Update llvm/clang to trunk r126547.

There are several bugfixes in this update, but the most important one is
to ensure __start_ and __stop_ symbols for linker sets and kernel module
metadata are always emitted in object files:

  http://llvm.org/bugs/show_bug.cgi?id=9292

Before this fix, if you compiled kernel modules with clang, they would
not be properly processed by kldxref, and if they had any dependencies,
the kernel would fail to load those.  Another problem occurred when
attempting to mount a tmpfs filesystem, which would result in 'operation
not supported by device'.

11 files changed, 72 insertions, 20 deletions

diff --git a/contrib/llvm/lib/MC/ELFObjectWriter.cpp b/contrib/llvm/lib/MC/ELFObjectWriter.cpp
index 8a00a16..ea1629d 100644
--- a/contrib/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/contrib/llvm/lib/MC/ELFObjectWriter.cpp
@@ -833,7 +833,11 @@ static bool isInSymtab(const MCAssembler &Asm, const MCSymbolData &Data,
     return true;
 
   const MCSymbol &A = Symbol.AliasedSymbol();
-  if (!A.isVariable() && A.isUndefined() && !Data.isCommon())
+  if (Symbol.isVariable() && !A.isVariable() && A.isUndefined())
+    return false;
+
+  bool IsGlobal = GetBinding(Data) == ELF::STB_GLOBAL;
+  if (!Symbol.isVariable() && Symbol.isUndefined() && !IsGlobal)
     return false;
 
   if (!Asm.isSymbolLinkerVisible(Symbol) && !Symbol.isUndefined())
@@ -1732,6 +1736,10 @@ unsigned X86ELFObjectWriter::GetRelocType(const MCValue &Target,
         assert(Modifier == MCSymbolRefExpr::VK_None);
         Type = ELF::R_X86_64_PC16;
         break;
+      case FK_PCRel_1:
+        assert(Modifier == MCSymbolRefExpr::VK_None);
+        Type = ELF::R_X86_64_PC8;
+        break;
       }
     } else {
       switch ((unsigned)Fixup.getKind()) {
diff --git a/contrib/llvm/lib/MC/MCAsmInfo.cpp b/contrib/llvm/lib/MC/MCAsmInfo.cpp
index cc1afbd..8199fb2 100644
--- a/contrib/llvm/lib/MC/MCAsmInfo.cpp
+++ b/contrib/llvm/lib/MC/MCAsmInfo.cpp
@@ -65,6 +65,7 @@ MCAsmInfo::MCAsmInfo() {
   WeakDefDirective = 0;
   LinkOnceDirective = 0;
   HiddenVisibilityAttr = MCSA_Hidden;
+  HiddenDeclarationVisibilityAttr = MCSA_Hidden;
   ProtectedVisibilityAttr = MCSA_Protected;
   HasLEB128 = false;
   SupportsDebugInformation = false;
diff --git a/contrib/llvm/lib/MC/MCAsmInfoDarwin.cpp b/contrib/llvm/lib/MC/MCAsmInfoDarwin.cpp
index 13776f0..526ad0d 100644
--- a/contrib/llvm/lib/MC/MCAsmInfoDarwin.cpp
+++ b/contrib/llvm/lib/MC/MCAsmInfoDarwin.cpp
@@ -45,6 +45,7 @@ MCAsmInfoDarwin::MCAsmInfoDarwin() {
   HasAggressiveSymbolFolding = false;
 
   HiddenVisibilityAttr = MCSA_PrivateExtern;
+  HiddenDeclarationVisibilityAttr = MCSA_Invalid;
   // Doesn't support protected visibility.
   ProtectedVisibilityAttr = MCSA_Global;
   
diff --git a/contrib/llvm/lib/MC/MCDisassembler/EDOperand.cpp b/contrib/llvm/lib/MC/MCDisassembler/EDOperand.cpp
index cfeb56f..2b0c73e 100644
--- a/contrib/llvm/lib/MC/MCDisassembler/EDOperand.cpp
+++ b/contrib/llvm/lib/MC/MCDisassembler/EDOperand.cpp
@@ -152,10 +152,23 @@ int EDOperand::evaluate(uint64_t &result,
       uint64_t scaleAmount = Inst.Inst->getOperand(MCOpIndex+1).getImm();
       unsigned indexReg = Inst.Inst->getOperand(MCOpIndex+2).getReg();
       int64_t displacement = Inst.Inst->getOperand(MCOpIndex+3).getImm();
-      //unsigned segmentReg = Inst.Inst->getOperand(MCOpIndex+4).getReg();
-      
+    
       uint64_t addr = 0;
         
