1 /*===-- llvm-c/lto.h - LTO Public C Interface ---------------------*- C -*-===*\
3 |* The LLVM Compiler Infrastructure *|
5 |* This file is distributed under the University of Illinois Open Source *|
6 |* License. See LICENSE.TXT for details. *|
8 |*===----------------------------------------------------------------------===*|
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. *|
14 \*===----------------------------------------------------------------------===*/
24 #include <sys/types.h>
27 #if !defined(_MSC_VER)
29 typedef bool lto_bool_t;
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
34 typedef unsigned char lto_bool_t;
37 typedef bool lto_bool_t;
41 * @defgroup LLVMCLTO LTO
47 #define LTO_API_VERSION 21
50 * \since prior to LTO_API_VERSION=3
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;
75 * \since prior to LTO_API_VERSION=3
78 LTO_DEBUG_MODEL_NONE = 0,
79 LTO_DEBUG_MODEL_DWARF = 1
83 * \since prior to LTO_API_VERSION=3
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
92 /** opaque reference to a loaded object module */
93 typedef struct LLVMOpaqueLTOModule *lto_module_t;
95 /** opaque reference to a code generator */
96 typedef struct LLVMOpaqueLTOCodeGenerator *lto_code_gen_t;
98 /** opaque reference to a thin code generator */
99 typedef struct LLVMOpaqueThinLTOCodeGenerator *thinlto_code_gen_t;
106 * Returns a printable string.
108 * \since prior to LTO_API_VERSION=3
111 lto_get_version(void);
114 * Returns the last error string or NULL if last operation was successful.
116 * \since prior to LTO_API_VERSION=3
119 lto_get_error_message(void);
122 * Checks if a file is a loadable object file.
124 * \since prior to LTO_API_VERSION=3
127 lto_module_is_object_file(const char* path);
130 * Checks if a file is a loadable object compiled for requested target.
132 * \since prior to LTO_API_VERSION=3
135 lto_module_is_object_file_for_target(const char* path,
136 const char* target_triple_prefix);
139 * Return true if \p Buffer contains a bitcode file with ObjC code (category
142 * \since LTO_API_VERSION=20
145 lto_module_has_objc_category(const void *mem, size_t length);
148 * Checks if a buffer is a loadable object file.
150 * \since prior to LTO_API_VERSION=3
152 extern lto_bool_t lto_module_is_object_file_in_memory(const void *mem,
156 * Checks if a buffer is a loadable object compiled for requested target.
158 * \since prior to LTO_API_VERSION=3
161 lto_module_is_object_file_in_memory_for_target(const void* mem, size_t length,
162 const char* target_triple_prefix);
165 * Loads an object file from disk.
166 * Returns NULL on error (check lto_get_error_message() for details).
168 * \since prior to LTO_API_VERSION=3
171 lto_module_create(const char* path);
174 * Loads an object file from memory.
175 * Returns NULL on error (check lto_get_error_message() for details).
177 * \since prior to LTO_API_VERSION=3
180 lto_module_create_from_memory(const void* mem, size_t length);
183 * Loads an object file from memory with an extra path argument.
184 * Returns NULL on error (check lto_get_error_message() for details).
186 * \since LTO_API_VERSION=9
189 lto_module_create_from_memory_with_path(const void* mem, size_t length,
193 * \brief Loads an object file in its own context.
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().
199 * Returns NULL on error (check lto_get_error_message() for details).
201 * \since LTO_API_VERSION=11
204 lto_module_create_in_local_context(const void *mem, size_t length,
208 * \brief Loads an object file in the codegen context.
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().
213 * Returns NULL on error (check lto_get_error_message() for details).
215 * \since LTO_API_VERSION=11
218 lto_module_create_in_codegen_context(const void *mem, size_t length,
219 const char *path, lto_code_gen_t cg);
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).
225 * \since LTO_API_VERSION=5
228 lto_module_create_from_fd(int fd, const char *path, size_t file_size);
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).
234 * \since LTO_API_VERSION=5
237 lto_module_create_from_fd_at_offset(int fd, const char *path, size_t file_size,
238 size_t map_size, off_t offset);
241 * Frees all memory internally allocated by the module.
242 * Upon return the lto_module_t is no longer valid.
244 * \since prior to LTO_API_VERSION=3
247 lto_module_dispose(lto_module_t mod);
250 * Returns triple string which the object module was compiled under.
