1/*===-- llvm-c/lto.h - LTO Public C Interface ---------------------*- C -*-===*\
2|* *|
3|* Part of the LLVM Project, under the Apache License v2.0 with LLVM *|
4|* Exceptions. *|
5|* See https://llvm.org/LICENSE.txt for license information. *|
6|* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception *|
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 "llvm-c/ExternC.h"
20
21#ifdef __cplusplus
22#include <cstddef>
23#else
24#include <stddef.h>
25#endif
26#include <sys/types.h>
27
28#ifndef __cplusplus
29#if !defined(_MSC_VER)
30#include <stdbool.h>
31typedef bool lto_bool_t;
32#else
33/* MSVC in particular does not have anything like _Bool or bool in C, but we can
34 at least make sure the type is the same size. The implementation side will
35 use C++ bool. */
36typedef unsigned char lto_bool_t;
37#endif
38#else
39typedef bool lto_bool_t;
40#endif
41
42/**
43 * @defgroup LLVMCLTO LTO
44 * @ingroup LLVMC
45 *
46 * @{
47 */
48
49#define LTO_API_VERSION 29
50
51/**
52 * \since prior to LTO_API_VERSION=3
53 */
54typedef enum {
55 LTO_SYMBOL_ALIGNMENT_MASK = 0x0000001F, /* log2 of alignment */
56 LTO_SYMBOL_PERMISSIONS_MASK = 0x000000E0,
57 LTO_SYMBOL_PERMISSIONS_CODE = 0x000000A0,
58 LTO_SYMBOL_PERMISSIONS_DATA = 0x000000C0,
59 LTO_SYMBOL_PERMISSIONS_RODATA = 0x00000080,
60 LTO_SYMBOL_DEFINITION_MASK = 0x00000700,
61 LTO_SYMBOL_DEFINITION_REGULAR = 0x00000100,
62 LTO_SYMBOL_DEFINITION_TENTATIVE = 0x00000200,
63 LTO_SYMBOL_DEFINITION_WEAK = 0x00000300,
64 LTO_SYMBOL_DEFINITION_UNDEFINED = 0x00000400,
65 LTO_SYMBOL_DEFINITION_WEAKUNDEF = 0x00000500,
66 LTO_SYMBOL_SCOPE_MASK = 0x00003800,
67 LTO_SYMBOL_SCOPE_INTERNAL = 0x00000800,
68 LTO_SYMBOL_SCOPE_HIDDEN = 0x00001000,
69 LTO_SYMBOL_SCOPE_PROTECTED = 0x00002000,
70 LTO_SYMBOL_SCOPE_DEFAULT = 0x00001800,
71 LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN = 0x00002800,
72 LTO_SYMBOL_COMDAT = 0x00004000,
73 LTO_SYMBOL_ALIAS = 0x00008000
74} lto_symbol_attributes;
75
76/**
77 * \since prior to LTO_API_VERSION=3
78 */
79typedef enum {
80 LTO_DEBUG_MODEL_NONE = 0,
81 LTO_DEBUG_MODEL_DWARF = 1
82} lto_debug_model;
83
84/**
85 * \since prior to LTO_API_VERSION=3
86 */
87typedef enum {
88 LTO_CODEGEN_PIC_MODEL_STATIC = 0,
89 LTO_CODEGEN_PIC_MODEL_DYNAMIC = 1,
90 LTO_CODEGEN_PIC_MODEL_DYNAMIC_NO_PIC = 2,
91 LTO_CODEGEN_PIC_MODEL_DEFAULT = 3
92} lto_codegen_model;
93
94/** opaque reference to a loaded object module */
95typedef struct LLVMOpaqueLTOModule *lto_module_t;
96
97/** opaque reference to a code generator */
98typedef struct LLVMOpaqueLTOCodeGenerator *lto_code_gen_t;
99
100/** opaque reference to a thin code generator */
101typedef struct LLVMOpaqueThinLTOCodeGenerator *thinlto_code_gen_t;
102
103LLVM_C_EXTERN_C_BEGIN
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 * 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 * 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 * If targeting mach-o on darwin, this function gets the CPU type and subtype
302 * that will end up being encoded in the mach-o header. These are the values
303 * that can be found in mach/machine.h.
