lib/CodeGen/ObjectCodeEmitter.cpp

   1 //===-- llvm/CodeGen/ObjectCodeEmitter.cpp -------------------- -*- C++ -*-===//
   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/CodeGen/BinaryObject.h"
  11 #include "llvm/CodeGen/MachineBasicBlock.h"
  12 #include "llvm/CodeGen/MachineRelocation.h"
  13 #include "llvm/CodeGen/ObjectCodeEmitter.h"
  14
  15 //===----------------------------------------------------------------------===//
  16 //                       ObjectCodeEmitter Implementation
  17 //===----------------------------------------------------------------------===//
  18
  19 namespace llvm {
  20
  21 ObjectCodeEmitter::ObjectCodeEmitter() : BO(0) {}
  22 ObjectCodeEmitter::ObjectCodeEmitter(BinaryObject *bo) : BO(bo) {}
  23 ObjectCodeEmitter::~ObjectCodeEmitter() {}
  24
  25 /// setBinaryObject - set the BinaryObject we are writting to
  26 void ObjectCodeEmitter::setBinaryObject(BinaryObject *bo) { BO = bo; }
  27
  28 /// emitByte - This callback is invoked when a byte needs to be
  29 /// written to the data stream, without buffer overflow testing.
  30 void ObjectCodeEmitter::emitByte(uint8_t B) {
  31   BO->emitByte(B);
  32 }
  33
  34 /// emitWordLE - This callback is invoked when a 32-bit word needs to be
  35 /// written to the data stream in little-endian format.
  36 void ObjectCodeEmitter::emitWordLE(uint32_t W) {
  37   BO->emitWordLE(W);
  38 }
  39
  40 /// emitWordBE - This callback is invoked when a 32-bit word needs to be
  41 /// written to the data stream in big-endian format.
  42 void ObjectCodeEmitter::emitWordBE(uint32_t W) {
  43   BO->emitWordBE(W);
  44 }
  45
  46 /// emitDWordLE - This callback is invoked when a 64-bit word needs to be
  47 /// written to the data stream in little-endian format.
  48 void ObjectCodeEmitter::emitDWordLE(uint64_t W) {
  49   BO->emitDWordLE(W);
  50 }
  51
  52 /// emitDWordBE - This callback is invoked when a 64-bit word needs to be
  53 /// written to the data stream in big-endian format.
  54 void ObjectCodeEmitter::emitDWordBE(uint64_t W) {
  55   BO->emitDWordBE(W);
  56 }
  57
  58 /// emitAlignment - Align 'BO' to the necessary alignment boundary.
  59 void ObjectCodeEmitter::emitAlignment(unsigned Alignment /* 0 */,
  60                                       uint8_t fill /* 0 */) {
  61   BO->emitAlignment(Alignment, fill);
  62 }
  63
  64 /// emitULEB128Bytes - This callback is invoked when a ULEB128 needs to be
  65 /// written to the data stream.
  66 void ObjectCodeEmitter::emitULEB128Bytes(uint64_t Value) {
  67   BO->emitULEB128Bytes(Value);
  68 }
  69
  70 /// emitSLEB128Bytes - This callback is invoked when a SLEB128 needs to be
  71 /// written to the data stream.
  72 void ObjectCodeEmitter::emitSLEB128Bytes(uint64_t Value) {
  73   BO->emitSLEB128Bytes(Value);
  74 }
  75
  76 /// emitString - This callback is invoked when a String needs to be
  77 /// written to the data stream.
  78 void ObjectCodeEmitter::emitString(const std::string &String) {
  79   BO->emitString(String);
  80 }
  81
  82 /// getCurrentPCValue - This returns the address that the next emitted byte
  83 /// will be output to.
  84 uintptr_t ObjectCodeEmitter::getCurrentPCValue() const {
  85   return BO->getCurrentPCOffset();
  86 }
  87
  88 /// getCurrentPCOffset - Return the offset from the start of the emitted
  89 /// buffer that we are currently writing to.
  90 uintptr_t ObjectCodeEmitter::getCurrentPCOffset() const {
  91   return BO->getCurrentPCOffset();
  92 }
  93
  94 /// addRelocation - Whenever a relocatable address is needed, it should be
  95 /// noted with this interface.
  96 void ObjectCodeEmitter::addRelocation(const MachineRelocation& relocation) {
  97   BO->addRelocation(relocation);
  98 }
  99
 100 /// StartMachineBasicBlock - This should be called by the target when a new
 101 /// basic block is about to be emitted.  This way the MCE knows where the
 102 /// start of the block is, and can implement getMachineBasicBlockAddress.
 103 void ObjectCodeEmitter::StartMachineBasicBlock(MachineBasicBlock *MBB) {
 104   if (MBBLocations.size() <= (unsigned)MBB->getNumber())
 105     MBBLocations.resize((MBB->getNumber()+1)*2);
 106   MBBLocations[MBB->getNumber()] = getCurrentPCOffset();
 107 }
 108
 109 /// getMachineBasicBlockAddress - Return the address of the specified
 110 /// MachineBasicBlock, only usable after the label for the MBB has been
 111 /// emitted.
 112 uintptr_t
 113 ObjectCodeEmitter::getMachineBasicBlockAddress(MachineBasicBlock *MBB) const {
 114   assert(MBBLocations.size() > (unsigned)MBB->getNumber() &&
 115          MBBLocations[MBB->getNumber()] && "MBB not emitted!");
 116   return MBBLocations[MBB->getNumber()];
 117 }
 118
 119 /// getJumpTableEntryAddress - Return the address of the jump table with index
 120 /// 'Index' in the function that last called initJumpTableInfo.
 121 uintptr_t ObjectCodeEmitter::getJumpTableEntryAddress(unsigned Index) const {
 122   assert(JTLocations.size() > Index && "JT not emitted!");
 123   return JTLocations[Index];
 124 }
 125
 126 /// getConstantPoolEntryAddress - Return the address of the 'Index' entry in
 127 /// the constant pool that was last emitted with the emitConstantPool method.
 128 uintptr_t ObjectCodeEmitter::getConstantPoolEntryAddress(unsigned Index) const {
 129   assert(CPLocations.size() > Index && "CP not emitted!");
 130   return CPLocations[Index];
 131 }
 132
 133 /// getConstantPoolEntrySection - Return the section of the 'Index' entry in
 134 /// the constant pool that was last emitted with the emitConstantPool method.
 135 uintptr_t ObjectCodeEmitter::getConstantPoolEntrySection(unsigned Index) const {
 136   assert(CPSections.size() > Index && "CP not emitted!");
 137   return CPSections[Index];
 138 }
 139
 140 } // end namespace llvm
 141