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14bfc3f5 | 1 | // target.h -- target support for gold -*- C++ -*- |
bae7f79e | 2 | |
0e70b911 | 3 | // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. |
6cb15b7f ILT |
4 | // Written by Ian Lance Taylor <iant@google.com>. |
5 | ||
6 | // This file is part of gold. | |
7 | ||
8 | // This program is free software; you can redistribute it and/or modify | |
9 | // it under the terms of the GNU General Public License as published by | |
10 | // the Free Software Foundation; either version 3 of the License, or | |
11 | // (at your option) any later version. | |
12 | ||
13 | // This program is distributed in the hope that it will be useful, | |
14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | // GNU General Public License for more details. | |
17 | ||
18 | // You should have received a copy of the GNU General Public License | |
19 | // along with this program; if not, write to the Free Software | |
20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
21 | // MA 02110-1301, USA. | |
22 | ||
bae7f79e ILT |
23 | // The abstract class Target is the interface for target specific |
24 | // support. It defines abstract methods which each target must | |
25 | // implement. Typically there will be one target per processor, but | |
26 | // in some cases it may be necessary to have subclasses. | |
27 | ||
28 | // For speed and consistency we want to use inline functions to handle | |
29 | // relocation processing. So besides implementations of the abstract | |
30 | // methods, each target is expected to define a template | |
31 | // specialization of the relocation functions. | |
32 | ||
33 | #ifndef GOLD_TARGET_H | |
34 | #define GOLD_TARGET_H | |
35 | ||
14bfc3f5 | 36 | #include "elfcpp.h" |
8851ecca | 37 | #include "options.h" |
cd72c291 | 38 | #include "parameters.h" |
20e6d0d6 | 39 | #include "debug.h" |
14bfc3f5 | 40 | |
bae7f79e ILT |
41 | namespace gold |
42 | { | |
43 | ||
14bfc3f5 | 44 | class Object; |
364c7fa5 | 45 | class Relobj; |
61ba1cf9 | 46 | template<int size, bool big_endian> |
f6ce93d6 | 47 | class Sized_relobj; |
6a74a719 | 48 | class Relocatable_relocs; |
92e059d8 | 49 | template<int size, bool big_endian> |
730cdc88 | 50 | class Relocate_info; |
364c7fa5 | 51 | class Reloc_symbol_changes; |
f6ce93d6 ILT |
52 | class Symbol; |
53 | template<int size> | |
54 | class Sized_symbol; | |
55 | class Symbol_table; | |
730cdc88 | 56 | class Output_section; |
d5b40221 | 57 | class Input_objects; |
14bfc3f5 ILT |
58 | |
59 | // The abstract class for target specific handling. | |
60 | ||
bae7f79e ILT |
61 | class Target |
62 | { | |
63 | public: | |
14bfc3f5 ILT |
64 | virtual ~Target() |
65 | { } | |
66 | ||
21bb3914 ST |
67 | // Virtual function which is set to return true by a target if |
68 | // it can use relocation types to determine if a function's | |
69 | // pointer is taken. | |
70 | virtual bool | |
71 | can_check_for_function_pointers() const | |
72 | { return false; } | |
73 | ||
8a75a161 DK |
74 | // Whether a section called SECTION_NAME may have function pointers to |
75 | // sections not eligible for safe ICF folding. | |
76 | virtual bool | |
77 | section_may_have_icf_unsafe_pointers(const char* section_name) const | |
78 | { | |
79 | // We recognize sections for normal vtables, construction vtables and | |
80 | // EH frames. | |
81 | return (!is_prefix_of(".rodata._ZTV", section_name) | |
82 | && !is_prefix_of(".data.rel.ro._ZTV", section_name) | |
83 | && !is_prefix_of(".rodata._ZTC", section_name) | |
84 | && !is_prefix_of(".data.rel.ro._ZTC", section_name) | |
85 | && !is_prefix_of(".eh_frame", section_name)); | |
86 | } | |
87 | ||
14bfc3f5 ILT |
88 | // Return the bit size that this target implements. This should |
89 | // return 32 or 64. | |
90 | int | |
91 | get_size() const | |
75f65a3e | 92 | { return this->pti_->size; } |
14bfc3f5 ILT |
93 | |
94 | // Return whether this target is big-endian. | |
95 | bool | |
96 | is_big_endian() const | |
75f65a3e | 97 | { return this->pti_->is_big_endian; } |
14bfc3f5 | 98 | |
61ba1cf9 ILT |
99 | // Machine code to store in e_machine field of ELF header. |
100 | elfcpp::EM | |
101 | machine_code() const | |
102 | { return this->pti_->machine_code; } | |
103 | ||
d5b40221 DK |
104 | // Processor specific flags to store in e_flags field of ELF header. |
105 | elfcpp::Elf_Word | |
