[llvm] [Loads] Respect UseDerefAtPointSemantics in isDerefAndAlignedPointer. (PR #123196)

[Florian Hahn via llvm-commits]

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@@ -168,7 +170,7 @@ static bool isDereferenceableAndAlignedPointer(
                                               Size, DL, CtxI, AC, DT, TLI,
                                               Visited, MaxDepth);
 
-  if (CtxI) {
+  if (CtxI && (!UseDerefAtPointSemantics || !V->canBeFreed())) {
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fhahn wrote:

My plan was first making things correct with the flag, then change the behavior for the attribute in assumes + langref change separately.

I can also pull it in here, although I still need to inspect the other uses of dereferenceable assumptions. 

https://github.com/llvm/llvm-project/pull/123196