[llvm] [DirectX] Implement `memcpy` in DXIL CBuffer Access pass (PR #144436)

[Deric C. via llvm-commits]

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@@ -161,7 +164,12 @@ static void replaceAccessesWithHandle(GlobalVariable *Global,
     }
 
     // Otherwise, walk users looking for a load...
-    ToProcess.append(Cur->user_begin(), Cur->user_end());
+    if (isa<GetElementPtrInst>(Cur) || isa<GEPOperator>(Cur)) {
+      ToProcess.append(Cur->user_begin(), Cur->user_end());
+      continue;
+    }
+
+    reportFatalInternalError("Unexpected user of Global");
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Icohedron wrote:

I wanted the error to appear even if clang was compiled without assertions enabled so that it won't silently generate incorrect code. Realistically this error should never occur unless someone manually wrote IR to try to use a cbuffer global using an instruction other than a load or memcpy.

https://github.com/llvm/llvm-project/pull/144436