[Profile] Do not assign counters to functions without bodies

The root cause of the issues reported in D32406 and D34680 is that clang
instruments functions without bodies. Make it stop doing that, and also
teach it how to use old (incorrectly generated) profiles without
crashing.

llvm-svn: 306883

3 files changed, 33 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenPGO.cpp b/clang/lib/CodeGen/CodeGenPGO.cpp
index 9e193531d0f..c3d66c1dabc 100644
--- a/clang/lib/CodeGen/CodeGenPGO.cpp
+++ b/clang/lib/CodeGen/CodeGenPGO.cpp
@@ -617,6 +617,9 @@ uint64_t PGOHash::finalize() {
 
 void CodeGenPGO::assignRegionCounters(GlobalDecl GD, llvm::Function *Fn) {
   const Decl *D = GD.getDecl();
+  if (!D->hasBody())
+    return;
+
   bool InstrumentRegions = CGM.getCodeGenOpts().hasProfileClangInstr();
   llvm::IndexedInstrProfReader *PGOReader = CGM.getPGOReader();
   if (!InstrumentRegions && !PGOReader)
diff --git a/clang/test/Profile/Inputs/cxx-missing-bodies.proftext b/clang/test/Profile/Inputs/cxx-missing-bodies.proftext
new file mode 100644
index 00000000000..c07f297f74d
--- /dev/null
+++ b/clang/test/Profile/Inputs/cxx-missing-bodies.proftext
@@ -0,0 +1,9 @@
+??_GA@@UAEPAXI@Z
+1
+1
+1
+
+??_DA@@QAEXXZ
+1
+1
+1
diff --git a/clang/test/Profile/cxx-missing-bodies.cpp b/clang/test/Profile/cxx-missing-bodies.cpp
new file mode 100644
index 00000000000..fe926b3b218
--- /dev/null
+++ b/clang/test/Profile/cxx-missing-bodies.cpp
@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -emit-llvm %s -std=c++11 -S -emit-llvm -o - -triple=i386-pc-win32 -fno-rtti -fprofile-instrument=clang | FileCheck %s --check-prefix=GEN
+//
+// Don't crash when presented profile data for functions without bodies:
+// RUN: llvm-profdata merge %S/Inputs/cxx-missing-bodies.proftext -o %t.profdata
+// RUN: %clang_cc1 -emit-llvm %s -std=c++11 -S -emit-llvm -o /dev/null -triple=i386-pc-win32 -fno-rtti -fprofile-instrument-use-path=%t.profdata -w
+
+// GEN-NOT: __profn{{.*}}??_GA@@UAEPAXI@Z
+// GEN-NOT: __profn{{.*}}??_DA@@QAEXXZ
+
+struct A {
+  virtual ~A();
+};
+struct B : A {
+  virtual ~B();
+};
+
+B::~B() {}
+
+void foo() {
+  B c;
+}