[llvm] [AMDGPU][SplitModule] Handle !callees metadata (PR #108802)

[Matt Arsenault via llvm-commits]

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@@ -476,12 +482,38 @@ void SplitGraph::Node::visitAllDependencies(
   }
 }
 
+/// Checks if \p I has MD_callees and if it does, parse it and put the function
+/// in \p Callees.
+///
+/// \returns true if there was metadata and it was parsed correctly. false if
+/// there was no MD or if it contained unknown entries and parsing failed.
+/// If this returns false, \p Callees will contain incomplete information
+/// and must not be used.
+static bool handleCalleesMD(const Instruction &I,
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arsenm wrote:

Still think the call graph analysis should be handling this 

https://github.com/llvm/llvm-project/pull/108802