106 | processor_specific_flags() const | |
107 | { return this->processor_specific_flags_; } | |
108 | ||
109 | // Whether processor specific flags are set at least once. | |
110 | bool | |
111 | are_processor_specific_flags_set() const | |
112 | { return this->are_processor_specific_flags_set_; } | |
113 | ||
14bfc3f5 ILT |
114 | // Whether this target has a specific make_symbol function. |
115 | bool | |
116 | has_make_symbol() const | |
75f65a3e | 117 | { return this->pti_->has_make_symbol; } |
14bfc3f5 ILT |
118 | |
119 | // Whether this target has a specific resolve function. | |
120 | bool | |
121 | has_resolve() const | |
75f65a3e ILT |
122 | { return this->pti_->has_resolve; } |
123 | ||
c51e6221 ILT |
124 | // Whether this target has a specific code fill function. |
125 | bool | |
126 | has_code_fill() const | |
127 | { return this->pti_->has_code_fill; } | |
128 | ||
dbe717ef ILT |
129 | // Return the default name of the dynamic linker. |
130 | const char* | |
131 | dynamic_linker() const | |
132 | { return this->pti_->dynamic_linker; } | |
133 | ||
75f65a3e ILT |
134 | // Return the default address to use for the text segment. |
135 | uint64_t | |
0c5e9c22 ILT |
136 | default_text_segment_address() const |
137 | { return this->pti_->default_text_segment_address; } | |
75f65a3e ILT |
138 | |
139 | // Return the ABI specified page size. | |
140 | uint64_t | |
141 | abi_pagesize() const | |
cd72c291 | 142 | { |
8851ecca ILT |
143 | if (parameters->options().max_page_size() > 0) |
144 | return parameters->options().max_page_size(); | |
cd72c291 ILT |
145 | else |
146 | return this->pti_->abi_pagesize; | |
147 | } | |
75f65a3e ILT |
148 | |
149 | // Return the common page size used on actual systems. | |
150 | uint64_t | |
151 | common_pagesize() const | |
cd72c291 | 152 | { |
8851ecca ILT |
153 | if (parameters->options().common_page_size() > 0) |
154 | return std::min(parameters->options().common_page_size(), | |
cd72c291 ILT |
155 | this->abi_pagesize()); |
156 | else | |
157 | return std::min(this->pti_->common_pagesize, | |
158 | this->abi_pagesize()); | |
159 | } | |
14bfc3f5 | 160 | |
35cdfc9a ILT |
161 | // If we see some object files with .note.GNU-stack sections, and |
162 | // some objects files without them, this returns whether we should | |
163 | // consider the object files without them to imply that the stack | |
164 | // should be executable. | |
165 | bool | |
166 | is_default_stack_executable() const | |
167 | { return this->pti_->is_default_stack_executable; } | |
168 | ||
0864d551 ILT |
169 | // Return a character which may appear as a prefix for a wrap |
170 | // symbol. If this character appears, we strip it when checking for | |
171 | // wrapping and add it back when forming the final symbol name. | |
172 | // This should be '\0' if not special prefix is required, which is | |
173 | // the normal case. | |
174 | char | |
175 | wrap_char() const | |
176 | { return this->pti_->wrap_char; } | |
177 | ||
8a5e3e08 ILT |
178 | // Return the special section index which indicates a small common |
179 | // symbol. This will return SHN_UNDEF if there are no small common | |
180 | // symbols. | |
181 | elfcpp::Elf_Half | |
182 | small_common_shndx() const | |
183 | { return this->pti_->small_common_shndx; } | |
184 | ||
185 | // Return values to add to the section flags for the section holding | |
186 | // small common symbols. | |
187 | elfcpp::Elf_Xword | |
188 | small_common_section_flags() const | |
189 | { | |
190 | gold_assert(this->pti_->small_common_shndx != elfcpp::SHN_UNDEF); | |
191 | return this->pti_->small_common_section_flags; | |
192 | } | |
193 | ||
194 | // Return the special section index which indicates a large common | |
195 | // symbol. This will return SHN_UNDEF if there are no large common | |
196 | // symbols. | |
197 | elfcpp::Elf_Half | |
198 | large_common_shndx() const | |
199 | { return this->pti_->large_common_shndx; } | |
200 | ||
201 | // Return values to add to the section flags for the section holding | |
202 | // large common symbols. | |
203 | elfcpp::Elf_Xword | |
204 | large_common_section_flags() const | |
205 | { | |
206 | gold_assert(this->pti_->large_common_shndx != elfcpp::SHN_UNDEF); | |
207 | return this->pti_->large_common_section_flags; | |
208 | } | |
209 | ||
210 | // This hook is called when an output section is created. | |
211 | void | |
