lib/Target/X86/X86TargetAsmInfo.cpp

   1 //===-- X86TargetAsmInfo.cpp - X86 asm properties ---------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains the declarations of the X86TargetAsmInfo properties.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "X86TargetAsmInfo.h"
  15 #include "X86TargetMachine.h"
  16 #include "X86Subtarget.h"
  17 #include "llvm/DerivedTypes.h"
  18 #include "llvm/InlineAsm.h"
  19 #include "llvm/Instructions.h"
  20 #include "llvm/Intrinsics.h"
  21 #include "llvm/Module.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 #include "llvm/Support/Dwarf.h"
  24 #include "llvm/Support/ErrorHandling.h"
  25
  26 using namespace llvm;
  27 using namespace llvm::dwarf;
  28
  29 const char *const llvm::x86_asm_table[] = {
  30   "{si}", "S",
  31   "{di}", "D",
  32   "{ax}", "a",
  33   "{cx}", "c",
  34   "{memory}", "memory",
  35   "{flags}", "",
  36   "{dirflag}", "",
  37   "{fpsr}", "",
  38   "{cc}", "cc",
  39   0,0};
  40
  41 X86DarwinTargetAsmInfo::X86DarwinTargetAsmInfo(const X86TargetMachine &TM):
  42   X86TargetAsmInfo<DarwinTargetAsmInfo>(TM) {
  43   const X86Subtarget *Subtarget = &TM.getSubtarget<X86Subtarget>();
  44   bool is64Bit = Subtarget->is64Bit();
  45
  46   AlignmentIsInBytes = false;
  47   TextAlignFillValue = 0x90;
  48
  49
  50   if (!is64Bit)
  51     Data64bitsDirective = 0;       // we can't emit a 64-bit unit
  52   ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
  53   ZeroFillDirective = "\t.zerofill\t";  // Uses .zerofill
  54   if (TM.getRelocationModel() != Reloc::Static)
  55     ConstantPoolSection = "\t.const_data";
  56   else
  57     ConstantPoolSection = "\t.const\n";
  58   // FIXME: Why don't we always use this section?
  59   if (is64Bit)
  60     SixteenByteConstantSection = getUnnamedSection("\t.literal16\n",
  61                                                    SectionFlags::Mergeable);
  62   LCOMMDirective = "\t.lcomm\t";
  63
  64   // Leopard and above support aligned common symbols.
  65   COMMDirectiveTakesAlignment = (Subtarget->getDarwinVers() >= 9);
  66   HasDotTypeDotSizeDirective = false;
  67
  68   if (is64Bit) {
  69     PersonalityPrefix = "";
  70     PersonalitySuffix = "+4@GOTPCREL";
  71   } else {
  72     PersonalityPrefix = "L";
  73     PersonalitySuffix = "$non_lazy_ptr";
  74   }
  75
  76   InlineAsmStart = "## InlineAsm Start";
  77   InlineAsmEnd = "## InlineAsm End";
  78   CommentString = "##";
  79   SetDirective = "\t.set";
  80   PCSymbol = ".";
  81   UsedDirective = "\t.no_dead_strip\t";
  82   ProtectedDirective = "\t.globl\t";
  83
  84   SupportsDebugInformation = true;
  85   DwarfDebugInlineSection = ".section __DWARF,__debug_inlined,regular,debug";
  86   DwarfUsesInlineInfoSection = true;
  87
  88   // Exceptions handling
  89   SupportsExceptionHandling = true;
  90   GlobalEHDirective = "\t.globl\t";
  91   SupportsWeakOmittedEHFrame = false;
  92   AbsoluteEHSectionOffsets = false;
  93   DwarfEHFrameSection =
  94   ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
  95   DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
  96 }
  97
  98 unsigned
  99 X86DarwinTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
 100                                               bool Global) const {
 101   if (Reason == DwarfEncoding::Functions && Global)
 102     return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
 103   else if (Reason == DwarfEncoding::CodeLabels || !Global)
 104     return DW_EH_PE_pcrel;
 105   else
 106     return DW_EH_PE_absptr;
 107 }
 108
 109 const char *
 110 X86DarwinTargetAsmInfo::getEHGlobalPrefix() const
 111 {
 112   const X86Subtarget* Subtarget = &TM.getSubtarget<X86Subtarget>();
 113   if (Subtarget->getDarwinVers() > 9)
 114     return PrivateGlobalPrefix;
 115   else
 116     return "";
 117 }
 118
 119 X86ELFTargetAsmInfo::X86ELFTargetAsmInfo(const X86TargetMachine &TM):
 120   X86TargetAsmInfo<ELFTargetAsmInfo>(TM) {
 121
