diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 38551dbba29..245cb414ca9 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -18492,6 +18492,39 @@ static bool combineRedundantDWordShuffle(SDValue N, MutableArrayRef<int> Mask, return false; continue; + + case X86ISD::UNPCKL: + case X86ISD::UNPCKH: + // For either i8 -> i16 or i16 -> i32 unpacks, we can combine a dword + // shuffle into a preceding word shuffle. + if (V.getValueType() != MVT::v16i8 && V.getValueType() != MVT::v8i16) + return false; + + // Search for a half-shuffle which we can combine with. + unsigned CombineOp = + V.getOpcode() == X86ISD::UNPCKL ? X86ISD::PSHUFLW : X86ISD::PSHUFHW; + if (V.getOperand(0) != V.getOperand(1) || + !V->isOnlyUserOf(V.getOperand(0).getNode())) + return false; + V = V.getOperand(0); + do { + switch (V.getOpcode()) { + default: + return false; // Nothing to combine. + + case X86ISD::PSHUFLW: + case X86ISD::PSHUFHW: + if (V.getOpcode() == CombineOp) + break; + + // Fallthrough! + case ISD::BITCAST: + V = V.getOperand(0); + continue; + } + break; + } while (V.hasOneUse()); + break; } // Break out of the loop if we break out of the switch. break; @@ -18508,7 +18541,7 @@ static bool combineRedundantDWordShuffle(SDValue N, MutableArrayRef<int> Mask, SmallVector<int, 4> VMask = getPSHUFShuffleMask(V); for (int &M : Mask) M = VMask[M]; - V = DAG.getNode(X86ISD::PSHUFD, DL, V.getValueType(), V.getOperand(0), + V = DAG.getNode(V.getOpcode(), DL, V.getValueType(), V.getOperand(0), getV4X86ShuffleImm8ForMask(Mask, DAG)); // It is possible that one of the combinable shuffles was completely absorbed |
