Commit | Line | Data |
---|---|---|
a2fb1b05 ILT |
1 | // layout.h -- lay out output file sections for gold -*- C++ -*- |
2 | ||
3 | #ifndef GOLD_LAYOUT_H | |
4 | #define GOLD_LAYOUT_H | |
5 | ||
6 | #include <list> | |
7 | #include <string> | |
8 | #include <utility> | |
9 | #include <vector> | |
10 | ||
a2fb1b05 ILT |
11 | #include "workqueue.h" |
12 | #include "object.h" | |
14b31740 | 13 | #include "dynobj.h" |
a2fb1b05 ILT |
14 | #include "stringpool.h" |
15 | ||
16 | namespace gold | |
17 | { | |
18 | ||
ead1e424 | 19 | class General_options; |
54dc6425 | 20 | class Input_objects; |
75f65a3e | 21 | class Symbol_table; |
ead1e424 | 22 | class Output_section_data; |
a2fb1b05 | 23 | class Output_section; |
75f65a3e | 24 | class Output_section_headers; |
a2fb1b05 | 25 | class Output_segment; |
54dc6425 | 26 | class Output_data; |
a3ad94ed | 27 | class Output_data_dynamic; |
61ba1cf9 | 28 | class Target; |
a2fb1b05 | 29 | |
92e059d8 ILT |
30 | // This task function handles mapping the input sections to output |
31 | // sections and laying them out in memory. | |
a2fb1b05 | 32 | |
92e059d8 | 33 | class Layout_task_runner : public Task_function_runner |
a2fb1b05 ILT |
34 | { |
35 | public: | |
36 | // OPTIONS is the command line options, INPUT_OBJECTS is the list of | |
92e059d8 ILT |
37 | // input objects, SYMTAB is the symbol table, LAYOUT is the layout |
38 | // object. | |
39 | Layout_task_runner(const General_options& options, | |
40 | const Input_objects* input_objects, | |
41 | Symbol_table* symtab, | |
42 | Layout* layout) | |
75f65a3e | 43 | : options_(options), input_objects_(input_objects), symtab_(symtab), |
92e059d8 | 44 | layout_(layout) |
a2fb1b05 ILT |
45 | { } |
46 | ||
92e059d8 | 47 | // Run the operation. |
a2fb1b05 ILT |
48 | void |
49 | run(Workqueue*); | |
50 | ||
51 | private: | |
92e059d8 ILT |
52 | Layout_task_runner(const Layout_task_runner&); |
53 | Layout_task_runner& operator=(const Layout_task_runner&); | |
a2fb1b05 ILT |
54 | |
55 | const General_options& options_; | |
54dc6425 | 56 | const Input_objects* input_objects_; |
75f65a3e | 57 | Symbol_table* symtab_; |
12e14209 | 58 | Layout* layout_; |
a2fb1b05 ILT |
59 | }; |
60 | ||
61 | // This class handles the details of laying out input sections. | |
62 | ||
63 | class Layout | |
64 | { | |
65 | public: | |
54dc6425 ILT |
66 | Layout(const General_options& options); |
67 | ||
ead1e424 ILT |
68 | // Given an input section SHNDX, named NAME, with data in SHDR, from |
69 | // the object file OBJECT, return the output section where this | |
70 | // input section should go. Set *OFFSET to the offset within the | |
71 | // output section. | |
a2fb1b05 ILT |
72 | template<int size, bool big_endian> |
73 | Output_section* | |
f6ce93d6 | 74 | layout(Relobj *object, unsigned int shndx, const char* name, |
a2fb1b05 ILT |
75 | const elfcpp::Shdr<size, big_endian>& shdr, off_t* offset); |
76 | ||
ead1e424 ILT |
77 | // Add an Output_section_data to the layout. This is used for |
78 | // special sections like the GOT section. | |
79 | void | |
80 | add_output_section_data(const char* name, elfcpp::Elf_Word type, | |
81 | elfcpp::Elf_Xword flags, | |
82 | Output_section_data*); | |
83 | ||
a3ad94ed ILT |
84 | // Create dynamic sections if necessary. |
85 | void | |
86 | create_initial_dynamic_sections(const Input_objects*, Symbol_table*); | |
