Propagating prior merge from 'llvm.org/master'.

Author: Automerger

include/clang/Basic/LangOptions.def

@@ -133,7 +133,7 @@ LANGOPT(Freestanding, 1, 0, "freestanding implementation")
 LANGOPT(NoBuiltin         , 1, 0, "disable builtin functions")
 LANGOPT(NoMathBuiltin     , 1, 0, "disable math builtin functions")
 LANGOPT(GNUAsm            , 1, 1, "GNU-style inline assembly")
-LANGOPT(Coroutines        , 1, 0, "C++ coroutines")
+LANGOPT(CoroutinesTS      , 1, 0, "C++ coroutines TS")
 
 BENIGN_LANGOPT(ThreadsafeStatics , 1, 1, "thread-safe static initializers")
 LANGOPT(POSIXThreads      , 1, 0, "POSIX thread support")

include/clang/Basic/SourceManager.h

@@ -1291,7 +1291,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///
   /// Note that this name does not respect \#line directives.  Use
   /// getPresumedLoc for normal clients.
-  const char *getBufferName(SourceLocation Loc, bool *Invalid = nullptr) const;
+  StringRef getBufferName(SourceLocation Loc, bool *Invalid = nullptr) const;
 
   /// \brief Return the file characteristic of the specified source
   /// location, indicating whether this is a normal file, a system

include/clang/Driver/CC1Options.td

@@ -638,10 +638,6 @@ def fdefault_calling_conv_EQ : Joined<["-"], "fdefault-calling-conv=">,
 def finclude_default_header : Flag<["-"], "finclude-default-header">,
   HelpText<"Include the default header file for OpenCL">;
 
-// C++ TSes.
-def fcoroutines : Flag<["-"], "fcoroutines">,
-  HelpText<"Enable support for the C++ Coroutines TS">;
-
 //===----------------------------------------------------------------------===//
 // Header Search Options
 //===----------------------------------------------------------------------===//

include/clang/Driver/Options.td

@@ -481,6 +481,13 @@ def fno_autolink : Flag <["-"], "fno-autolink">, Group<f_Group>,
   Flags<[DriverOption, CC1Option]>,
   HelpText<"Disable generation of linker directives for automatic library linking">;
 
+// C++ Coroutines TS
+def fcoroutines_ts : Flag <["-"], "fcoroutines-ts">, Group<f_Group>,
+  Flags<[DriverOption, CC1Option]>,
+  HelpText<"Enable support for the C++ Coroutines TS">;
+def fno_coroutines_ts : Flag <["-"], "fno-coroutines-ts">, Group<f_Group>,
+  Flags<[DriverOption]>;
+
 def fembed_bitcode_EQ : Joined<["-"], "fembed-bitcode=">,
     Group<f_Group>, Flags<[DriverOption, CC1Option]>, MetaVarName<"<option>">,
     HelpText<"Embed LLVM bitcode (option: off, all, bitcode, marker)">;

include/clang/Lex/DirectoryLookup.h

@@ -88,7 +88,7 @@ class DirectoryLookup {
 
   /// getName - Return the directory or filename corresponding to this lookup
   /// object.
-  const char *getName() const;
+  StringRef getName() const;
 
   /// getDir - Return the directory that this entry refers to.
   ///

include/clang/Lex/HeaderMap.h

@@ -45,7 +45,7 @@ class HeaderMapImpl {
                            SmallVectorImpl<char> &DestPath) const;
 
   /// Return the filename of the headermap.
-  const char *getFileName() const;
+  StringRef getFileName() const;
 
   /// Print the contents of this headermap to stderr.
   void dump() const;

include/clang/Rewrite/Core/HTMLRewrite.h

@@ -62,8 +62,8 @@ namespace html {
 
   void AddLineNumbers(Rewriter& R, FileID FID);
 
-  void AddHeaderFooterInternalBuiltinCSS(Rewriter& R, FileID FID,
-                                         const char *title = nullptr);
+  void AddHeaderFooterInternalBuiltinCSS(Rewriter &R, FileID FID,
+                                         StringRef title);
 
   /// SyntaxHighlight - Relex the specified FileID and annotate the HTML with
   /// information about keywords, comments, etc.

lib/Basic/IdentifierTable.cpp

@@ -150,7 +150,7 @@ static KeywordStatus getKeywordStatus(const LangOptions &LangOpts,
   if (LangOpts.ObjC2 && (Flags & KEYARC)) return KS_Enabled;
   if (LangOpts.ObjC2 && (Flags & KEYOBJC2)) return KS_Enabled;
   if (LangOpts.ConceptsTS && (Flags & KEYCONCEPTS)) return KS_Enabled;
-  if (LangOpts.Coroutines && (Flags & KEYCOROUTINES)) return KS_Enabled;
+  if (LangOpts.CoroutinesTS && (Flags & KEYCOROUTINES)) return KS_Enabled;
   if (LangOpts.ModulesTS && (Flags & KEYMODULES)) return KS_Enabled;
   if (LangOpts.CPlusPlus && (Flags & KEYCXX11)) return KS_Future;
   return KS_Disabled;

