[llvm] [GlobalISel] Support saturated truncate (PR #150219)

[David Green via llvm-commits]

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@@ -1838,6 +1841,15 @@ bool AArch64LegalizerInfo::legalizeIntrinsic(LegalizerHelper &Helper,
     return LowerTriOp(AArch64::G_UDOT);
   case Intrinsic::aarch64_neon_sdot:
     return LowerTriOp(AArch64::G_SDOT);
+  case Intrinsic::aarch64_neon_sqxtn: {
+    return LowerBinOp(TargetOpcode::G_TRUNC_SSAT_S);
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davemgreen wrote:

I think this needs to be unaryop, not binop. Can we make sure there are tests for it too?

https://github.com/llvm/llvm-project/pull/150219