[PGO] Use SourceFileName rather module name in PGOFuncName

In LTO or Thin-lto mode (though linker plugin), the module
names are of temp file names which are different for
different compilations. Using SourceFileName avoids the issue.
This should not change any functionality for current PGO as
all the current callers of getPGOFuncName() is before LTO.

Differential Revision: https://reviews.llvm.org/D56327

llvm-svn: 350671

llvm/lib/ProfileData/InstrProf.cpp

@@ -252,11 +252,12 @@ static StringRef stripDirPrefix(StringRef PathNameStr, uint32_t NumPrefix) {
 // data, its original linkage must be non-internal.
 std::string getPGOFuncName(const Function &F, bool InLTO, uint64_t Version) {
   if (!InLTO) {
-    StringRef FileName = (StaticFuncFullModulePrefix
-                              ? F.getParent()->getName()
-                              : sys::path::filename(F.getParent()->getName()));
-    if (StaticFuncFullModulePrefix && StaticFuncStripDirNamePrefix != 0)
-      FileName = stripDirPrefix(FileName, StaticFuncStripDirNamePrefix);
+    StringRef FileName(F.getParent()->getSourceFileName());
+    uint32_t StripLevel = StaticFuncFullModulePrefix ? 0 : (uint32_t)-1;
+    if (StripLevel < StaticFuncStripDirNamePrefix)
+      StripLevel = StaticFuncStripDirNamePrefix;
+    if (StripLevel)
+      FileName = stripDirPrefix(FileName, StripLevel);
     return getPGOFuncName(F.getName(), F.getLinkage(), FileName, Version);
   }