[llvm] [IR][CodeGen] Specify llvm.gcroot contents are an opaque zero-initialized blob (PR #222333)

[via llvm-commits]

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@@ -159,7 +158,7 @@ Constant *ShadowStackGCLoweringImpl::GetFrameMap(Function &F,
   Type *Int32Ty = Type::getInt32Ty(F.getContext());
 
   Constant *BaseElts[] = {
-      ConstantInt::get(Int32Ty, FrameSizeInPtrs, false),
+      ConstantInt::get(Int32Ty, Roots.size(), false),
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isuckatcs wrote:

A lot of these parts of the diff is restoring the original behavior. I'd rather base this change on top of the revert  commit. That way it becomes more obvious what changes this commit brings.

https://github.com/llvm/llvm-project/pull/222333