[llvm] [MemProf] Fix when CallStackTrie is a single chain with multi alloc type (PR #79433)

[via llvm-commits]

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@@ -244,12 +244,18 @@ bool CallStackTrie::buildAndAttachMIBMetadata(CallBase *CI) {
   MIBCallStack.push_back(AllocStackId);
   std::vector<Metadata *> MIBNodes;
   assert(!Alloc->Callers.empty() && "addCallStack has not been called yet");
-  buildMIBNodes(Alloc, Ctx, MIBCallStack, MIBNodes,
-                /*CalleeHasAmbiguousCallerContext=*/true);
-  assert(MIBCallStack.size() == 1 &&
-         "Should only be left with Alloc's location in stack");
-  CI->setMetadata(LLVMContext::MD_memprof, MDNode::get(Ctx, MIBNodes));
-  return true;
+  if (buildMIBNodes(Alloc, Ctx, MIBCallStack, MIBNodes,
+                    Alloc->Callers.size() > 1)) {
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lifengxiang1025 wrote:

After updaing code, now if CallStackTrie has a single chain to leaf with multi alloc type, buildMIBNodes will return false and we'll conservatively give this alloc non-cold allocation type.

https://github.com/llvm/llvm-project/pull/79433