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| author | Matt Arsenault <Matthew.Arsenault@amd.com> | 2019-06-24 21:37:02 +0000 |
|---|---|---|
| committer | Matt Arsenault <Matthew.Arsenault@amd.com> | 2019-06-24 21:37:02 +0000 |
| commit | 5d82ecd5d952bbd92dc356bd9220be818f64993e (patch) | |
| tree | a9c11d7281e653c9a46671ed2d571a2c92cc0257 /llvm | |
| parent | 5a89ba7343a6f108397eab94fa843098b22cde74 (diff) | |
| download | bcm5719-llvm-5d82ecd5d952bbd92dc356bd9220be818f64993e.tar.gz bcm5719-llvm-5d82ecd5d952bbd92dc356bd9220be818f64993e.zip | |
InstCombine: Preserve nuw when reassociating nuw ops [2/3]
Alive says this is OK.
llvm-svn: 364234
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstructionCombining.cpp | 12 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/reassociate-nuw.ll | 6 |
2 files changed, 13 insertions, 5 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp index 3243d8fda3d..fcbe738aad7 100644 --- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -431,8 +431,14 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { Op0->getOpcode() == Opcode && Op1->getOpcode() == Opcode && match(Op0, m_OneUse(m_BinOp(m_Value(A), m_Constant(C1)))) && match(Op1, m_OneUse(m_BinOp(m_Value(B), m_Constant(C2))))) { - BinaryOperator *NewBO = BinaryOperator::Create(Opcode, A, B); - if (isa<FPMathOperator>(NewBO)) { + bool IsNUW = hasNoUnsignedWrap(I) && + hasNoUnsignedWrap(*Op0) && + hasNoUnsignedWrap(*Op1); + BinaryOperator *NewBO = (IsNUW && Opcode == Instruction::Add) ? + BinaryOperator::CreateNUW(Opcode, A, B) : + BinaryOperator::Create(Opcode, A, B); + + if (isa<FPMathOperator>(NewBO)) { FastMathFlags Flags = I.getFastMathFlags(); Flags &= Op0->getFastMathFlags(); Flags &= Op1->getFastMathFlags(); @@ -445,6 +451,8 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { // Conservatively clear the optional flags, since they may not be // preserved by the reassociation. ClearSubclassDataAfterReassociation(I); + if (IsNUW) + I.setHasNoUnsignedWrap(true); Changed = true; continue; diff --git a/llvm/test/Transforms/InstCombine/reassociate-nuw.ll b/llvm/test/Transforms/InstCombine/reassociate-nuw.ll index 66c06b464d6..22ad8c259d4 100644 --- a/llvm/test/Transforms/InstCombine/reassociate-nuw.ll +++ b/llvm/test/Transforms/InstCombine/reassociate-nuw.ll @@ -55,8 +55,8 @@ define i32 @no_reassoc_add_none_nuw(i32 %x) { define i32 @reassoc_x2_add_nuw(i32 %x, i32 %y) { ; CHECK-LABEL: @reassoc_x2_add_nuw( -; CHECK-NEXT: [[ADD1:%.*]] = add i32 [[X:%.*]], [[Y:%.*]] -; CHECK-NEXT: [[ADD2:%.*]] = add i32 [[ADD1]], 12 +; CHECK-NEXT: [[ADD1:%.*]] = add nuw i32 [[X:%.*]], [[Y:%.*]] +; CHECK-NEXT: [[ADD2:%.*]] = add nuw i32 [[ADD1]], 12 ; CHECK-NEXT: ret i32 [[ADD2]] ; %add0 = add nuw i32 %x, 4 @@ -68,7 +68,7 @@ define i32 @reassoc_x2_add_nuw(i32 %x, i32 %y) { define i32 @reassoc_x2_mul_nuw(i32 %x, i32 %y) { ; CHECK-LABEL: @reassoc_x2_mul_nuw( ; CHECK-NEXT: [[MUL1:%.*]] = mul i32 [[X:%.*]], [[Y:%.*]] -; CHECK-NEXT: [[MUL2:%.*]] = mul i32 [[MUL1]], 45 +; CHECK-NEXT: [[MUL2:%.*]] = mul nuw i32 [[MUL1]], 45 ; CHECK-NEXT: ret i32 [[MUL2]] ; %mul0 = mul nuw i32 %x, 5 |
