[llvm] [DSE] Apply initializes attribute to DSE (PR #107282)

[Arthur Eubanks via llvm-commits]

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@@ -2232,8 +2366,11 @@ DSEState::eliminateDeadDefs(const MemoryLocationWrapper &KillingLocWrapper) {
     }
     MemoryDefWrapper DeadDefWrapper(
         cast<MemoryDef>(DeadAccess),
-        getLocForInst(cast<MemoryDef>(DeadAccess)->getMemoryInst()));
-    MemoryLocationWrapper &DeadLocWrapper = *DeadDefWrapper.DefinedLocation;
+        getLocForInst(cast<MemoryDef>(DeadAccess)->getMemoryInst(),
+                      /*ConsiderInitializesAttr=*/false));
+    assert(DeadDefWrapper.DefinedLocations.size() == 1);
+    MemoryLocationWrapper &DeadLocWrapper =
+        DeadDefWrapper.DefinedLocations.front();
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aeubanks wrote:

I'm not 100% sure what's going on here, but it seems weird that we have two modes for `MemoryDefWrapper`, a single MemoryLocation version here and a multiple MemoryLocation below. is there any way to make this a little less hacked together? why does this have to be a single MemoryLocation?

https://github.com/llvm/llvm-project/pull/107282