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#ifdef __cplusplus
20#include <cstddef>
21#else
22#include <stddef.h>
23#endif
24#include <sys/types.h>
25
26#ifndef __cplusplus
27#if !defined(_MSC_VER)
28#include <stdbool.h>
29typedef bool lto_bool_t;
30#else
31/* MSVC in particular does not have anything like _Bool or bool in C, but we can
32   at least make sure the type is the same size.  The implementation side will
33   use C++ bool. */
34typedef unsigned char lto_bool_t;
35#endif
36#else
37typedef bool lto_bool_t;
38#endif
39
40/**
41 * @defgroup LLVMCLTO LTO
42 * @ingroup LLVMC
43 *
44 * @{
45 */
46
47#define LTO_API_VERSION 20
48
49/**
50 * \since prior to LTO_API_VERSION=3
51 */
52typedef enum {
53    LTO_SYMBOL_ALIGNMENT_MASK              = 0x0000001F, /* log2 of alignment */
54    LTO_SYMBOL_PERMISSIONS_MASK            = 0x000000E0,
55    LTO_SYMBOL_PERMISSIONS_CODE            = 0x000000A0,
56    LTO_SYMBOL_PERMISSIONS_DATA            = 0x000000C0,
57    LTO_SYMBOL_PERMISSIONS_RODATA          = 0x00000080,
58    LTO_SYMBOL_DEFINITION_MASK             = 0x00000700,
59    LTO_SYMBOL_DEFINITION_REGULAR          = 0x00000100,
60    LTO_SYMBOL_DEFINITION_TENTATIVE        = 0x00000200,
61    LTO_SYMBOL_DEFINITION_WEAK             = 0x00000300,
62    LTO_SYMBOL_DEFINITION_UNDEFINED        = 0x00000400,
63    LTO_SYMBOL_DEFINITION_WEAKUNDEF        = 0x00000500,
64    LTO_SYMBOL_SCOPE_MASK                  = 0x00003800,
65    LTO_SYMBOL_SCOPE_INTERNAL              = 0x00000800,
66    LTO_SYMBOL_SCOPE_HIDDEN                = 0x00001000,
67    LTO_SYMBOL_SCOPE_PROTECTED             = 0x00002000,
68    LTO_SYMBOL_SCOPE_DEFAULT               = 0x00001800,
69    LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN = 0x00002800,
70    LTO_SYMBOL_COMDAT                      = 0x00004000,
71    LTO_SYMBOL_ALIAS                       = 0x00008000
72} lto_symbol_attributes;
73
74/**
75 * \since prior to LTO_API_VERSION=3
76 */
77typedef enum {
78    LTO_DEBUG_MODEL_NONE         = 0,
79    LTO_DEBUG_MODEL_DWARF        = 1
80} lto_debug_model;
81
82/**
83 * \since prior to LTO_API_VERSION=3
84 */
85typedef enum {
86    LTO_CODEGEN_PIC_MODEL_STATIC         = 0,
87    LTO_CODEGEN_PIC_MODEL_DYNAMIC        = 1,
88    LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC = 2,
89    LTO_CODEGEN_PIC_MODEL_DEFAULT        = 3
90} lto_codegen_model;
91
92/** opaque reference to a loaded object module */
93typedef struct LLVMOpaqueLTOModule *lto_module_t;
94
95/** opaque reference to a code generator */
96typedef struct LLVMOpaqueLTOCodeGenerator *lto_code_gen_t;
97
98/** opaque reference to a thin code generator */
99typedef struct LLVMOpaqueThinLTOCodeGenerator *thinlto_code_gen_t;
100
101#ifdef __cplusplus
102extern "C" {
103#endif
104
105/**
106 * Returns a printable string.
107 *
108 * \since prior to LTO_API_VERSION=3
109 */
110extern const char*
111lto_get_version(void);
112
113/**
114 * Returns the last error string or NULL if last operation was successful.
115 *
116 * \since prior to LTO_API_VERSION=3
117 */
118extern const char*
119lto_get_error_message(void);
120
121/**
122 * Checks if a file is a loadable object file.
123 *
124 * \since prior to LTO_API_VERSION=3
125 */
126extern lto_bool_t
127lto_module_is_object_file(const char* path);
128
129/**
130 * Checks if a file is a loadable object compiled for requested target.
131 *
132 * \since prior to LTO_API_VERSION=3
133 */
134extern lto_bool_t
135lto_module_is_object_file_for_target(const char* path,
136                                     const char* target_triple_prefix);
137
138/**
139 * Return true if \p Buffer contains a bitcode file with ObjC code (category
140 * or class) in it.
