diff --git a/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp b/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp --- a/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp +++ b/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp @@ -26,6 +26,7 @@ #include "llvm/IR/IRBuilder.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/PatternMatch.h" +#include "llvm/Support/KnownBits.h" #include "llvm/Pass.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" @@ -344,6 +345,13 @@ if (match(V, m_NUWAdd(m_Value(Op0), m_Value(Op1)))) { return MergeResults(Op0, Op1, IsSigned); } + + // Decompose or if it can be represented as an addition. + if (match(V, m_Or(m_Value(Op0), m_ConstantInt(CI)))) { + auto KnownBits = computeKnownBits(Op0, DL, MaxAnalysisRecursionDepth - 1); + if (CI->getZExtValue() < pow(2, KnownBits.Zero.getZExtValue())) + return MergeResults(Op0, CI, IsSigned); + } if (match(V, m_NSWAdd(m_Value(Op0), m_Value(Op1)))) { if (!isKnownNonNegative(Op0, DL, /*Depth=*/MaxAnalysisRecursionDepth - 1)) Preconditions.emplace_back(CmpInst::ICMP_SGE, Op0, diff --git a/llvm/test/Transforms/ConstraintElimination/or.ll b/llvm/test/Transforms/ConstraintElimination/or.ll --- a/llvm/test/Transforms/ConstraintElimination/or.ll +++ b/llvm/test/Transforms/ConstraintElimination/or.ll @@ -446,13 +446,13 @@ ; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_1:%.*]] = or i8 [[START]], 1 ; CHECK-NEXT: [[T_1:%.*]] = icmp ult i8 [[START_1]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_1]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_2:%.*]] = or i8 [[START]], 2 ; CHECK-NEXT: [[T_2:%.*]] = icmp ult i8 [[START_2]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_2]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_3:%.*]] = or i8 [[START]], 3 ; CHECK-NEXT: [[T_3:%.*]] = icmp ult i8 [[START_3]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_3]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_4:%.*]] = or i8 [[START]], 4 ; CHECK-NEXT: [[C_4:%.*]] = icmp ult i8 [[START_4]], [[HIGH]] ; CHECK-NEXT: call void @use(i1 [[C_4]]) @@ -499,16 +499,16 @@ ; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_1:%.*]] = or i8 [[START]], 1 ; CHECK-NEXT: [[T_1:%.*]] = icmp ule i8 [[START_1]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_1]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_2:%.*]] = or i8 [[START]], 2 ; CHECK-NEXT: [[T_2:%.*]] = icmp ule i8 [[START_2]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_2]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_3:%.*]] = or i8 [[START]], 3 ; CHECK-NEXT: [[T_3:%.*]] = icmp ule i8 [[START_3]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_3]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_4:%.*]] = or i8 [[START]], 4 ; CHECK-NEXT: [[T_4:%.*]] = icmp ule i8 [[START_4]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[T_4]]) +; CHECK-NEXT: call void @use(i1 true) ; CHECK-NEXT: [[START_5:%.*]] = or i8 [[START]], 5 ; CHECK-NEXT: [[C_5:%.*]] = icmp ule i8 [[START_5]], [[HIGH]] ; CHECK-NEXT: call void @use(i1 [[C_5]]) @@ -559,16 +559,16 @@ ; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_1:%.*]] = or i8 [[START]], 1 ; CHECK-NEXT: [[F_1:%.*]] = icmp ugt i8 [[START_1]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_1]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_2:%.*]] = or i8 [[START]], 2 ; CHECK-NEXT: [[F_2:%.*]] = icmp ugt i8 [[START_2]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_2]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_3:%.*]] = or i8 [[START]], 3 ; CHECK-NEXT: [[F_3:%.*]] = icmp ugt i8 [[START_3]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_3]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_4:%.*]] = or i8 [[START]], 4 ; CHECK-NEXT: [[F_4:%.*]] = icmp ugt i8 [[START_4]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_4]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_5:%.*]] = or i8 [[START]], 5 ; CHECK-NEXT: [[C_5:%.*]] = icmp ugt i8 [[START_5]], [[HIGH]] ; CHECK-NEXT: call void @use(i1 [[C_5]]) @@ -624,13 +624,13 @@ ; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_1:%.*]] = or i8 [[START]], 1 ; CHECK-NEXT: [[F_1:%.*]] = icmp uge i8 [[START_1]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_1]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_2:%.*]] = or i8 [[START]], 2 ; CHECK-NEXT: [[F_2:%.*]] = icmp uge i8 [[START_2]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_2]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_3:%.*]] = or i8 [[START]], 3 ; CHECK-NEXT: [[F_3:%.*]] = icmp uge i8 [[START_3]], [[HIGH]] -; CHECK-NEXT: call void @use(i1 [[F_3]]) +; CHECK-NEXT: call void @use(i1 false) ; CHECK-NEXT: [[START_4:%.*]] = or i8 [[START]], 4 ; CHECK-NEXT: [[C_4:%.*]] = icmp uge i8 [[START_4]], [[HIGH]] ; CHECK-NEXT: call void @use(i1 [[C_4]])