[llvm] [CGData] Lazy loading support for stable function map (PR #151660)

[Kyungwoo Lee via llvm-commits]

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@@ -104,17 +104,39 @@ void StableFunctionMapRecord::serialize(
       Writer.OS.tell() - NamesByteSizeOffset - sizeof(NamesByteSizeOffset);
   PatchItems.emplace_back(NamesByteSizeOffset, &NamesByteSize, 1);
 
-  // Write StableFunctionEntries whose pointers are sorted.
+  // Write StableFunctionEntries. The structure is:
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kyulee-com wrote:

It might worth commenting the overall layout at the top of function or header, including the name section above as it now becomes fairly complex.

https://github.com/llvm/llvm-project/pull/151660