[PATCH] D85288: [PowerPC] Remove implicit use register after transformToImmFormFedByLI()

[Kai Luo via Phabricator via llvm-commits]

lkail added a comment.

In D85288#2687705 <https://reviews.llvm.org/D85288#2687705>, @shchenz wrote:

>> implicit $x5 is in the explicit operand list.
>
> Should it be an issue that the `implicit $x5` should not be in the explicit operand list? Since when we have `implicit $x5` as an explicit operand?

Take

  renamable $x5 = LI8 2
  renamable $x4 = exact SRD killed renamable $x4, killed renamable $r5, implicit $x5

converted to

  renamable $x5 = LI8 2
  renamable $x4 = exact RLDICL killed renamable $x4, 62, 2,  implicit killed $x5

as an example.
`SRD` has 2 explicit operands. When `SRD` is converted to `RLDICL` via setting a new MCID and `RLDICL` has 3 explicit operands, so `implicit $x5` is within `RLDICL`'s explicit operands. Later `replaceInstrOperandWithImm` is called and `killed renamable $r5` is converted to imm `62`. With origin impl, this instruction currently is

  renamable $x4 = exact RLDICL killed renamable $x4, 62, implicit killed $x5

Then `achineInstrBuilder(*MI.getParent()->getParent(), MI).addImm(ME);` is called. Notice that `addImm`'s implementation will traverse the operand list and find a location explicit operand goes before implicit operand, so for now this instruction is

  renamable $x4 = exact RLDICL killed renamable $x4, 62, 2,  implicit killed $x5


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D85288/new/

https://reviews.llvm.org/D85288