212 | new_output_section(Output_section* os) const | |
213 | { this->do_new_output_section(os); } | |
214 | ||
5a6f7e2d ILT |
215 | // This is called to tell the target to complete any sections it is |
216 | // handling. After this all sections must have their final size. | |
217 | void | |
f59f41f3 DK |
218 | finalize_sections(Layout* layout, const Input_objects* input_objects, |
219 | Symbol_table* symtab) | |
220 | { return this->do_finalize_sections(layout, input_objects, symtab); } | |
5a6f7e2d | 221 | |
ab5c9e90 ILT |
222 | // Return the value to use for a global symbol which needs a special |
223 | // value in the dynamic symbol table. This will only be called if | |
224 | // the backend first calls symbol->set_needs_dynsym_value(). | |
225 | uint64_t | |
226 | dynsym_value(const Symbol* sym) const | |
227 | { return this->do_dynsym_value(sym); } | |
228 | ||
c51e6221 ILT |
229 | // Return a string to use to fill out a code section. This is |
230 | // basically one or more NOPS which must fill out the specified | |
231 | // length in bytes. | |
232 | std::string | |
8851ecca | 233 | code_fill(section_size_type length) const |
c51e6221 ILT |
234 | { return this->do_code_fill(length); } |
235 | ||
9a2d6984 ILT |
236 | // Return whether SYM is known to be defined by the ABI. This is |
237 | // used to avoid inappropriate warnings about undefined symbols. | |
238 | bool | |
9c2d0ef9 | 239 | is_defined_by_abi(const Symbol* sym) const |
9a2d6984 ILT |
240 | { return this->do_is_defined_by_abi(sym); } |
241 | ||
36959681 ILT |
242 | // Adjust the output file header before it is written out. VIEW |
243 | // points to the header in external form. LEN is the length. | |
244 | void | |
245 | adjust_elf_header(unsigned char* view, int len) const | |
246 | { return this->do_adjust_elf_header(view, len); } | |
247 | ||
bb04269c DK |
248 | // Return whether NAME is a local label name. This is used to implement the |
249 | // --discard-locals options. | |
250 | bool | |
251 | is_local_label_name(const char* name) const | |
252 | { return this->do_is_local_label_name(name); } | |
253 | ||
e291e7b9 ILT |
254 | // Get the symbol index to use for a target specific reloc. |
255 | unsigned int | |
256 | reloc_symbol_index(void* arg, unsigned int type) const | |
257 | { return this->do_reloc_symbol_index(arg, type); } | |
258 | ||
259 | // Get the addend to use for a target specific reloc. | |
260 | uint64_t | |
261 | reloc_addend(void* arg, unsigned int type, uint64_t addend) const | |
262 | { return this->do_reloc_addend(arg, type, addend); } | |
263 | ||
b6848d3c ILT |
264 | // Return true if a reference to SYM from a reloc of type R_TYPE |
265 | // means that the current function may call an object compiled | |
266 | // without -fsplit-stack. SYM is known to be defined in an object | |
267 | // compiled without -fsplit-stack. | |
268 | bool | |
269 | is_call_to_non_split(const Symbol* sym, unsigned int r_type) const | |
270 | { return this->do_is_call_to_non_split(sym, r_type); } | |
271 | ||
364c7fa5 ILT |
272 | // A function starts at OFFSET in section SHNDX in OBJECT. That |
273 | // function was compiled with -fsplit-stack, but it refers to a | |
274 | // function which was compiled without -fsplit-stack. VIEW is a | |
275 | // modifiable view of the section; VIEW_SIZE is the size of the | |
276 | // view. The target has to adjust the function so that it allocates | |
277 | // enough stack. | |
278 | void | |
279 | calls_non_split(Relobj* object, unsigned int shndx, | |
280 | section_offset_type fnoffset, section_size_type fnsize, | |
281 | unsigned char* view, section_size_type view_size, | |
282 | std::string* from, std::string* to) const | |
283 | { | |
284 | this->do_calls_non_split(object, shndx, fnoffset, fnsize, view, view_size, | |
285 | from, to); | |
286 | } | |
287 | ||
f733487b DK |
288 | // Make an ELF object. |
289 | template<int size, bool big_endian> | |
290 | Object* | |
291 | make_elf_object(const std::string& name, Input_file* input_file, | |
292 | off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr) | |
293 | { return this->do_make_elf_object(name, input_file, offset, ehdr); } | |
294 | ||
c0a62865 DK |
295 | // Make an output section. |
296 | Output_section* | |
297 | make_output_section(const char* name, elfcpp::Elf_Word type, | |
298 | elfcpp::Elf_Xword flags) | |
