[llvm] [AArch64][GlobalISel] Added pmull/pmull64 intrinsic support (PR #165740)

[David Green via llvm-commits]

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@@ -1809,6 +1809,10 @@ bool AArch64LegalizerInfo::legalizeIntrinsic(LegalizerHelper &Helper,
     return LowerBinOp(TargetOpcode::G_FMAXNUM);
   case Intrinsic::aarch64_neon_fminnm:
     return LowerBinOp(TargetOpcode::G_FMINNUM);
+  case Intrinsic::aarch64_neon_pmull:
+    return LowerBinOp(AArch64::G_PMULL); // Will prob need to be 64bit specific, /shrug
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davemgreen wrote:

Im not sure what needs to be 64bit. Probably best to drop the comment.

It can also do
```
case Intrinsic::aarch64_neon_pmull:
case Intrinsic::aarch64_neon_pmull64:
    return LowerBinOp(AArch64::G_PMULL);
```

https://github.com/llvm/llvm-project/pull/165740