lib/Basic/SourceManager.cpp

@@ -1437,8 +1437,8 @@ SourceManager::getFileCharacteristic(SourceLocation Loc) const {
 /// Return the filename or buffer identifier of the buffer the location is in.
 /// Note that this name does not respect \#line directives.  Use getPresumedLoc
 /// for normal clients.
-const char *SourceManager::getBufferName(SourceLocation Loc, 
-                                         bool *Invalid) const {
+StringRef SourceManager::getBufferName(SourceLocation Loc,
+                                       bool *Invalid) const {
   if (isInvalid(Loc, Invalid)) return "<invalid loc>";
 
   return getBuffer(getFileID(Loc), Invalid)->getBufferIdentifier();
@@ -1470,7 +1470,7 @@ PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc,
   // To get the source name, first consult the FileEntry (if one exists)
   // before the MemBuffer as this will avoid unnecessarily paging in the
   // MemBuffer.
-  const char *Filename;
+  StringRef Filename;
   if (C->OrigEntry)
     Filename = C->OrigEntry->getName();
   else
@@ -1513,7 +1513,7 @@ PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc,
     }
   }
 
-  return PresumedLoc(Filename, LineNo, ColNo, IncludeLoc);
+  return PresumedLoc(Filename.data(), LineNo, ColNo, IncludeLoc);
 }
 
 /// \brief Returns whether the PresumedLoc for a given SourceLocation is
@@ -2095,10 +2095,10 @@ bool SourceManager::isBeforeInTranslationUnit(SourceLocation LHS,
 
   // Clear the lookup cache, it depends on a common location.
   IsBeforeInTUCache.clear();
-  const char *LB = getBuffer(LOffs.first)->getBufferIdentifier();
-  const char *RB = getBuffer(ROffs.first)->getBufferIdentifier();
-  bool LIsBuiltins = strcmp("<built-in>", LB) == 0;
-  bool RIsBuiltins = strcmp("<built-in>", RB) == 0;
+  StringRef LB = getBuffer(LOffs.first)->getBufferIdentifier();
+  StringRef RB = getBuffer(ROffs.first)->getBufferIdentifier();
+  bool LIsBuiltins = LB == "<built-in>";
+  bool RIsBuiltins = RB == "<built-in>";
   // Sort built-in before non-built-in.
   if (LIsBuiltins || RIsBuiltins) {
     if (LIsBuiltins != RIsBuiltins)
@@ -2107,17 +2107,17 @@ bool SourceManager::isBeforeInTranslationUnit(SourceLocation LHS,
     // lower IDs come first.
     return LOffs.first < ROffs.first;
   }
-  bool LIsAsm = strcmp("<inline asm>", LB) == 0;
-  bool RIsAsm = strcmp("<inline asm>", RB) == 0;
+  bool LIsAsm = LB == "<inline asm>";
+  bool RIsAsm = RB == "<inline asm>";
   // Sort assembler after built-ins, but before the rest.
   if (LIsAsm || RIsAsm) {
     if (LIsAsm != RIsAsm)
       return RIsAsm;
     assert(LOffs.first == ROffs.first);
     return false;
   }
-  bool LIsScratch = strcmp("<scratch space>", LB) == 0;
-  bool RIsScratch = strcmp("<scratch space>", RB) == 0;
+  bool LIsScratch = LB == "<scratch space>";
+  bool RIsScratch = RB == "<scratch space>";
   // Sort scratch after inline asm, but before the rest.
   if (LIsScratch || RIsScratch) {
     if (LIsScratch != RIsScratch)

lib/CodeGen/CGCXX.cpp

@@ -134,6 +134,11 @@ bool CodeGenModule::TryEmitDefinitionAsAlias(GlobalDecl AliasDecl,
   llvm::GlobalValue::LinkageTypes TargetLinkage =
       getFunctionLinkage(TargetDecl);
 
+  // available_externally definitions aren't real definitions, so we cannot
+  // create an alias to one.
+  if (TargetLinkage == llvm::GlobalValue::AvailableExternallyLinkage)
+    return true;
+
   // Check if we have it already.
   StringRef MangledName = getMangledName(AliasDecl);
   llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
@@ -156,14 +161,7 @@ bool CodeGenModule::TryEmitDefinitionAsAlias(GlobalDecl AliasDecl,
 
   // Instead of creating as alias to a linkonce_odr, replace all of the uses
   // of the aliasee.
-  if (llvm::GlobalValue::isDiscardableIfUnused(Linkage) &&
-     (TargetLinkage != llvm::GlobalValue::AvailableExternallyLinkage ||
-      !TargetDecl.getDecl()->hasAttr<AlwaysInlineAttr>())) {
-    // FIXME: An extern template instantiation will create functions with
-    // linkage "AvailableExternally". In libc++, some classes also define
-    // members with attribute "AlwaysInline" and expect no reference to
-    // be generated. It is desirable to reenable this optimisation after
-    // corresponding LLVM changes.
+  if (llvm::GlobalValue::isDiscardableIfUnused(Linkage)) {
     addReplacement(MangledName, Aliasee);
     return false;
   }