ELFEmulation.cpp revision 37b74a387bb3993387029859c2d9d051c41c724e 
1//===- ELFEmulation.cpp ---------------------------------------------------===//
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#include "mcld/Target/ELFEmulation.h"
10#include "mcld/LinkerScript.h"
11#include "mcld/LinkerConfig.h"
12#include "mcld/Script/InputSectDesc.h"
13
14#include <llvm/Support/Host.h>
15
16namespace mcld {
17
18struct NameMap {
19  const char* from;  ///< the prefix of the input string. (match FROM*)
20  const char* to;    ///< the output string.
21  InputSectDesc::KeepPolicy policy;  /// mark whether the input is kept in GC
22};
23
24static const NameMap map[] = {
25    {".text*", ".text", InputSectDesc::NoKeep},
26    {".rodata*", ".rodata", InputSectDesc::NoKeep},
27    {".data.rel.ro.local*", ".data.rel.ro.local", InputSectDesc::NoKeep},
28    {".data.rel.ro*", ".data.rel.ro", InputSectDesc::NoKeep},
29    {".data*", ".data", InputSectDesc::NoKeep},
30    {".bss*", ".bss", InputSectDesc::NoKeep},
31    {".tdata*", ".tdata", InputSectDesc::NoKeep},
32    {".tbss*", ".tbss", InputSectDesc::NoKeep},
33    {".init", ".init", InputSectDesc::Keep},
34    {".fini", ".fini", InputSectDesc::Keep},
35    {".preinit_array*", ".preinit_array", InputSectDesc::Keep},
36    {".init_array*", ".init_array", InputSectDesc::Keep},
37    {".fini_array*", ".fini_array", InputSectDesc::Keep},
38    // TODO: Support DT_INIT_ARRAY for all constructors?
39    {".ctors*", ".ctors", InputSectDesc::Keep},
40    {".dtors*", ".dtors", InputSectDesc::Keep},
41    {".jcr", ".jcr", InputSectDesc::Keep},
42    // FIXME: in GNU ld, if we are creating a shared object .sdata2 and .sbss2
43    // sections would be handled differently.
44    {".sdata2*", ".sdata", InputSectDesc::NoKeep},
45    {".sbss2*", ".sbss", InputSectDesc::NoKeep},
46    {".sdata*", ".sdata", InputSectDesc::NoKeep},
47    {".sbss*", ".sbss", InputSectDesc::NoKeep},
48    {".lrodata*", ".lrodata", InputSectDesc::NoKeep},
49    {".ldata*", ".ldata", InputSectDesc::NoKeep},
50    {".lbss*", ".lbss", InputSectDesc::NoKeep},
51    {".gcc_except_table*", ".gcc_except_table", InputSectDesc::Keep},
52    {".gnu.linkonce.d.rel.ro.local*", ".data.rel.ro.local", InputSectDesc::NoKeep},  // NOLINT
53    {".gnu.linkonce.d.rel.ro*", ".data.rel.ro", InputSectDesc::NoKeep},
54    {".gnu.linkonce.r*", ".rodata", InputSectDesc::NoKeep},
55    {".gnu.linkonce.d*", ".data", InputSectDesc::NoKeep},
56    {".gnu.linkonce.b*", ".bss", InputSectDesc::NoKeep},
57    {".gnu.linkonce.sb2*", ".sbss", InputSectDesc::NoKeep},
58    {".gnu.linkonce.sb*", ".sbss", InputSectDesc::NoKeep},
59    {".gnu.linkonce.s2*", ".sdata", InputSectDesc::NoKeep},
60    {".gnu.linkonce.s*", ".sdata", InputSectDesc::NoKeep},
61    {".gnu.linkonce.wi*", ".debug_info", InputSectDesc::NoKeep},
62    {".gnu.linkonce.td*", ".tdata", InputSectDesc::NoKeep},
63    {".gnu.linkonce.tb*", ".tbss", InputSectDesc::NoKeep},
64    {".gnu.linkonce.t*", ".text", InputSectDesc::NoKeep},
65    {".gnu.linkonce.lr*", ".lrodata", InputSectDesc::NoKeep},
66    {".gnu.linkonce.lb*", ".lbss", InputSectDesc::NoKeep},
67    {".gnu.linkonce.l*", ".ldata", InputSectDesc::NoKeep},
68};
69
70// FIXME: LinkerConfig& pConfig should be constant
71bool MCLDEmulateELF(LinkerScript& pScript, LinkerConfig& pConfig) {
72  // set up section map
73  if (pConfig.options().getScriptList().empty() &&
74      pConfig.codeGenType() != LinkerConfig::Object) {
75    const unsigned int map_size = (sizeof(map) / sizeof(map[0]));
76    for (unsigned int i = 0; i < map_size; ++i) {
77      std::pair<SectionMap::mapping, bool> res =
78          pScript.sectionMap().insert(map[i].from, map[i].to, map[i].policy);
79      if (!res.second)
80        return false;
81    }
82  } else {
83    // FIXME: this is the hack to help assignment processing in current
84    // implementation.
85    pScript.sectionMap().insert("", "");
86  }
87
88  if (!pConfig.options().nostdlib()) {
89    // TODO: check if user sets the default search path instead via -Y option
90    // set up default search path
91    switch (pConfig.targets().triple().getOS()) {
92      case llvm::Triple::NetBSD:
93        pScript.directories().insert("=/usr/lib");
94        break;
95      case llvm::Triple::Win32:
96        pScript.directories().insert("=/mingw/lib");
97        break;
98      default:
99        pScript.directories().insert("=/lib");
100        pScript.directories().insert("=/usr/lib");
101        break;
102    }
103  }
104  return true;
105}
106
107}  // namespace mcld
108