Index: llvm/lib/IR/ConstantRange.cpp =================================================================== --- llvm/lib/IR/ConstantRange.cpp +++ llvm/lib/IR/ConstantRange.cpp @@ -1478,6 +1478,13 @@ APInt OtherMax = Other.getUnsignedMax(); + bool Neg = false; + if (getSingleElement() && isAllNegative()) { + Neg = true; + Min = Min.abs(); + Max = Max.abs(); + } + // There's overflow! if (OtherMax.ugt(Max.countl_zero())) return getFull(); @@ -1487,7 +1494,12 @@ Min <<= Other.getUnsignedMin(); Max <<= OtherMax; - return ConstantRange::getNonEmpty(std::move(Min), std::move(Max) + 1); + if (Neg) { + Min = -Min; + Max = -Max; + return ConstantRange::getNonEmpty(std::move(Max), std::move(Min) + 1); + } else + return ConstantRange::getNonEmpty(std::move(Min), std::move(Max) + 1); } ConstantRange Index: llvm/test/Transforms/FunctionSpecialization/and-add-shl.ll =================================================================== --- llvm/test/Transforms/FunctionSpecialization/and-add-shl.ll +++ llvm/test/Transforms/FunctionSpecialization/and-add-shl.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2 -; RUN: opt < %s -passes=instcombine -S | FileCheck %s +; RUN: opt < %s -passes=ipsccp -S | FileCheck %s declare void @llvm.assume(i1) declare i8 @llvm.ctpop.i8(i8) @@ -8,12 +8,11 @@ define i8 @and_add_shl(i8 %x) { ; CHECK-LABEL: define i8 @and_add_shl ; CHECK-SAME: (i8 [[X:%.*]]) { -; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ult i8 [[X]], 6 +; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ule i8 [[X]], 5 ; CHECK-NEXT: call void @llvm.assume(i1 [[OP1_P2]]) -; CHECK-NEXT: [[NOTMASK:%.*]] = shl nsw i8 -1, [[X]] -; CHECK-NEXT: [[SUB:%.*]] = and i8 [[NOTMASK]], 32 -; CHECK-NEXT: [[R:%.*]] = xor i8 [[SUB]], 32 -; CHECK-NEXT: ret i8 [[R]] +; CHECK-NEXT: [[SHIFT:%.*]] = shl nuw nsw i8 1, [[X]] +; CHECK-NEXT: [[SUB:%.*]] = add nsw i8 [[SHIFT]], -1 +; CHECK-NEXT: ret i8 0 ; %op1_p2 = icmp ule i8 %x, 5 call void @llvm.assume(i1 %op1_p2) @@ -27,12 +26,11 @@ define i8 @and_not_shl(i8 %x) { ; CHECK-LABEL: define i8 @and_not_shl ; CHECK-SAME: (i8 [[X:%.*]]) { -; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ult i8 [[X]], 6 +; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ule i8 [[X]], 5 ; CHECK-NEXT: call void @llvm.assume(i1 [[OP1_P2]]) -; CHECK-NEXT: [[SHIFT:%.*]] = shl i8 -1, [[X]] -; CHECK-NEXT: [[NOT:%.*]] = and i8 [[SHIFT]], 32 -; CHECK-NEXT: [[R:%.*]] = xor i8 [[NOT]], 32 -; CHECK-NEXT: ret i8 [[R]] +; CHECK-NEXT: [[SHIFT:%.*]] = shl nsw i8 -1, [[X]] +; CHECK-NEXT: [[NOT:%.*]] = xor i8 [[SHIFT]], -1 +; CHECK-NEXT: ret i8 0 ; %op1_p2 = icmp ule i8 %x, 5 call void @llvm.assume(i1 %op1_p2) @@ -46,11 +44,11 @@ define i8 @and_add_shl_overlap(i8 %x) { ; CHECK-LABEL: define i8 @and_add_shl_overlap ; CHECK-SAME: (i8 [[X:%.*]]) { -; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ult i8 [[X]], 7 +; CHECK-NEXT: [[OP1_P2:%.*]] = icmp ule i8 [[X]], 6 ; CHECK-NEXT: call void @llvm.assume(i1 [[OP1_P2]]) -; CHECK-NEXT: [[NOTMASK:%.*]] = shl nsw i8 -1, [[X]] -; CHECK-NEXT: [[SUB:%.*]] = and i8 [[NOTMASK]], 32 -; CHECK-NEXT: [[R:%.*]] = xor i8 [[SUB]], 32 +; CHECK-NEXT: [[SHIFT:%.*]] = shl nuw nsw i8 1, [[X]] +; CHECK-NEXT: [[SUB:%.*]] = add nsw i8 [[SHIFT]], -1 +; CHECK-NEXT: [[R:%.*]] = and i8 [[SUB]], 32 ; CHECK-NEXT: ret i8 [[R]] ; %op1_p2 = icmp ule i8 %x, 6