[llvm] [NFCI] replace getValueType with new getGlobalSize query (PR #177186)

[Nikita Popov via llvm-commits]

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@@ -170,6 +171,9 @@ class GlobalVariable : public GlobalObject, public ilist_node<GlobalVariable> {
   /// it isn't explicitly set.
   LLVM_ABI void replaceInitializer(Constant *InitVal);
 
+  /// Get the size of this global variable in bytes.
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nikic wrote:

I'd add a comment here that this may be a minimum size if the global is a declaration or a replaceable definition.

https://github.com/llvm/llvm-project/pull/177186