[llvm] [MCP] Skip invalidating def constant regs during forward propagation (PR #111129)

[Vladimir Radosavljevic via llvm-commits]

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@@ -0,0 +1,19 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=aarch64-none-linux-gnu -run-pass machine-cp -verify-machineinstrs -o - %s | FileCheck %s
+
+---
+name: test
+body: |
+  bb.0:
+    liveins: $w2
+    ; CHECK-LABEL: name: test
+    ; CHECK: liveins: $w2
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: dead $wzr = SUBSWri killed renamable $w2, 0, 0, implicit-def $nzcv
+    ; CHECK-NEXT: renamable $w0 = COPY $wzr
+    ; CHECK-NEXT: RET_ReallyLR implicit killed $w0
+    renamable $w1 = COPY $wzr
+    dead $wzr = SUBSWri killed renamable $w2, 0, 0, implicit-def $nzcv
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vladimirradosavljevic wrote:

Removed dead flag.

https://github.com/llvm/llvm-project/pull/111129