[llvm] [TwoAddressInstruction] Propagate undef flags for partial defs (PR #79286)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,134 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 4
+# RUN: llc -mtriple=amdgcn-mesa-mesa3d -mcpu=gfx900 -early-live-intervals -run-pass=liveintervals -run-pass=twoaddressinstruction -verify-machineinstrs -o - | FileCheck %s
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jayfoad wrote:

```suggestion
# RUN: llc -mtriple=amdgcn-mesa-mesa3d -mcpu=gfx900 -early-live-intervals -run-pass=liveintervals -run-pass=twoaddressinstruction -verify-machineinstrs -o - %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/79286