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376 * Upon return the lto_code_gen_t is no longer valid.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