141 *
142 * \since LTO_API_VERSION=20
143 */
144extern lto_bool_t
145lto_module_has_objc_category(const void *mem, size_t length);
146
147/**
148* Checks if a buffer is a loadable object file.
149*
150* \since prior to LTO_API_VERSION=3
151*/
152extern lto_bool_t lto_module_is_object_file_in_memory(const void *mem,
153                                                      size_t length);
154
155/**
156 * Checks if a buffer is a loadable object compiled for requested target.
157 *
158 * \since prior to LTO_API_VERSION=3
159 */
160extern lto_bool_t
161lto_module_is_object_file_in_memory_for_target(const void* mem, size_t length,
162                                              const char* target_triple_prefix);
163
164/**
165 * Loads an object file from disk.
166 * Returns NULL on error (check lto_get_error_message() for details).
167 *
168 * \since prior to LTO_API_VERSION=3
169 */
170extern lto_module_t
171lto_module_create(const char* path);
172
173/**
174 * Loads an object file from memory.
175 * Returns NULL on error (check lto_get_error_message() for details).
176 *
177 * \since prior to LTO_API_VERSION=3
178 */
179extern lto_module_t
180lto_module_create_from_memory(const void* mem, size_t length);
181
182/**
183 * Loads an object file from memory with an extra path argument.
184 * Returns NULL on error (check lto_get_error_message() for details).
185 *
186 * \since LTO_API_VERSION=9
187 */
188extern lto_module_t
189lto_module_create_from_memory_with_path(const void* mem, size_t length,
190                                        const char *path);
191
192/**
193 * \brief Loads an object file in its own context.
194 *
195 * Loads an object file in its own LLVMContext.  This function call is
196 * thread-safe.  However, modules created this way should not be merged into an
197 * lto_code_gen_t using \a lto_codegen_add_module().
198 *
199 * Returns NULL on error (check lto_get_error_message() for details).
200 *
201 * \since LTO_API_VERSION=11
202 */
203extern lto_module_t
204lto_module_create_in_local_context(const void *mem, size_t length,
205                                   const char *path);
206
207/**
208 * \brief Loads an object file in the codegen context.
209 *
210 * Loads an object file into the same context as \c cg.  The module is safe to
211 * add using \a lto_codegen_add_module().
212 *
213 * Returns NULL on error (check lto_get_error_message() for details).
214 *
215 * \since LTO_API_VERSION=11
216 */
217extern lto_module_t
218lto_module_create_in_codegen_context(const void *mem, size_t length,
219                                     const char *path, lto_code_gen_t cg);
220
221/**
222 * Loads an object file from disk. The seek point of fd is not preserved.
223 * Returns NULL on error (check lto_get_error_message() for details).
224 *
225 * \since LTO_API_VERSION=5
226 */
227extern lto_module_t
228lto_module_create_from_fd(int fd, const char *path, size_t file_size);
229
230/**
231 * Loads an object file from disk. The seek point of fd is not preserved.
232 * Returns NULL on error (check lto_get_error_message() for details).
233 *
234 * \since LTO_API_VERSION=5
235 */
236extern lto_module_t
237lto_module_create_from_fd_at_offset(int fd, const char *path, size_t file_size,
238                                    size_t map_size, off_t offset);
239
240/**
241 * Frees all memory internally allocated by the module.
242 * Upon return the lto_module_t is no longer valid.
243 *
244 * \since prior to LTO_API_VERSION=3
245 */
246extern void
247lto_module_dispose(lto_module_t mod);
248
249/**
250 * Returns triple string which the object module was compiled under.
251 *
252 * \since prior to LTO_API_VERSION=3
253 */
254extern const char*
255lto_module_get_target_triple(lto_module_t mod);
256
257/**
258 * Sets triple string with which the object will be codegened.
259 *
260 * \since LTO_API_VERSION=4
261 */
262extern void
263lto_module_set_target_triple(lto_module_t mod, const char *triple);
264
265/**
266 * Returns the number of symbols in the object module.
267 *
268 * \since prior to LTO_API_VERSION=3
269 */
270extern unsigned int
271lto_module_get_num_symbols(lto_module_t mod);
272
273/**
274 * Returns the name of the ith symbol in the object module.