299 | { return this->do_make_output_section(name, type, flags); } | |
300 | ||
20e6d0d6 DK |
301 | // Return true if target wants to perform relaxation. |
302 | bool | |
303 | may_relax() const | |
304 | { | |
305 | // Run the dummy relaxation pass twice if relaxation debugging is enabled. | |
306 | if (is_debugging_enabled(DEBUG_RELAXATION)) | |
307 | return true; | |
308 | ||
309 | return this->do_may_relax(); | |
310 | } | |
311 | ||
312 | // Perform a relaxation pass. Return true if layout may be changed. | |
313 | bool | |
c0a62865 DK |
314 | relax(int pass, const Input_objects* input_objects, Symbol_table* symtab, |
315 | Layout* layout) | |
20e6d0d6 DK |
316 | { |
317 | // Run the dummy relaxation pass twice if relaxation debugging is enabled. | |
318 | if (is_debugging_enabled(DEBUG_RELAXATION)) | |
319 | return pass < 2; | |
320 | ||
c0a62865 DK |
321 | return this->do_relax(pass, input_objects, symtab, layout); |
322 | } | |
20e6d0d6 | 323 | |
05a352e6 DK |
324 | // Return the target-specific name of attributes section. This is |
325 | // NULL if a target does not use attributes section or if it uses | |
326 | // the default section name ".gnu.attributes". | |
327 | const char* | |
328 | attributes_section() const | |
329 | { return this->pti_->attributes_section; } | |
330 | ||
331 | // Return the vendor name of vendor attributes. | |
332 | const char* | |
333 | attributes_vendor() const | |
334 | { return this->pti_->attributes_vendor; } | |
335 | ||
336 | // Whether a section called NAME is an attribute section. | |
337 | bool | |
338 | is_attributes_section(const char* name) const | |
339 | { | |
340 | return ((this->pti_->attributes_section != NULL | |
341 | && strcmp(name, this->pti_->attributes_section) == 0) | |
342 | || strcmp(name, ".gnu.attributes") == 0); | |
343 | } | |
344 | ||
345 | // Return a bit mask of argument types for attribute with TAG. | |
346 | int | |
347 | attribute_arg_type(int tag) const | |
348 | { return this->do_attribute_arg_type(tag); } | |
349 | ||
350 | // Return the attribute tag of the position NUM in the list of fixed | |
351 | // attributes. Normally there is no reordering and | |
352 | // attributes_order(NUM) == NUM. | |
353 | int | |
354 | attributes_order(int num) const | |
355 | { return this->do_attributes_order(num); } | |
356 | ||
0d31c79d DK |
357 | // When a target is selected as the default target, we call this method, |
358 | // which may be used for expensive, target-specific initialization. | |
359 | void | |
360 | select_as_default_target() | |
361 | { this->do_select_as_default_target(); } | |
362 | ||
14bfc3f5 | 363 | protected: |
75f65a3e ILT |
364 | // This struct holds the constant information for a child class. We |
365 | // use a struct to avoid the overhead of virtual function calls for | |
366 | // simple information. | |
367 | struct Target_info | |
368 | { | |
369 | // Address size (32 or 64). | |
370 | int size; | |
371 | // Whether the target is big endian. | |
372 | bool is_big_endian; | |
61ba1cf9 ILT |
373 | // The code to store in the e_machine field of the ELF header. |
374 | elfcpp::EM machine_code; | |
75f65a3e ILT |
375 | // Whether this target has a specific make_symbol function. |
376 | bool has_make_symbol; | |
377 | // Whether this target has a specific resolve function. | |
378 | bool has_resolve; | |
c51e6221 ILT |
379 | // Whether this target has a specific code fill function. |
380 | bool has_code_fill; | |
35cdfc9a ILT |
381 | // Whether an object file with no .note.GNU-stack sections implies |
382 | // that the stack should be executable. | |
383 | bool is_default_stack_executable; | |
0864d551 ILT |
384 | // Prefix character to strip when checking for wrapping. |
385 | char wrap_char; | |
dbe717ef ILT |
386 | // The default dynamic linker name. |
387 | const char* dynamic_linker; | |
75f65a3e | 388 | // The default text segment address. |
0c5e9c22 | 389 | uint64_t default_text_segment_address; |
75f65a3e ILT |
390 | // The ABI specified page size. |
391 | uint64_t abi_pagesize; | |
392 | // The common page size used by actual implementations. | |
393 | uint64_t common_pagesize; | |
8a5e3e08 ILT |
394 | // The special section index for small common symbols; SHN_UNDEF |
395 | // if none. | |
396 | elfcpp::Elf_Half small_common_shndx; | |
397 | // The special section index for large common symbols; SHN_UNDEF | |
398 | // if none. | |
