ELFEmulation.cpp revision f33f6de54db174aa679a4b6d1e040d37e95541c0 
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
16using namespace 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{
26  {".text*", ".text", InputSectDesc::NoKeep},
27  {".rodata*", ".rodata", InputSectDesc::NoKeep},
28  {".data.rel.ro.local*", ".data.rel.ro.local", InputSectDesc::NoKeep},
29  {".data.rel.ro*", ".data.rel.ro", InputSectDesc::NoKeep},
30  {".data*", ".data", InputSectDesc::NoKeep},
31  {".bss*", ".bss", InputSectDesc::NoKeep},
32  {".tdata*", ".tdata", InputSectDesc::NoKeep},
33  {".tbss*", ".tbss", InputSectDesc::NoKeep},
34  {".init", ".init", InputSectDesc::Keep},
35  {".fini", ".fini", InputSectDesc::Keep},
36  {".preinit_array*", ".preinit_array", InputSectDesc::Keep},
37  {".init_array*", ".init_array", InputSectDesc::Keep},
38  {".fini_array*", ".fini_array", InputSectDesc::Keep},
39  // TODO: Support DT_INIT_ARRAY for all constructors?
40  {".ctors*", ".ctors", InputSectDesc::Keep},
41  {".dtors*", ".dtors", InputSectDesc::Keep},
42  {".jcr", ".jcr", InputSectDesc::Keep},
43  // FIXME: in GNU ld, if we are creating a shared object .sdata2 and .sbss2
44  // sections would be handled differently.
45  {".sdata2*", ".sdata", InputSectDesc::NoKeep},
46  {".sbss2*", ".sbss", InputSectDesc::NoKeep},
47  {".sdata*", ".sdata", InputSectDesc::NoKeep},
48  {".sbss*", ".sbss", InputSectDesc::NoKeep},
49  {".lrodata*", ".lrodata", InputSectDesc::NoKeep},
50  {".ldata*", ".ldata", InputSectDesc::NoKeep},
51  {".lbss*", ".lbss", InputSectDesc::NoKeep},
52  {".gcc_except_table*", ".gcc_except_table", InputSectDesc::Keep},
53  {".gnu.linkonce.d.rel.ro.local*", ".data.rel.ro.local", InputSectDesc::NoKeep},
54  {".gnu.linkonce.d.rel.ro*", ".data.rel.ro", InputSectDesc::NoKeep},
55  {".gnu.linkonce.r*", ".rodata", InputSectDesc::NoKeep},
56  {".gnu.linkonce.d*", ".data", InputSectDesc::NoKeep},
57  {".gnu.linkonce.b*", ".bss", InputSectDesc::NoKeep},
58  {".gnu.linkonce.sb2*", ".sbss", InputSectDesc::NoKeep},
59  {".gnu.linkonce.sb*", ".sbss", InputSectDesc::NoKeep},
60  {".gnu.linkonce.s2*", ".sdata", InputSectDesc::NoKeep},
61  {".gnu.linkonce.s*", ".sdata", InputSectDesc::NoKeep},
62  {".gnu.linkonce.wi*", ".debug_info", InputSectDesc::NoKeep},
63  {".gnu.linkonce.td*", ".tdata", InputSectDesc::NoKeep},
64  {".gnu.linkonce.tb*", ".tbss", InputSectDesc::NoKeep},
65  {".gnu.linkonce.t*", ".text", InputSectDesc::NoKeep},
66  {".gnu.linkonce.lr*", ".lrodata", InputSectDesc::NoKeep},
67  {".gnu.linkonce.lb*", ".lbss", InputSectDesc::NoKeep},
68  {".gnu.linkonce.l*", ".ldata", InputSectDesc::NoKeep},
69};
70
71bool mcld::MCLDEmulateELF(LinkerScript& pScript, LinkerConfig& pConfig)
72// FIXME: LinkerConfig& pConfig should be constant
73{
74  // set up section map
75  if (pConfig.options().getScriptList().empty() &&
76      pConfig.codeGenType() != LinkerConfig::Object) {
77    const unsigned int map_size =  (sizeof(map) / sizeof(map[0]) );
78    for (unsigned int i = 0; i < map_size; ++i) {
79      std::pair<SectionMap::mapping, bool> res =
80        pScript.sectionMap().insert(map[i].from, map[i].to, map[i].policy);
81      if (!res.second)
82        return false;
83    }
84  } else {
85    // FIXME: this is the hack to help assignment processing in current
86    // implementation.
87    pScript.sectionMap().insert("", "");
88  }
89
90  if (!pConfig.options().nostdlib()) {
91    // TODO: check if user sets the default search path instead via -Y option
92    // set up default search path
93    switch (pConfig.targets().triple().getOS()) {
94      case llvm::Triple::NetBSD:
95        pScript.directories().insert("=/usr/lib");
96        break;
97      case llvm::Triple::MinGW32:
98        pScript.directories().insert("=/mingw/lib");
99        break;
100      default:
101        pScript.directories().insert("=/lib");
102        pScript.directories().insert("=/usr/lib");
103        break;
104    }
105  }
106  return true;
107}
108
109