1 /*===-- llvm-c/lto.h - LTO Public C Interface ---------------------*- C -*-===*\
2 |*                                                                            *|
3 |*                     The LLVM Compiler Infrastructure                       *|
4 |*                                                                            *|
5 |* This file is distributed under the University of Illinois Open Source      *|
6 |* License. See LICENSE.TXT for details.                                      *|
7 |*                                                                            *|
8 |*===----------------------------------------------------------------------===*|
9 |*                                                                            *|
10 |* This header provides public interface to an abstract link time optimization*|
11 |* library.  LLVM provides an implementation of this interface for use with   *|
12 |* llvm bitcode files.                                                        *|
13 |*                                                                            *|
14 \*===----------------------------------------------------------------------===*/
15 
16 #ifndef LLVM_C_LTO_H
17 #define LLVM_C_LTO_H
18 
19 #include <stddef.h>
20 #include <sys/types.h>
21 
22 #ifndef __cplusplus
23 #if !defined(_MSC_VER)
24 #include <stdbool.h>
25 typedef bool lto_bool_t;
26 #else
27 /* MSVC in particular does not have anything like _Bool or bool in C, but we can
28    at least make sure the type is the same size.  The implementation side will
29    use C++ bool. */
30 typedef unsigned char lto_bool_t;
31 #endif
32 #else
33 typedef bool lto_bool_t;
34 #endif
35 
36 /**
37  * @defgroup LLVMCLTO LTO
38  * @ingroup LLVMC
39  *
40  * @{
41  */
42 
43 #define LTO_API_VERSION 13
44 
45 /**
46  * \since prior to LTO_API_VERSION=3
47  */
48 typedef enum {
49     LTO_SYMBOL_ALIGNMENT_MASK              = 0x0000001F, /* log2 of alignment */
50     LTO_SYMBOL_PERMISSIONS_MASK            = 0x000000E0,
51     LTO_SYMBOL_PERMISSIONS_CODE            = 0x000000A0,
52     LTO_SYMBOL_PERMISSIONS_DATA            = 0x000000C0,
53     LTO_SYMBOL_PERMISSIONS_RODATA          = 0x00000080,
54     LTO_SYMBOL_DEFINITION_MASK             = 0x00000700,
55     LTO_SYMBOL_DEFINITION_REGULAR          = 0x00000100,
56     LTO_SYMBOL_DEFINITION_TENTATIVE        = 0x00000200,
57     LTO_SYMBOL_DEFINITION_WEAK             = 0x00000300,
58     LTO_SYMBOL_DEFINITION_UNDEFINED        = 0x00000400,
59     LTO_SYMBOL_DEFINITION_WEAKUNDEF        = 0x00000500,
60     LTO_SYMBOL_SCOPE_MASK                  = 0x00003800,
61     LTO_SYMBOL_SCOPE_INTERNAL              = 0x00000800,
62     LTO_SYMBOL_SCOPE_HIDDEN                = 0x00001000,
63     LTO_SYMBOL_SCOPE_PROTECTED             = 0x00002000,
64     LTO_SYMBOL_SCOPE_DEFAULT               = 0x00001800,
65     LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN = 0x00002800
66 } lto_symbol_attributes;
67 
68 /**
69  * \since prior to LTO_API_VERSION=3
70  */
71 typedef enum {
72     LTO_DEBUG_MODEL_NONE         = 0,
73     LTO_DEBUG_MODEL_DWARF        = 1
74 } lto_debug_model;
75 
76 /**
77  * \since prior to LTO_API_VERSION=3
78  */
79 typedef enum {
80     LTO_CODEGEN_PIC_MODEL_STATIC         = 0,
81     LTO_CODEGEN_PIC_MODEL_DYNAMIC        = 1,
82     LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC = 2,
83     LTO_CODEGEN_PIC_MODEL_DEFAULT        = 3
84 } lto_codegen_model;
85 
86 /** opaque reference to a loaded object module */
87 typedef struct LLVMOpaqueLTOModule *lto_module_t;
88 
89 /** opaque reference to a code generator */
90 typedef struct LLVMOpaqueLTOCodeGenerator *lto_code_gen_t;
91 
92 #ifdef __cplusplus
93 extern "C" {
94 #endif
95 
96 /**
97  * Returns a printable string.
98  *
99  * \since prior to LTO_API_VERSION=3
100  */
101 extern const char*
102 lto_get_version(void);
103 
104 
105 /**
106  * Returns the last error string or NULL if last operation was successful.
107  *
108  * \since prior to LTO_API_VERSION=3
109  */
110 extern const char*
111 lto_get_error_message(void);
112 
113 /**
114  * Checks if a file is a loadable object file.