+      unsigned segmentReg = Inst.Inst->getOperand(MCOpIndex+4).getReg();
+        
+      if (segmentReg != 0 && Disassembler.Key.Arch == Triple::x86_64) {
+        unsigned fsID = Disassembler.registerIDWithName("FS");
+        unsigned gsID = Disassembler.registerIDWithName("GS");
+        
+        if (segmentReg == fsID ||
+            segmentReg == gsID) {
+          uint64_t segmentBase;
+          if (!callback(&segmentBase, segmentReg, arg))
+            addr += segmentBase;        
+        }
+      }
+        
       if (baseReg) {
         uint64_t baseVal;
         if (callback(&baseVal, baseReg, arg))
@@ -175,7 +188,7 @@ int EDOperand::evaluate(uint64_t &result,
       result = addr;
       return 0;
     }
-    }
+    } // switch (operandType)
     break;
   case Triple::arm:
   case Triple::thumb:
@@ -203,6 +216,7 @@ int EDOperand::evaluate(uint64_t &result,
       return 0;
     }
     }
+    break;
   }
   
   return -1;
diff --git a/contrib/llvm/lib/MC/MCDisassembler/EDToken.cpp b/contrib/llvm/lib/MC/MCDisassembler/EDToken.cpp
index 400e164..de770b4 100644
--- a/contrib/llvm/lib/MC/MCDisassembler/EDToken.cpp
+++ b/contrib/llvm/lib/MC/MCDisassembler/EDToken.cpp
@@ -194,6 +194,10 @@ int EDToken::tokenize(std::vector<EDToken*> &tokens,
     tokens.push_back(token);
   }
   
+  // Free any parsed operands.
+  for (unsigned i = 0, e = parsedOperands.size(); i != e; ++i)
+    delete parsedOperands[i];
+
   return 0;
 }
 
diff --git a/contrib/llvm/lib/MC/MCObjectStreamer.cpp b/contrib/llvm/lib/MC/MCObjectStreamer.cpp
index 0358266..e67d9b0 100644
--- a/contrib/llvm/lib/MC/MCObjectStreamer.cpp
+++ b/contrib/llvm/lib/MC/MCObjectStreamer.cpp
@@ -242,7 +242,23 @@ void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
 
 void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
                                         unsigned char Value) {
-  new MCOrgFragment(*Offset, Value, getCurrentSectionData());
+  int64_t Res;
+  if (Offset->EvaluateAsAbsolute(Res, getAssembler())) {
+    new MCOrgFragment(*Offset, Value, getCurrentSectionData());
+    return;
+  }
+
+  MCSymbol *CurrentPos = getContext().CreateTempSymbol();
+  EmitLabel(CurrentPos);
+  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+  const MCExpr *Ref =
+    MCSymbolRefExpr::Create(CurrentPos, Variant, getContext());
+  const MCExpr *Delta =
+    MCBinaryExpr::Create(MCBinaryExpr::Sub, Offset, Ref, getContext());
+
+  if (!Delta->EvaluateAsAbsolute(Res, getAssembler()))
+    report_fatal_error("expected assembly-time absolute expression");
+  EmitFill(Res, Value, 0);
 }
 
 void MCObjectStreamer::Finish() {
diff --git a/contrib/llvm/lib/MC/MCParser/AsmParser.cpp b/contrib/llvm/lib/MC/MCParser/AsmParser.cpp
index c6d0da6..a84917f 100644
--- a/contrib/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/contrib/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -603,6 +603,8 @@ bool AsmParser::ParsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
     Lex(); // Eat the '('.
     return ParseParenExpr(Res, EndLoc);
   case AsmToken::LBrac:
+    if (!PlatformParser->HasBracketExpressions())
+      return TokError("brackets expression not supported on this target");
     Lex(); // Eat the '['.
     return ParseBracketExpr(Res, EndLoc);
   case AsmToken::Minus:
diff --git a/contrib/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/contrib/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index bfaf36a..dcf689a 100644
--- a/contrib/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/contrib/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -30,9 +30,12 @@ class ELFAsmParser : public MCAsmParserExtension {
 
   bool ParseSectionSwitch(StringRef Section, unsigned Type,
                           unsigned Flags, SectionKind Kind);
+  bool SeenIdent;
 
 public:
-  ELFAsmParser() {}
+  ELFAsmParser() : SeenIdent(false) {
+    BracketExpressionsSupported = true;
+  }
 
   virtual void Initialize(MCAsmParser &Parser) {
     // Call the base implementation.
@@ -456,13 +459,12 @@ bool ELFAsmParser::ParseDirectiveIdent(StringRef, SMLoc) {
                                SectionKind::getReadOnly(),
                                1, "");
 
