llvm/include/llvm-c/lto.h

   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>
  31 typedef 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. */
  36 typedef unsigned char lto_bool_t;
  37 #endif
  38 #else
  39 typedef 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  */
  54 typedef 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  */
  79 typedef 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  */
  87 typedef 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 */
  95 typedef struct LLVMOpaqueLTOModule *lto_module_t;
  96
  97 /** opaque reference to a code generator */
  98 typedef struct LLVMOpaqueLTOCodeGenerator *lto_code_gen_t;
  99
 100 /** opaque reference to a thin code generator */
 101 typedef struct LLVMOpaqueThinLTOCodeGenerator *thinlto_code_gen_t;
 102
 103 LLVM_C_EXTERN_C_BEGIN
 104
 105 /**
 106  * Returns a printable string.
 107  *
 108  * \since prior to LTO_API_VERSION=3
 109  */
 110 extern const char*
 111 lto_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  */
 118 extern const char*
 119 lto_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  */
 126 extern lto_bool_t
 127 lto_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  */
 134 extern lto_bool_t
 135 lto_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  */
 144 extern lto_bool_t
 145 lto_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  */
 152 extern 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  */
 160 extern lto_bool_t
 161 lto_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  */
 170 extern lto_module_t
 171 lto_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  */
 179 extern lto_module_t
 180 lto_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  */
 188 extern lto_module_t
 189 lto_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  */
 203 extern lto_module_t
 204 lto_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  */
 217 extern lto_module_t
 218 lto_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  */
 227 extern lto_module_t
 228 lto_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  */
 236 extern lto_module_t
 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);
 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  */
 246 extern void
 247 lto_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  */
 254 extern const char*
 255 lto_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  */
 262 extern void
 263 lto_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  */
 270 extern unsigned int
 271 lto_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  */
 278 extern const char*
 279 lto_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  */
 286 extern lto_symbol_attributes
 287 lto_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  */
 297 extern const char*
 298 lto_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  */
 311 extern 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  */
 324 extern lto_bool_t lto_module_has_ctor_dtor(lto_module_t mod);
 325 /**
 326  * Diagnostic severity.
 327  *
 328  * \since LTO_API_VERSION=7
 329  */
 330 typedef 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  */
 346 typedef 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  */
 356 extern 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  */
 369 extern lto_code_gen_t
 370 lto_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  */
 381 extern lto_code_gen_t
 382 lto_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  */
 390 extern void
 391 lto_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  */
 403 extern lto_bool_t
 404 lto_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  */
 414 extern void
 415 lto_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  */
 423 extern lto_bool_t
 424 lto_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  */
 432 extern lto_bool_t
 433 lto_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  */
 440 extern void
 441 lto_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  */
 449 extern void
 450 lto_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  */
 457 extern void
 458 lto_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  */
 468 extern void
 469 lto_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  */
 478 extern lto_bool_t
 479 lto_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  */
 493 extern const void*
 494 lto_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  */
 505 extern lto_bool_t
 506 lto_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  */
 513 extern lto_bool_t
 514 lto_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  */
 528 extern const void*
 529 lto_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  */
 536 extern unsigned int
 537 lto_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  */
 551 extern 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  */
 564 extern void
 565 lto_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  */
 573 extern 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  */
 582 extern void
 583 lto_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  */
 591 extern void
 592 lto_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  */
 603 extern void
 604 lto_codegen_set_should_embed_uselists(lto_code_gen_t cg,
 605                                       lto_bool_t ShouldEmbedUselists);
 606
 607 /** Opaque reference to an LTO input file */
 608 typedef 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   */
 618 extern 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   */
 628 extern 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   */
 636 extern 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   */
 645 extern 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  */
 655 extern 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  */
 670 typedef 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  */
 687 extern 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  */
 695 extern 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  */
 708 extern 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  */
 718 extern 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  */
 729 extern 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  */
 740 extern 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  */
 752 unsigned 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  */
 763 const 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  */
 772 extern 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  */
 782 extern 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  */
 793 void 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  */
 801 extern 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  */
 809 extern 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  */
 817 extern 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  */
 825 extern 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  */
 832 extern 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  */
 842 extern 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  */
 854 extern 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  */
 885 extern 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  */
 895 extern 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  */
 911 extern 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  */
 920 extern 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  */
 931 extern 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  */
 940 extern void
 941 thinlto_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  */
 950 extern 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
 957 LLVM_C_EXTERN_C_END
 958
 959 #endif /* LLVM_C_LTO_H */