304 *
305 * \p out_cputype and \p out_cpusubtype must be non-NULL.
306 *
307 * Returns true on error (check lto_get_error_message() for details).
308 *
309 * \since LTO_API_VERSION=27
310 */
311extern lto_bool_t lto_module_get_macho_cputype(lto_module_t mod,
312 unsigned int *out_cputype,
313 unsigned int *out_cpusubtype);
314
315/**
316 * This function can be used by the linker to check if a given module has
317 * any constructor or destructor functions.
318 *
319 * Returns true if the module has either the @llvm.global_ctors or the
320 * @llvm.global_dtors symbol. Otherwise returns false.
321 *
322 * \since LTO_API_VERSION=29
323 */
324extern lto_bool_t lto_module_has_ctor_dtor(lto_module_t mod);
325/**
326 * Diagnostic severity.
327 *
328 * \since LTO_API_VERSION=7
329 */
330typedef enum {
331 LTO_DS_ERROR = 0,
332 LTO_DS_WARNING = 1,
333 LTO_DS_REMARK = 3, // Added in LTO_API_VERSION=10.
334 LTO_DS_NOTE = 2
335} lto_codegen_diagnostic_severity_t;
336
337/**
338 * Diagnostic handler type.
339 * \p severity defines the severity.
340 * \p diag is the actual diagnostic.
341 * The diagnostic is not prefixed by any of severity keyword, e.g., 'error: '.
342 * \p ctxt is used to pass the context set with the diagnostic handler.
343 *
344 * \since LTO_API_VERSION=7
345 */
346typedef void (*lto_diagnostic_handler_t)(
347 lto_codegen_diagnostic_severity_t severity, const char *diag, void *ctxt);
348
349/**
350 * Set a diagnostic handler and the related context (void *).
351 * This is more general than lto_get_error_message, as the diagnostic handler
352 * can be called at anytime within lto.
353 *
354 * \since LTO_API_VERSION=7
355 */
356extern void lto_codegen_set_diagnostic_handler(lto_code_gen_t,
357 lto_diagnostic_handler_t,
358 void *);
359
360/**
361 * Instantiates a code generator.
362 * Returns NULL on error (check lto_get_error_message() for details).
363 *
364 * All modules added using \a lto_codegen_add_module() must have been created
365 * in the same context as the codegen.
366 *
367 * \since prior to LTO_API_VERSION=3
368 */
369extern lto_code_gen_t
370lto_codegen_create(void);
371
372/**
373 * Instantiate a code generator in its own context.
374 *
375 * Instantiates a code generator in its own context. Modules added via \a
376 * lto_codegen_add_module() must have all been created in the same context,
377 * using \a lto_module_create_in_codegen_context().
378 *
379 * \since LTO_API_VERSION=11
380 */
381extern lto_code_gen_t
382lto_codegen_create_in_local_context(void);
383
384/**
385 * Frees all code generator and all memory it internally allocated.
386 * Upon return the lto_code_gen_t is no longer valid.
387 *
388 * \since prior to LTO_API_VERSION=3
389 */
390extern void
391lto_codegen_dispose(lto_code_gen_t);
392
393/**
394 * Add an object module to the set of modules for which code will be generated.
395 * Returns true on error (check lto_get_error_message() for details).
396 *
397 * \c cg and \c mod must both be in the same context. See \a
398 * lto_codegen_create_in_local_context() and \a
399 * lto_module_create_in_codegen_context().