115  *
116  * \since prior to LTO_API_VERSION=3
117  */
118 extern lto_bool_t
119 lto_module_is_object_file(const char* path);
120 
121 
122 /**
123  * Checks if a file is a loadable object compiled for requested target.
124  *
125  * \since prior to LTO_API_VERSION=3
126  */
127 extern lto_bool_t
128 lto_module_is_object_file_for_target(const char* path,
129                                      const char* target_triple_prefix);
130 
131 
132 /**
133  * Checks if a buffer is a loadable object file.
134  *
135  * \since prior to LTO_API_VERSION=3
136  */
137 extern lto_bool_t
138 lto_module_is_object_file_in_memory(const void* mem, size_t length);
139 
140 
141 /**
142  * Checks if a buffer is a loadable object compiled for requested target.
143  *
144  * \since prior to LTO_API_VERSION=3
145  */
146 extern lto_bool_t
147 lto_module_is_object_file_in_memory_for_target(const void* mem, size_t length,
148                                               const char* target_triple_prefix);
149 
150 
151 /**
152  * Loads an object file from disk.
153  * Returns NULL on error (check lto_get_error_message() for details).
154  *
155  * \since prior to LTO_API_VERSION=3
156  */
157 extern lto_module_t
158 lto_module_create(const char* path);
159 
160 
161 /**
162  * Loads an object file from memory.
163  * Returns NULL on error (check lto_get_error_message() for details).
164  *
165  * \since prior to LTO_API_VERSION=3
166  */
167 extern lto_module_t
168 lto_module_create_from_memory(const void* mem, size_t length);
169 
170 /**
171  * Loads an object file from memory with an extra path argument.
172  * Returns NULL on error (check lto_get_error_message() for details).
173  *
174  * \since prior to LTO_API_VERSION=9
175  */
176 extern lto_module_t
177 lto_module_create_from_memory_with_path(const void* mem, size_t length,
178                                         const char *path);
179 
180 /**
181  * \brief Loads an object file in its own context.
182  *
183  * Loads an object file in its own LLVMContext.  This function call is
184  * thread-safe.  However, modules created this way should not be merged into an
185  * lto_code_gen_t using \a lto_codegen_add_module().
186  *
187  * Returns NULL on error (check lto_get_error_message() for details).
188  *
189  * \since LTO_API_VERSION=11
190  */
191 extern lto_module_t
192 lto_module_create_in_local_context(const void *mem, size_t length,
193                                    const char *path);
194 
195 /**
196  * \brief Loads an object file in the codegen context.
197  *
198  * Loads an object file into the same context as \c cg.  The module is safe to
199  * add using \a lto_codegen_add_module().
200  *
201  * Returns NULL on error (check lto_get_error_message() for details).
202  *
203  * \since LTO_API_VERSION=11
204  */
205 extern lto_module_t
206 lto_module_create_in_codegen_context(const void *mem, size_t length,
207                                      const char *path, lto_code_gen_t cg);
208 
209 /**
210  * Loads an object file from disk. The seek point of fd is not preserved.
211  * Returns NULL on error (check lto_get_error_message() for details).
212  *
213  * \since LTO_API_VERSION=5
214  */
215 extern lto_module_t
216 lto_module_create_from_fd(int fd, const char *path, size_t file_size);
217 
218 /**
219  * Loads an object file from disk. The seek point of fd is not preserved.
220  * Returns NULL on error (check lto_get_error_message() for details).
221  *
222  * \since LTO_API_VERSION=5
223  */
224 extern lto_module_t
225 lto_module_create_from_fd_at_offset(int fd, const char *path, size_t file_size,
226                                     size_t map_size, off_t offset);
227 
228 /**
229  * Frees all memory internally allocated by the module.
230  * Upon return the lto_module_t is no longer valid.
231  *
232  * \since prior to LTO_API_VERSION=3
233  */
234 extern void
235 lto_module_dispose(lto_module_t mod);
236 
237 /**
238  * Returns triple string which the object module was compiled under.
239  *
240  * \since prior to LTO_API_VERSION=3
241  */
242 extern const char*
243 lto_module_get_target_triple(lto_module_t mod);
244 
245 /**
246  * Sets triple string with which the object will be codegened.
247  *
248  * \since LTO_API_VERSION=4
249  */
250 extern void
251 lto_module_set_target_triple(lto_module_t mod, const char *triple);
252 
253 
254 /**
255  * Returns the number of symbols in the object module.
256  *
257  * \since prior to LTO_API_VERSION=3
258  */
259 extern unsigned int
260 lto_module_get_num_symbols(lto_module_t mod);
261 
262 
263 /**
264  * Returns the name of the ith symbol in the object module.
265  *
266  * \since prior to LTO_API_VERSION=3
267  */
268 extern const char*
269 lto_module_get_symbol_name(lto_module_t mod, unsigned int index);
270 
271 
272 /**
273  * Returns the attributes of the ith symbol in the object module.
