From 8e528100d210e225cee417229d94af91355118c0 Mon Sep 17 00:00:00 2001 From: Paul Redmond Date: Mon, 21 Jan 2013 21:57:20 +0000 Subject: Transform (sub 0, (zext bool to A)) to (sext bool to A) and (sub 0, (sext bool to A)) to (zext bool to A). Patch by Muhammad Ahmad Reviewed by Duncan Sands git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173093 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/InstCombine/InstCombineAddSub.cpp | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'lib') diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp index 03be8ef..c6d60d6 100644 --- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -1250,6 +1250,16 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { if (SimplifyDemandedInstructionBits(I)) return &I; + + // Fold (sub 0, (zext bool to B)) --> (sext bool to B) + if (C->isZero() && match(Op1, m_ZExt(m_Value(X)))) + if (X->getType()->isIntegerTy(1)) + return CastInst::CreateSExtOrBitCast(X, Op1->getType()); + + // Fold (sub 0, (sext bool to B)) --> (zext bool to B) + if (C->isZero() && match(Op1, m_SExt(m_Value(X)))) + if (X->getType()->isIntegerTy(1)) + return CastInst::CreateZExtOrBitCast(X, Op1->getType()); } -- cgit v1.1