gcc/flags.h

   1 /* Compilation switch flag definitions for GCC.
   2    Copyright (C) 1987, 1988, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2002,
   3    2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   4    Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef GCC_FLAGS_H
  23 #define GCC_FLAGS_H
  24
  25 #include "coretypes.h"
  26 #include "options.h"
  27
  28 enum debug_info_type
  29 {
  30   NO_DEBUG,         /* Write no debug info.  */
  31   DBX_DEBUG,        /* Write BSD .stabs for DBX (using dbxout.c).  */
  32   SDB_DEBUG,        /* Write COFF for (old) SDB (using sdbout.c).  */
  33   DWARF2_DEBUG,     /* Write Dwarf v2 debug info (using dwarf2out.c).  */
  34   XCOFF_DEBUG,      /* Write IBM/Xcoff debug info (using dbxout.c).  */
  35   VMS_DEBUG,        /* Write VMS debug info (using vmsdbgout.c).  */
  36   VMS_AND_DWARF2_DEBUG /* Write VMS debug info (using vmsdbgout.c).
  37                           and DWARF v2 debug info (using dwarf2out.c).  */
  38 };
  39
  40 /* Specify which kind of debugging info to generate.  */
  41 extern enum debug_info_type write_symbols;
  42
  43 /* Names of debug_info_type, for error messages.  */
  44 extern const char *const debug_type_names[];
  45
  46 enum debug_info_level
  47 {
  48   DINFO_LEVEL_NONE,     /* Write no debugging info.  */
  49   DINFO_LEVEL_TERSE,    /* Write minimal info to support tracebacks only.  */
  50   DINFO_LEVEL_NORMAL,   /* Write info for all declarations (and line table).  */
  51   DINFO_LEVEL_VERBOSE   /* Write normal info plus #define/#undef info.  */
  52 };
  53
  54 /* Specify how much debugging info to generate.  */
  55 extern enum debug_info_level debug_info_level;
  56
  57 /* A major contribution to object and executable size is debug
  58    information size.  A major contribution to debug information
  59    size is struct descriptions replicated in several object files.
  60    The following function determines whether or not debug information
  61    should be generated for a given struct.  The indirect parameter
  62    indicates that the struct is being handled indirectly, via
  63    a pointer.  See opts.c for the implementation. */
  64
  65 enum debug_info_usage
  66 {
  67   DINFO_USAGE_DFN,      /* A struct definition. */
  68   DINFO_USAGE_DIR_USE,  /* A direct use, such as the type of a variable. */
  69   DINFO_USAGE_IND_USE,  /* An indirect use, such as through a pointer. */
  70   DINFO_USAGE_NUM_ENUMS /* The number of enumerators. */
  71 };
  72
  73 extern bool should_emit_struct_debug (tree type_decl, enum debug_info_usage);
  74 extern void set_struct_debug_option (const char *value);
  75
  76 /* Nonzero means use GNU-only extensions in the generated symbolic
  77    debugging information.  */
  78 extern bool use_gnu_debug_info_extensions;
  79
  80 /* Enumerate visibility settings.  This is deliberately ordered from most
  81    to least visibility.  */
  82 #ifndef SYMBOL_VISIBILITY_DEFINED
  83 #define SYMBOL_VISIBILITY_DEFINED
  84 enum symbol_visibility
  85 {
  86   VISIBILITY_DEFAULT,
  87   VISIBILITY_PROTECTED,
  88   VISIBILITY_HIDDEN,
  89   VISIBILITY_INTERNAL
  90 };
  91 #endif
  92
  93 /* The default visibility for all symbols (unless overridden).  */
  94 extern enum symbol_visibility default_visibility;
  95
  96 struct visibility_flags
  97 {
  98   unsigned inpragma : 1;        /* True when in #pragma GCC visibility.  */
  99   unsigned inlines_hidden : 1;  /* True when -finlineshidden in effect.  */
 100 };
 101
 102 /* Global visibility options.  */
 103 extern struct visibility_flags visibility_options;
 104
 105 /* Nonzero means do optimizations.  -opt.  */
 106
 107 extern int optimize;
 108
 109 /* Nonzero means optimize for size.  -Os.  */
 110
 111 extern int optimize_size;
 112
 113 /* True if this is the LTO front end (lto1).  This is used to disable
 114    gimple generation and lowering passes that are normally run on the
 115    output of a front end.  These passes must be bypassed for lto since
 116    they have already been done before the gimple was written.  */
 117
 118 extern bool in_lto_p;
 119
 120 /* Nonzero if we should write GIMPLE bytecode for link-time optimization.  */
 121
 122 extern int flag_generate_lto;
 123
 124 /* Used to set the level of -Wstrict-aliasing, when no level is specified.
