[PATCH] D59227: [GlobalISel][Utils] Teach getConstantVRegVal how to look through trunc and z|sext

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added a comment.

In D59227#1427718 <https://reviews.llvm.org/D59227#1427718>, @qcolombet wrote:

> If we were to go down the road of allowing constants as MachineOperand, I would rather kill the G_CONSTANT and be smart about how we materialize them (unlike selection DAG). Now, the code churn to deal with that would be so bad (teaching every place that a MachineOperand may not be a vreg) that I don't think it makes sense.
>  I am somewhat sensible for the intrinsic argument since the generic passes don't look at them.


Right, I just want this for intrinsic arguments, and G_CONSTANT for anything else. Code looking at arbitrary instructions already need to worry about the possibility of some operand not being a register for G_PHI and DBG_VALUE anyway.


Repository:
  rL LLVM

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  https://reviews.llvm.org/D59227/new/

https://reviews.llvm.org/D59227