399 | elfcpp::Elf_Half large_common_shndx; | |
400 | // Section flags for small common section. | |
401 | elfcpp::Elf_Xword small_common_section_flags; | |
402 | // Section flags for large common section. | |
403 | elfcpp::Elf_Xword large_common_section_flags; | |
05a352e6 DK |
404 | // Name of attributes section if it is not ".gnu.attributes". |
405 | const char* attributes_section; | |
406 | // Vendor name of vendor attributes. | |
407 | const char* attributes_vendor; | |
75f65a3e ILT |
408 | }; |
409 | ||
410 | Target(const Target_info* pti) | |
d5b40221 DK |
411 | : pti_(pti), processor_specific_flags_(0), |
412 | are_processor_specific_flags_set_(false) | |
14bfc3f5 ILT |
413 | { } |
414 | ||
8a5e3e08 ILT |
415 | // Virtual function which may be implemented by the child class. |
416 | virtual void | |
417 | do_new_output_section(Output_section*) const | |
418 | { } | |
419 | ||
5a6f7e2d ILT |
420 | // Virtual function which may be implemented by the child class. |
421 | virtual void | |
f59f41f3 | 422 | do_finalize_sections(Layout*, const Input_objects*, Symbol_table*) |
5a6f7e2d ILT |
423 | { } |
424 | ||
ab5c9e90 ILT |
425 | // Virtual function which may be implemented by the child class. |
426 | virtual uint64_t | |
427 | do_dynsym_value(const Symbol*) const | |
428 | { gold_unreachable(); } | |
429 | ||
c51e6221 ILT |
430 | // Virtual function which must be implemented by the child class if |
431 | // needed. | |
432 | virtual std::string | |
8851ecca | 433 | do_code_fill(section_size_type) const |
c51e6221 ILT |
434 | { gold_unreachable(); } |
435 | ||
9a2d6984 ILT |
436 | // Virtual function which may be implemented by the child class. |
437 | virtual bool | |
9c2d0ef9 | 438 | do_is_defined_by_abi(const Symbol*) const |
9a2d6984 ILT |
439 | { return false; } |
440 | ||
36959681 ILT |
441 | // Adjust the output file header before it is written out. VIEW |
442 | // points to the header in external form. LEN is the length, and | |
443 | // will be one of the values of elfcpp::Elf_sizes<size>::ehdr_size. | |
444 | // By default, we do nothing. | |
445 | virtual void | |
446 | do_adjust_elf_header(unsigned char*, int) const | |
447 | { } | |
448 | ||
bb04269c DK |
449 | // Virtual function which may be overriden by the child class. |
450 | virtual bool | |
451 | do_is_local_label_name(const char*) const; | |
452 | ||
e291e7b9 ILT |
453 | // Virtual function that must be overridden by a target which uses |
454 | // target specific relocations. | |
455 | virtual unsigned int | |
456 | do_reloc_symbol_index(void*, unsigned int) const | |
457 | { gold_unreachable(); } | |
458 | ||
459 | // Virtual function that must be overidden by a target which uses | |
460 | // target specific relocations. | |
461 | virtual uint64_t | |
462 | do_reloc_addend(void*, unsigned int, uint64_t) const | |
463 | { gold_unreachable(); } | |
464 | ||
b6848d3c ILT |
465 | // Virtual function which may be overridden by the child class. The |
466 | // default implementation is that any function not defined by the | |
467 | // ABI is a call to a non-split function. | |
468 | virtual bool | |
469 | do_is_call_to_non_split(const Symbol* sym, unsigned int) const; | |
470 | ||
364c7fa5 ILT |
471 | // Virtual function which may be overridden by the child class. |
472 | virtual void | |
473 | do_calls_non_split(Relobj* object, unsigned int, section_offset_type, | |
474 | section_size_type, unsigned char*, section_size_type, | |
475 | std::string*, std::string*) const; | |
476 | ||
f733487b | 477 | // make_elf_object hooks. There are four versions of these for |
7296d933 | 478 | // different address sizes and endianness. |
364c7fa5 | 479 | |
d5b40221 DK |
480 | // Set processor specific flags. |
481 | void | |
482 | set_processor_specific_flags(elfcpp::Elf_Word flags) | |
483 | { | |
484 | this->processor_specific_flags_ = flags; | |
485 | this->are_processor_specific_flags_set_ = true; | |
486 | } | |
487 | ||
f733487b DK |
488 | #ifdef HAVE_TARGET_32_LITTLE |
489 | // Virtual functions which may be overriden by the child class. | |
490 | virtual Object* | |
491 | do_make_elf_object(const std::string&, Input_file*, off_t, | |
492 | const elfcpp::Ehdr<32, false>&); | |
493 | #endif | |
494 | ||
495 | #ifdef HAVE_TARGET_32_BIG | |
496 | // Virtual functions which may be overriden by the child class. | |
497 | virtual Object* | |