87 | ||
61ba1cf9 ILT |
88 | // Return the Stringpool used for symbol names. |
89 | const Stringpool* | |
90 | sympool() const | |
91 | { return &this->sympool_; } | |
92 | ||
16649710 ILT |
93 | // Return the Stringpool used for dynamic symbol names and dynamic |
94 | // tags. | |
95 | const Stringpool* | |
96 | dynpool() const | |
97 | { return &this->dynpool_; } | |
98 | ||
a2fb1b05 ILT |
99 | // Return whether a section is a .gnu.linkonce section, given the |
100 | // section name. | |
101 | static inline bool | |
102 | is_linkonce(const char* name) | |
103 | { return strncmp(name, ".gnu.linkonce", sizeof(".gnu.linkonce") - 1) == 0; } | |
104 | ||
105 | // Record the signature of a comdat section, and return whether to | |
106 | // include it in the link. The GROUP parameter is true for a | |
107 | // section group signature, false for a signature derived from a | |
108 | // .gnu.linkonce section. | |
109 | bool | |
110 | add_comdat(const char*, bool group); | |
111 | ||
54dc6425 | 112 | // Finalize the layout after all the input sections have been added. |
75f65a3e ILT |
113 | off_t |
114 | finalize(const Input_objects*, Symbol_table*); | |
54dc6425 | 115 | |
16649710 ILT |
116 | // Return the TLS segment. This will return NULL if there isn't |
117 | // one. | |
92e059d8 ILT |
118 | Output_segment* |
119 | tls_segment() const | |
120 | { return this->tls_segment_; } | |
121 | ||
16649710 ILT |
122 | // Return the normal symbol table. |
123 | Output_section* | |
124 | symtab_section() const | |
125 | { | |
126 | gold_assert(this->symtab_section_ != NULL); | |
127 | return this->symtab_section_; | |
128 | } | |
129 | ||
130 | // Return the dynamic symbol table. | |
131 | Output_section* | |
132 | dynsym_section() const | |
133 | { | |
134 | gold_assert(this->dynsym_section_ != NULL); | |
135 | return this->dynsym_section_; | |
136 | } | |
137 | ||
138 | // Return the dynamic tags. | |
139 | Output_data_dynamic* | |
140 | dynamic_data() const | |
141 | { return this->dynamic_data_; } | |
142 | ||
61ba1cf9 ILT |
143 | // Write out data not associated with an input file or the symbol |
144 | // table. | |
145 | void | |
a3ad94ed | 146 | write_data(const Symbol_table*, const Target*, Output_file*) const; |
61ba1cf9 | 147 | |
ead1e424 ILT |
148 | // Return an output section named NAME, or NULL if there is none. |
149 | Output_section* | |
150 | find_output_section(const char* name) const; | |
151 | ||
152 | // Return an output segment of type TYPE, with segment flags SET set | |
153 | // and segment flags CLEAR clear. Return NULL if there is none. | |
154 | Output_segment* | |
155 | find_output_segment(elfcpp::PT type, elfcpp::Elf_Word set, | |
156 | elfcpp::Elf_Word clear) const; | |
157 | ||
54dc6425 ILT |
158 | // The list of segments. |
159 | ||
160 | typedef std::vector<Output_segment*> Segment_list; | |
161 | ||
162 | // The list of sections not attached to a segment. | |
163 | ||
a3ad94ed | 164 | typedef std::vector<Output_section*> Section_list; |
54dc6425 ILT |
165 | |
166 | // The list of information to write out which is not attached to | |
167 | // either a section or a segment. | |
a3ad94ed | 168 | typedef std::vector<Output_data*> Data_list; |
54dc6425 | 169 | |
a2fb1b05 ILT |
170 | private: |
171 | Layout(const Layout&); | |
