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

The reason this got reverted was that the @feat.00 symbol which was emitted
for every TU became quoted, and on cygwin/mingw we use the gas assembler which
couldn't handle the quotes.

This commit fixes the problem by only emitting @feat.00 for win32, where we use
clang -cc1as to assemble. gas would just drop this symbol anyway, so there is no
loss there.

With @feat.00 gone, there shouldn't be quoted symbols showing up on cygwin since
it uses the Itanium ABI, which doesn't put these funny characters in symbols.

> Because of win32 mangling, we produce symbol and section names with
> funny characters in them, most notably @ characters.
>
> MC would choke on trying to parse its own assembly output. This patch addresses
> that by:
>
> - Making @ trigger quoting of symbol names
> - Also quote section names in the same way
> - Just parse section names like other identifiers (to allow for quotes)
> - Don't assume @ signifies a symbol variant if it is in a string.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192859 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 9a362563a7ea93c855f9a22293756a979f642cd6..75f5c78b70bbe63f420b6a976a573e43f037880f 100644 (file)
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -792,19 +792,25 @@ bool AsmParser::parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
     EndLoc = SMLoc::getFromPointer(Identifier.end());
 
     // This is a symbol reference.
     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('@');
     std::pair<StringRef, StringRef> Split = Identifier.split('@');

-    MCSymbol *Sym = getContext().GetOrCreateSymbol(Split.first);

 
 

-    // Lookup the symbol variant if used.
-    MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
-    if (Split.first.size() != Identifier.size()) {
-      Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
+    if (Split.first.size() != Identifier.size() &&
+        FirstTokenKind != AsmToken::String) {
+      SymbolName = Split.first;
+      StringRef VariantName = Split.second;
+
+      // Lookup the symbol variant.
+      Variant = MCSymbolRefExpr::getVariantKindForName(VariantName);

       if (Variant == MCSymbolRefExpr::VK_Invalid) {
         Variant = MCSymbolRefExpr::VK_None;
       if (Variant == MCSymbolRefExpr::VK_Invalid) {
         Variant = MCSymbolRefExpr::VK_None;

-        return TokError("invalid variant '" + Split.second + "'");
+        return TokError("invalid variant '" + VariantName + "'");

       }
     }
 
       }
     }
 

+    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())) {
     // 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/lib/MC/MCParser/COFFAsmParser.cpp b/lib/MC/MCParser/COFFAsmParser.cpp
index df1794c979920aa85e8218faca4f11d14c2b10a3..b3c094366ab931d3281fabca57dc9ed032f4f2a4 100644 (file)
--- a/lib/MC/MCParser/COFFAsmParser.cpp
+++ b/lib/MC/MCParser/COFFAsmParser.cpp
@@ -295,12 +295,7 @@ bool COFFAsmParser::ParseSectionSwitch(StringRef Section,
 }
 
 bool COFFAsmParser::ParseSectionName(StringRef &SectionName) {
 }
 
 bool COFFAsmParser::ParseSectionName(StringRef &SectionName) {

-  if (!getLexer().is(AsmToken::Identifier))
-    return true;
-
-  SectionName = getTok().getIdentifier();
-  Lex();
-  return false;
+  return getParser().parseIdentifier(SectionName);

 }
 
 // .section name [, "flags"]
 }
 
 // .section name [, "flags"]

diff --git a/lib/MC/MCSectionCOFF.cpp b/lib/MC/MCSectionCOFF.cpp
index 64aa2c5c49ea9d3bc9549b6fbd4ef864850bb477..a8f5db095b187af7f06018c7cb54f85fa2644d33 100644 (file)
--- a/lib/MC/MCSectionCOFF.cpp
+++ b/lib/MC/MCSectionCOFF.cpp
@@ -39,6 +39,22 @@ void MCSectionCOFF::setSelection(int Selection,
   Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
 }
 
   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 {
 void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
                                          raw_ostream &OS,
                                          const MCExpr *Subsection) const {


