diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/TargetLowering.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/TargetLowering.cpp | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp index e21bf48c35..a0ec7ddd6f 100644 --- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -1353,7 +1353,6 @@ TargetLowering::SimplifySetCC(MVT VT, SDValue N0, SDValue N1, } } -#if 0 // If the LHS is '(and load, const)', the RHS is 0, // the test is for equality or unsigned, and all 1 bits of the const are // in the same partial word, see if we can shorten the load. @@ -1364,17 +1363,23 @@ TargetLowering::SimplifySetCC(MVT VT, SDValue N0, SDValue N1, isa<ConstantSDNode>(N0.getOperand(1))) { LoadSDNode *Lod = cast<LoadSDNode>(N0.getOperand(0)); uint64_t Mask = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue(); + uint64_t bestMask = 0; unsigned bestWidth = 0, bestOffset = 0; - if (!Lod->isVolatile()) { + if (!Lod->isVolatile() && Lod->isUnindexed()) { unsigned origWidth = N0.getValueType().getSizeInBits(); + // We can narrow (e.g.) 16-bit extending loads on 32-bit target to + // 8 bits, but have to be careful... + if (Lod->getExtensionType() != ISD::NON_EXTLOAD) + origWidth = Lod->getMemoryVT().getSizeInBits(); for (unsigned width = origWidth / 2; width>=8; width /= 2) { uint64_t newMask = (1ULL << width) - 1; for (unsigned offset=0; offset<origWidth/width; offset++) { if ((newMask & Mask)==Mask) { if (!TD->isLittleEndian()) bestOffset = (origWidth/width - offset - 1) * (width/8); - else + else bestOffset = (uint64_t)offset * (width/8); + bestMask = Mask >> (offset * 8); bestWidth = width; break; } @@ -1385,7 +1390,6 @@ TargetLowering::SimplifySetCC(MVT VT, SDValue N0, SDValue N1, if (bestWidth) { MVT newVT = MVT::getIntegerVT(bestWidth); if (newVT.isRound()) { - uint64_t bestMask = Mask >> (bestOffset * 8); MVT PtrType = Lod->getOperand(1).getValueType(); SDValue Ptr = Lod->getBasePtr(); if (bestOffset != 0) @@ -1402,7 +1406,6 @@ TargetLowering::SimplifySetCC(MVT VT, SDValue N0, SDValue N1, } } } -#endif // If the LHS is a ZERO_EXTEND, perform the comparison on the input. if (N0.getOpcode() == ISD::ZERO_EXTEND) { |