172 | Layout& operator=(const Layout&); | |
173 | ||
174 | // Mapping from .gnu.linkonce section names to output section names. | |
175 | struct Linkonce_mapping | |
176 | { | |
177 | const char* from; | |
178 | int fromlen; | |
179 | const char* to; | |
ead1e424 | 180 | int tolen; |
a2fb1b05 ILT |
181 | }; |
182 | static const Linkonce_mapping linkonce_mapping[]; | |
183 | static const int linkonce_mapping_count; | |
184 | ||
75f65a3e ILT |
185 | // Find the first read-only PT_LOAD segment, creating one if |
186 | // necessary. | |
187 | Output_segment* | |
188 | find_first_load_seg(); | |
189 | ||
54dc6425 ILT |
190 | // Create the output sections for the symbol table. |
191 | void | |
16649710 ILT |
192 | create_symtab_sections(int size, const Input_objects*, Symbol_table*, |
193 | off_t*); | |
54dc6425 | 194 | |
75f65a3e ILT |
195 | // Create the .shstrtab section. |
196 | Output_section* | |
197 | create_shstrtab(); | |
198 | ||
199 | // Create the section header table. | |
200 | Output_section_headers* | |
61ba1cf9 | 201 | create_shdrs(int size, bool big_endian, off_t*); |
54dc6425 | 202 | |
dbe717ef ILT |
203 | // Create the dynamic symbol table. |
204 | void | |
14b31740 ILT |
205 | create_dynamic_symtab(const Target*, Symbol_table*, Output_section** pdynstr, |
206 | unsigned int* plocal_dynamic_count, | |
207 | std::vector<Symbol*>* pdynamic_symbols, | |
208 | Versions* versions); | |
dbe717ef | 209 | |
a3ad94ed | 210 | // Finish the .dynamic section and PT_DYNAMIC segment. |
dbe717ef | 211 | void |
16649710 | 212 | finish_dynamic_section(const Input_objects*, const Symbol_table*); |
dbe717ef ILT |
213 | |
214 | // Create the .interp section and PT_INTERP segment. | |
215 | void | |
216 | create_interp(const Target* target); | |
217 | ||
14b31740 ILT |
218 | // Create the version sections. |
219 | void | |
220 | create_version_sections(const Target*, const Versions*, | |
221 | unsigned int local_symcount, | |
222 | const std::vector<Symbol*>& dynamic_symbols, | |
223 | const Output_section* dynstr); | |
224 | ||
225 | template<int size, bool big_endian> | |
226 | void | |
227 | sized_create_version_sections(const Versions* versions, | |
228 | unsigned int local_symcount, | |
229 | const std::vector<Symbol*>& dynamic_symbols, | |
91da9340 ILT |
230 | const Output_section* dynstr |
231 | ACCEPT_SIZE_ENDIAN); | |
14b31740 | 232 | |
a2fb1b05 ILT |
233 | // Return whether to include this section in the link. |
234 | template<int size, bool big_endian> | |
235 | bool | |
236 | include_section(Object* object, const char* name, | |
237 | const elfcpp::Shdr<size, big_endian>&); | |
238 | ||
ead1e424 ILT |
239 | // Return the output section name to use given an input section |
240 | // name. Set *PLEN to the length of the name. *PLEN must be | |
241 | // initialized to the length of NAME. | |
242 | static const char* | |
243 | output_section_name(const char* name, size_t* plen); | |
244 | ||
a2fb1b05 | 245 | // Return the output section name to use for a linkonce section |
ead1e424 | 246 | // name. PLEN is as for output_section_name. |
a2fb1b05 | 247 | static const char* |
ead1e424 ILT |
248 | linkonce_output_name(const char* name, size_t* plen); |
249 | ||
250 | // Return the output section for NAME, TYPE and FLAGS. | |
251 | Output_section* | |
f0641a0b ILT |