-  static bool First = true;
-
   getStreamer().PushSection();
   getStreamer().SwitchSection(Comment);
-  if (First)
+  if (!SeenIdent) {
     getStreamer().EmitIntValue(0, 1);
-  First = false;
+    SeenIdent = true;
+  }
   getStreamer().EmitBytes(Data, 0);
   getStreamer().EmitIntValue(0, 1);
   getStreamer().PopSection();
diff --git a/contrib/llvm/lib/MC/MCParser/MCAsmParserExtension.cpp b/contrib/llvm/lib/MC/MCParser/MCAsmParserExtension.cpp
index c30d306..3f25a14 100644
--- a/contrib/llvm/lib/MC/MCParser/MCAsmParserExtension.cpp
+++ b/contrib/llvm/lib/MC/MCParser/MCAsmParserExtension.cpp
@@ -10,7 +10,8 @@
 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
 using namespace llvm;
 
-MCAsmParserExtension::MCAsmParserExtension() {
+MCAsmParserExtension::MCAsmParserExtension() :
+  BracketExpressionsSupported(false) {
 }
 
 MCAsmParserExtension::~MCAsmParserExtension() {
diff --git a/contrib/llvm/lib/MC/MCSectionMachO.cpp b/contrib/llvm/lib/MC/MCSectionMachO.cpp
index b897c0b..577e93a 100644
--- a/contrib/llvm/lib/MC/MCSectionMachO.cpp
+++ b/contrib/llvm/lib/MC/MCSectionMachO.cpp
@@ -101,16 +101,18 @@ void MCSectionMachO::PrintSwitchToSection(const MCAsmInfo &MAI,
     return;
   }
 
-  OS << ',';
-
   unsigned SectionType = TAA & MCSectionMachO::SECTION_TYPE;
   assert(SectionType <= MCSectionMachO::LAST_KNOWN_SECTION_TYPE &&
          "Invalid SectionType specified!");
 
-  if (SectionTypeDescriptors[SectionType].AssemblerName)
+  if (SectionTypeDescriptors[SectionType].AssemblerName) {
+    OS << ',';
     OS << SectionTypeDescriptors[SectionType].AssemblerName;
-  else
-    OS << "<<" << SectionTypeDescriptors[SectionType].EnumName << ">>";
+  } else {
+    // If we have no name for the attribute, stop here.
+    OS << '\n';
+    return;
+  }
 
   // If we don't have any attributes, we're done.
   unsigned SectionAttrs = TAA & MCSectionMachO::SECTION_ATTRIBUTES;
@@ -125,7 +127,9 @@ void MCSectionMachO::PrintSwitchToSection(const MCAsmInfo &MAI,
 
   // Check each attribute to see if we have it.
   char Separator = ',';
-  for (unsigned i = 0; SectionAttrDescriptors[i].AttrFlag; ++i) {
+  for (unsigned i = 0;
+       SectionAttrs != 0 && SectionAttrDescriptors[i].AttrFlag;
+       ++i) {
     // Check to see if we have this attribute.
     if ((SectionAttrDescriptors[i].AttrFlag & SectionAttrs) == 0)
       continue;
@@ -207,7 +211,6 @@ std::string MCSectionMachO::ParseSectionSpecifier(StringRef Spec,        // In.
            "between 1 and 16 characters";
 
   // If there is no comma after the section, we're done.
-  TAA = 0;
   StubSize = 0;
   if (Comma.second.empty())
     return "";
diff --git a/contrib/llvm/lib/MC/MCStreamer.cpp b/contrib/llvm/lib/MC/MCStreamer.cpp
index 3dcdba1..4b302c8 100644
--- a/contrib/llvm/lib/MC/MCStreamer.cpp
+++ b/contrib/llvm/lib/MC/MCStreamer.cpp
@@ -20,8 +20,8 @@
 using namespace llvm;
 
 MCStreamer::MCStreamer(MCContext &Ctx) : Context(Ctx) {
-  PrevSectionStack.push_back(NULL);
-  CurSectionStack.push_back(NULL);
+  const MCSection *section = NULL;
+  SectionStack.push_back(std::make_pair(section, section));
 }
 
 MCStreamer::~MCStreamer() {