[llvm] [InstCombine][AMDGPU] Disable PtrReplacer when select has mismatch AS. (PR #98456)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,48 @@
+; RUN: opt -S -mtriple=amdgcn-amd-amdhsa -passes=instcombine %s | FileCheck %s
+
+; Variant of select with addrspacecast in one branch on path to root alloca (ic opt is then disabled)
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arsenm wrote:

Did this used to crash or something? 

https://github.com/llvm/llvm-project/pull/98456