[InstCombine][IR] Add a commutable BinOp matcher. Use it to reduce some code. NFC

llvm-svn: 300030

2 files changed, 9 insertions, 2 deletions

diff --git a/llvm/include/llvm/IR/PatternMatch.h b/llvm/include/llvm/IR/PatternMatch.h
index 34f3724805b..0788690fb41 100644
--- a/llvm/include/llvm/IR/PatternMatch.h
+++ b/llvm/include/llvm/IR/PatternMatch.h
@@ -1348,6 +1348,14 @@ template <typename Val_t> inline Signum_match<Val_t> m_Signum(const Val_t &V) {
 // Matchers for two-operands operators with the operators in either order
 //
 
+/// \brief Matches a Add with LHS and RHS in either order.
+template<typename LHS, typename RHS>
+inline match_combine_or<AnyBinaryOp_match<LHS, RHS>,
+                        AnyBinaryOp_match<RHS, LHS>>
+m_c_BinOp(const LHS &L, const RHS &R) {
+  return m_CombineOr(m_BinOp(L, R), m_BinOp(R, L));
+}
+
 /// \brief Matches an ICmp with a predicate over LHS and RHS in either order.
 /// Does not swap the predicate.
 template<typename LHS, typename RHS>
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 9bbc5b281ab..ea8c0a6d38b 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -1272,8 +1272,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
       case Instruction::Sub:
         Value *X;
         ConstantInt *C1;
-        if (match(Op0I, m_BinOp(m_ZExt(m_Value(X)), m_ConstantInt(C1))) ||
-            match(Op0I, m_BinOp(m_ConstantInt(C1), m_ZExt(m_Value(X))))) {
+        if (match(Op0I, m_c_BinOp(m_ZExt(m_Value(X)), m_ConstantInt(C1)))) {
           if (AndRHSMask.isIntN(X->getType()->getScalarSizeInBits())) {
             auto *TruncC1 = ConstantExpr::getTrunc(C1, X->getType());
             Value *BinOp;