@@ -49,7 +65,10 @@ void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
     return;
   }
 
     return;
   }
 

-  OS << "\t.section\t" << getSectionName() << ",\"";
+  if (sectionNameNeedsQuoting(getSectionName()))
+    OS << "\t.section\t" << '"' << getSectionName() << '"' << ",\"";
+  else
+    OS << "\t.section\t" << getSectionName() << ",\"";

   if (getKind().isText())
     OS << 'x';
   if (getKind().isWriteable())
   if (getKind().isText())
     OS << 'x';
   if (getKind().isWriteable())

diff --git a/lib/MC/MCSymbol.cpp b/lib/MC/MCSymbol.cpp
index b973c57f7b811fe155b750b0c7175020007262c1..f386c3bc90aca85fc65e8cf1ae96cee334dfcfd7 100644 (file)
--- a/lib/MC/MCSymbol.cpp
+++ b/lib/MC/MCSymbol.cpp
@@ -18,12 +18,10 @@ const MCSection *MCSymbol::AbsolutePseudoSection =
   reinterpret_cast<const MCSection *>(1);
 
 static bool isAcceptableChar(char C) {
   reinterpret_cast<const MCSection *>(1);
 
 static bool isAcceptableChar(char C) {

-  if ((C < 'a' || C > 'z') &&
-      (C < 'A' || C > 'Z') &&
-      (C < '0' || C > '9') &&
-      C != '_' && C != '$' && C != '.' && C != '@')
-    return false;
-  return true;
+  return (C >= 'a' && C <= 'z') ||
+         (C >= 'A' && C <= 'Z') ||
+         (C >= '0' && C <= '9') ||
+         C == '_' || C == '$' || C == '.';

 }
 
 /// NameNeedsQuoting - Return true if the identifier \p Str needs quotes to be
 }
 
 /// NameNeedsQuoting - Return true if the identifier \p Str needs quotes to be

diff --git a/lib/Target/X86/X86AsmPrinter.cpp b/lib/Target/X86/X86AsmPrinter.cpp
index 7d7a1add2219a1ce69846b52991241ae0062eb44..d7f7c3e55daa919e02eb0391d18aae7f41eccbf4 100644 (file)
--- a/lib/Target/X86/X86AsmPrinter.cpp
+++ b/lib/Target/X86/X86AsmPrinter.cpp
@@ -519,9 +519,11 @@ void X86AsmPrinter::EmitStartOfAsmFile(Module &M) {
   if (Subtarget->isTargetEnvMacho())
     OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
 
   if (Subtarget->isTargetEnvMacho())
     OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
 

-  if (Subtarget->isTargetCOFF()) {
+  if (Subtarget->isTargetCOFF() && Subtarget->isTargetWindows()) {

     // Emit an absolute @feat.00 symbol.  This appears to be some kind of
     // compiler features bitfield read by link.exe.
     // 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);
     if (!Subtarget->is64Bit()) {
       MCSymbol *S = MMI->getContext().GetOrCreateSymbol(StringRef("@feat.00"));
       OutStreamer.BeginCOFFSymbolDef(S);

diff --git a/test/CodeGen/X86/coff-feat00.ll b/test/CodeGen/X86/coff-feat00.ll
index 1dcd4276399a962398cecfe35de38743db197bf2..048aa34345d588be54831b585138eeef82755b2c 100644 (file)
--- a/test/CodeGen/X86/coff-feat00.ll
+++ b/test/CodeGen/X86/coff-feat00.ll
@@ -1,7 +1,9 @@
-; RUN: llc -O0 -mtriple=i386-pc-win32 -filetype=asm -o - %s | FileCheck %s
+; RUN: llc -O0 -mtriple=i386-pc-win32 -filetype=asm -o - %s | FileCheck %s --check-prefix=WIN32
+; RUN: llc -O0 -mtriple=i386-pc-cygwin -filetype=asm -o - %s | FileCheck %s --check-prefix=CYGWIN

