[llvm] [InferAddressSpaces] Extend undef pointer operand support to phi inst (PR #159548)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,36 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -S -passes=infer-address-spaces %s | FileCheck %s
+
+define void @phi_undef(ptr addrspace(1) %arg, <2 x ptr addrspace(1)> %arg1) {
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arsenm wrote:

Yes, I suppose it's not adding that much. Given that we are only rewriting the undefs to a different type, this transform should be undef safe anyway (not entirely sure that is true if we're making use of assume calls)

https://github.com/llvm/llvm-project/pull/159548