diff options
| -rw-r--r-- | llvm/lib/Transforms/Scalar/SCCP.cpp | 7 | ||||
| -rw-r--r-- | llvm/test/Transforms/SCCP/logical-nuke.ll | 9 |
2 files changed, 13 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp index 2c1364d77cf..279c710f9e1 100644 --- a/llvm/lib/Transforms/Scalar/SCCP.cpp +++ b/llvm/lib/Transforms/Scalar/SCCP.cpp @@ -916,7 +916,8 @@ void SCCPSolver::visitBinaryOperator(Instruction &I) { // If this is an AND or OR with 0 or -1, it doesn't matter that the other // operand is overdefined. - if (I.getOpcode() == Instruction::And || I.getOpcode() == Instruction::Or) { + if (I.getOpcode() == Instruction::And || I.getOpcode() == Instruction::Mul || + I.getOpcode() == Instruction::Or) { LatticeVal *NonOverdefVal = nullptr; if (!V1State.isOverdefined()) NonOverdefVal = &V1State; @@ -927,8 +928,10 @@ void SCCPSolver::visitBinaryOperator(Instruction &I) { if (NonOverdefVal->isUnknown()) return; - if (I.getOpcode() == Instruction::And) { + if (I.getOpcode() == Instruction::And || + I.getOpcode() == Instruction::Mul) { // X and 0 = 0 + // X * 0 = 0 if (NonOverdefVal->getConstant()->isNullValue()) return markConstant(IV, &I, NonOverdefVal->getConstant()); } else { diff --git a/llvm/test/Transforms/SCCP/logical-nuke.ll b/llvm/test/Transforms/SCCP/logical-nuke.ll index 4ef52a25539..76884dbab4b 100644 --- a/llvm/test/Transforms/SCCP/logical-nuke.ll +++ b/llvm/test/Transforms/SCCP/logical-nuke.ll @@ -1,6 +1,6 @@ ; RUN: opt < %s -sccp -S | FileCheck %s -; Test that SCCP has basic knowledge of when and/or nuke overdefined values. +; Test that SCCP has basic knowledge of when and/or/mul nuke overdefined values. ; CHECK-LABEL: test ; CHECK: ret i32 0 @@ -29,3 +29,10 @@ define i32 @test4(i32 %X) { %Y = or i32 %X, undef ret i32 %Y } + +; CHECK-LABEL: test5 +; CHECK: ret i32 0 +define i32 @test5(i32 %foo) { + %patatino = mul i32 %foo, undef + ret i32 %patatino +} |