275 *
276 * \since prior to LTO_API_VERSION=3
277 */
278extern const char*
279lto_module_get_symbol_name(lto_module_t mod, unsigned int index);
280
281/**
282 * Returns the attributes of the ith symbol in the object module.
283 *
284 * \since prior to LTO_API_VERSION=3
285 */
286extern lto_symbol_attributes
287lto_module_get_symbol_attribute(lto_module_t mod, unsigned int index);
288
289/**
290 * Returns the module's linker options.
291 *
292 * The linker options may consist of multiple flags. It is the linker's
293 * responsibility to split the flags using a platform-specific mechanism.
294 *
295 * \since LTO_API_VERSION=16
296 */
297extern const char*
298lto_module_get_linkeropts(lto_module_t mod);
299
300/**
301 * Diagnostic severity.
302 *
303 * \since LTO_API_VERSION=7
304 */
305typedef enum {
306  LTO_DS_ERROR = 0,
307  LTO_DS_WARNING = 1,
308  LTO_DS_REMARK = 3, // Added in LTO_API_VERSION=10.
309  LTO_DS_NOTE = 2
310} lto_codegen_diagnostic_severity_t;
311
312/**
313 * Diagnostic handler type.
314 * \p severity defines the severity.
315 * \p diag is the actual diagnostic.
316 * The diagnostic is not prefixed by any of severity keyword, e.g., 'error: '.
317 * \p ctxt is used to pass the context set with the diagnostic handler.
318 *
319 * \since LTO_API_VERSION=7
320 */
321typedef void (*lto_diagnostic_handler_t)(
322    lto_codegen_diagnostic_severity_t severity, const char *diag, void *ctxt);
323
324/**
325 * Set a diagnostic handler and the related context (void *).
326 * This is more general than lto_get_error_message, as the diagnostic handler
327 * can be called at anytime within lto.
328 *
329 * \since LTO_API_VERSION=7
330 */
331extern void lto_codegen_set_diagnostic_handler(lto_code_gen_t,
332                                               lto_diagnostic_handler_t,
333                                               void *);
334
335/**
336 * Instantiates a code generator.
337 * Returns NULL on error (check lto_get_error_message() for details).
338 *
339 * All modules added using \a lto_codegen_add_module() must have been created
340 * in the same context as the codegen.
341 *
342 * \since prior to LTO_API_VERSION=3
343 */
344extern lto_code_gen_t
345lto_codegen_create(void);
346
347/**
348 * \brief Instantiate a code generator in its own context.
349 *
350 * Instantiates a code generator in its own context.  Modules added via \a
351 * lto_codegen_add_module() must have all been created in the same context,
352 * using \a lto_module_create_in_codegen_context().
353 *
354 * \since LTO_API_VERSION=11
355 */
356extern lto_code_gen_t
357lto_codegen_create_in_local_context(void);
358
359/**
360 * Frees all code generator and all memory it internally allocated.
361 * Upon return the lto_code_gen_t is no longer valid.
362 *
363 * \since prior to LTO_API_VERSION=3
364 */
365extern void
366lto_codegen_dispose(lto_code_gen_t);
367
368/**
369 * Add an object module to the set of modules for which code will be generated.
370 * Returns true on error (check lto_get_error_message() for details).
371 *
372 * \c cg and \c mod must both be in the same context.  See \a
373 * lto_codegen_create_in_local_context() and \a
374 * lto_module_create_in_codegen_context().
375 *
376 * \since prior to LTO_API_VERSION=3
377 */
378extern lto_bool_t
379lto_codegen_add_module(lto_code_gen_t cg, lto_module_t mod);
380
381/**
382 * Sets the object module for code generation. This will transfer the ownership
383 * of the module to the code generator.
384 *
385 * \c cg and \c mod must both be in the same context.
386 *
387 * \since LTO_API_VERSION=13
388 */
389extern void
390lto_codegen_set_module(lto_code_gen_t cg, lto_module_t mod);
391
392/**
393 * Sets if debug info should be generated.
394 * Returns true on error (check lto_get_error_message() for details).
395 *
396 * \since prior to LTO_API_VERSION=3
397 */
398extern lto_bool_t
399lto_codegen_set_debug_model(lto_code_gen_t cg, lto_debug_model);
400
401/**
402 * Sets which PIC code model to generated.
403 * Returns true on error (check lto_get_error_message() for details).
404 *
405 * \since prior to LTO_API_VERSION=3
406 */
407extern lto_bool_t
408lto_codegen_set_pic_model(lto_code_gen_t cg, lto_codegen_model);
409
410/**
411 * Sets the cpu to generate code for.