400 *
401 * \since prior to LTO_API_VERSION=3
402 */
403extern lto_bool_t
404lto_codegen_add_module(lto_code_gen_t cg, lto_module_t mod);
405
406/**
407 * Sets the object module for code generation. This will transfer the ownership
408 * of the module to the code generator.
409 *
410 * \c cg and \c mod must both be in the same context.
411 *
412 * \since LTO_API_VERSION=13
413 */
414extern void
415lto_codegen_set_module(lto_code_gen_t cg, lto_module_t mod);
416
417/**
418 * Sets if debug info should be generated.
419 * Returns true on error (check lto_get_error_message() for details).
420 *
421 * \since prior to LTO_API_VERSION=3
422 */
423extern lto_bool_t
424lto_codegen_set_debug_model(lto_code_gen_t cg, lto_debug_model);
425
426/**
427 * Sets which PIC code model to generated.
428 * Returns true on error (check lto_get_error_message() for details).
429 *
430 * \since prior to LTO_API_VERSION=3
431 */
432extern lto_bool_t
433lto_codegen_set_pic_model(lto_code_gen_t cg, lto_codegen_model);
434
435/**
436 * Sets the cpu to generate code for.
437 *
438 * \since LTO_API_VERSION=4
439 */
440extern void
441lto_codegen_set_cpu(lto_code_gen_t cg, const char *cpu);
442
443/**
444 * Sets the location of the assembler tool to run. If not set, libLTO
445 * will use gcc to invoke the assembler.
446 *
447 * \since LTO_API_VERSION=3
448 */
449extern void
450lto_codegen_set_assembler_path(lto_code_gen_t cg, const char* path);
451
452/**
453 * Sets extra arguments that libLTO should pass to the assembler.
454 *
455 * \since LTO_API_VERSION=4
456 */
457extern void
458lto_codegen_set_assembler_args(lto_code_gen_t cg, const char **args,
459 int nargs);
460
461/**
462 * Adds to a list of all global symbols that must exist in the final generated
463 * code. If a function is not listed there, it might be inlined into every usage
464 * and optimized away.
465 *
466 * \since prior to LTO_API_VERSION=3
467 */
468extern void
469lto_codegen_add_must_preserve_symbol(lto_code_gen_t cg, const char* symbol);
470
471/**
472 * Writes a new object file at the specified path that contains the
473 * merged contents of all modules added so far.
474 * Returns true on error (check lto_get_error_message() for details).
475 *
476 * \since LTO_API_VERSION=5
477 */
478extern lto_bool_t
479lto_codegen_write_merged_modules(lto_code_gen_t cg, const char* path);
480
481/**
482 * Generates code for all added modules into one native object file.
483 * This calls lto_codegen_optimize then lto_codegen_compile_optimized.
484 *
485 * On success returns a pointer to a generated mach-o/ELF buffer and
486 * length set to the buffer size. The buffer is owned by the
487 * lto_code_gen_t and will be freed when lto_codegen_dispose()
488 * is called, or lto_codegen_compile() is called again.
489 * On failure, returns NULL (check lto_get_error_message() for details).
490 *
491 * \since prior to LTO_API_VERSION=3
492 */
493extern const void*
494lto_codegen_compile(lto_code_gen_t cg, size_t* length);
495
496/**
497 * Generates code for all added modules into one native object file.
498 * This calls lto_codegen_optimize then lto_codegen_compile_optimized (instead
499 * of returning a generated mach-o/ELF buffer, it writes to a file).
500 *
501 * The name of the file is written to name. Returns true on error.
502 *
503 * \since LTO_API_VERSION=5
504 */
505extern lto_bool_t
506lto_codegen_compile_to_file(lto_code_gen_t cg, const char** name);
507
508/**
509 * Runs optimization for the merged module. Returns true on error.
510 *
511 * \since LTO_API_VERSION=12
512 */
513extern lto_bool_t
514lto_codegen_optimize(lto_code_gen_t cg);
515
516/**
517 * Generates code for the optimized merged module into one native object file.
