[llvm] [SelectionDAG] Preserve volatile undef stores. (PR #99918)

[Matt Arsenault via llvm-commits]

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@@ -153,7 +153,7 @@ define void @func_use_lds_global_constexpr_cast() {
 ; GISEL-NEXT:    s_setpc_b64 s[30:31]
 ; GISEL-NEXT:  .LBB1_2:
 ; GISEL-NEXT:    s_endpgm
-  store volatile i32 ptrtoint (ptr addrspace(3) @lds to i32), ptr addrspace(1) poison, align 4
+  store i32 ptrtoint (ptr addrspace(3) @lds to i32), ptr addrspace(1) poison, align 4
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arsenm wrote:

Keep volatile or make store to null or other filler pointer 

https://github.com/llvm/llvm-project/pull/99918