[BOLT][BAT] Add support for three-way split functions (llvm#93760)

In three-way split functions, if only .warm fragment is present, BAT incorrectly overwrites the map for .warm fragment by empty .cold fragment. Test Plan: updated register-fragments-bolt-symbols.s
Ericsson · Jul 5, 2024 · dc1da93 · dc1da93
1 parent 045e68f
commit dc1da93
Show file tree

Hide file tree

Showing 2 changed files with 7 additions and 0 deletions.
diff --git a/bolt/lib/Profile/BoltAddressTranslation.cpp b/bolt/lib/Profile/BoltAddressTranslation.cpp
@@ -129,6 +129,9 @@ void BoltAddressTranslation::write(const BinaryContext &BC, raw_ostream &OS) {
     LLVM_DEBUG(dbgs() << " Cold part\n");
     for (const FunctionFragment &FF :
          Function.getLayout().getSplitFragments()) {
+      // Skip empty fragments to avoid adding zero-address entries to maps.
+      if (FF.empty())
+        continue;
       ColdPartSource.emplace(FF.getAddress(), Function.getOutputAddress());
       Map.clear();
       for (const BinaryBasicBlock *const BB : FF)

diff --git a/bolt/test/X86/register-fragments-bolt-symbols.s b/bolt/test/X86/register-fragments-bolt-symbols.s
@@ -13,8 +13,12 @@
 # PREAGGWARM: B X:0 #chain.warm# 1 0
 # RUN: perf2bolt %t.warm.bolt -p %t.preagg.warm --pa -o %t.warm.fdata -w %t.warm.yaml \
 # RUN:   -v=1 | FileCheck %s --check-prefix=CHECK-BOLT-WARM
+# RUN: FileCheck %s --input-file %t.warm.fdata --check-prefix=CHECK-FDATA-WARM
+# RUN: FileCheck %s --input-file %t.warm.yaml --check-prefix=CHECK-YAML-WARM
 
 # CHECK-BOLT-WARM: marking chain.warm/1(*2) as a fragment of chain
+# CHECK-FDATA-WARM: chain
+# CHECK-YAML-WARM: chain
 
 # RUN: sed -i 's|chain|chain/2|g' %t.fdata
 # RUN: llvm-objcopy --localize-symbol=chain %t.main.o