 
 define i32 @foo() {
   ret i32 0
 }
 
 
 define i32 @foo() {
   ret i32 0
 }
 

-; CHECK: @feat.00 = 1
+; WIN32: "@feat.00" = 1
+; CYGWIN-NOT: "@feat.00" = 1

diff --git a/test/CodeGen/X86/fastcall-correct-mangling.ll b/test/CodeGen/X86/fastcall-correct-mangling.ll
index 3569d36541f7a48b2dfcf2728fa9a4dc778269d7..17addbc3e16405bcc626f8e855864afbbd2c8eb9 100644 (file)
--- a/test/CodeGen/X86/fastcall-correct-mangling.ll
+++ b/test/CodeGen/X86/fastcall-correct-mangling.ll
@@ -3,7 +3,7 @@
 ; Check that a fastcall function gets correct mangling
 
 define x86_fastcallcc void @func(i64 %X, i8 %Y, i8 %G, i16 %Z) {
 ; Check that a fastcall function gets correct mangling
 
 define x86_fastcallcc void @func(i64 %X, i8 %Y, i8 %G, i16 %Z) {

-; CHECK: @func@20:
+; CHECK: "@func@20":

         ret void
 }
 
         ret void
 }
 

diff --git a/test/CodeGen/X86/stdcall.ll b/test/CodeGen/X86/stdcall.ll
index 73826ed0b29dc794920daa6b88d991dcf1c008bd..34f90c5ee38ba0e26ba1eb6f20c751f7f8b83b5b 100644 (file)
--- a/test/CodeGen/X86/stdcall.ll
+++ b/test/CodeGen/X86/stdcall.ll
@@ -5,7 +5,7 @@
 
 define internal x86_stdcallcc void @MyFunc() nounwind {
 entry:
 
 define internal x86_stdcallcc void @MyFunc() nounwind {
 entry:

-; CHECK: MyFunc@0:
+; CHECK: "_MyFunc@0":

 ; CHECK: ret
   ret void
 }
 ; CHECK: ret
   ret void
 }


@@ -20,5 +20,5 @@ entry:
 
 @B = global %0 { void (...)* bitcast (void ()* @MyFunc to void (...)*) }, align 4
 ; CHECK: _B:
 
 @B = global %0 { void (...)* bitcast (void ()* @MyFunc to void (...)*) }, align 4
 ; CHECK: _B:

-; CHECK: .long _MyFunc@0
+; CHECK: .long "_MyFunc@0"

 
 

diff --git a/test/MC/COFF/quoted-names.ll b/test/MC/COFF/quoted-names.ll
new file mode 100644 (file)
index 0000000..920035f
--- /dev/null
+++ b/test/MC/COFF/quoted-names.ll
@@ -0,0 +1,20 @@
+; Check that certain symbol and section names are quoted in the asm output.
+; RUN: llc -mtriple=i686-pc-win32 %s -o - | FileCheck %s
+
+; Check that the symbol and section names can round-trip through the assembler.
+; RUN: llc -mtriple=i686-pc-win32 %s -o - | llvm-mc -triple i686-pc-win32 -filetype=obj | llvm-readobj -s -section-symbols | FileCheck %s --check-prefix=READOBJ
+
+@"\01??__E_Generic_object@?$_Error_objects@H@std@@YAXXZ" = global i32 0
+
+define weak i32 @"\01??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51"() section ".text" {
+  %res = load i32* @"\01??__E_Generic_object@?$_Error_objects@H@std@@YAXXZ"
+  ret i32 %res
+}
+
+; CHECK: .section ".text$??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51","xr"
+; CHECK: .globl "??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51"
+; CHECK: "??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51"
+
+; READOBJ: Symbol
+; READOBJ: Name: ??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51
+; READOBJ: Section: .text$??_B?$num_put@_WV?$back_insert_iterator@V?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@std@@@std@@51