[ProfileData] PR33517: Check for failure of symtab creation

With PR33517, it became apparent that symbol table creation can fail
when presented with malformed inputs. This patch makes that sort of
error detectable, so llvm-cov etc. can fail more gracefully.

Specifically, we now check that function names within the symbol table
aren't empty.

Testing: check-{llvm,clang,profile}, some unit test updates.
llvm-svn: 305765

1 files changed, 8 insertions, 4 deletions

diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index c9b82c303e3..005061c4f06 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -330,14 +330,15 @@ GlobalVariable *createPGOFuncNameVar(Function &F, StringRef PGOFuncName) {
   return createPGOFuncNameVar(*F.getParent(), F.getLinkage(), PGOFuncName);
 }
 
-void InstrProfSymtab::create(Module &M, bool InLTO) {
+Error InstrProfSymtab::create(Module &M, bool InLTO) {
   for (Function &F : M) {
     // Function may not have a name: like using asm("") to overwrite the name.
     // Ignore in this case.
     if (!F.hasName())
       continue;
     const std::string &PGOFuncName = getPGOFuncName(F, InLTO);
-    addFuncName(PGOFuncName);
+    if (Error E = addFuncName(PGOFuncName))
+      return E;
     MD5FuncMap.emplace_back(Function::getGUID(PGOFuncName), &F);
     // In ThinLTO, local function may have been promoted to global and have
     // suffix added to the function name. We need to add the stripped function
@@ -346,13 +347,15 @@ void InstrProfSymtab::create(Module &M, bool InLTO) {
       auto pos = PGOFuncName.find('.');
       if (pos != std::string::npos) {
         const std::string &OtherFuncName = PGOFuncName.substr(0, pos);
-        addFuncName(OtherFuncName);
+        if (Error E = addFuncName(OtherFuncName))
+          return E;
         MD5FuncMap.emplace_back(Function::getGUID(OtherFuncName), &F);
       }
     }
   }
 
   finalizeSymtab();
+  return Error::success();
 }
 
 Error collectPGOFuncNameStrings(ArrayRef<std::string> NameStrs,
@@ -447,7 +450,8 @@ Error readPGOFuncNameStrings(StringRef NameStrings, InstrProfSymtab &Symtab) {
     SmallVector<StringRef, 0> Names;
     NameStrings.split(Names, getInstrProfNameSeparator());
     for (StringRef &Name : Names)
-      Symtab.addFuncName(Name);
+      if (Error E = Symtab.addFuncName(Name))
+        return E;
 
     while (P < EndP && *P == 0)
       P++;