 122   CStringSection = ".rodata.str";
 123   PrivateGlobalPrefix = ".L";
 124   WeakRefDirective = "\t.weak\t";
 125   SetDirective = "\t.set\t";
 126   PCSymbol = ".";
 127
 128   // Set up DWARF directives
 129   HasLEB128 = true;  // Target asm supports leb128 directives (little-endian)
 130
 131   BSSSection_ = getUnnamedSection("\t.bss",
 132                                   SectionFlags::Writable | SectionFlags::BSS);
 133
 134   // Debug Information
 135   AbsoluteDebugSectionOffsets = true;
 136   SupportsDebugInformation = true;
 137   DwarfAbbrevSection =  "\t.section\t.debug_abbrev,\"\",@progbits";
 138   DwarfInfoSection =    "\t.section\t.debug_info,\"\",@progbits";
 139   DwarfLineSection =    "\t.section\t.debug_line,\"\",@progbits";
 140   DwarfFrameSection =   "\t.section\t.debug_frame,\"\",@progbits";
 141   DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
 142   DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
 143   DwarfStrSection =     "\t.section\t.debug_str,\"\",@progbits";
 144   DwarfLocSection =     "\t.section\t.debug_loc,\"\",@progbits";
 145   DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
 146   DwarfRangesSection =  "\t.section\t.debug_ranges,\"\",@progbits";
 147   DwarfMacroInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
 148
 149   // Exceptions handling
 150   SupportsExceptionHandling = true;
 151   AbsoluteEHSectionOffsets = false;
 152   DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
 153   DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
 154
 155   // On Linux we must declare when we can use a non-executable stack.
 156   if (TM.getSubtarget<X86Subtarget>().isLinux())
 157     NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
 158 }
 159
 160 unsigned
 161 X86ELFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
 162                                            bool Global) const {
 163   CodeModel::Model CM = TM.getCodeModel();
 164   bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
 165
 166   if (TM.getRelocationModel() == Reloc::PIC_) {
 167     unsigned Format = 0;
 168
 169     if (!is64Bit)
 170       // 32 bit targets always encode pointers as 4 bytes
 171       Format = DW_EH_PE_sdata4;
 172     else {
 173       // 64 bit targets encode pointers in 4 bytes iff:
 174       // - code model is small OR
 175       // - code model is medium and we're emitting externally visible symbols
 176       //   or any code symbols
 177       if (CM == CodeModel::Small ||
 178           (CM == CodeModel::Medium && (Global ||
 179                                        Reason != DwarfEncoding::Data)))
 180         Format = DW_EH_PE_sdata4;
 181       else
 182         Format = DW_EH_PE_sdata8;
 183     }
 184
 185     if (Global)
 186       Format |= DW_EH_PE_indirect;
 187
 188     return (Format | DW_EH_PE_pcrel);
 189   } else {
 190     if (is64Bit &&
 191         (CM == CodeModel::Small ||
 192          (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
 193       return DW_EH_PE_udata4;
 194     else
 195       return DW_EH_PE_absptr;
 196   }
 197 }
 198
 199 X86COFFTargetAsmInfo::X86COFFTargetAsmInfo(const X86TargetMachine &TM):
 200   X86GenericTargetAsmInfo(TM) {
 201
 202   GlobalPrefix = "_";
 203   LCOMMDirective = "\t.lcomm\t";
 204   COMMDirectiveTakesAlignment = false;
 205   HasDotTypeDotSizeDirective = false;
 206   HasSingleParameterDotFile = false;
 207   StaticCtorsSection = "\t.section .ctors,\"aw\"";
 208   StaticDtorsSection = "\t.section .dtors,\"aw\"";
 209   HiddenDirective = NULL;
 210   PrivateGlobalPrefix = "L";  // Prefix for private global symbols
 211   WeakRefDirective = "\t.weak\t";
 212   SetDirective = "\t.set\t";
 213
 214   // Set up DWARF directives
 215   HasLEB128 = true;  // Target asm supports leb128 directives (little-endian)
 216   AbsoluteDebugSectionOffsets = true;
 217   AbsoluteEHSectionOffsets = false;
 218   SupportsDebugInformation = true;
 219   DwarfSectionOffsetDirective = "\t.secrel32\t";