498 | do_make_elf_object(const std::string&, Input_file*, off_t, | |
499 | const elfcpp::Ehdr<32, true>&); | |
500 | #endif | |
501 | ||
502 | #ifdef HAVE_TARGET_64_LITTLE | |
503 | // Virtual functions which may be overriden by the child class. | |
504 | virtual Object* | |
505 | do_make_elf_object(const std::string&, Input_file*, off_t, | |
506 | const elfcpp::Ehdr<64, false>& ehdr); | |
507 | #endif | |
508 | ||
509 | #ifdef HAVE_TARGET_64_BIG | |
510 | // Virtual functions which may be overriden by the child class. | |
511 | virtual Object* | |
512 | do_make_elf_object(const std::string& name, Input_file* input_file, | |
513 | off_t offset, const elfcpp::Ehdr<64, true>& ehdr); | |
514 | #endif | |
515 | ||
c0a62865 DK |
516 | // Virtual functions which may be overriden by the child class. |
517 | virtual Output_section* | |
518 | do_make_output_section(const char* name, elfcpp::Elf_Word type, | |
519 | elfcpp::Elf_Xword flags); | |
520 | ||
20e6d0d6 DK |
521 | // Virtual function which may be overriden by the child class. |
522 | virtual bool | |
523 | do_may_relax() const | |
524 | { return parameters->options().relax(); } | |
525 | ||
526 | // Virtual function which may be overriden by the child class. | |
527 | virtual bool | |
c0a62865 | 528 | do_relax(int, const Input_objects*, Symbol_table*, Layout*) |
20e6d0d6 DK |
529 | { return false; } |
530 | ||
364c7fa5 ILT |
531 | // A function for targets to call. Return whether BYTES/LEN matches |
532 | // VIEW/VIEW_SIZE at OFFSET. | |
533 | bool | |
534 | match_view(const unsigned char* view, section_size_type view_size, | |
535 | section_offset_type offset, const char* bytes, size_t len) const; | |
536 | ||
537 | // Set the contents of a VIEW/VIEW_SIZE to nops starting at OFFSET | |
538 | // for LEN bytes. | |
539 | void | |
540 | set_view_to_nop(unsigned char* view, section_size_type view_size, | |
541 | section_offset_type offset, size_t len) const; | |
542 | ||
05a352e6 DK |
543 | // This must be overriden by the child class if it has target-specific |
544 | // attributes subsection in the attribute section. | |
545 | virtual int | |
546 | do_attribute_arg_type(int) const | |
547 | { gold_unreachable(); } | |
548 | ||
549 | // This may be overridden by the child class. | |
550 | virtual int | |
551 | do_attributes_order(int num) const | |
552 | { return num; } | |
553 | ||
0d31c79d DK |
554 | // This may be overridden by the child class. |
555 | virtual void | |
556 | do_select_as_default_target() | |
557 | { } | |
558 | ||
14bfc3f5 | 559 | private: |
f733487b | 560 | // The implementations of the four do_make_elf_object virtual functions are |
7296d933 | 561 | // almost identical except for their sizes and endianness. We use a template. |
f733487b DK |
562 | // for their implementations. |
563 | template<int size, bool big_endian> | |
564 | inline Object* | |
565 | do_make_elf_object_implementation(const std::string&, Input_file*, off_t, | |
566 | const elfcpp::Ehdr<size, big_endian>&); | |
567 | ||
14bfc3f5 ILT |
568 | Target(const Target&); |
569 | Target& operator=(const Target&); | |
570 | ||
75f65a3e ILT |
571 | // The target information. |
572 | const Target_info* pti_; | |
d5b40221 DK |
573 | // Processor-specific flags. |
574 | elfcpp::Elf_Word processor_specific_flags_; | |
575 | // Whether the processor-specific flags are set at least once. | |
576 | bool are_processor_specific_flags_set_; | |
bae7f79e ILT |
577 | }; |
578 | ||
14bfc3f5 ILT |
579 | // The abstract class for a specific size and endianness of target. |
580 | // Each actual target implementation class should derive from an | |
581 | // instantiation of Sized_target. | |
582 | ||
583 | template<int size, bool big_endian> | |
584 | class Sized_target : public Target | |
585 | { | |
586 | public: | |
587 | // Make a new symbol table entry for the target. This should be | |
588 | // overridden by a target which needs additional information in the | |
589 | // symbol table. This will only be called if has_make_symbol() | |
590 | // returns true. | |
591 | virtual Sized_symbol<size>* | |
14b31740 | 592 | make_symbol() const |
a3ad94ed | 593 | { gold_unreachable(); } |
14bfc3f5 ILT |
594 | |
595 | // Resolve a symbol for the target. This should be overridden by a | |
596 | // target which needs to take special action. TO is the | |
597 | // pre-existing symbol. SYM is the new symbol, seen in OBJECT. | |
14b31740 ILT |
