[PATCH] D139491: [PowerPC] remove XXSWAPD after load from CP which is a splat value

[ChenZheng via Phabricator via llvm-commits]

shchenz added inline comments.


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Comment at: llvm/lib/Target/PowerPC/PPCMIPeephole.cpp:654
               .add(MI.getOperand(1));
+        } else if (Immed == 2 && TII->isLoadFromConstantPool(DefMI)) {
+          const Constant *C = TII->getConstantFromConstantPool(DefMI);
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Seems for swap `XXPERMDI` (Immed == 0 || Immed == 3), if the input is a splat constant value, there is also an opportunity to optimize the swap away?


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Comment at: llvm/lib/Target/PowerPC/PPCMIPeephole.cpp:672
       case PPC::VSPLTH:
       case PPC::XXSPLTW: {
         unsigned MyOpcode = MI.getOpcode();
----------------
Can we also improve these opcodes with splat constant inputs?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D139491/new/

https://reviews.llvm.org/D139491