518 * It will not run any IR optimizations on the merged module.
519 *
520 * On success returns a pointer to a generated mach-o/ELF buffer and length set
521 * to the buffer size. The buffer is owned by the lto_code_gen_t and will be
522 * freed when lto_codegen_dispose() is called, or
523 * lto_codegen_compile_optimized() is called again. On failure, returns NULL
524 * (check lto_get_error_message() for details).
525 *
526 * \since LTO_API_VERSION=12
527 */
528extern const void*
529lto_codegen_compile_optimized(lto_code_gen_t cg, size_t* length);
530
531/**
532 * Returns the runtime API version.
533 *
534 * \since LTO_API_VERSION=12
535 */
536extern unsigned int
537lto_api_version(void);
538
539/**
540 * Parses options immediately, making them available as early as possible. For
541 * example during executing codegen::InitTargetOptionsFromCodeGenFlags. Since
542 * parsing shud only happen once, only one of lto_codegen_debug_options or
543 * lto_set_debug_options should be called.
544 *
545 * This function takes one or more options separated by spaces.
546 * Warning: passing file paths through this function may confuse the argument
547 * parser if the paths contain spaces.
548 *
549 * \since LTO_API_VERSION=28
550 */
551extern void lto_set_debug_options(const char *const *options, int number);
552
553/**
554 * Sets options to help debug codegen bugs. Since parsing shud only happen once,
555 * only one of lto_codegen_debug_options or lto_set_debug_options
556 * should be called.
557 *
558 * This function takes one or more options separated by spaces.
559 * Warning: passing file paths through this function may confuse the argument
560 * parser if the paths contain spaces.
561 *
562 * \since prior to LTO_API_VERSION=3
563 */
564extern void
565lto_codegen_debug_options(lto_code_gen_t cg, const char *);
566
567/**
568 * Same as the previous function, but takes every option separately through an
569 * array.
570 *
571 * \since prior to LTO_API_VERSION=26
572 */
573extern void lto_codegen_debug_options_array(lto_code_gen_t cg,
574 const char *const *, int number);
575
576/**
577 * Initializes LLVM disassemblers.
578 * FIXME: This doesn't really belong here.
579 *
580 * \since LTO_API_VERSION=5
581 */
582extern void
583lto_initialize_disassembler(void);
584
585/**
586 * Sets if we should run internalize pass during optimization and code
587 * generation.
588 *
589 * \since LTO_API_VERSION=14
590 */
591extern void
592lto_codegen_set_should_internalize(lto_code_gen_t cg,
593 lto_bool_t ShouldInternalize);
594
595/**
596 * Set whether to embed uselists in bitcode.
597 *
598 * Sets whether \a lto_codegen_write_merged_modules() should embed uselists in
599 * output bitcode. This should be turned on for all -save-temps output.
600 *
601 * \since LTO_API_VERSION=15
602 */
603extern void
604lto_codegen_set_should_embed_uselists(lto_code_gen_t cg,
605 lto_bool_t ShouldEmbedUselists);
606
607/** Opaque reference to an LTO input file */
608typedef struct LLVMOpaqueLTOInput *lto_input_t;
609
610/**
611 * Creates an LTO input file from a buffer. The path
612 * argument is used for diagnotics as this function
613 * otherwise does not know which file the given buffer
614 * is associated with.
615 *
616 * \since LTO_API_VERSION=24
617 */
618extern lto_input_t lto_input_create(const void *buffer,
619 size_t buffer_size,
620 const char *path);
621
622/**
623 * Frees all memory internally allocated by the LTO input file.
624 * Upon return the lto_module_t is no longer valid.
625 *
626 * \since LTO_API_VERSION=24
627 */
628extern void lto_input_dispose(lto_input_t input);
629
630/**
631 * Returns the number of dependent library specifiers
632 * for the given LTO input file.
