GNUInfo.h revision 533eae20118036f425f27bf0536ef0ccbb090b65 
1//===- GNUInfo.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_TARGET_GNUINFO_H
10#define MCLD_TARGET_GNUINFO_H
11#include <llvm/ADT/Triple.h>
12#include <llvm/Support/ELF.h>
13
14namespace mcld {
15
16/** \class GNUInfo
17 *  \brief GNUInfo records ELF-dependent and target-dependnet data fields
18 */
19class GNUInfo
20{
21public:
22  GNUInfo(const llvm::Triple& pTriple);
23
24  virtual ~GNUInfo() { }
25
26  /// ELFVersion - the value of e_ident[EI_VERSION]
27  virtual uint8_t ELFVersion() const { return llvm::ELF::EV_CURRENT; }
28
29  /// The return value of machine() it the same as e_machine in the ELF header
30  virtual uint32_t machine() const = 0;
31
32  /// OSABI - the value of e_ident[EI_OSABI]
33  uint8_t OSABI() const;
34
35  /// ABIVersion - the value of e_ident[EI_ABIVRESION]
36  virtual uint8_t ABIVersion() const { return 0x0; }
37
38  /// defaultTextSegmentAddr - target should specify its own default start address
39  /// of the text segment. esp. for exec.
40  virtual uint64_t defaultTextSegmentAddr() const { return 0x0; }
41
42  /// flags - the value of ElfXX_Ehdr::e_flags
43  virtual uint64_t flags() const = 0;
44
45  /// entry - the symbol name of the entry point
46  virtual const char* entry() const { return "_start"; }
47
48  /// dyld - the name of the default dynamic linker
49  /// target may override this function if needed.
50  /// @ref gnu ld, bfd/elf32-i386.c:521
51  virtual const char* dyld() const { return "/usr/lib/libc.so.1"; }
52
53  /// isDefaultExecStack - target should specify whether the stack is default
54  /// executable. If target favors another choice, please override this function
55  virtual bool isDefaultExecStack() const { return true; }
56
57  /// commonPageSize - the common page size of the target machine, and we set it
58  /// to 4K here. If target favors the different size, please override this
59  virtual uint64_t commonPageSize() const { return 0x1000; }
60
61  /// abiPageSize - the abi page size of the target machine, and we set it to 4K
62  /// here. If target favors the different size, please override this function
63  virtual uint64_t abiPageSize() const { return 0x1000; }
64
65protected:
66  const llvm::Triple& m_Triple;
67};
68
69} // namespace of mcld
70
71#endif
72
73