252 | get_output_section(const char* name, Stringpool::Key name_key, |
253 | elfcpp::Elf_Word type, elfcpp::Elf_Xword flags); | |
a2fb1b05 ILT |
254 | |
255 | // Create a new Output_section. | |
256 | Output_section* | |
257 | make_output_section(const char* name, elfcpp::Elf_Word type, | |
258 | elfcpp::Elf_Xword flags); | |
259 | ||
dbe717ef ILT |
260 | // Set the final file offsets of all the segments. |
261 | off_t | |
262 | set_segment_offsets(const Target*, Output_segment*, unsigned int* pshndx); | |
263 | ||
14b31740 | 264 | // Set the final file offsets and section indexes of all the |
dbe717ef ILT |
265 | // sections not associated with a segment. |
266 | off_t | |
267 | set_section_offsets(off_t, unsigned int *pshndx); | |
268 | ||
a2fb1b05 ILT |
269 | // Return whether SEG1 comes before SEG2 in the output file. |
270 | static bool | |
b3168e9d | 271 | segment_precedes(const Output_segment* seg1, const Output_segment* seg2); |
a2fb1b05 ILT |
272 | |
273 | // Map from section flags to segment flags. | |
274 | static elfcpp::Elf_Word | |
275 | section_flags_to_segment(elfcpp::Elf_Xword flags); | |
276 | ||
277 | // A mapping used for group signatures. | |
278 | typedef Unordered_map<std::string, bool> Signatures; | |
279 | ||
280 | // Mapping from input section name/type/flags to output section. We | |
281 | // use canonicalized strings here. | |
282 | ||
f0641a0b | 283 | typedef std::pair<Stringpool::Key, |
a2fb1b05 ILT |
284 | std::pair<elfcpp::Elf_Word, elfcpp::Elf_Xword> > Key; |
285 | ||
286 | struct Hash_key | |
287 | { | |
288 | size_t | |
289 | operator()(const Key& k) const; | |
290 | }; | |
291 | ||
292 | typedef Unordered_map<Key, Output_section*, Hash_key> Section_name_map; | |
293 | ||
294 | // A comparison class for segments. | |
295 | ||
296 | struct Compare_segments | |
297 | { | |
298 | bool | |
299 | operator()(const Output_segment* seg1, const Output_segment* seg2) | |
300 | { return Layout::segment_precedes(seg1, seg2); } | |
301 | }; | |
302 | ||
a2fb1b05 ILT |
303 | // A reference to the options on the command line. |
304 | const General_options& options_; | |
305 | // The output section names. | |
306 | Stringpool namepool_; | |
75f65a3e ILT |
307 | // The output symbol names. |
308 | Stringpool sympool_; | |
a3ad94ed ILT |
309 | // The dynamic strings, if needed. |
310 | Stringpool dynpool_; | |
a2fb1b05 ILT |
311 | // The list of group sections and linkonce sections which we have seen. |
312 | Signatures signatures_; | |
313 | // The mapping from input section name/type/flags to output sections. | |
314 | Section_name_map section_name_map_; | |
315 | // The list of output segments. | |
316 | Segment_list segment_list_; | |
a3ad94ed ILT |
317 | // The list of output sections. |
318 | Section_list section_list_; | |
a2fb1b05 ILT |
319 | // The list of output sections which are not attached to any output |
320 | // segment. | |
a3ad94ed ILT |
321 | Section_list unattached_section_list_; |
322 | // The list of unattached Output_data objects which require special | |
323 | // handling because they are not Output_sections. | |
61ba1cf9 | 324 | Data_list special_output_list_; |
92e059d8 ILT |
325 | // A pointer to the PT_TLS segment if there is one. |
326 | Output_segment* tls_segment_; | |
a3ad94ed ILT |
327 | // The SHT_SYMTAB output section. |
328 | Output_section* symtab_section_; | |
