Index: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp =================================================================== --- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -5150,7 +5150,7 @@ return V; if (N0.getOpcode() == ISD::ADD && N1.getOpcode() == ISD::SRL && - VT.getSizeInBits() <= 64) { + VT.getSizeInBits() <= 64 && N0->hasOneUse()) { if (ConstantSDNode *ADDI = dyn_cast(N0.getOperand(1))) { if (ConstantSDNode *SRLI = dyn_cast(N1.getOperand(1))) { // Look for (and (add x, c1), (lshr y, c2)). If C1 wasn't a legal Index: llvm/test/CodeGen/AArch64/arm64-srl-and.ll =================================================================== --- /dev/null +++ llvm/test/CodeGen/AArch64/arm64-srl-and.ll @@ -0,0 +1,29 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc -mtriple=aarch64-linux-gnu -O3 < %s | FileCheck %s + +; Disable the dagcombine if operand has multi use + +@g = dso_local local_unnamed_addr global i16 0, align 4 +define dso_local noundef i32 @srl_and() local_unnamed_addr { +; CHECK-LABEL: srl_and: +; CHECK: // %bb.0: // %entry +; CHECK-NEXT: adrp x8, g +; CHECK-NEXT: ldrh w8, [x8, :lo12:g] +; CHECK-NEXT: mov w9, #50 +; CHECK-NEXT: eor w8, w8, w9 +; CHECK-NEXT: mov w9, #65535 +; CHECK-NEXT: add w8, w8, w9 +; CHECK-NEXT: and w0, w8, w8, lsr #16 +; CHECK-NEXT: ret +entry: + %0 = load i16, i16* @g, align 4 + %1 = xor i16 %0, 50 + %tobool = icmp ne i16 %1, 0 + %lor.ext = zext i1 %tobool to i32 + %sub = add i16 %1, -1 + + %srl = zext i16 %sub to i32 + %and = and i32 %srl, %lor.ext + + ret i32 %and +}