633 *
634 * \since LTO_API_VERSION=24
635 */
636extern unsigned lto_input_get_num_dependent_libraries(lto_input_t input);
637
638/**
639 * Returns the ith dependent library specifier
640 * for the given LTO input file. The returned
641 * string is not null-terminated.
642 *
643 * \since LTO_API_VERSION=24
644 */
645extern const char * lto_input_get_dependent_library(lto_input_t input,
646 size_t index,
647 size_t *size);
648
649/**
650 * Returns the list of libcall symbols that can be generated by LTO
651 * that might not be visible from the symbol table of bitcode files.
652 *
653 * \since prior to LTO_API_VERSION=25
654 */
655extern const char *const *lto_runtime_lib_symbols_list(size_t *size);
656
657/**
658 * @} // endgoup LLVMCLTO
659 * @defgroup LLVMCTLTO ThinLTO
660 * @ingroup LLVMC
661 *
662 * @{
663 */
664
665/**
666 * Type to wrap a single object returned by ThinLTO.
667 *
668 * \since LTO_API_VERSION=18
669 */
670typedef struct {
671 const char *Buffer;
672 size_t Size;
673} LTOObjectBuffer;
674
675/**
676 * Instantiates a ThinLTO code generator.
677 * Returns NULL on error (check lto_get_error_message() for details).
678 *
679 *
680 * The ThinLTOCodeGenerator is not intended to be reuse for multiple
681 * compilation: the model is that the client adds modules to the generator and
682 * ask to perform the ThinLTO optimizations / codegen, and finally destroys the
683 * codegenerator.
684 *
685 * \since LTO_API_VERSION=18
686 */
687extern thinlto_code_gen_t thinlto_create_codegen(void);
688
689/**
690 * Frees the generator and all memory it internally allocated.
691 * Upon return the thinlto_code_gen_t is no longer valid.
692 *
693 * \since LTO_API_VERSION=18
694 */
695extern void thinlto_codegen_dispose(thinlto_code_gen_t cg);
696
697/**
698 * Add a module to a ThinLTO code generator. Identifier has to be unique among
699 * all the modules in a code generator. The data buffer stays owned by the
700 * client, and is expected to be available for the entire lifetime of the
701 * thinlto_code_gen_t it is added to.
702 *
703 * On failure, returns NULL (check lto_get_error_message() for details).
704 *
705 *
706 * \since LTO_API_VERSION=18
707 */
708extern void thinlto_codegen_add_module(thinlto_code_gen_t cg,
709 const char *identifier, const char *data,
710 int length);
711
712/**
713 * Optimize and codegen all the modules added to the codegenerator using
714 * ThinLTO. Resulting objects are accessible using thinlto_module_get_object().
715 *
716 * \since LTO_API_VERSION=18
717 */
718extern void thinlto_codegen_process(thinlto_code_gen_t cg);
719
720/**
721 * Returns the number of object files produced by the ThinLTO CodeGenerator.
722 *
723 * It usually matches the number of input files, but this is not a guarantee of
724 * the API and may change in future implementation, so the client should not
725 * assume it.
726 *
727 * \since LTO_API_VERSION=18
728 */
729extern unsigned int thinlto_module_get_num_objects(thinlto_code_gen_t cg);
730
731/**
732 * Returns a reference to the ith object file produced by the ThinLTO
733 * CodeGenerator.
734 *
735 * Client should use \p thinlto_module_get_num_objects() to get the number of
736 * available objects.
737 *
738 * \since LTO_API_VERSION=18
739 */
740extern LTOObjectBuffer thinlto_module_get_object(thinlto_code_gen_t cg,
741 unsigned int index);
742
743/**
744 * Returns the number of object files produced by the ThinLTO CodeGenerator.
745 *
746 * It usually matches the number of input files, but this is not a guarantee of
747 * the API and may change in future implementation, so the client should not
748 * assume it.
