MCAsmInfo.cpp revision 226633 
1//===-- MCAsmInfo.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/MC/MCAsmInfo.h"
16#include "llvm/MC/MCContext.h"
17#include "llvm/MC/MCExpr.h"
18#include "llvm/MC/MCStreamer.h"
19#include "llvm/Support/DataTypes.h"
20#include "llvm/Support/Dwarf.h"
21#include <cctype>
22#include <cstring>
23using namespace llvm;
24
25MCAsmInfo::MCAsmInfo() {
26  PointerSize = 4;
27  IsLittleEndian = true;
28  StackGrowsUp = false;
29  HasSubsectionsViaSymbols = false;
30  HasMachoZeroFillDirective = false;
31  HasMachoTBSSDirective = false;
32  StructorOutputOrder = Structors::ReversePriorityOrder;
33  HasStaticCtorDtorReferenceInStaticMode = false;
34  LinkerRequiresNonEmptyDwarfLines = false;
35  MaxInstLength = 4;
36  PCSymbol = "$";
37  SeparatorString = ";";
38  CommentColumn = 40;
39  CommentString = "#";
40  LabelSuffix = ":";
41  GlobalPrefix = "";
42  PrivateGlobalPrefix = ".";
43  LinkerPrivateGlobalPrefix = "";
44  InlineAsmStart = "APP";
45  InlineAsmEnd = "NO_APP";
46  Code16Directive = ".code16";
47  Code32Directive = ".code32";
48  Code64Directive = ".code64";
49  AssemblerDialect = 0;
50  AllowQuotesInName = false;
51  AllowNameToStartWithDigit = false;
52  AllowPeriodsInName = true;
53  ZeroDirective = "\t.zero\t";
54  AsciiDirective = "\t.ascii\t";
55  AscizDirective = "\t.asciz\t";
56  Data8bitsDirective = "\t.byte\t";
57  Data16bitsDirective = "\t.short\t";
58  Data32bitsDirective = "\t.long\t";
59  Data64bitsDirective = "\t.quad\t";
60  DataBegin = "$d.";
61  CodeBegin = "$a.";
62  JT8Begin = "$d.";
63  JT16Begin = "$d.";
64  JT32Begin = "$d.";
65  SupportsDataRegions = false;
66  SunStyleELFSectionSwitchSyntax = false;
67  UsesELFSectionDirectiveForBSS = false;
68  AlignDirective = "\t.align\t";
69  AlignmentIsInBytes = true;
70  TextAlignFillValue = 0;
71  GPRel32Directive = 0;
72  GlobalDirective = "\t.globl\t";
73  HasSetDirective = true;
74  HasAggressiveSymbolFolding = true;
75  LCOMMDirectiveType = LCOMM::None;
76  COMMDirectiveAlignmentIsInBytes = true;
77  HasDotTypeDotSizeDirective = true;
78  HasSingleParameterDotFile = true;
79  HasNoDeadStrip = false;
80  HasSymbolResolver = false;
81  WeakRefDirective = 0;
82  WeakDefDirective = 0;
83  LinkOnceDirective = 0;
84  HiddenVisibilityAttr = MCSA_Hidden;
85  HiddenDeclarationVisibilityAttr = MCSA_Hidden;
86  ProtectedVisibilityAttr = MCSA_Protected;
87  HasLEB128 = false;
88  SupportsDebugInformation = false;
89  ExceptionsType = ExceptionHandling::None;
90  DwarfUsesInlineInfoSection = false;
91  DwarfRequiresRelocationForSectionOffset = true;
92  DwarfSectionOffsetDirective = 0;
93  DwarfUsesLabelOffsetForRanges = true;
94  DwarfRegNumForCFI = false;
95  HasMicrosoftFastStdCallMangling = false;
96
97  AsmTransCBE = 0;
98}
99
100MCAsmInfo::~MCAsmInfo() {
101}
102
103
104unsigned MCAsmInfo::getULEB128Size(unsigned Value) {
105  unsigned Size = 0;
106  do {
107    Value >>= 7;
108    Size += sizeof(int8_t);
109  } while (Value);
110  return Size;
111}
112
113unsigned MCAsmInfo::getSLEB128Size(int Value) {
114  unsigned Size = 0;
115  int Sign = Value >> (8 * sizeof(Value) - 1);
116  bool IsMore;
117
118  do {
119    unsigned Byte = Value & 0x7f;
120    Value >>= 7;
121    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
122    Size += sizeof(int8_t);
123  } while (IsMore);
124  return Size;
125}
126
127const MCExpr *
128MCAsmInfo::getExprForPersonalitySymbol(const MCSymbol *Sym,
129                                       unsigned Encoding,
130                                       MCStreamer &Streamer) const {
131  return getExprForFDESymbol(Sym, Encoding, Streamer);
132}
133
134const MCExpr *
135MCAsmInfo::getExprForFDESymbol(const MCSymbol *Sym,
136                               unsigned Encoding,
137                               MCStreamer &Streamer) const {
138  if (!(Encoding & dwarf::DW_EH_PE_pcrel))
139    return MCSymbolRefExpr::Create(Sym, Streamer.getContext());
140
141  MCContext &Context = Streamer.getContext();
142  const MCExpr *Res = MCSymbolRefExpr::Create(Sym, Context);
143  MCSymbol *PCSym = Context.CreateTempSymbol();
144  Streamer.EmitLabel(PCSym);
145  const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context);
146  return MCBinaryExpr::CreateSub(Res, PC, Context);
147}
148