EhFrameHdr.h revision 87f34658dec9097d987d254a990ea7f311bfc95f 
1//===- EhFrameHdr.h -------------------------------------------------------===//
2//
3//                     The MCLinker Project
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9#ifndef MCLD_LD_EHFRAMEHDR_H
10#define MCLD_LD_EHFRAMEHDR_H
11#ifdef ENABLE_UNITTEST
12#include <gtest.h>
13#endif
14#include <mcld/ADT/SizeTraits.h>
15#include <cassert>
16
17#include <mcld/LD/EhFrame.h>
18#include <mcld/Support/FileOutputBuffer.h>
19namespace mcld {
20
21class LDSection;
22class FileOutputBuffer;
23
24/** \class EhFrameHdr
25 *  \brief EhFrameHdr represents .eh_frame_hdr section.
26 *
27 *  @ref lsb core generic 4.1
28 *  .eh_frame_hdr section format
29 *  uint8_t : version
30 *  uint8_t : eh_frame_ptr_enc
31 *  uint8_t : fde_count_enc
32 *  uint8_t : table_enc
33 *  uint32_t : eh_frame_ptr
34 *  uint32_t : fde_count
35 *  __________________________ when fde_count > 0
36 *  <uint32_t, uint32_t>+ : binary search table
37 */
38class EhFrameHdr
39{
40public:
41  EhFrameHdr(LDSection& pEhFrameHdr, const LDSection& pEhFrame);
42
43  ~EhFrameHdr();
44
45  /// sizeOutput - base on the fde count to size output
46  void sizeOutput();
47
48  /// emitOutput - write out eh_frame_hdr
49  template<size_t size>
50  void emitOutput(FileOutputBuffer& pOutput)
51  { assert(false && "Call invalid EhFrameHdr::emitOutput"); }
52
53private:
54  /// computePCBegin - return the address of FDE's pc
55  /// @ref binutils gold: ehframe.cc:222
56  uint32_t computePCBegin(const EhFrame::FDE& pFDE,
57                          const MemoryRegion& pEhFrameRegion);
58
59private:
60  /// .eh_frame_hdr section
61  LDSection& m_EhFrameHdr;
62
63  /// eh_frame
64  const LDSection& m_EhFrame;
65};
66
67//===----------------------------------------------------------------------===//
68// Template Specification Functions
69//===----------------------------------------------------------------------===//
70/// emitOutput - write out eh_frame_hdr
71template<>
72void EhFrameHdr::emitOutput<32>(FileOutputBuffer& pOutput);
73
74} // namespace of mcld
75
76#endif
77
78