New isAssociative/isCommutative inspection methods, graciously contributed by
Casey Carter.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Instruction.h b/include/llvm/Instruction.h
index 89c6409..ca01e30 100644
--- a/include/llvm/Instruction.h
+++ b/include/llvm/Instruction.h
@@ -74,6 +74,27 @@
return iType >= BinaryOpsBegin && iType < BinaryOpsEnd;
}
+ /// 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 isAssociative() const { return isAssociative(getOpcode(), getType()); }
+ static bool isAssociative(unsigned op, const Type *Ty);
+
+ /// isCommutative - Return true if the instruction is commutative:
+ ///
+ /// Commutative operators satistify: (x op y) === (y op x)
+ ///
+ /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
+ /// applied to any type.
+ ///
+ bool isCommutative() const { return isCommutative(getOpcode()); }
+ static bool isCommutative(unsigned op);
+
+
virtual void print(std::ostream &OS) const;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
diff --git a/lib/VMCore/Instruction.cpp b/lib/VMCore/Instruction.cpp
index 2084e69..95267aa 100644
--- a/lib/VMCore/Instruction.cpp
+++ b/lib/VMCore/Instruction.cpp
@@ -97,3 +97,42 @@
return 0;
}
+
+
+/// 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 == Add || Opcode == Mul ||
+ Opcode == And || Opcode == Or || Opcode == Xor) {
+ // Floating point operations do not associate!
+ return !Ty->isFloatingPoint();
+ }
+ return 0;
+}
+
+/// isCommutative - Return true if the instruction is commutative:
+///
+/// Commutative operators satistify: (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:
+ case SetEQ:
+ case SetNE:
+ return true;
+ default:
+ return false;
+ }
+}