[PATCH] D16258: [PGO] Profile Summary Index profile writer and reader support

[Rong Xu via llvm-commits]

xur added inline comments.

================
Comment at: include/llvm/ProfileData/InstrProf.h:751
@@ +750,3 @@
+  // Reserved fields for future
+  uint64_t Reserved[5];
+  /// Number of Cutoff entries
----------------
vsk wrote:
> I'm not sure about this Reserved field. IMO any new future functionality should come with a format version bump, even if the on-disk layout stays the same. That means we can teach the reader to skip straight to NumEntries for v4 files.
Do we need to use uint64_t for TotalNumFunctions and TotalNumBlocks. Will uint32_t enough? 


http://reviews.llvm.org/D16258