749 *
750 * \since LTO_API_VERSION=21
751 */
752unsigned int thinlto_module_get_num_object_files(thinlto_code_gen_t cg);
753
754/**
755 * Returns the path to the ith object file produced by the ThinLTO
756 * CodeGenerator.
757 *
758 * Client should use \p thinlto_module_get_num_object_files() to get the number
759 * of available objects.
760 *
761 * \since LTO_API_VERSION=21
762 */
763const char *thinlto_module_get_object_file(thinlto_code_gen_t cg,
764 unsigned int index);
765
766/**
767 * Sets which PIC code model to generate.
768 * Returns true on error (check lto_get_error_message() for details).
769 *
770 * \since LTO_API_VERSION=18
771 */
772extern lto_bool_t thinlto_codegen_set_pic_model(thinlto_code_gen_t cg,
773 lto_codegen_model);
774
775/**
776 * Sets the path to a directory to use as a storage for temporary bitcode files.
777 * The intention is to make the bitcode files available for debugging at various
778 * stage of the pipeline.
779 *
780 * \since LTO_API_VERSION=18
781 */
782extern void thinlto_codegen_set_savetemps_dir(thinlto_code_gen_t cg,
783 const char *save_temps_dir);
784
785/**
786 * Set the path to a directory where to save generated object files. This
787 * path can be used by a linker to request on-disk files instead of in-memory
788 * buffers. When set, results are available through
789 * thinlto_module_get_object_file() instead of thinlto_module_get_object().
790 *
791 * \since LTO_API_VERSION=21
792 */
793void thinlto_set_generated_objects_dir(thinlto_code_gen_t cg,
794 const char *save_temps_dir);
795
796/**
797 * Sets the cpu to generate code for.
798 *
799 * \since LTO_API_VERSION=18
800 */
801extern void thinlto_codegen_set_cpu(thinlto_code_gen_t cg, const char *cpu);
802
803/**
804 * Disable CodeGen, only run the stages till codegen and stop. The output will
805 * be bitcode.
806 *
807 * \since LTO_API_VERSION=19
808 */
809extern void thinlto_codegen_disable_codegen(thinlto_code_gen_t cg,
810 lto_bool_t disable);
811
812/**
813 * Perform CodeGen only: disable all other stages.
814 *
815 * \since LTO_API_VERSION=19
816 */
817extern void thinlto_codegen_set_codegen_only(thinlto_code_gen_t cg,
818 lto_bool_t codegen_only);
819
820/**
821 * Parse -mllvm style debug options.
822 *
823 * \since LTO_API_VERSION=18
824 */
825extern void thinlto_debug_options(const char *const *options, int number);
826
827/**
828 * Test if a module has support for ThinLTO linking.
829 *
830 * \since LTO_API_VERSION=18
831 */
832extern lto_bool_t lto_module_is_thinlto(lto_module_t mod);
833
834/**
835 * Adds a symbol to the list of global symbols that must exist in the final
836 * generated code. If a function is not listed there, it might be inlined into
837 * every usage and optimized away. For every single module, the functions
838 * referenced from code outside of the ThinLTO modules need to be added here.
839 *
840 * \since LTO_API_VERSION=18
841 */
842extern void thinlto_codegen_add_must_preserve_symbol(thinlto_code_gen_t cg,
843 const char *name,
844 int length);
845
846/**
847 * Adds a symbol to the list of global symbols that are cross-referenced between
848 * ThinLTO files. If the ThinLTO CodeGenerator can ensure that every
849 * references from a ThinLTO module to this symbol is optimized away, then
850 * the symbol can be discarded.
851 *
852 * \since LTO_API_VERSION=18
853 */
854extern void thinlto_codegen_add_cross_referenced_symbol(thinlto_code_gen_t cg,
855 const char *name,
856 int length);
857
858/**
859 * @} // endgoup LLVMCTLTO
860 * @defgroup LLVMCTLTO_CACHING ThinLTO Cache Control
861 * @ingroup LLVMCTLTO
862 *
863 * These entry points control the ThinLTO cache. The cache is intended to
864 * support incremental builds, and thus needs to be persistent across builds.
