[llvm] [RegisterCoalescer] Materialize undef subrange PHI inputs (PR #204867)

[Lukas Sommer via llvm-commits]

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@@ -10,7 +10,7 @@
 # BB (bb.25)
 #
 # GCN-LABEL: bb.6:
-# GCN: successors: %bb.7(0x{{[0-9]+}}), %bb.18(0x{{[0-9]+}})
+# GCN: successors: %bb.[[EDGE:[0-9]+]](0x{{[0-9]+}}), %bb.18(0x{{[0-9]+}})
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sommerlukas wrote:

Doesn't this weaken the test? We define `EDGE` here, so it could be a completely different edge.

https://github.com/llvm/llvm-project/pull/204867