274  *
275  * \since prior to LTO_API_VERSION=3
276  */
277 extern lto_symbol_attributes
278 lto_module_get_symbol_attribute(lto_module_t mod, unsigned int index);
279 
280 
281 /**
282  * Returns the number of dependent libraries in the object module.
283  *
284  * \since LTO_API_VERSION=8
285  */
286 extern unsigned int
287 lto_module_get_num_deplibs(lto_module_t mod);
288 
289 
290 /**
291  * Returns the ith dependent library in the module.
292  *
293  * \since LTO_API_VERSION=8
294  */
295 extern const char*
296 lto_module_get_deplib(lto_module_t mod, unsigned int index);
297 
298 
299 /**
300  * Returns the number of linker options in the object module.
301  *
302  * \since LTO_API_VERSION=8
303  */
304 extern unsigned int
305 lto_module_get_num_linkeropts(lto_module_t mod);
306 
307 
308 /**
309  * Returns the ith linker option in the module.
310  *
311  * \since LTO_API_VERSION=8
312  */
313 extern const char*
314 lto_module_get_linkeropt(lto_module_t mod, unsigned int index);
315 
316 
317 /**
318  * Diagnostic severity.
319  *
320  * \since LTO_API_VERSION=7
321  */
322 typedef enum {
323   LTO_DS_ERROR = 0,
324   LTO_DS_WARNING = 1,
325   LTO_DS_REMARK = 3, // Added in LTO_API_VERSION=10.
326   LTO_DS_NOTE = 2
327 } lto_codegen_diagnostic_severity_t;
328 
329 /**
330  * Diagnostic handler type.
331  * \p severity defines the severity.
332  * \p diag is the actual diagnostic.
333  * The diagnostic is not prefixed by any of severity keyword, e.g., 'error: '.
334  * \p ctxt is used to pass the context set with the diagnostic handler.
335  *
336  * \since LTO_API_VERSION=7
337  */
338 typedef void (*lto_diagnostic_handler_t)(
339     lto_codegen_diagnostic_severity_t severity, const char *diag, void *ctxt);
340 
341 /**
342  * Set a diagnostic handler and the related context (void *).
343  * This is more general than lto_get_error_message, as the diagnostic handler
344  * can be called at anytime within lto.
345  *
346  * \since LTO_API_VERSION=7
347  */
348 extern void lto_codegen_set_diagnostic_handler(lto_code_gen_t,
349                                                lto_diagnostic_handler_t,
350                                                void *);
351 
352 /**
353  * Instantiates a code generator.
354  * Returns NULL on error (check lto_get_error_message() for details).
355  *
356  * All modules added using \a lto_codegen_add_module() must have been created
357  * in the same context as the codegen.
358  *
359  * \since prior to LTO_API_VERSION=3
360  */
361 extern lto_code_gen_t
362 lto_codegen_create(void);
363 
364 /**
365  * \brief Instantiate a code generator in its own context.
366  *
367  * Instantiates a code generator in its own context.  Modules added via \a
368  * lto_codegen_add_module() must have all been created in the same context,
369  * using \a lto_module_create_in_codegen_context().
370  *
371  * \since LTO_API_VERSION=11
372  */
373 extern lto_code_gen_t
374 lto_codegen_create_in_local_context(void);
375 
376 /**
377  * Frees all code generator and all memory it internally allocated.
378  * Upon return the lto_code_gen_t is no longer valid.
379  *
380  * \since prior to LTO_API_VERSION=3
381  */
382 extern void
383 lto_codegen_dispose(lto_code_gen_t);
384 
385 /**
386  * Add an object module to the set of modules for which code will be generated.
387  * Returns true on error (check lto_get_error_message() for details).
388  *
389  * \c cg and \c mod must both be in the same context.  See \a
390  * lto_codegen_create_in_local_context() and \a
391  * lto_module_create_in_codegen_context().
392  *
393  * \since prior to LTO_API_VERSION=3
394  */
395 extern lto_bool_t
396 lto_codegen_add_module(lto_code_gen_t cg, lto_module_t mod);
397 
398 /**
399  * Sets the object module for code generation. This will transfer the ownship of
400  * the module to code generator.
401  *
402  * \c cg and \c mod must both be in the same context.
403  *
404  * \since prior to LTO_API_VERSION=13
405  */
406 extern void
407 lto_codegen_set_module(lto_code_gen_t cg, lto_module_t mod);
408 
409 /**
410  * Sets if debug info should be generated.
411  * Returns true on error (check lto_get_error_message() for details).
