1 //===- lib/MC/MCContext.cpp - Machine Code Context ------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/MC/MCContext.h"
11 #include "llvm/MC/MCAsmInfo.h"
12 #include "llvm/MC/MCSectionMachO.h"
13 #include "llvm/MC/MCSectionELF.h"
14 #include "llvm/MC/MCSectionCOFF.h"
15 #include "llvm/MC/MCSymbol.h"
16 #include "llvm/ADT/SmallString.h"
17 #include "llvm/ADT/Twine.h"
20 typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
21 typedef StringMap<const MCSectionELF*> ELFUniqueMapTy;
22 typedef StringMap<const MCSectionCOFF*> COFFUniqueMapTy;
25 MCContext::MCContext(const MCAsmInfo &mai) : MAI(mai), NextUniqueID(0) {
31 MCContext::~MCContext() {
32 // NOTE: The symbols are all allocated out of a bump pointer allocator,
33 // we don't need to free them here.
35 // If we have the MachO uniquing map, free it.
36 delete (MachOUniqueMapTy*)MachOUniquingMap;
37 delete (ELFUniqueMapTy*)ELFUniquingMap;
38 delete (COFFUniqueMapTy*)COFFUniquingMap;
41 //===----------------------------------------------------------------------===//
42 // Symbol Manipulation
43 //===----------------------------------------------------------------------===//
45 MCSymbol *MCContext::GetOrCreateSymbol(StringRef Name) {
46 assert(!Name.empty() && "Normal symbols cannot be unnamed!");
48 // Determine whether this is an assembler temporary or normal label.
49 bool isTemporary = Name.startswith(MAI.getPrivateGlobalPrefix());
51 // Do the lookup and get the entire StringMapEntry. We want access to the
52 // key if we are creating the entry.
53 StringMapEntry<MCSymbol*> &Entry = Symbols.GetOrCreateValue(Name);
54 if (Entry.getValue()) return Entry.getValue();
56 // Ok, the entry doesn't already exist. Have the MCSymbol object itself refer
57 // to the copy of the string that is embedded in the StringMapEntry.
58 MCSymbol *Result = new (*this) MCSymbol(Entry.getKey(), isTemporary);
59 Entry.setValue(Result);
63 MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name) {
64 SmallString<128> NameSV;
65 Name.toVector(NameSV);
66 return GetOrCreateSymbol(NameSV.str());
69 MCSymbol *MCContext::CreateTempSymbol() {
70 return GetOrCreateSymbol(Twine(MAI.getPrivateGlobalPrefix()) +
71 "tmp" + Twine(NextUniqueID++));
74 MCSymbol *MCContext::LookupSymbol(StringRef Name) const {
75 return Symbols.lookup(Name);
78 //===----------------------------------------------------------------------===//
80 //===----------------------------------------------------------------------===//
82 const MCSectionMachO *MCContext::
83 getMachOSection(StringRef Segment, StringRef Section,
84 unsigned TypeAndAttributes,
85 unsigned Reserved2, SectionKind Kind) {
87 // We unique sections by their segment/section pair. The returned section
88 // may not have the same flags as the requested section, if so this should be
89 // diagnosed by the client as an error.
91 // Create the map if it doesn't already exist.
92 if (MachOUniquingMap == 0)
93 MachOUniquingMap = new MachOUniqueMapTy();
94 MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)MachOUniquingMap;
96 // Form the name to look up.
102 // Do the lookup, if we have a hit, return it.
103 const MCSectionMachO *&Entry = Map[Name.str()];
104 if (Entry) return Entry;
106 // Otherwise, return a new section.
107 return Entry = new (*this) MCSectionMachO(Segment, Section, TypeAndAttributes,
112 const MCSection *MCContext::
113 getELFSection(StringRef Section, unsigned Type, unsigned Flags,
114 SectionKind Kind, bool IsExplicit) {
115 if (ELFUniquingMap == 0)
116 ELFUniquingMap = new ELFUniqueMapTy();
117 ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)ELFUniquingMap;
119 // Do the lookup, if we have a hit, return it.
120 StringMapEntry<const MCSectionELF*> &Entry = Map.GetOrCreateValue(Section);
121 if (Entry.getValue()) return Entry.getValue();
123 MCSectionELF *Result = new (*this) MCSectionELF(Entry.getKey(), Type, Flags,
125 Entry.setValue(Result);
129 const MCSection *MCContext::
130 getCOFFSection(StringRef Section, unsigned Flags, SectionKind Kind) {
131 if (COFFUniquingMap == 0)
132 COFFUniquingMap = new COFFUniqueMapTy();
133 COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap;
135 // Do the lookup, if we have a hit, return it.
136 StringMapEntry<const MCSectionCOFF*> &Entry = Map.GetOrCreateValue(Section);
137 if (Entry.getValue()) return Entry.getValue();
139 MCSectionCOFF *Result = new (*this) MCSectionCOFF(Entry.getKey(), Flags,
142 Entry.setValue(Result);