[MemProf] Include caller clone information in dot graph nodes

[teresajohnson]

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.

[llvmbot]

@llvm/pr-subscribers-lto

@llvm/pr-subscribers-llvm-transforms

Author: Teresa Johnson (teresajohnson)

Changes

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.

---

Full diff: https://github.com/llvm/llvm-project/pull/150492.diff

2 Files Affected:

• (modified) llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp (+5-5)
• (modified) llvm/test/ThinLTO/X86/memprof-basic.ll (+3)

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)

[snehasish]

nit: Spelling out the type as std::string makes it easier to reason about the operations that follow.

[teresajohnson]

done