412  *
413  * \since prior to LTO_API_VERSION=3
414  */
415 extern lto_bool_t
416 lto_codegen_set_debug_model(lto_code_gen_t cg, lto_debug_model);
417 
418 
419 /**
420  * Sets which PIC code model to generated.
421  * Returns true on error (check lto_get_error_message() for details).
422  *
423  * \since prior to LTO_API_VERSION=3
424  */
425 extern lto_bool_t
426 lto_codegen_set_pic_model(lto_code_gen_t cg, lto_codegen_model);
427 
428 
429 /**
430  * Sets the cpu to generate code for.
431  *
432  * \since LTO_API_VERSION=4
433  */
434 extern void
435 lto_codegen_set_cpu(lto_code_gen_t cg, const char *cpu);
436 
437 
438 /**
439  * Sets the location of the assembler tool to run. If not set, libLTO
440  * will use gcc to invoke the assembler.
441  *
442  * \since LTO_API_VERSION=3
443  */
444 extern void
445 lto_codegen_set_assembler_path(lto_code_gen_t cg, const char* path);
446 
447 /**
448  * Sets extra arguments that libLTO should pass to the assembler.
449  *
450  * \since LTO_API_VERSION=4
451  */
452 extern void
453 lto_codegen_set_assembler_args(lto_code_gen_t cg, const char **args,
454                                int nargs);
455 
456 /**
457  * Adds to a list of all global symbols that must exist in the final generated
458  * code. If a function is not listed there, it might be inlined into every usage
459  * and optimized away.
460  *
461  * \since prior to LTO_API_VERSION=3
462  */
463 extern void
464 lto_codegen_add_must_preserve_symbol(lto_code_gen_t cg, const char* symbol);
465 
466 /**
467  * Writes a new object file at the specified path that contains the
468  * merged contents of all modules added so far.
469  * Returns true on error (check lto_get_error_message() for details).
470  *
471  * \since LTO_API_VERSION=5
472  */
473 extern lto_bool_t
474 lto_codegen_write_merged_modules(lto_code_gen_t cg, const char* path);
475 
476 /**
477  * Generates code for all added modules into one native object file.
478  * This calls lto_codegen_optimize then lto_codegen_compile_optimized.
479  *
480  * On success returns a pointer to a generated mach-o/ELF buffer and
481  * length set to the buffer size.  The buffer is owned by the
482  * lto_code_gen_t and will be freed when lto_codegen_dispose()
483  * is called, or lto_codegen_compile() is called again.
484  * On failure, returns NULL (check lto_get_error_message() for details).
485  *
486  * \since prior to LTO_API_VERSION=3
487  */
488 extern const void*
489 lto_codegen_compile(lto_code_gen_t cg, size_t* length);
490 
491 /**
492  * Generates code for all added modules into one native object file.
493  * This calls lto_codegen_optimize then lto_codegen_compile_optimized (instead
494  * of returning a generated mach-o/ELF buffer, it writes to a file).
495  *
496  * The name of the file is written to name. Returns true on error.
497  *
498  * \since LTO_API_VERSION=5
499  */
500 extern lto_bool_t
501 lto_codegen_compile_to_file(lto_code_gen_t cg, const char** name);
502 
503 /**
504  * Runs optimization for the merged module. Returns true on error.
505  *
506  * \since LTO_API_VERSION=12
507  */
508 extern lto_bool_t
509 lto_codegen_optimize(lto_code_gen_t cg);
510 
511 /**
512  * Generates code for the optimized merged module into one native object file.
513  * It will not run any IR optimizations on the merged module.
514  *
515  * On success returns a pointer to a generated mach-o/ELF buffer and length set
516  * to the buffer size.  The buffer is owned by the lto_code_gen_t and will be
517  * freed when lto_codegen_dispose() is called, or
518  * lto_codegen_compile_optimized() is called again. On failure, returns NULL
519  * (check lto_get_error_message() for details).
520  *
521  * \since LTO_API_VERSION=12
522  */
523 extern const void*
524 lto_codegen_compile_optimized(lto_code_gen_t cg, size_t* length);
525 
526 /**
527  * Returns the runtime API version.
528  *
529  * \since LTO_API_VERSION=12
530  */
531 extern unsigned int
532 lto_api_version(void);
533 
534 /**
535  * Sets options to help debug codegen bugs.
536  *
537  * \since prior to LTO_API_VERSION=3
538  */
539 extern void
540 lto_codegen_debug_options(lto_code_gen_t cg, const char *);
541 
542 /**
543  * Initializes LLVM disassemblers.
544  * FIXME: This doesn't really belong here.
545  *
546  * \since LTO_API_VERSION=5
547  */
548 extern void
549 lto_initialize_disassembler(void);
550 
551 #ifdef __cplusplus
552 }
553 #endif
554 
555 /**
556  * @}
557  */
558 
559 #endif
560