 220   DwarfAbbrevSection =  "\t.section\t.debug_abbrev,\"dr\"";
 221   DwarfInfoSection =    "\t.section\t.debug_info,\"dr\"";
 222   DwarfLineSection =    "\t.section\t.debug_line,\"dr\"";
 223   DwarfFrameSection =   "\t.section\t.debug_frame,\"dr\"";
 224   DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
 225   DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
 226   DwarfStrSection =     "\t.section\t.debug_str,\"dr\"";
 227   DwarfLocSection =     "\t.section\t.debug_loc,\"dr\"";
 228   DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
 229   DwarfRangesSection =  "\t.section\t.debug_ranges,\"dr\"";
 230   DwarfMacroInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
 231 }
 232
 233 unsigned
 234 X86COFFTargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
 235                                             bool Global) const {
 236   CodeModel::Model CM = TM.getCodeModel();
 237   bool is64Bit = TM.getSubtarget<X86Subtarget>().is64Bit();
 238
 239   if (TM.getRelocationModel() == Reloc::PIC_) {
 240     unsigned Format = 0;
 241
 242     if (!is64Bit)
 243       // 32 bit targets always encode pointers as 4 bytes
 244       Format = DW_EH_PE_sdata4;
 245     else {
 246       // 64 bit targets encode pointers in 4 bytes iff:
 247       // - code model is small OR
 248       // - code model is medium and we're emitting externally visible symbols
 249       //   or any code symbols
 250       if (CM == CodeModel::Small ||
 251           (CM == CodeModel::Medium && (Global ||
 252                                        Reason != DwarfEncoding::Data)))
 253         Format = DW_EH_PE_sdata4;
 254       else
 255         Format = DW_EH_PE_sdata8;
 256     }
 257
 258     if (Global)
 259       Format |= DW_EH_PE_indirect;
 260
 261     return (Format | DW_EH_PE_pcrel);
 262   }
 263
 264   if (is64Bit &&
 265       (CM == CodeModel::Small ||
 266        (CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
 267     return DW_EH_PE_udata4;
 268   return DW_EH_PE_absptr;
 269 }
 270
 271 const char *X86COFFTargetAsmInfo::
 272 getSectionPrefixForUniqueGlobal(SectionKind Kind) const {
 273   if (Kind.isText())
 274     return ".text$linkonce";
 275   if (Kind.isWriteable())
 276     return ".data$linkonce";
 277   return ".rdata$linkonce";
 278 }
 279
 280
 281 void X86COFFTargetAsmInfo::getSectionFlags(unsigned Flags,
 282                                            SmallVectorImpl<char> &Str) const {
 283   // FIXME: Inefficient.
 284   std::string Res = ",\"";
 285   if (Flags & SectionFlags::Code)
 286     Res += 'x';
 287   if (Flags & SectionFlags::Writable)
 288     Res += 'w';
 289   Res += "\"";
 290
 291   Str.append(Res.begin(), Res.end());
 292 }
 293
 294 X86WinTargetAsmInfo::X86WinTargetAsmInfo(const X86TargetMachine &TM):
 295   X86GenericTargetAsmInfo(TM) {
 296   GlobalPrefix = "_";
 297   CommentString = ";";
 298
 299   InlineAsmStart = "; InlineAsm Start";
 300   InlineAsmEnd   = "; InlineAsm End";
 301
 302   PrivateGlobalPrefix = "$";
 303   AlignDirective = "\tALIGN\t";
 304   ZeroDirective = "\tdb\t";
 305   ZeroDirectiveSuffix = " dup(0)";
 306   AsciiDirective = "\tdb\t";
 307   AscizDirective = 0;
 308   Data8bitsDirective = "\tdb\t";
 309   Data16bitsDirective = "\tdw\t";
 310   Data32bitsDirective = "\tdd\t";
 311   Data64bitsDirective = "\tdq\t";
 312   HasDotTypeDotSizeDirective = false;
 313   HasSingleParameterDotFile = false;
 314
 315   AlignmentIsInBytes = true;
 316
 317   TextSection = getUnnamedSection("_text", SectionFlags::Code);
 318   DataSection = getUnnamedSection("_data", SectionFlags::Writable);
 319
 320   JumpTableDataSection = NULL;
 321   SwitchToSectionDirective = "";
 322   TextSectionStartSuffix = "\tSEGMENT PARA 'CODE'";
 323   DataSectionStartSuffix = "\tSEGMENT PARA 'DATA'";
 324   SectionEndDirectiveSuffix = "\tends\n";
 325 }
 326
 327 // Instantiate default implementation.
 328 TEMPLATE_INSTANTIATION(class X86TargetAsmInfo<TargetAsmInfo>);