329 | // The SHT_DYNSYM output section if there is one. | |
330 | Output_section* dynsym_section_; | |
331 | // The SHT_DYNAMIC output section if there is one. | |
332 | Output_section* dynamic_section_; | |
16649710 ILT |
333 | // The dynamic data which goes into dynamic_section_. |
334 | Output_data_dynamic* dynamic_data_; | |
61ba1cf9 ILT |
335 | }; |
336 | ||
337 | // This task handles writing out data which is not part of a section | |
338 | // or segment. | |
339 | ||
340 | class Write_data_task : public Task | |
341 | { | |
342 | public: | |
a3ad94ed ILT |
343 | Write_data_task(const Layout* layout, const Symbol_table* symtab, |
344 | const Target* target, Output_file* of, | |
61ba1cf9 | 345 | Task_token* final_blocker) |
a3ad94ed ILT |
346 | : layout_(layout), symtab_(symtab), target_(target), of_(of), |
347 | final_blocker_(final_blocker) | |
61ba1cf9 ILT |
348 | { } |
349 | ||
350 | // The standard Task methods. | |
351 | ||
352 | Is_runnable_type | |
353 | is_runnable(Workqueue*); | |
354 | ||
355 | Task_locker* | |
356 | locks(Workqueue*); | |
357 | ||
358 | void | |
359 | run(Workqueue*); | |
360 | ||
361 | private: | |
362 | const Layout* layout_; | |
a3ad94ed ILT |
363 | const Symbol_table* symtab_; |
364 | const Target* target_; | |
61ba1cf9 ILT |
365 | Output_file* of_; |
366 | Task_token* final_blocker_; | |
367 | }; | |
368 | ||
369 | // This task handles writing out the global symbols. | |
370 | ||
371 | class Write_symbols_task : public Task | |
372 | { | |
373 | public: | |
374 | Write_symbols_task(const Symbol_table* symtab, const Target* target, | |
16649710 ILT |
375 | const Stringpool* sympool, const Stringpool* dynpool, |
376 | Output_file* of, Task_token* final_blocker) | |
377 | : symtab_(symtab), target_(target), sympool_(sympool), dynpool_(dynpool), | |
378 | of_(of), final_blocker_(final_blocker) | |
61ba1cf9 ILT |
379 | { } |
380 | ||
381 | // The standard Task methods. | |
382 | ||
383 | Is_runnable_type | |
384 | is_runnable(Workqueue*); | |
385 | ||
386 | Task_locker* | |
387 | locks(Workqueue*); | |
388 | ||
389 | void | |
390 | run(Workqueue*); | |
391 | ||
392 | private: | |
393 | const Symbol_table* symtab_; | |
394 | const Target* target_; | |
395 | const Stringpool* sympool_; | |
16649710 | 396 | const Stringpool* dynpool_; |
61ba1cf9 ILT |
397 | Output_file* of_; |
398 | Task_token* final_blocker_; | |
399 | }; | |
400 | ||
92e059d8 | 401 | // This task function handles closing the file. |
61ba1cf9 | 402 | |
92e059d8 | 403 | class Close_task_runner : public Task_function_runner |
61ba1cf9 ILT |
404 | { |
405 | public: | |
92e059d8 ILT |
406 | Close_task_runner(Output_file* of) |
407 | : of_(of) | |
61ba1cf9 ILT |
408 | { } |
409 | ||
92e059d8 | 410 | // Run the operation. |
61ba1cf9 ILT |
411 | void |
412 | run(Workqueue*); | |
413 | ||
414 | private: | |
415 | Output_file* of_; | |
a2fb1b05 ILT |
416 | }; |
417 | ||
ead1e424 ILT |
418 | // A small helper function to align an address. |
419 | ||
420 | inline uint64_t | |
421 | align_address(uint64_t address, uint64_t addralign) | |
422 | { | |
423 | if (addralign != 0) | |
424 | address = (address + addralign - 1) &~ (addralign - 1); | |
425 | return address; | |
426 | } | |
427 | ||
a2fb1b05 ILT |
428 | } // End namespace gold. |
429 | ||
430 | #endif // !defined(GOLD_LAYOUT_H) |