[llvm] [GlobalISel] Combine (sext (trunc x)) to (sext_inreg x) (PR #131622)

[Matt Arsenault via llvm-commits]

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@@ -36,6 +36,20 @@ bool CombinerHelper::matchSextOfTrunc(const MachineOperand &MO,
   LLT DstTy = MRI.getType(Dst);
   LLT SrcTy = MRI.getType(Src);
 
+  // Combines without nsw trunc.
+  if (!(Trunc->getFlags() & MachineInstr::NoSWrap)) {
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arsenm wrote:

```suggestion
  if (!Trunc->getFlag(MachineInstr::NoSWrap)) {
```

https://github.com/llvm/llvm-project/pull/131622