diff options
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 15 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/2008-07-08-AndICmp.ll | 10 |
2 files changed, 25 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index d15b6cf18b..fbd0d20071 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -3586,6 +3586,21 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { } } + { // (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C) + // where C is a power of 2 + Value *A, *B; + ConstantInt *C1, *C2; + ICmpInst::Predicate LHSCC, RHSCC; + if (match(&I, m_And(m_ICmp(LHSCC, m_Value(A), m_ConstantInt(C1)), + m_ICmp(RHSCC, m_Value(B), m_ConstantInt(C2))))) + if (C1 == C2 && LHSCC == RHSCC && LHSCC == ICmpInst::ICMP_ULT && + C1->getValue().isPowerOf2()) { + Instruction *NewOr = BinaryOperator::CreateOr(A, B); + InsertNewInstBefore(NewOr, I); + return new ICmpInst(LHSCC, NewOr, C1); + } + } + if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1)) { // (icmp1 A, B) & (icmp2 A, B) --> (icmp3 A, B) if (Instruction *R = AssociativeOpt(I, FoldICmpLogical(*this, RHS))) diff --git a/test/Transforms/InstCombine/2008-07-08-AndICmp.ll b/test/Transforms/InstCombine/2008-07-08-AndICmp.ll new file mode 100644 index 0000000000..c600241314 --- /dev/null +++ b/test/Transforms/InstCombine/2008-07-08-AndICmp.ll @@ -0,0 +1,10 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep icmp | count 1 +; PR2330 + +define i1 @foo(i32 %a, i32 %b) nounwind { +entry: + icmp ult i32 %a, 8 ; <i1>:0 [#uses=1] + icmp ult i32 %b, 8 ; <i1>:1 [#uses=1] + and i1 %1, %0 ; <i1>:2 [#uses=1] + ret i1 %2 +} |