Some cases may be transformed into 32 bit splats before hitting the boolean statement, which may cause incorrect behaviour and provide XXSPLTI32DX with the incorrect values of splat. The condition was reversed so that the shortcut prevents this problem.
Differential Revision: https://reviews.llvm.org/D95634
If the APInt returned by BuildVectorSDNode::isConstantSplat() is narrower than
64 bits, the result produced by XXSPLTI32DX is incorrect. The result returned
by the function appears to be incorrect and we'll investigate/fix it in a
follow-up commit. However, since this causes miscompiles, we must
temporarily disable emitting this instruction for such values.
Exploits the instruction xxsplti32dx.
It can be used to materialize any 64 bit scalar/vector splat by using two instances, one for the upper 32 bits and the other for the lower 32 bits. It should not materialize the cases which can be materialized by using the instruction xxspltidp.
Differential Revision: https://https://reviews.llvm.org/D90173
This patch aims to exploit the xxsplti32dx XT, IX, IMM32 instruction when lowering VECTOR_SHUFFLEs.
We implement lowerToXXSPLTI32DX when lowering vector shuffles to check if:
- Element size is 4 bytes
- The RHS is a constant vector (and constant splat of 4-bytes)
- The shuffle mask is a suitable mask for the XXSPLTI32DX instruction where it is one of the 32 masks:
<0, 4-7, 2, 4-7>
<4-7, 1, 4-7, 3>
Differential Revision: https://reviews.llvm.org/D83245
Albion Fung