Eli Friedman e68e4cbcc5 [GlobalISel] Change representation of shuffle masks in MachineOperand.
We're planning to remove the shufflemask operand from ShuffleVectorInst
(D72467); fix GlobalISel so it doesn't depend on that Constant.

The change to prelegalizercombiner-shuffle-vector.mir happens because
the input contains a literal "-1" in the mask (so the parser/verifier
weren't really handling it properly). We now treat it as equivalent to
"undef" in all contexts.

Differential Revision: https://reviews.llvm.org/D72663
2020-01-13 16:55:41 -08:00
..