598 | // VERSION is the version of SYM. This will only be called if |
599 | // has_resolve() returns true. | |
14bfc3f5 | 600 | virtual void |
14b31740 ILT |
601 | resolve(Symbol*, const elfcpp::Sym<size, big_endian>&, Object*, |
602 | const char*) | |
a3ad94ed | 603 | { gold_unreachable(); } |
14bfc3f5 | 604 | |
6d03d481 ST |
605 | // Process the relocs for a section, and record information of the |
606 | // mapping from source to destination sections. This mapping is later | |
607 | // used to determine unreferenced garbage sections. This procedure is | |
608 | // only called during garbage collection. | |
609 | virtual void | |
ad0f2072 ILT |
610 | gc_process_relocs(Symbol_table* symtab, |
611 | Layout* layout, | |
612 | Sized_relobj<size, big_endian>* object, | |
613 | unsigned int data_shndx, | |
614 | unsigned int sh_type, | |
615 | const unsigned char* prelocs, | |
616 | size_t reloc_count, | |
617 | Output_section* output_section, | |
618 | bool needs_special_offset_handling, | |
619 | size_t local_symbol_count, | |
620 | const unsigned char* plocal_symbols) = 0; | |
6d03d481 | 621 | |
92e059d8 | 622 | // Scan the relocs for a section, and record any information |
ad0f2072 ILT |
623 | // required for the symbol. SYMTAB is the symbol table. OBJECT is |
624 | // the object in which the section appears. DATA_SHNDX is the | |
625 | // section index that these relocs apply to. SH_TYPE is the type of | |
626 | // the relocation section, SHT_REL or SHT_RELA. PRELOCS points to | |
627 | // the relocation data. RELOC_COUNT is the number of relocs. | |
628 | // LOCAL_SYMBOL_COUNT is the number of local symbols. | |
629 | // OUTPUT_SECTION is the output section. | |
730cdc88 ILT |
630 | // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets to the output |
631 | // sections are not mapped as usual. PLOCAL_SYMBOLS points to the | |
632 | // local symbol data from OBJECT. GLOBAL_SYMBOLS is the array of | |
633 | // pointers to the global symbol table from OBJECT. | |
61ba1cf9 | 634 | virtual void |
ad0f2072 | 635 | scan_relocs(Symbol_table* symtab, |
ead1e424 | 636 | Layout* layout, |
f6ce93d6 | 637 | Sized_relobj<size, big_endian>* object, |
a3ad94ed | 638 | unsigned int data_shndx, |
92e059d8 ILT |
639 | unsigned int sh_type, |
640 | const unsigned char* prelocs, | |
641 | size_t reloc_count, | |
730cdc88 ILT |
642 | Output_section* output_section, |
643 | bool needs_special_offset_handling, | |
92e059d8 | 644 | size_t local_symbol_count, |
730cdc88 | 645 | const unsigned char* plocal_symbols) = 0; |
92e059d8 ILT |
646 | |
647 | // Relocate section data. SH_TYPE is the type of the relocation | |
648 | // section, SHT_REL or SHT_RELA. PRELOCS points to the relocation | |
730cdc88 ILT |
649 | // information. RELOC_COUNT is the number of relocs. |
650 | // OUTPUT_SECTION is the output section. | |
651 | // NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets must be mapped | |
652 | // to correspond to the output section. VIEW is a view into the | |
653 | // output file holding the section contents, VIEW_ADDRESS is the | |
654 | // virtual address of the view, and VIEW_SIZE is the size of the | |
655 | // view. If NEEDS_SPECIAL_OFFSET_HANDLING is true, the VIEW_xx | |
656 | // parameters refer to the complete output section data, not just | |
657 | // the input section data. | |
92e059d8 ILT |
658 | virtual void |
659 | relocate_section(const Relocate_info<size, big_endian>*, | |
660 | unsigned int sh_type, | |
661 | const unsigned char* prelocs, | |
662 | size_t reloc_count, | |
730cdc88 ILT |
663 | Output_section* output_section, |
664 | bool needs_special_offset_handling, | |
92e059d8 ILT |
665 | unsigned char* view, |
666 | typename elfcpp::Elf_types<size>::Elf_Addr view_address, | |
364c7fa5 ILT |
667 | section_size_type view_size, |
668 | const Reloc_symbol_changes*) = 0; | |
61ba1cf9 | 669 | |
6a74a719 ILT |
670 | // Scan the relocs during a relocatable link. The parameters are |
671 | // like scan_relocs, with an additional Relocatable_relocs | |
672 | // parameter, used to record the disposition of the relocs. | |
673 | virtual void | |
ad0f2072 | 674 | scan_relocatable_relocs(Symbol_table* symtab, |
6a74a719 ILT |
675 | Layout* layout, |
676 | Sized_relobj<size, big_endian>* object, | |
677 | unsigned int data_shndx, | |
678 | unsigned int sh_type, | |
679 | const unsigned char* prelocs, | |