412 *
413 * \since LTO_API_VERSION=4
414 */
415extern void
416lto_codegen_set_cpu(lto_code_gen_t cg, const char *cpu);
417
418/**
419 * Sets the location of the assembler tool to run. If not set, libLTO
420 * will use gcc to invoke the assembler.
421 *
422 * \since LTO_API_VERSION=3
423 */
424extern void
425lto_codegen_set_assembler_path(lto_code_gen_t cg, const char* path);
426
427/**
428 * Sets extra arguments that libLTO should pass to the assembler.
429 *
430 * \since LTO_API_VERSION=4
431 */
432extern void
433lto_codegen_set_assembler_args(lto_code_gen_t cg, const char **args,
434                               int nargs);
435
436/**
437 * Adds to a list of all global symbols that must exist in the final generated
438 * code. If a function is not listed there, it might be inlined into every usage
439 * and optimized away.
440 *
441 * \since prior to LTO_API_VERSION=3
442 */
443extern void
444lto_codegen_add_must_preserve_symbol(lto_code_gen_t cg, const char* symbol);
445
446/**
447 * Writes a new object file at the specified path that contains the
448 * merged contents of all modules added so far.
449 * Returns true on error (check lto_get_error_message() for details).
450 *
451 * \since LTO_API_VERSION=5
452 */
453extern lto_bool_t
454lto_codegen_write_merged_modules(lto_code_gen_t cg, const char* path);
455
456/**
457 * Generates code for all added modules into one native object file.
458 * This calls lto_codegen_optimize then lto_codegen_compile_optimized.
459 *
460 * On success returns a pointer to a generated mach-o/ELF buffer and
461 * length set to the buffer size.  The buffer is owned by the
462 * lto_code_gen_t and will be freed when lto_codegen_dispose()
463 * is called, or lto_codegen_compile() is called again.
464 * On failure, returns NULL (check lto_get_error_message() for details).
465 *
466 * \since prior to LTO_API_VERSION=3
467 */
468extern const void*
469lto_codegen_compile(lto_code_gen_t cg, size_t* length);
470
471/**
472 * Generates code for all added modules into one native object file.
473 * This calls lto_codegen_optimize then lto_codegen_compile_optimized (instead
474 * of returning a generated mach-o/ELF buffer, it writes to a file).
475 *
476 * The name of the file is written to name. Returns true on error.
477 *
478 * \since LTO_API_VERSION=5
479 */
480extern lto_bool_t
481lto_codegen_compile_to_file(lto_code_gen_t cg, const char** name);
482
483/**
484 * Runs optimization for the merged module. Returns true on error.
485 *
486 * \since LTO_API_VERSION=12
487 */
488extern lto_bool_t
489lto_codegen_optimize(lto_code_gen_t cg);
490
491/**
492 * Generates code for the optimized merged module into one native object file.
493 * It will not run any IR optimizations on the merged module.
494 *
495 * On success returns a pointer to a generated mach-o/ELF buffer and length set
496 * to the buffer size.  The buffer is owned by the lto_code_gen_t and will be
497 * freed when lto_codegen_dispose() is called, or
498 * lto_codegen_compile_optimized() is called again. On failure, returns NULL
499 * (check lto_get_error_message() for details).
500 *
501 * \since LTO_API_VERSION=12
502 */
503extern const void*
504lto_codegen_compile_optimized(lto_code_gen_t cg, size_t* length);
505
506/**
507 * Returns the runtime API version.
508 *
509 * \since LTO_API_VERSION=12
510 */
511extern unsigned int
512lto_api_version(void);
513
514/**
515 * Sets options to help debug codegen bugs.
516 *
517 * \since prior to LTO_API_VERSION=3
518 */
519extern void
520lto_codegen_debug_options(lto_code_gen_t cg, const char *);
521
522/**
523 * Initializes LLVM disassemblers.
524 * FIXME: This doesn't really belong here.
525 *
526 * \since LTO_API_VERSION=5
527 */
528extern void
529lto_initialize_disassembler(void);
530
531/**
532 * Sets if we should run internalize pass during optimization and code
533 * generation.
534 *
535 * \since LTO_API_VERSION=14
536 */
537extern void
538lto_codegen_set_should_internalize(lto_code_gen_t cg,
539                                   lto_bool_t ShouldInternalize);
540
541/**
542 * \brief Set whether to embed uselists in bitcode.
