[llvm] [MemProf] Include caller clone information in dot graph nodes (PR #150492)

[Teresa Johnson via llvm-commits]

https://github.com/teresajohnson created https://github.com/llvm/llvm-project/pull/150492

We already included the assigned clone of the callsite node's callee in
the dot graph after function assignment. This adds the same information
for the enclosing caller function to aid debugging.


>From a43e3097d9c8dce07e71bcd06b361ddbfad192ce Mon Sep 17 00:00:00 2001
From: Teresa Johnson <tejohnson at google.com>
Date: Thu, 24 Jul 2025 11:22:48 -0700
Subject: [PATCH] [MemProf] Include caller clone information in dot graph nodes

We already included the assigned clone of the callsite node's callee in
the dot graph after function assignment. This adds the same information
for the enclosing caller function to aid debugging.
---
 .../Transforms/IPO/MemProfContextDisambiguation.cpp    | 10 +++++-----
 llvm/test/ThinLTO/X86/memprof-basic.ll                 |  3 +++
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp b/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
index b803c97a7bd99..b1a4877f0675a 100644
--- a/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
+++ b/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
@@ -2073,14 +2073,14 @@ std::string IndexCallsiteContextGraph::getLabel(const FunctionSummary *Func,
                                                 unsigned CloneNo) const {
   auto VI = FSToVIMap.find(Func);
   assert(VI != FSToVIMap.end());
+  auto CallerName = getMemProfFuncName(VI->second.name(), CloneNo);
   if (isa<AllocInfo *>(Call))
-    return (VI->second.name() + " -> alloc").str();
+    return CallerName + " -> alloc";
   else {
     auto *Callsite = dyn_cast_if_present<CallsiteInfo *>(Call);
-    return (VI->second.name() + " -> " +
-            getMemProfFuncName(Callsite->Callee.name(),
-                               Callsite->Clones[CloneNo]))
-        .str();
+    return CallerName + " -> " +
+           getMemProfFuncName(Callsite->Callee.name(),
+                              Callsite->Clones[CloneNo]);
   }
 }
 
diff --git a/llvm/test/ThinLTO/X86/memprof-basic.ll b/llvm/test/ThinLTO/X86/memprof-basic.ll
index c5eedb2841b8c..67ae64f64479f 100644
--- a/llvm/test/ThinLTO/X86/memprof-basic.ll
+++ b/llvm/test/ThinLTO/X86/memprof-basic.ll
@@ -52,6 +52,7 @@
 ; RUN:	cat %t.ccg.postbuild.dot | FileCheck %s --check-prefix=DOT
 ;; We should have cloned bar, baz, and foo, for the cold memory allocation.
 ; RUN:	cat %t.ccg.cloned.dot | FileCheck %s --check-prefix=DOTCLONED
+; RUN:	cat %t.ccg.clonefuncassign.dot | FileCheck %s --check-prefix=DOTFUNCASSIGN
 
 ; RUN: llvm-dis %t.out.1.4.opt.bc -o - | FileCheck %s --check-prefix=IR
 
@@ -370,6 +371,8 @@ attributes #0 = { noinline optnone }
 ; DOTCLONED: 	Node[[BAR2]] [shape=record,tooltip="N[[BAR2]] ContextIds: 2",fillcolor="cyan",color="blue",style="filled,bold,dashed",label="{OrigId: Alloc0\n_Z3barv -\> alloc}"];
 ; DOTCLONED: }
 
+; DOTFUNCASSIGN: _Z3bazv.memprof.1 -\> _Z3barv.memprof.1
+; DOTFUNCASSIGN: _Z3barv.memprof.1 -\> alloc
 
 ; DISTRIB: ^[[BAZ:[0-9]+]] = gv: (guid: 1807954217441101578, {{.*}} callsites: ((callee: ^[[BAR:[0-9]+]], clones: (0, 1)
 ; DISTRIB: ^[[FOO:[0-9]+]] = gv: (guid: 8107868197919466657, {{.*}} callsites: ((callee: ^[[BAZ]], clones: (0, 1)