680 | size_t reloc_count, | |
681 | Output_section* output_section, | |
682 | bool needs_special_offset_handling, | |
683 | size_t local_symbol_count, | |
684 | const unsigned char* plocal_symbols, | |
685 | Relocatable_relocs*) = 0; | |
686 | ||
687 | // Relocate a section during a relocatable link. The parameters are | |
688 | // like relocate_section, with additional parameters for the view of | |
689 | // the output reloc section. | |
690 | virtual void | |
691 | relocate_for_relocatable(const Relocate_info<size, big_endian>*, | |
692 | unsigned int sh_type, | |
693 | const unsigned char* prelocs, | |
694 | size_t reloc_count, | |
695 | Output_section* output_section, | |
696 | off_t offset_in_output_section, | |
697 | const Relocatable_relocs*, | |
698 | unsigned char* view, | |
699 | typename elfcpp::Elf_types<size>::Elf_Addr | |
700 | view_address, | |
701 | section_size_type view_size, | |
702 | unsigned char* reloc_view, | |
703 | section_size_type reloc_view_size) = 0; | |
5c388529 DK |
704 | |
705 | // Perform target-specific processing in a relocatable link. This is | |
706 | // only used if we use the relocation strategy RELOC_SPECIAL. | |
707 | // RELINFO points to a Relocation_info structure. SH_TYPE is the relocation | |
708 | // section type. PRELOC_IN points to the original relocation. RELNUM is | |
709 | // the index number of the relocation in the relocation section. | |
710 | // OUTPUT_SECTION is the output section to which the relocation is applied. | |
711 | // OFFSET_IN_OUTPUT_SECTION is the offset of the relocation input section | |
712 | // within the output section. VIEW points to the output view of the | |
713 | // output section. VIEW_ADDRESS is output address of the view. VIEW_SIZE | |
714 | // is the size of the output view and PRELOC_OUT points to the new | |
715 | // relocation in the output object. | |
716 | // | |
717 | // A target only needs to override this if the generic code in | |
718 | // target-reloc.h cannot handle some relocation types. | |
6a74a719 | 719 | |
5c388529 DK |
720 | virtual void |
721 | relocate_special_relocatable(const Relocate_info<size, big_endian>* | |
722 | /*relinfo */, | |
723 | unsigned int /* sh_type */, | |
724 | const unsigned char* /* preloc_in */, | |
725 | size_t /* relnum */, | |
726 | Output_section* /* output_section */, | |
727 | off_t /* offset_in_output_section */, | |
728 | unsigned char* /* view */, | |
729 | typename elfcpp::Elf_types<size>::Elf_Addr | |
730 | /* view_address */, | |
731 | section_size_type /* view_size */, | |
732 | unsigned char* /* preloc_out*/) | |
733 | { gold_unreachable(); } | |
734 | ||
0e70b911 CC |
735 | // Return the number of entries in the GOT. This is only used for |
736 | // laying out the incremental link info sections. A target needs | |
737 | // to implement this to support incremental linking. | |
738 | ||
739 | virtual unsigned int | |
740 | got_entry_count() const | |
741 | { gold_unreachable(); } | |
742 | ||
743 | // Return the number of entries in the PLT. This is only used for | |
744 | // laying out the incremental link info sections. A target needs | |
745 | // to implement this to support incremental linking. | |
746 | ||
747 | virtual unsigned int | |
748 | plt_entry_count() const | |
749 | { gold_unreachable(); } | |
750 | ||
751 | // Return the offset of the first non-reserved PLT entry. This is | |
752 | // only used for laying out the incremental link info sections. | |
753 | // A target needs to implement this to support incremental linking. | |
754 | ||
755 | virtual unsigned int | |
756 | first_plt_entry_offset() const | |
757 | { gold_unreachable(); } | |
758 | ||
759 | // Return the size of each PLT entry. This is only used for | |
760 | // laying out the incremental link info sections. A target needs | |
761 | // to implement this to support incremental linking. | |
762 | ||
763 | virtual unsigned int | |
764 | plt_entry_size() const | |
765 | { gold_unreachable(); } | |
766 | ||
14bfc3f5 | 767 | protected: |
75f65a3e ILT |
768 | Sized_target(const Target::Target_info* pti) |
769 | : Target(pti) | |
770 | { | |
a3ad94ed ILT |
771 | gold_assert(pti->size == size); |
772 | gold_assert(pti->is_big_endian ? big_endian : !big_endian); | |
75f65a3e | 773 | } |
14bfc3f5 | 774 | }; |
bae7f79e ILT |
775 | |
776 | } // End namespace gold. | |
777 | ||
778 | #endif // !defined(GOLD_TARGET_H) |