SI = dyn_cast<StoreInst>(this))
+ return SI->isVolatile() == cast<StoreInst>(I)->isVolatile();
+ if (const CmpInst *CI = dyn_cast<CmpInst>(this))
+ return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
+ if (const CallInst *CI = dyn_cast<CallInst>(this))
+ return CI->isTailCall() == cast<CallInst>(I)->isTailCall();
+ return true;
+}
+
+// isSameOperationAs
+bool Instruction::isSameOperationAs(Instruction *I) const {
+ if (getOpcode() != I->getOpcode() || getType() != I->getType() ||
+ getNumOperands() != I->getNumOperands())
+ return false;
+
+ // We have two instructions of identical opcode and #operands. Check to see
+ // if all operands are the same type
+ for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
+ if (getOperand(i)->getType() != I->getOperand(i)->getType())
+ return false;
+
+ // Check special state that is a part of some instructions.
+ if (const LoadInst *LI = dyn_cast<LoadInst>(this))
+ return LI->isVolatile() == cast<LoadInst>(I)->isVolatile();
+ if (const StoreInst *SI = dyn_cast<StoreInst>(this))
+ return SI->isVolatile() == cast<StoreInst>(I)->isVolatile();
+ if (const CmpInst *CI = dyn_cast<CmpInst>(this))
+ return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
+ if (const CallInst *CI = dyn_cast<CallInst>(this))
+ return CI->isTailCall() == cast<CallInst>(I)->isTailCall();
+
+ return true;
+}
+
+/// mayWriteToMemory - Return true if this instruction may modify memory.
+///
+bool Instruction::mayWriteToMemory() const {
+ switch (getOpcode()) {
+ default: return false;
+ case Instruction::Free:
+ case Instruction::Invoke:
+ case Instruction::Store:
+ case Instruction::VAArg:
+ return true;
+ case Instruction::Call:
+ if (!isa<IntrinsicInst>(this))
+ return true; // FIXME: workaround gcc bootstrap breakage
+ return !cast<CallInst>(this)->onlyReadsMemory();
+ case Instruction::Load:
+ return cast<LoadInst>(this)->isVolatile();
+ }
+}
+
+/// isAssociative - Return true if the instruction is associative:
+///
+/// Associative operators satisfy: x op (y op z) === (x op y) op z)
+///
+/// In LLVM, the Add, Mul, And, Or, and Xor operators are associative, when not
+/// applied to floating point types.
+///
+bool Instruction::isAssociative(unsigned Opcode, const Type *Ty) {
+ if (Opcode == And || Opcode == Or || Opcode == Xor)
+ return true;
+
+ // Add/Mul reassociate unless they are FP or FP vectors.
+ if (Opcode == Add || Opcode == Mul)
+ return !Ty->isFPOrFPVector();
+ return 0;
+}
+
+/// isCommutative - Return true if the instruction is commutative:
+///
+/// Commutative operators satisfy: (x op y) === (y op x)
+///
+/// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
+/// applied to any type.
+///
+bool Instruction::isCommutative(unsigned op) {
+ switch (op) {
+ case Add:
+ case Mul:
+ case And:
+ case Or:
+ case Xor:
+ return true;
+ default:
+ return false;
+ }
+}
+
+/// isTrappingInstruction - Return true if the instruction may trap.
+///
+bool Instruction::isTrapping(unsigned op) {
+ switch(op) {
+ case UDiv:
+ case SDiv:
+ case FDiv:
+ case URem:
+ case SRem:
+ case FRem:
+ case Load:
+ case Store:
+ case Call:
+ case Invoke:
+ return true;
+ default:
+ return false;
+ }
+}