252 * \since prior to LTO_API_VERSION=3
255 lto_module_get_target_triple(lto_module_t mod);
258 * Sets triple string with which the object will be codegened.
260 * \since LTO_API_VERSION=4
263 lto_module_set_target_triple(lto_module_t mod, const char *triple);
266 * Returns the number of symbols in the object module.
268 * \since prior to LTO_API_VERSION=3
271 lto_module_get_num_symbols(lto_module_t mod);
274 * Returns the name of the ith symbol in the object module.
276 * \since prior to LTO_API_VERSION=3
279 lto_module_get_symbol_name(lto_module_t mod, unsigned int index);
282 * Returns the attributes of the ith symbol in the object module.
284 * \since prior to LTO_API_VERSION=3
286 extern lto_symbol_attributes
287 lto_module_get_symbol_attribute(lto_module_t mod, unsigned int index);
290 * Returns the module's linker options.
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.
295 * \since LTO_API_VERSION=16
298 lto_module_get_linkeropts(lto_module_t mod);
301 * Diagnostic severity.
303 * \since LTO_API_VERSION=7
308 LTO_DS_REMARK = 3, // Added in LTO_API_VERSION=10.
310 } lto_codegen_diagnostic_severity_t;
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.
319 * \since LTO_API_VERSION=7
321 typedef void (*lto_diagnostic_handler_t)(
322 lto_codegen_diagnostic_severity_t severity, const char *diag, void *ctxt);
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.
329 * \since LTO_API_VERSION=7
331 extern void lto_codegen_set_diagnostic_handler(lto_code_gen_t,
332 lto_diagnostic_handler_t,
336 * Instantiates a code generator.
337 * Returns NULL on error (check lto_get_error_message() for details).
339 * All modules added using \a lto_codegen_add_module() must have been created
340 * in the same context as the codegen.
342 * \since prior to LTO_API_VERSION=3
344 extern lto_code_gen_t
345 lto_codegen_create(void);
348 * \brief Instantiate a code generator in its own context.
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().
354 * \since LTO_API_VERSION=11
356 extern lto_code_gen_t
357 lto_codegen_create_in_local_context(void);
360 * Frees all code generator and all memory it internally allocated.
361 * Upon return the lto_code_gen_t is no longer valid.
363 * \since prior to LTO_API_VERSION=3
366 lto_codegen_dispose(lto_code_gen_t);
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).
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().
376 * \since prior to LTO_API_VERSION=3
379 lto_codegen_add_module(lto_code_gen_t cg, lto_module_t mod);
382 * Sets the object module for code generation. This will transfer the ownership
383 * of the module to the code generator.
385 * \c cg and \c mod must both be in the same context.
387 * \since LTO_API_VERSION=13
390 lto_codegen_set_module(lto_code_gen_t cg, lto_module_t mod);
393 * Sets if debug info should be generated.
394 * Returns true on error (check lto_get_error_message() for details).
396 * \since prior to LTO_API_VERSION=3
399 lto_codegen_set_debug_model(lto_code_gen_t cg, lto_debug_model);
402 * Sets which PIC code model to generated.
403 * Returns true on error (check lto_get_error_message() for details).
405 * \since prior to LTO_API_VERSION=3
408 lto_codegen_set_pic_model(lto_code_gen_t cg, lto_codegen_model);
411 * Sets the cpu to generate code for.
413 * \since LTO_API_VERSION=4
416 lto_codegen_set_cpu(lto_code_gen_t cg, const char *cpu);
419 * Sets the location of the assembler tool to run. If not set, libLTO
420 * will use gcc to invoke the assembler.
422 * \since LTO_API_VERSION=3
425 lto_codegen_set_assembler_path(lto_code_gen_t cg, const char* path);
428 * Sets extra arguments that libLTO should pass to the assembler.
430 * \since LTO_API_VERSION=4
433 lto_codegen_set_assembler_args(lto_code_gen_t cg, const char **args,
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.
441 * \since prior to LTO_API_VERSION=3
444 lto_codegen_add_must_preserve_symbol(lto_code_gen_t cg, const char* symbol);
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).
451 * \since LTO_API_VERSION=5
454 lto_codegen_write_merged_modules(lto_code_gen_t cg, const char* path);
457 * Generates code for all added modules into one native object file.
458 * This calls lto_codegen_optimize then lto_codegen_compile_optimized.
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).
466 * \since prior to LTO_API_VERSION=3
469 lto_codegen_compile(lto_code_gen_t cg, size_t* length);
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).
