Revert "Re-commit r192758 - MC: quote tricky symbol names in asm output"

This caused the clang-native-mingw32-win7 buildbot to break.

The assembler was complaining about the following lines that were showing up
in the asm for CrashRecoveryContext.cpp:

  movl  $"__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4", 4(%eax)
  calll "_AddVectoredExceptionHandler@8"
  .def   "__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4";
  "__ZL16ExceptionHandlerP19_EXCEPTION_POINTERS@4":
  calll "_RemoveVectoredExceptionHandler@4"

Reverting for now.

llvm-svn: 192940

5 files changed, 20 insertions, 40 deletions

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 75f5c78b70b..9a362563a7e 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -792,25 +792,19 @@ bool AsmParser::parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
     EndLoc = SMLoc::getFromPointer(Identifier.end());
 
     // This is a symbol reference.
-    StringRef SymbolName = Identifier;
-    MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
     std::pair<StringRef, StringRef> Split = Identifier.split('@');
+    MCSymbol *Sym = getContext().GetOrCreateSymbol(Split.first);
 
-    if (Split.first.size() != Identifier.size() &&
-        FirstTokenKind != AsmToken::String) {
-      SymbolName = Split.first;
-      StringRef VariantName = Split.second;
-
-      // Lookup the symbol variant.
-      Variant = MCSymbolRefExpr::getVariantKindForName(VariantName);
+    // Lookup the symbol variant if used.
+    MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+    if (Split.first.size() != Identifier.size()) {
+      Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
       if (Variant == MCSymbolRefExpr::VK_Invalid) {
         Variant = MCSymbolRefExpr::VK_None;
-        return TokError("invalid variant '" + VariantName + "'");
+        return TokError("invalid variant '" + Split.second + "'");
       }
     }
 
-    MCSymbol *Sym = getContext().GetOrCreateSymbol(SymbolName);
-
     // If this is an absolute variable reference, substitute it now to preserve
     // semantics in the face of reassignment.
     if (Sym->isVariable() && isa<MCConstantExpr>(Sym->getVariableValue())) {
diff --git a/llvm/lib/MC/MCParser/COFFAsmParser.cpp b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
index b3c094366ab..df1794c9799 100644
--- a/llvm/lib/MC/MCParser/COFFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
@@ -295,7 +295,12 @@ bool COFFAsmParser::ParseSectionSwitch(StringRef Section,
 }
 
 bool COFFAsmParser::ParseSectionName(StringRef &SectionName) {
-  return getParser().parseIdentifier(SectionName);
+  if (!getLexer().is(AsmToken::Identifier))
+    return true;
+
+  SectionName = getTok().getIdentifier();
+  Lex();
+  return false;
 }
 
 // .section name [, "flags"]
diff --git a/llvm/lib/MC/MCSectionCOFF.cpp b/llvm/lib/MC/MCSectionCOFF.cpp
index a8f5db095b1..64aa2c5c49e 100644
--- a/llvm/lib/MC/MCSectionCOFF.cpp
+++ b/llvm/lib/MC/MCSectionCOFF.cpp
@@ -39,22 +39,6 @@ void MCSectionCOFF::setSelection(int Selection,
   Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
 }
 
-static bool isAcceptableSectionNameChar(char C) {
-  return (C >= 'a' && C <= 'z') ||
-         (C >= 'A' && C <= 'Z') ||
-         (C >= '0' && C <= '9') ||
-         C == '_' || C == '$' || C == '.';
-}
-
-/// NameNeedsQuoting - Return true if the identifier \p Str needs quotes to be
-/// syntactically correct.
-static bool sectionNameNeedsQuoting(StringRef Name) {
-  for (unsigned i = 0, e = Name.size(); i != e; ++i)
-    if (!isAcceptableSectionNameChar(Name[i]))
-      return true;
-  return false;
-}
-
 void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
                                          raw_ostream &OS,
                                          const MCExpr *Subsection) const {
@@ -65,10 +49,7 @@ void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
     return;
   }
 
-  if (sectionNameNeedsQuoting(getSectionName()))
-    OS << "\t.section\t" << '"' << getSectionName() << '"' << ",\"";
-  else
-    OS << "\t.section\t" << getSectionName() << ",\"";
+  OS << "\t.section\t" << getSectionName() << ",\"";
   if (getKind().isText())
     OS << 'x';
   if (getKind().isWriteable())
diff --git a/llvm/lib/MC/MCSymbol.cpp b/llvm/lib/MC/MCSymbol.cpp
index f386c3bc90a..b973c57f7b8 100644
--- a/llvm/lib/MC/MCSymbol.cpp
+++ b/llvm/lib/MC/MCSymbol.cpp
@@ -18,10 +18,12 @@ const MCSection *MCSymbol::AbsolutePseudoSection =
   reinterpret_cast<const MCSection *>(1);
 
 static bool isAcceptableChar(char C) {
-  return (C >= 'a' && C <= 'z') ||
-         (C >= 'A' && C <= 'Z') ||
-         (C >= '0' && C <= '9') ||
-         C == '_' || C == '$' || C == '.';
+  if ((C < 'a' || C > 'z') &&
+      (C < 'A' || C > 'Z') &&
+      (C < '0' || C > '9') &&
+      C != '_' && C != '$' && C != '.' && C != '@')
+    return false;
+  return true;
 }
 
 /// NameNeedsQuoting - Return true if the identifier \p Str needs quotes to be
diff --git a/llvm/lib/Target/X86/X86AsmPrinter.cpp b/llvm/lib/Target/X86/X86AsmPrinter.cpp
index d7f7c3e55da..7d7a1add221 100644
--- a/llvm/lib/Target/X86/X86AsmPrinter.cpp
+++ b/llvm/lib/Target/X86/X86AsmPrinter.cpp
@@ -519,11 +519,9 @@ void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
   if (Subtarget->isTargetEnvMacho())
     OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
 
-  if (Subtarget->isTargetCOFF() && Subtarget->isTargetWindows()) {
+  if (Subtarget->isTargetCOFF()) {
     // Emit an absolute @feat.00 symbol.  This appears to be some kind of
     // compiler features bitfield read by link.exe.
-    // We only do this on win32, since on cygwin etc. we use the GNU assembler,
-    // which doesn't handle this symbol.
     if (!Subtarget->is64Bit()) {
       MCSymbol *S = MMI->getContext().GetOrCreateSymbol(StringRef("@feat.00"));
       OutStreamer.BeginCOFFSymbolDef(S);