lib/Target/TargetAsmInfo.cpp

   1 //===-- TargetAsmInfo.cpp - Asm Info ---------------------------------------==//
   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 defines target asm properties related what form asm statements
  11 // should take.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/Target/TargetAsmInfo.h"
  16 #include "llvm/Support/Dwarf.h"
  17 #include <cctype>
  18 #include <cstring>
  19
  20 using namespace llvm;
  21
  22 TargetAsmInfo::TargetAsmInfo() :
  23   TextSection("\t.text"),
  24   DataSection("\t.data"),
  25   BSSSection("\t.bss"),
  26   TLSDataSection("\t.section .tdata,\"awT\",@progbits"),
  27   TLSBSSSection("\t.section .tbss,\"awT\",@nobits"),
  28   ZeroFillDirective(0),
  29   NonexecutableStackDirective(0),
  30   NeedsSet(false),
  31   MaxInstLength(4),
  32   PCSymbol("$"),
  33   SeparatorChar(';'),
  34   CommentString("#"),
  35   GlobalPrefix(""),
  36   PrivateGlobalPrefix("."),
  37   JumpTableSpecialLabelPrefix(0),
  38   GlobalVarAddrPrefix(""),
  39   GlobalVarAddrSuffix(""),
  40   FunctionAddrPrefix(""),
  41   FunctionAddrSuffix(""),
  42   PersonalityPrefix(""),
  43   PersonalitySuffix(""),
  44   NeedsIndirectEncoding(false),
  45   InlineAsmStart("#APP"),
  46   InlineAsmEnd("#NO_APP"),
  47   AssemblerDialect(0),
  48   ZeroDirective("\t.zero\t"),
  49   ZeroDirectiveSuffix(0),
  50   AsciiDirective("\t.ascii\t"),
  51   AscizDirective("\t.asciz\t"),
  52   Data8bitsDirective("\t.byte\t"),
  53   Data16bitsDirective("\t.short\t"),
  54   Data32bitsDirective("\t.long\t"),
  55   Data64bitsDirective("\t.quad\t"),
  56   AlignDirective("\t.align\t"),
  57   AlignmentIsInBytes(true),
  58   TextAlignFillValue(0),
  59   SwitchToSectionDirective("\t.section\t"),
  60   TextSectionStartSuffix(""),
  61   DataSectionStartSuffix(""),
  62   SectionEndDirectiveSuffix(0),
  63   ConstantPoolSection("\t.section .rodata"),
  64   JumpTableDataSection("\t.section .rodata"),
  65   JumpTableDirective(0),
  66   CStringSection(0),
  67   StaticCtorsSection("\t.section .ctors,\"aw\",@progbits"),
  68   StaticDtorsSection("\t.section .dtors,\"aw\",@progbits"),
  69   FourByteConstantSection(0),
  70   EightByteConstantSection(0),
  71   SixteenByteConstantSection(0),
  72   ReadOnlySection(0),
  73   GlobalDirective("\t.globl\t"),
  74   SetDirective(0),
  75   LCOMMDirective(0),
  76   COMMDirective("\t.comm\t"),
  77   COMMDirectiveTakesAlignment(true),
  78   HasDotTypeDotSizeDirective(true),
  79   UsedDirective(0),
  80   WeakRefDirective(0),
  81   WeakDefDirective(0),
  82   HiddenDirective("\t.hidden\t"),
  83   ProtectedDirective("\t.protected\t"),
  84   AbsoluteDebugSectionOffsets(false),
  85   AbsoluteEHSectionOffsets(false),
  86   HasLEB128(false),
  87   HasDotLocAndDotFile(false),
  88   SupportsDebugInformation(false),
  89   SupportsExceptionHandling(false),
  90   DwarfRequiresFrameSection(true),
  91   GlobalEHDirective(0),
  92   SupportsWeakOmittedEHFrame(true),
  93   DwarfSectionOffsetDirective(0),
  94   DwarfAbbrevSection(".debug_abbrev"),
  95   DwarfInfoSection(".debug_info"),
  96   DwarfLineSection(".debug_line"),
  97   DwarfFrameSection(".debug_frame"),
  98   DwarfPubNamesSection(".debug_pubnames"),
  99   DwarfPubTypesSection(".debug_pubtypes"),
 100   DwarfStrSection(".debug_str"),
 101   DwarfLocSection(".debug_loc"),
 102   DwarfARangesSection(".debug_aranges"),
 103   DwarfRangesSection(".debug_ranges"),
 104   DwarfMacInfoSection(".debug_macinfo"),
 105   DwarfEHFrameSection(".eh_frame"),
 106   DwarfExceptionSection(".gcc_except_table"),
 107   AsmTransCBE(0) {
 108 }
 109
 110 TargetAsmInfo::~TargetAsmInfo() {
 111 }
 112
 113 /// Measure the specified inline asm to determine an approximation of its
 114 /// length.
 115 /// Comments (which run till the next SeparatorChar or newline) do not
 116 /// count as an instruction.
 117 /// Any other non-whitespace text is considered an instruction, with
 118 /// multiple instructions separated by SeparatorChar or newlines.
 119 /// Variable-length instructions are not handled here; this function
 120 /// may be overloaded in the target code to do that.
 121 unsigned TargetAsmInfo::getInlineAsmLength(const char *Str) const {
 122   // Count the number of instructions in the asm.
 123   bool atInsnStart = true;
 124   unsigned Length = 0;
 125   for (; *Str; ++Str) {
 126     if (*Str == '\n' || *Str == SeparatorChar)
 127       atInsnStart = true;
 128     if (atInsnStart && !isspace(*Str)) {
 129       Length += MaxInstLength;
 130       atInsnStart = false;
 131     }
 132     if (atInsnStart && strncmp(Str, CommentString, strlen(CommentString))==0)
 133       atInsnStart = false;
 134   }
 135
 136   return Length;
 137 }
 138
 139 unsigned TargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
 140                                               bool Global) const {
 141   return dwarf::DW_EH_PE_absptr;
 142 }
 143