Mask[1] == SM_SentinelUndef ? DAG.getUNDEF(MVT::v2f64) : V1,
DAG.getConstant(SHUFPDMask, DL, MVT::i8));
}
- assert(Mask[0] >= 0 && Mask[0] < 2 && "Non-canonicalized blend!");
- assert(Mask[1] >= 2 && "Non-canonicalized blend!");
+ assert(Mask[0] >= 0 && "No undef lanes in multi-input v2 shuffles!");
+ assert(Mask[1] >= 0 && "No undef lanes in multi-input v2 shuffles!");
+ assert(Mask[0] < 2 && "We sort V1 to be the first input.");
+ assert(Mask[1] >= 2 && "We sort V2 to be the second input.");
- // If we have a single input, insert that into V1 if we can do so cheaply.
- if ((Mask[0] >= 2) + (Mask[1] >= 2) == 1) {
- if (SDValue Insertion = lowerVectorShuffleAsElementInsertion(
- DL, MVT::v2f64, V1, V2, Mask, Zeroable, Subtarget, DAG))
- return Insertion;
- // Try inverting the insertion since for v2 masks it is easy to do and we
- // can't reliably sort the mask one way or the other.
- int InverseMask[2] = {Mask[0] < 0 ? -1 : (Mask[0] ^ 2),
- Mask[1] < 0 ? -1 : (Mask[1] ^ 2)};
- if (SDValue Insertion = lowerVectorShuffleAsElementInsertion(
- DL, MVT::v2f64, V2, V1, InverseMask, Zeroable, Subtarget, DAG))
- return Insertion;
- }
+ // When loading a scalar and then shuffling it into a vector we can often do
+ // the insertion cheaply.
+ if (SDValue Insertion = lowerVectorShuffleAsElementInsertion(
+ DL, MVT::v2f64, V1, V2, Mask, Zeroable, Subtarget, DAG))
+ return Insertion;
+ // Try inverting the insertion since for v2 masks it is easy to do and we
+ // can't reliably sort the mask one way or the other.
+ int InverseMask[2] = {Mask[0] < 0 ? -1 : (Mask[0] ^ 2),
+ Mask[1] < 0 ? -1 : (Mask[1] ^ 2)};
+ if (SDValue Insertion = lowerVectorShuffleAsElementInsertion(
+ DL, MVT::v2f64, V2, V1, InverseMask, Zeroable, Subtarget, DAG))
+ return Insertion;
// Try to use one of the special instruction patterns to handle two common
// blend patterns if a zero-blend above didn't work.