diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -3209,7 +3209,7 @@ // Try to find umax(a,b) - b or a - umin(a,b) patterns // they may be converted to usubsat(a,b). - if (Op0.getOpcode() == ISD::UMAX) { + if (Op0.getOpcode() == ISD::UMAX && Op0.hasOneUse()) { SDValue MaxLHS = Op0.getOperand(0); SDValue MaxRHS = Op0.getOperand(1); if (MaxLHS == Op1) @@ -3218,7 +3218,7 @@ return getTruncatedUSUBSAT(DstVT, SubVT, MaxLHS, Op1, DAG, SDLoc(N)); } - if (Op1.getOpcode() == ISD::UMIN) { + if (Op1.getOpcode() == ISD::UMIN && Op1.hasOneUse()) { SDValue MinLHS = Op1.getOperand(0); SDValue MinRHS = Op1.getOperand(1); if (MinLHS == Op0) @@ -3229,7 +3229,8 @@ // sub(a,trunc(umin(zext(a),b))) -> usubsat(a,trunc(umin(b,SatLimit))) if (Op1.getOpcode() == ISD::TRUNCATE && - Op1.getOperand(0).getOpcode() == ISD::UMIN) { + Op1.getOperand(0).getOpcode() == ISD::UMIN && + Op1.getOperand(0).hasOneUse()) { SDValue MinLHS = Op1.getOperand(0).getOperand(0); SDValue MinRHS = Op1.getOperand(0).getOperand(1); if (MinLHS.getOpcode() == ISD::ZERO_EXTEND && MinLHS.getOperand(0) == Op0) diff --git a/llvm/test/CodeGen/PowerPC/sat-add.ll b/llvm/test/CodeGen/PowerPC/sat-add.ll --- a/llvm/test/CodeGen/PowerPC/sat-add.ll +++ b/llvm/test/CodeGen/PowerPC/sat-add.ll @@ -864,3 +864,33 @@ ret <4 x i128> %c } +define i64 @unsigned_sat_constant_i64_with_single_use(i64 %x) { +; CHECK-LABEL: unsigned_sat_constant_i64_with_single_use: +; CHECK: # %bb.0: +; CHECK-NEXT: addi 4, 3, -4 +; CHECK-NEXT: cmpld 4, 3 +; CHECK-NEXT: iselgt 3, 0, 4 +; CHECK-NEXT: blr + %umin = call i64 @llvm.umin.i64(i64 %x, i64 4) + %sub = sub i64 %x, %umin + ret i64 %sub +} + +define i64 @unsigned_sat_constant_i64_with_multiple_use(i64 %x, i64 %y) { +; CHECK-LABEL: unsigned_sat_constant_i64_with_multiple_use: +; CHECK: # %bb.0: +; CHECK-NEXT: li 5, 4 +; CHECK-NEXT: cmpldi 3, 4 +; CHECK-NEXT: isellt 5, 3, 5 +; CHECK-NEXT: sub 3, 3, 5 +; CHECK-NEXT: add 4, 4, 5 +; CHECK-NEXT: mulld 3, 3, 4 +; CHECK-NEXT: blr + %umin = call i64 @llvm.umin.i64(i64 %x, i64 4) + %sub = sub i64 %x, %umin + %add = add i64 %y, %umin + %res = mul i64 %sub, %add + ret i64 %res +} + +declare i64 @llvm.umin.i64(i64, i64)