[MemProf] Fix when CallStackTrie is a single chain with multi alloc type

Author: lifengxiang1025

llvm/lib/Analysis/MemoryProfileInfo.cpp

@@ -244,11 +244,16 @@ 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));
+  if (buildMIBNodes(Alloc, Ctx, MIBCallStack, MIBNodes,
+                    Alloc->Callers.size() > 1)) {
+    assert(MIBCallStack.size() == 1 &&
+           "Should only be left with Alloc's location in stack");
+    CI->setMetadata(LLVMContext::MD_memprof, MDNode::get(Ctx, MIBNodes));
+  } else
+    // If there exists corner case that CallStackTrie is one chain and all node
+    // with multi alloc type, Conservatively give it non-cold allocation type.
+    // FIXME: Avoid this case before memory profile created.
+    addAllocTypeAttribute(Ctx, CI, AllocationType::NotCold);
   return true;
 }