From 83dc1c60aa7cccbfc3c187b42f86a75b68df1fa7 Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Thu, 20 Apr 2017 16:14:58 +0000 Subject: In SimplifyDemandedUseBits, use computeKnownBits directly to handle Constants Currently we don't explicitly process ConstantDataSequential, ConstantAggregateZero, or ConstantVector, or Undef before applying the Depth limit. Instead they occur after the depth check in the non-instruction path. For the constant types that we do handle, the code is replicated from computeKnownBits. This patch fixes the missing constant handling and the reduces the amount of code by just using computeKnownBits directly for any type of Constant. Differential Revision: https://reviews.llvm.org/D32123 llvm-svn: 300849 --- .../InstCombine/InstCombineSimplifyDemanded.cpp | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) (limited to 'llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp') diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp index 2f66bc7b8d6..c5328c77abb 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp @@ -117,27 +117,16 @@ Value *InstCombiner::SimplifyDemandedUseBits(Value *V, APInt DemandedMask, KnownOne.getBitWidth() == BitWidth && "Value *V, DemandedMask, KnownZero and KnownOne " "must have same BitWidth"); - const APInt *C; - if (match(V, m_APInt(C))) { - // We know all of the bits for a scalar constant or a splat vector constant! - KnownOne = *C; - KnownZero = ~KnownOne; - return nullptr; - } - if (isa(V)) { - // We know all of the bits for a constant! - KnownOne.clearAllBits(); - KnownZero.setAllBits(); + + if (isa(V)) { + computeKnownBits(V, KnownZero, KnownOne, Depth, CxtI); return nullptr; } KnownZero.clearAllBits(); KnownOne.clearAllBits(); - if (DemandedMask == 0) { // Not demanding any bits from V. - if (isa(V)) - return nullptr; + if (DemandedMask == 0) // Not demanding any bits from V. return UndefValue::get(VTy); - } if (Depth == 6) // Limit search depth. return nullptr; -- cgit v1.2.3