865 * The client enables the cache by supplying a path to an existing directory.
866 * The code generator will use this to store objects files that may be reused
867 * during a subsequent build.
868 * To avoid filling the disk space, a few knobs are provided:
869 * - The pruning interval limits the frequency at which the garbage collector
870 * will try to scan the cache directory to prune expired entries.
871 * Setting to a negative number disables the pruning.
872 * - The pruning expiration time indicates to the garbage collector how old an
873 * entry needs to be to be removed.
874 * - Finally, the garbage collector can be instructed to prune the cache until
875 * the occupied space goes below a threshold.
876 * @{
877 */
878
879/**
880 * Sets the path to a directory to use as a cache storage for incremental build.
881 * Setting this activates caching.
882 *
883 * \since LTO_API_VERSION=18
884 */
885extern void thinlto_codegen_set_cache_dir(thinlto_code_gen_t cg,
886 const char *cache_dir);
887
888/**
889 * Sets the cache pruning interval (in seconds). A negative value disables the
890 * pruning. An unspecified default value will be applied, and a value of 0 will
891 * force prunning to occur.
892 *
893 * \since LTO_API_VERSION=18
894 */
895extern void thinlto_codegen_set_cache_pruning_interval(thinlto_code_gen_t cg,
896 int interval);
897
898/**
899 * Sets the maximum cache size that can be persistent across build, in terms of
900 * percentage of the available space on the disk. Set to 100 to indicate
901 * no limit, 50 to indicate that the cache size will not be left over half the
902 * available space. A value over 100 will be reduced to 100, a value of 0 will
903 * be ignored. An unspecified default value will be applied.
904 *
905 * The formula looks like:
906 * AvailableSpace = FreeSpace + ExistingCacheSize
907 * NewCacheSize = AvailableSpace * P/100
908 *
909 * \since LTO_API_VERSION=18
910 */
911extern void thinlto_codegen_set_final_cache_size_relative_to_available_space(
912 thinlto_code_gen_t cg, unsigned percentage);
913
914/**
915 * Sets the expiration (in seconds) for an entry in the cache. An unspecified
916 * default value will be applied. A value of 0 will be ignored.
917 *
918 * \since LTO_API_VERSION=18
919 */
920extern void thinlto_codegen_set_cache_entry_expiration(thinlto_code_gen_t cg,
921 unsigned expiration);
922
923/**
924 * Sets the maximum size of the cache directory (in bytes). A value over the
925 * amount of available space on the disk will be reduced to the amount of
926 * available space. An unspecified default value will be applied. A value of 0
927 * will be ignored.
928 *
929 * \since LTO_API_VERSION=22
930 */
931extern void thinlto_codegen_set_cache_size_bytes(thinlto_code_gen_t cg,
932 unsigned max_size_bytes);
933
934/**
935 * Same as thinlto_codegen_set_cache_size_bytes, except the maximum size is in
936 * megabytes (2^20 bytes).
937 *
938 * \since LTO_API_VERSION=23
939 */
940extern void
941thinlto_codegen_set_cache_size_megabytes(thinlto_code_gen_t cg,
942 unsigned max_size_megabytes);
943
944/**
945 * Sets the maximum number of files in the cache directory. An unspecified
946 * default value will be applied. A value of 0 will be ignored.
947 *
948 * \since LTO_API_VERSION=22
949 */
950extern void thinlto_codegen_set_cache_size_files(thinlto_code_gen_t cg,
951 unsigned max_size_files);
952
953/**
954 * @} // endgroup LLVMCTLTO_CACHING
955 */
956
957LLVM_C_EXTERN_C_END
958
959#endif /* LLVM_C_LTO_H */
960