lib/MC/MCContext.cpp

   1 //===- lib/MC/MCContext.cpp - Machine Code Context ------------------------===//
   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 #include "llvm/MC/MCContext.h"
  11
  12 #include "llvm/MC/MCSection.h"
  13 #include "llvm/MC/MCSymbol.h"
  14 #include "llvm/MC/MCValue.h"
  15 using namespace llvm;
  16
  17 MCContext::MCContext() {
  18 }
  19
  20 MCContext::~MCContext() {
  21   // NOTE: The sections are all allocated out of a bump pointer allocator,
  22   // we don't need to free them here.
  23 }
  24
  25 MCSymbol *MCContext::CreateSymbol(const StringRef &Name) {
  26   assert(Name[0] != '\0' && "Normal symbols cannot be unnamed!");
  27
  28   // Create and bind the symbol, and ensure that names are unique.
  29   MCSymbol *&Entry = Symbols[Name];
  30   assert(!Entry && "Duplicate symbol definition!");
  31   return Entry = new (*this) MCSymbol(Name, false);
  32 }
  33
  34 MCSymbol *MCContext::GetOrCreateSymbol(const StringRef &Name) {
  35   MCSymbol *&Entry = Symbols[Name];
  36   if (Entry) return Entry;
  37
  38   return Entry = new (*this) MCSymbol(Name, false);
  39 }
  40
  41 MCSymbol *MCContext::CreateTemporarySymbol(const StringRef &Name) {
  42   // If unnamed, just create a symbol.
  43   if (Name.empty())
  44     new (*this) MCSymbol("", true);
  45
  46   // Otherwise create as usual.
  47   MCSymbol *&Entry = Symbols[Name];
  48   assert(!Entry && "Duplicate symbol definition!");
  49   return Entry = new (*this) MCSymbol(Name, true);
  50 }
  51
  52 MCSymbol *MCContext::LookupSymbol(const StringRef &Name) const {
  53   return Symbols.lookup(Name);
  54 }
  55
  56 void MCContext::ClearSymbolValue(const MCSymbol *Sym) {
  57   SymbolValues.erase(Sym);
  58 }
  59
  60 void MCContext::SetSymbolValue(const MCSymbol *Sym, const MCValue &Value) {
  61   SymbolValues[Sym] = Value;
  62 }
  63
  64 const MCValue *MCContext::GetSymbolValue(const MCSymbol *Sym) const {
  65   DenseMap<const MCSymbol*, MCValue>::iterator it = SymbolValues.find(Sym);
  66
  67   if (it == SymbolValues.end())
  68     return 0;
  69
  70   return &it->second;
  71 }