MCAsmInfo.cpp revision 147272b8a70db7984a6bdfad3b5efabcb794a42e 
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  SunStyleELFSectionSwitchSyntax = false;
61  UsesELFSectionDirectiveForBSS = false;
62  AlignDirective = "\t.align\t";
63  AlignmentIsInBytes = true;
64  TextAlignFillValue = 0;
65  GPRel32Directive = 0;
66  GlobalDirective = "\t.globl\t";
67  HasSetDirective = true;
68  HasAggressiveSymbolFolding = true;
69  LCOMMDirectiveType = LCOMM::None;
70  COMMDirectiveAlignmentIsInBytes = true;
71  HasDotTypeDotSizeDirective = true;
72  HasSingleParameterDotFile = true;
73  HasNoDeadStrip = false;
74  HasSymbolResolver = false;
75  WeakRefDirective = 0;
76  WeakDefDirective = 0;
77  LinkOnceDirective = 0;
78  HiddenVisibilityAttr = MCSA_Hidden;
79  HiddenDeclarationVisibilityAttr = MCSA_Hidden;
80  ProtectedVisibilityAttr = MCSA_Protected;
81  HasLEB128 = false;
82  SupportsDebugInformation = false;
83  ExceptionsType = ExceptionHandling::None;
84  DwarfUsesInlineInfoSection = false;
85  DwarfRequiresRelocationForSectionOffset = true;
86  DwarfSectionOffsetDirective = 0;
87  DwarfUsesLabelOffsetForRanges = true;
88  DwarfRegNumForCFI = false;
89  HasMicrosoftFastStdCallMangling = false;
90
91  AsmTransCBE = 0;
92}
93
94MCAsmInfo::~MCAsmInfo() {
95}
96
97
98unsigned MCAsmInfo::getULEB128Size(unsigned Value) {
99  unsigned Size = 0;
100  do {
101    Value >>= 7;
102    Size += sizeof(int8_t);
103  } while (Value);
104  return Size;
105}
106
107unsigned MCAsmInfo::getSLEB128Size(int Value) {
108  unsigned Size = 0;
109  int Sign = Value >> (8 * sizeof(Value) - 1);
110  bool IsMore;
111
112  do {
113    unsigned Byte = Value & 0x7f;
114    Value >>= 7;
115    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
116    Size += sizeof(int8_t);
117  } while (IsMore);
118  return Size;
119}
120
121const MCExpr *
122MCAsmInfo::getExprForPersonalitySymbol(const MCSymbol *Sym,
123                                       unsigned Encoding,
124                                       MCStreamer &Streamer) const {
125  return getExprForFDESymbol(Sym, Encoding, Streamer);
126}
127
128const MCExpr *
129MCAsmInfo::getExprForFDESymbol(const MCSymbol *Sym,
130                               unsigned Encoding,
131                               MCStreamer &Streamer) const {
132  if (!(Encoding & dwarf::DW_EH_PE_pcrel))
133    return MCSymbolRefExpr::Create(Sym, Streamer.getContext());
134
135  MCContext &Context = Streamer.getContext();
136  const MCExpr *Res = MCSymbolRefExpr::Create(Sym, Context);
137  MCSymbol *PCSym = Context.CreateTempSymbol();
138  Streamer.EmitLabel(PCSym);
139  const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context);
140  return MCBinaryExpr::CreateSub(Res, PC, Context);
141}
142