476 * The name of the file is written to name. Returns true on error.
478 * \since LTO_API_VERSION=5
481 lto_codegen_compile_to_file(lto_code_gen_t cg, const char** name);
484 * Runs optimization for the merged module. Returns true on error.
486 * \since LTO_API_VERSION=12
489 lto_codegen_optimize(lto_code_gen_t cg);
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.
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).
501 * \since LTO_API_VERSION=12
504 lto_codegen_compile_optimized(lto_code_gen_t cg, size_t* length);
507 * Returns the runtime API version.
509 * \since LTO_API_VERSION=12
512 lto_api_version(void);
515 * Sets options to help debug codegen bugs.
517 * \since prior to LTO_API_VERSION=3
520 lto_codegen_debug_options(lto_code_gen_t cg, const char *);
523 * Initializes LLVM disassemblers.
524 * FIXME: This doesn't really belong here.
526 * \since LTO_API_VERSION=5
529 lto_initialize_disassembler(void);
532 * Sets if we should run internalize pass during optimization and code
535 * \since LTO_API_VERSION=14
538 lto_codegen_set_should_internalize(lto_code_gen_t cg,
539 lto_bool_t ShouldInternalize);
542 * \brief Set whether to embed uselists in bitcode.
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.
547 * \since LTO_API_VERSION=15
550 lto_codegen_set_should_embed_uselists(lto_code_gen_t cg,
551 lto_bool_t ShouldEmbedUselists);
555 * @defgroup LLVMCTLTO ThinLTO
562 * Type to wrap a single object returned by ThinLTO.
564 * \since LTO_API_VERSION=18
572 * Instantiates a ThinLTO code generator.
573 * Returns NULL on error (check lto_get_error_message() for details).
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
581 * \since LTO_API_VERSION=18
583 extern thinlto_code_gen_t thinlto_create_codegen(void);
586 * Frees the generator and all memory it internally allocated.
587 * Upon return the thinlto_code_gen_t is no longer valid.
589 * \since LTO_API_VERSION=18
591 extern void thinlto_codegen_dispose(thinlto_code_gen_t cg);
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.
599 * On failure, returns NULL (check lto_get_error_message() for details).
602 * \since LTO_API_VERSION=18
604 extern void thinlto_codegen_add_module(thinlto_code_gen_t cg,
605 const char *identifier, const char *data,
609 * Optimize and codegen all the modules added to the codegenerator using
610 * ThinLTO. Resulting objects are accessible using thinlto_module_get_object().
612 * \since LTO_API_VERSION=18
614 extern void thinlto_codegen_process(thinlto_code_gen_t cg);
617 * Returns the number of object files produced by the ThinLTO CodeGenerator.
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
623 * \since LTO_API_VERSION=18
625 extern unsigned int thinlto_module_get_num_objects(thinlto_code_gen_t cg);
628 * Returns a reference to the ith object file produced by the ThinLTO
631 * Client should use \p thinlto_module_get_num_objects() to get the number of
634 * \since LTO_API_VERSION=18
636 extern LTOObjectBuffer thinlto_module_get_object(thinlto_code_gen_t cg,
640 * Returns the number of object files produced by the ThinLTO CodeGenerator.
642 * It usually matches the number of input files, but this is not a guarantee of
643 * the API and may change in future implementation, so the client should not
646 * \since LTO_API_VERSION=21
648 unsigned int thinlto_module_get_num_object_files(thinlto_code_gen_t cg);
651 * Returns the path to the ith object file produced by the ThinLTO
654 * Client should use \p thinlto_module_get_num_object_files() to get the number
655 * of available objects.
657 * \since LTO_API_VERSION=21
659 const char *thinlto_module_get_object_file(thinlto_code_gen_t cg,
663 * Sets which PIC code model to generate.
664 * Returns true on error (check lto_get_error_message() for details).
666 * \since LTO_API_VERSION=18
668 extern lto_bool_t thinlto_codegen_set_pic_model(thinlto_code_gen_t cg,
673 * @defgroup LLVMCTLTO_CACHING ThinLTO Cache Control
676 * These entry points control the ThinLTO cache. The cache is intended to
677 * support incremental build, and thus needs to be persistent accross build.
678 * The client enabled the cache by supplying a path to an existing directory.
679 * The code generator will use this to store objects files that may be reused
680 * during a subsequent build.
681 * To avoid filling the disk space, a few knobs are provided:
682 * - The pruning interval limit the frequency at which the garbage collector
683 * will try to scan the cache directory to prune it from expired entries.
