[llvm] [AMDGPU] Only insert intrinsic declarations when needed (PR #117998)

[Jay Foad via llvm-commits]

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@@ -38,6 +38,7 @@ using StackVector = SmallVector<StackEntry, 16>;
 
 class SIAnnotateControlFlow {
 private:
+  Function *F;
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jayfoad wrote:

This one is always initialized by the constructor, `F(&F)`

https://github.com/llvm/llvm-project/pull/117998