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

[Matt Arsenault 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 - %s | FileCheck %s
+
+--- |
+  define double @dyn_extract_v7f64_v_v(<7 x double> %vec, i32 %sel) #0 {
+  entry:
+    %ext = extractelement <7 x double> %vec, i32 %sel
+    ret double %ext
+  }
+
+  attributes #0 = { "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,10" "target-cpu"="gfx900" "uniform-work-group-size"="false" }
+...
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arsenm wrote:

Don't think you need the IR section 

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