CodeGen: Improve warnings about uninstrumented files when profiling

Improve the warning when building with -fprofile-instr-use and a file
appears not to have been profiled at all. This keys on whether a
function is defined in the main file or not to avoid false negatives
when one includes a header with functions that have been profiled.

llvm-svn: 211760

3 files changed, 39 insertions, 0 deletions

diff --git a/clang/test/Profile/Inputs/c-unprofiled.proftext b/clang/test/Profile/Inputs/c-unprofiled.proftext
new file mode 100644
index 00000000000..d2ef7ae301d
--- /dev/null
+++ b/clang/test/Profile/Inputs/c-unprofiled.proftext
@@ -0,0 +1,10 @@
+function_in_header
+10
+2
+1
+0
+
+main
+0
+1
+1
diff --git a/clang/test/Profile/Inputs/profiled_header.h b/clang/test/Profile/Inputs/profiled_header.h
new file mode 100644
index 00000000000..fa649d4b599
--- /dev/null
+++ b/clang/test/Profile/Inputs/profiled_header.h
@@ -0,0 +1,3 @@
+void function_in_header(int i) {
+  if (i) {}
+}
diff --git a/clang/test/Profile/c-unprofiled.c b/clang/test/Profile/c-unprofiled.c
new file mode 100644
index 00000000000..275cd2d1458
--- /dev/null
+++ b/clang/test/Profile/c-unprofiled.c
@@ -0,0 +1,26 @@
+// Test that unprofiled files are recognized. Here, we have two functions in the
+// profile, main() and function_in_header, but we use the profile on a file that
+// has the profile-less some_unprofiled_function so that the only profiled code
+// in #included in a header.
+
+// FIXME: It would be nice to use -verify here instead of FileCheck, but -verify
+// doesn't play well with warnings that have no line number.
+
+// RUN: llvm-profdata merge %S/Inputs/c-unprofiled.proftext -o %t.profdata
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.9 -main-file-name c-unprofiled.c -I %S/Inputs/ %s -o /dev/null -emit-llvm -fprofile-instr-use=%t.profdata -Wprofile-instr-unprofiled 2>&1 | FileCheck %s
+
+// CHECK: warning: no profile data available for file "c-unprofiled.c"
+
+#include "profiled_header.h"
+
+#ifdef GENERATE_OUTDATED_DATA
+int main(int argc, const char *argv[]) {
+  function_in_header(0);
+  return 0;
+}
+#else
+void some_unprofiled_function(int i) {
+  if (i)
+    function_in_header(i);
+}
+#endif