684 * Setting to -1 disable the pruning (default).
685 * - The pruning expiration time indicates to the garbage collector how old an
686 * entry needs to be to be removed.
687 * - Finally, the garbage collector can be instructed to prune the cache till
688 * the occupied space goes below a threshold.
693 * Sets the path to a directory to use as a cache storage for incremental build.
694 * Setting this activates caching.
696 * \since LTO_API_VERSION=18
698 extern void thinlto_codegen_set_cache_dir(thinlto_code_gen_t cg,
699 const char *cache_dir);
702 * Sets the cache pruning interval (in seconds). A negative value disable the
703 * pruning. An unspecified default value will be applied, and a value of 0 will
706 * \since LTO_API_VERSION=18
708 extern void thinlto_codegen_set_cache_pruning_interval(thinlto_code_gen_t cg,
712 * Sets the maximum cache size that can be persistent across build, in terms of
713 * percentage of the available space on the the disk. Set to 100 to indicate
714 * no limit, 50 to indicate that the cache size will not be left over half the
715 * available space. A value over 100 will be reduced to 100, a value of 0 will
716 * be ignored. An unspecified default value will be applied.
718 * The formula looks like:
719 * AvailableSpace = FreeSpace + ExistingCacheSize
720 * NewCacheSize = AvailableSpace * P/100
722 * \since LTO_API_VERSION=18
724 extern void thinlto_codegen_set_final_cache_size_relative_to_available_space(
725 thinlto_code_gen_t cg, unsigned percentage);
728 * Sets the expiration (in seconds) for an entry in the cache. An unspecified
729 * default value will be applied. A value of 0 will be ignored.
731 * \since LTO_API_VERSION=18
733 extern void thinlto_codegen_set_cache_entry_expiration(thinlto_code_gen_t cg,
734 unsigned expiration);
741 * Sets the path to a directory to use as a storage for temporary bitcode files.
742 * The intention is to make the bitcode files available for debugging at various
743 * stage of the pipeline.
745 * \since LTO_API_VERSION=18
747 extern void thinlto_codegen_set_savetemps_dir(thinlto_code_gen_t cg,
748 const char *save_temps_dir);
751 * Set the path to a directory where to save generated object files. This
752 * path can be used by a linker to request on-disk files instead of in-memory
753 * buffers. When set, results are available through
754 * thinlto_module_get_object_file() instead of thinlto_module_get_object().
756 * \since LTO_API_VERSION=21
758 void thinlto_set_generated_objects_dir(thinlto_code_gen_t cg,
759 const char *save_temps_dir);
762 * Sets the cpu to generate code for.
764 * \since LTO_API_VERSION=18
766 extern void thinlto_codegen_set_cpu(thinlto_code_gen_t cg, const char *cpu);
769 * Disable CodeGen, only run the stages till codegen and stop. The output will
772 * \since LTO_API_VERSION=19
774 extern void thinlto_codegen_disable_codegen(thinlto_code_gen_t cg,
778 * Perform CodeGen only: disable all other stages.
780 * \since LTO_API_VERSION=19
782 extern void thinlto_codegen_set_codegen_only(thinlto_code_gen_t cg,
783 lto_bool_t codegen_only);
786 * Parse -mllvm style debug options.
788 * \since LTO_API_VERSION=18
790 extern void thinlto_debug_options(const char *const *options, int number);
793 * Test if a module has support for ThinLTO linking.
795 * \since LTO_API_VERSION=18
797 extern lto_bool_t lto_module_is_thinlto(lto_module_t mod);
800 * Adds a symbol to the list of global symbols that must exist in the final
801 * generated code. If a function is not listed there, it might be inlined into
802 * every usage and optimized away. For every single module, the functions
803 * referenced from code outside of the ThinLTO modules need to be added here.
805 * \since LTO_API_VERSION=18
807 extern void thinlto_codegen_add_must_preserve_symbol(thinlto_code_gen_t cg,
812 * Adds a symbol to the list of global symbols that are cross-referenced between
813 * ThinLTO files. If the ThinLTO CodeGenerator can ensure that every
814 * references from a ThinLTO module to this symbol is optimized away, then
815 * the symbol can be discarded.
817 * \since LTO_API_VERSION=18
819 extern void thinlto_codegen_add_cross_referenced_symbol(thinlto_code_gen_t cg,
831 #endif /* LLVM_C_LTO_H */