[BOLT][NFC] Don't assign YAML profile to functions with no CFG

[aaupov]

YAML profile for non-simple functions without CFG is

1. useless for optimizations,
2. can't be attached, similar to fdata profile,
3. would be reported as invalid/stale even if the profile is valid.

Don't attempt to attach the profile in this case, aligning the behavior
to DataReader.

Test Plan: added yaml-non-simple.test

[llvmbot]

@llvm/pr-subscribers-bolt

Author: Amir Ayupov (aaupov)

Changes

YAML profile for non-simple functions without CFG is

1. useless for optimizations,
2. can't be attached, similar to fdata profile,
3. would be reported as invalid/stale even if the profile is valid.

Don't attempt to attach the profile in this case, aligning the behavior
to DataReader.

---

Full diff: https://github.com/llvm/llvm-project/pull/92487.diff

1 Files Affected:

• (modified) bolt/lib/Profile/YAMLProfileReader.cpp (+3)

diff --git a/bolt/lib/Profile/YAMLProfileReader.cpp b/bolt/lib/Profile/YAMLProfileReader.cpp
index 978a7cadfe798..29d94067f459f 100644
--- a/bolt/lib/Profile/YAMLProfileReader.cpp
+++ b/bolt/lib/Profile/YAMLProfileReader.cpp
@@ -99,6 +99,9 @@ bool YAMLProfileReader::parseFunctionProfile(
       FuncRawBranchCount += YamlSI.Count;
   BF.setRawBranchCount(FuncRawBranchCount);
 
+  if (BF.empty())
+    return true;
+
   if (!opts::IgnoreHash &&
       YamlBF.Hash != BF.computeHash(IsDFSOrder, HashFunction)) {
     if (opts::Verbosity >= 1)

[dcci]

Can you trigger this somehow from YAML? Like adding a diagnostic and checking if it's hit?

[dcci]

LGTM, thanks.