[llvm] [DirectX] Remove lifetime intrinsics and run Dead Store Elimination (PR #152636)

[Deric C. via llvm-commits]

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@@ -78,6 +82,17 @@ static bool forwardHandleAccesses(Function &F, DominatorTree &DT) {
         case Intrinsic::dx_resource_handlefromimplicitbinding:
           processHandle(II, HandleMap);
           break;
+        // Note: Lifetime intrinsics do not show up as users of an Alloca.
+        // As a result we walk the whole function to find the lifetimes and
+        // store them so that we may delete the alloca matches
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Icohedron wrote:

When I use `->users()` on an `AllocaInst *` I do see lifetime intrinsic users. Is it just not the case in this pass for some reason?

https://github.com/llvm/llvm-project/pull/152636