543 *
544 * Sets whether \a lto_codegen_write_merged_modules() should embed uselists in
545 * output bitcode.  This should be turned on for all -save-temps output.
546 *
547 * \since LTO_API_VERSION=15
548 */
549extern void
550lto_codegen_set_should_embed_uselists(lto_code_gen_t cg,
551                                      lto_bool_t ShouldEmbedUselists);
552
553/**
554 * @}
555 * @defgroup LLVMCTLTO ThinLTO
556 * @ingroup LLVMC
557 *
558 * @{
559 */
560
561/**
562 * Type to wrap a single object returned by ThinLTO.
563 *
564 * \since LTO_API_VERSION=18
565 */
566typedef struct {
567  const char *Buffer;
568  size_t Size;
569} LTOObjectBuffer;
570
571/**
572 * Instantiates a ThinLTO code generator.
573 * Returns NULL on error (check lto_get_error_message() for details).
574 *
575 *
576 * The ThinLTOCodeGenerator is not intended to be reuse for multiple
577 * compilation: the model is that the client adds modules to the generator and
578 * ask to perform the ThinLTO optimizations / codegen, and finally destroys the
579 * codegenerator.
580 *
581 * \since LTO_API_VERSION=18
582 */
583extern thinlto_code_gen_t thinlto_create_codegen(void);
584
585/**
586 * Frees the generator and all memory it internally allocated.
587 * Upon return the thinlto_code_gen_t is no longer valid.
588 *
589 * \since LTO_API_VERSION=18
590 */
591extern void thinlto_codegen_dispose(thinlto_code_gen_t cg);
592
593/**
594 * Add a module to a ThinLTO code generator. Identifier has to be unique among
595 * all the modules in a code generator. The data buffer stays owned by the
596 * client, and is expected to be available for the entire lifetime of the
597 * thinlto_code_gen_t it is added to.
598 *
599 * On failure, returns NULL (check lto_get_error_message() for details).
600 *
601 *
602 * \since LTO_API_VERSION=18
603 */
604extern void thinlto_codegen_add_module(thinlto_code_gen_t cg,
605                                       const char *identifier, const char *data,
606                                       int length);
607
608/**
609 * Optimize and codegen all the modules added to the codegenerator using
610 * ThinLTO. Resulting objects are accessible using thinlto_module_get_object().
611 *
612 * \since LTO_API_VERSION=18
613 */
614extern void thinlto_codegen_process(thinlto_code_gen_t cg);
615
616/**
617 * Returns the number of object files produced by the ThinLTO CodeGenerator.
618 *
619 * It usually matches the number of input files, but this is not a guarantee of
620 * the API and may change in future implementation, so the client should not
621 * assume it.
622 *
623 * \since LTO_API_VERSION=18
624 */
625extern unsigned int thinlto_module_get_num_objects(thinlto_code_gen_t cg);
626
627/**
628 * Returns a reference to the ith object file produced by the ThinLTO
629 * CodeGenerator.
630 *
631 * Client should use \p thinlto_module_get_num_objects() to get the number of
632 * available objects.
633 *
634 * \since LTO_API_VERSION=18
635 */
636extern LTOObjectBuffer thinlto_module_get_object(thinlto_code_gen_t cg,
637                                                 unsigned int index);
638
639/**
640 * Sets which PIC code model to generate.
641 * Returns true on error (check lto_get_error_message() for details).
642 *
643 * \since LTO_API_VERSION=18
644 */
645extern lto_bool_t thinlto_codegen_set_pic_model(thinlto_code_gen_t cg,
646                                                lto_codegen_model);
647
648/**
649 * @}
650 * @defgroup LLVMCTLTO_CACHING ThinLTO Cache Control
651 * @ingroup LLVMCTLTO
652 *
653 * These entry points control the ThinLTO cache. The cache is intended to
654 * support incremental build, and thus needs to be persistent accross build.
655 * The client enabled the cache by supplying a path to an existing directory.
656 * The code generator will use this to store objects files that may be reused
657 * during a subsequent build.
658 * To avoid filling the disk space, a few knobs are provided:
659 *  - The pruning interval limit the frequency at which the garbage collector
660 *    will try to scan the cache directory to prune it from expired entries.
661 *    Setting to -1 disable the pruning (default).
662 *  - The pruning expiration time indicates to the garbage collector how old an
663 *    entry needs to be to be removed.
664 *  - Finally, the garbage collector can be instructed to prune the cache till
665 *    the occupied space goes below a threshold.
