[PATCH] D139813: [PowerPC] Improve materialization for immediates which is almost a 32 bit splat.

[Esme Yi via Phabricator via llvm-commits]

Esme added inline comments.


================
Comment at: llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp:1334
+  // splat of a 32 bit immediate.
+  if (InstCntDirect > 4) {
+    uint32_t Hi16OfHi32 = (Hi_32(Imm) >> 16) & 0xffff;
----------------
shchenz wrote:
> For compile time concern, since the 1 instruction patterns for `Imm & 0xffffffff00000000` are simple, can we move the new code before line 1318 and do some simple check for 1 instruction pattern in `selectI64ImmDirect`? 
Sorry I didn't quite understand this comment.
`Imm & 0xffffffff00000000` always takes more than 1 instruction because it is impossible to match the 1-instruction-pattern:
```
  // 1-1) Patterns : {zeros}{15-bit valve}
  //                 {ones}{15-bit valve}

  // 1-2) Patterns : {zeros}{15-bit valve}{16 zeros}
  //                 {ones}{15-bit valve}{16 zeros}
```


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D139813/new/

https://reviews.llvm.org/D139813