Revert r240302 ("Bring r240130 back.").

This causes errors like:

  ld: error: blah.o: requires dynamic R_X86_64_PC32 reloc against '' which
  may overflow at runtime; recompile with -fPIC
  blah.cc:function f(): error: undefined reference to ''
  blah.o:g(): error: undefined reference to ''

I have not yet come up with an appropriate reproduction.

llvm-svn: 240394

1 files changed, 15 insertions, 13 deletions

diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
index 01074eb..c601c56 100644
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -116,7 +116,7 @@ MCSymbol *MCContext::getOrCreateSymbol(const Twine &Name) {
 
   MCSymbol *&Sym = Symbols[NameRef];
   if (!Sym)
-    Sym = createSymbol(NameRef, false);
+    Sym = createSymbol(NameRef, false, false);
 
   return Sym;
 }
@@ -175,16 +175,17 @@ MCSymbol *MCContext::createSymbolImpl(const StringMapEntry<bool> *Name,
                                     IsTemporary);
 }
 
-MCSymbol *MCContext::createSymbol(StringRef Name, bool AlwaysAddSuffix) {
+MCSymbol *MCContext::createSymbol(StringRef Name, bool AlwaysAddSuffix,
+                                  bool CanBeUnnamed) {
+  if (CanBeUnnamed && !UseNamesOnTempLabels)
+    return createSymbolImpl(nullptr, true);
+
   // Determine whether this is an user writter assembler temporary or normal
   // label, if used.
-  bool IsTemporary = false;
-  if (AllowTemporaryLabels)
+  bool IsTemporary = CanBeUnnamed;
+  if (AllowTemporaryLabels && !IsTemporary)
     IsTemporary = Name.startswith(MAI->getPrivateGlobalPrefix());
 
-  if (IsTemporary && !UseNamesOnTempLabels)
-    return createSymbolImpl(nullptr, true);
-
   SmallString<128> NewName = Name;
   bool AddSuffix = AlwaysAddSuffix;
   unsigned &NextUniqueID = NextID[Name];
@@ -205,20 +206,21 @@ MCSymbol *MCContext::createSymbol(StringRef Name, bool AlwaysAddSuffix) {
   llvm_unreachable("Infinite loop");
 }
 
-MCSymbol *MCContext::createTempSymbol(const Twine &Name, bool AlwaysAddSuffix) {
+MCSymbol *MCContext::createTempSymbol(const Twine &Name, bool AlwaysAddSuffix,
+                                      bool CanBeUnnamed) {
   SmallString<128> NameSV;
   raw_svector_ostream(NameSV) << MAI->getPrivateGlobalPrefix() << Name;
-  return createSymbol(NameSV, AlwaysAddSuffix);
+  return createSymbol(NameSV, AlwaysAddSuffix, CanBeUnnamed);
 }
 
 MCSymbol *MCContext::createLinkerPrivateTempSymbol() {
   SmallString<128> NameSV;
   raw_svector_ostream(NameSV) << MAI->getLinkerPrivateGlobalPrefix() << "tmp";
-  return createSymbol(NameSV, true);
+  return createSymbol(NameSV, true, false);
 }
 
-MCSymbol *MCContext::createTempSymbol() {
-  return createTempSymbol("tmp", true);
+MCSymbol *MCContext::createTempSymbol(bool CanBeUnnamed) {
+  return createTempSymbol("tmp", true, CanBeUnnamed);
 }
 
 unsigned MCContext::NextInstance(unsigned LocalLabelVal) {
@@ -239,7 +241,7 @@ MCSymbol *MCContext::getOrCreateDirectionalLocalSymbol(unsigned LocalLabelVal,
                                                        unsigned Instance) {
   MCSymbol *&Sym = LocalSymbols[std::make_pair(LocalLabelVal, Instance)];
   if (!Sym)
-    Sym = createTempSymbol();
+    Sym = createTempSymbol(false);
   return Sym;
 }