666 * @{
667 */
668
669/**
670 * Sets the path to a directory to use as a cache storage for incremental build.
671 * Setting this activates caching.
672 *
673 * \since LTO_API_VERSION=18
674 */
675extern void thinlto_codegen_set_cache_dir(thinlto_code_gen_t cg,
676                                          const char *cache_dir);
677
678/**
679 * Sets the cache pruning interval (in seconds). A negative value disable the
680 * pruning. An unspecified default value will be applied, and a value of 0 will
681 * be ignored.
682 *
683 * \since LTO_API_VERSION=18
684 */
685extern void thinlto_codegen_set_cache_pruning_interval(thinlto_code_gen_t cg,
686                                                       int interval);
687
688/**
689 * Sets the maximum cache size that can be persistent across build, in terms of
690 * percentage of the available space on the the disk. Set to 100 to indicate
691 * no limit, 50 to indicate that the cache size will not be left over half the
692 * available space. A value over 100 will be reduced to 100, a value of 0 will
693 * be ignored. An unspecified default value will be applied.
694 *
695 * The formula looks like:
696 *  AvailableSpace = FreeSpace + ExistingCacheSize
697 *  NewCacheSize = AvailableSpace * P/100
698 *
699 * \since LTO_API_VERSION=18
700 */
701extern void thinlto_codegen_set_final_cache_size_relative_to_available_space(
702    thinlto_code_gen_t cg, unsigned percentage);
703
704/**
705 * Sets the expiration (in seconds) for an entry in the cache. An unspecified
706 * default value will be applied. A value of 0 will be ignored.
707 *
708 * \since LTO_API_VERSION=18
709 */
710extern void thinlto_codegen_set_cache_entry_expiration(thinlto_code_gen_t cg,
711                                                       unsigned expiration);
712
713/**
714 * @}
715 */
716
717/**
718 * Sets the path to a directory to use as a storage for temporary bitcode files.
719 * The intention is to make the bitcode files available for debugging at various
720 * stage of the pipeline.
721 *
722 * \since LTO_API_VERSION=18
723 */
724extern void thinlto_codegen_set_savetemps_dir(thinlto_code_gen_t cg,
725                                              const char *save_temps_dir);
726
727/**
728 * Sets the cpu to generate code for.
729 *
730 * \since LTO_API_VERSION=18
731 */
732extern void thinlto_codegen_set_cpu(thinlto_code_gen_t cg, const char *cpu);
733
734/**
735 * Disable CodeGen, only run the stages till codegen and stop. The output will
736 * be bitcode.
737 *
738 * \since LTO_API_VERSION=19
739 */
740extern void thinlto_codegen_disable_codegen(thinlto_code_gen_t cg,
741                                            lto_bool_t disable);
742
743/**
744 * Perform CodeGen only: disable all other stages.
745 *
746 * \since LTO_API_VERSION=19
747 */
748extern void thinlto_codegen_set_codegen_only(thinlto_code_gen_t cg,
749                                             lto_bool_t codegen_only);
750
751/**
752 * Parse -mllvm style debug options.
753 *
754 * \since LTO_API_VERSION=18
755 */
756extern void thinlto_debug_options(const char *const *options, int number);
757
758/**
759 * Test if a module has support for ThinLTO linking.
760 *
761 * \since LTO_API_VERSION=18
762 */
763extern lto_bool_t lto_module_is_thinlto(lto_module_t mod);
764
765/**
766 * Adds a symbol to the list of global symbols that must exist in the final
767 * generated code. If a function is not listed there, it might be inlined into
768 * every usage and optimized away. For every single module, the functions
769 * referenced from code outside of the ThinLTO modules need to be added here.
770 *
771 * \since LTO_API_VERSION=18
772 */
773extern void thinlto_codegen_add_must_preserve_symbol(thinlto_code_gen_t cg,
774                                                     const char *name,
775                                                     int length);
776
777/**
778 * Adds a symbol to the list of global symbols that are cross-referenced between
779 * ThinLTO files. If the ThinLTO CodeGenerator can ensure that every
780 * references from a ThinLTO module to this symbol is optimized away, then
781 * the symbol can be discarded.
782 *
783 * \since LTO_API_VERSION=18
784 */
785extern void thinlto_codegen_add_cross_referenced_symbol(thinlto_code_gen_t cg,
786                                                        const char *name,
787                                                        int length);
788
789#ifdef __cplusplus
790}
791#endif
792
793/**
794 * @}
795 */
796
797#endif /* LLVM_C_LTO_H */
798