[PATCH] D39446: [PGO] Detect more structural changes with the stable hash

[Vedant Kumar via Phabricator via cfe-commits]

vsk added inline comments.


================
Comment at: lib/CodeGen/CodeGenPGO.cpp:244
+  DEFINE_NESTABLE_TRAVERSAL(CXXTryStmt)
+  DEFINE_NESTABLE_TRAVERSAL(CXXCatchStmt)
+
----------------
arphaman wrote:
> What about `ObjCAtTryStmt`?
I thought about this, but: we don't place a counter on ObjC at-try's, so it seems a bit moot to invalidate the profile if we see one change.


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Comment at: lib/CodeGen/CodeGenPGO.cpp:321
+        return PGOHash::ReturnStmt;
+      case Stmt::CXXThrowExprClass:
+        return PGOHash::ThrowExpr;
----------------
arphaman wrote:
> Might as well include the `ObjCAtThrowStmt` as well.
If profiling at-try isn't very important, I'm not sure the hash should be sensitive to at-throw either. I do see situations where it could be helpful, but IMO the potential benefit is outweighed by having extra invalidations.


https://reviews.llvm.org/D39446