[PATCH] D108581: [CSPGO] Fix lost IRPGOFlag in CSPGO instrumentation

[Rong Xu via Phabricator via llvm-commits]

xur marked 3 inline comments as done.
xur added inline comments.


================
Comment at: llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp:468
     createProfileFileNameVar(M, InstrProfileOutput);
-    createIRLevelProfileFlagVar(M, /* IsCS */ true, PGOInstrumentEntry);
+    appendToCompilerUsed(
+        M, createIRLevelProfileFlagVar(M, /* IsCS */ true, PGOInstrumentEntry));
----------------
MaskRay wrote:
> Add a comment like:
> 
> The variable in a comdat may be discarded by LTO. Ensure the declaration will be retained.
> 
> This raises the question: Is llvm.compiler.used allowed to reference a declaration (previously a non-prevailing definition due to comdat selection)? ISTM this should be allowed.
comment added.

For the question:
At the time of appending to llvm.compiler.used, this is a definition (not a decl). I don't see any problem add it to the list.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108581/new/

https://reviews.llvm.org/D108581