 125    The external way to set the default level is to use
 126    -Wstrict-aliasing=level.
 127    ONOFF is assumed to take value 1 when -Wstrict-aliasing is specified,
 128    and 0 otherwise.  After calling this function, wstrict_aliasing will be
 129    set to the default value of -Wstrict_aliasing=level.  */
 130
 131 extern void set_Wstrict_aliasing (int onoff);
 132
 133 /* Nonzero means warn about any objects definitions whose size is larger
 134    than N bytes.  Also want about function definitions whose returned
 135    values are larger than N bytes. The value N is in `larger_than_size'.  */
 136
 137 extern bool warn_larger_than;
 138 extern HOST_WIDE_INT larger_than_size;
 139
 140 /* Nonzero means warn about any function whose frame size is larger
 141    than N bytes. */
 142
 143 extern bool warn_frame_larger_than;
 144 extern HOST_WIDE_INT frame_larger_than_size;
 145
 146 /* Nonzero for -dp: annotate the assembly with a comment describing the
 147    pattern and alternative used.  */
 148
 149 extern int flag_print_asm_name;
 150 \f
 151 /* Now the symbols that are set with `-f' switches.  */
 152
 153 /* Nonzero means `char' should be signed.  */
 154
 155 extern int flag_signed_char;
 156
 157 /* Nonzero means give an enum type only as many bytes as it needs.  A value
 158    of 2 means it has not yet been initialized.  */
 159
 160 extern int flag_short_enums;
 161
 162 /* Nonzero for -fpcc-struct-return: return values the same way PCC does.  */
 163
 164 extern int flag_pcc_struct_return;
 165
 166 /* 0 means straightforward implementation of complex divide acceptable.
 167    1 means wide ranges of inputs must work for complex divide.
 168    2 means C99-like requirements for complex multiply and divide.  */
 169
 170 extern int flag_complex_method;
 171
 172 /* Nonzero if we are only using compiler to check syntax errors.  */
 173
 174 extern int rtl_dump_and_exit;
 175
 176 /* Nonzero means we should save auxiliary info into a .X file.  */
 177
 178 extern int flag_gen_aux_info;
 179
 180 /* Nonzero means suppress output of instruction numbers and line number
 181    notes in debugging dumps.  */
 182
 183 extern int flag_dump_unnumbered;
 184
 185 /* True if printing into -fdump-final-insns= dump.  */
 186
 187 extern bool final_insns_dump_p;
 188
 189 /* Nonzero means change certain warnings into errors.
 190    Usually these are warnings about failure to conform to some standard.  */
 191
 192 extern int flag_pedantic_errors;
 193
 194 /* Nonzero means make permerror produce warnings instead of errors.  */
 195
 196 extern int flag_permissive;
 197
 198 /* Nonzero if we are compiling code for a shared library, zero for
 199    executable.  */
 200
 201 extern int flag_shlib;
 202
 203 /* -dA causes debug information to be produced in
 204    the generated assembly code (to make it more readable).  This option
 205    is generally only of use to those who actually need to read the
 206    generated assembly code (perhaps while debugging the compiler itself).
 207    Currently, this switch is only used by dwarfout.c; however, it is intended
 208    to be a catchall for printing debug information in the assembler file.  */
 209
 210 extern int flag_debug_asm;
 211
 212 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 213
 214 extern int flag_next_runtime;
 215
 216 extern int flag_dump_rtl_in_asm;
 217
 218 /* The algorithm used for the integrated register allocator (IRA).  */
 219 enum ira_algorithm
 220 {
 221   IRA_ALGORITHM_CB,
 222   IRA_ALGORITHM_PRIORITY
 223 };
 224
 225 extern enum ira_algorithm flag_ira_algorithm;
 226
 227 /* The regions used for the integrated register allocator (IRA).  */
 228 enum ira_region
 229 {
 230   IRA_REGION_ONE,
 231   IRA_REGION_ALL,
 232   IRA_REGION_MIXED
 233 };
 234
 235 extern enum ira_region flag_ira_region;
 236
 237 extern unsigned int flag_ira_verbose;
 238
 239 /* The options for excess precision.  */
 240 enum excess_precision
 241 {
 242   EXCESS_PRECISION_DEFAULT,
 243   EXCESS_PRECISION_FAST,
 244   EXCESS_PRECISION_STANDARD
 245 };
 246
 247 /* The excess precision specified on the command line, or defaulted by
 248    the front end.  */
 249 extern enum excess_precision flag_excess_precision_cmdline;
 250
 251 /* The excess precision currently in effect.  */
 252 extern enum excess_precision flag_excess_precision;
 253
 254 \f
 255 /* Other basic status info about current function.  */
 256
 257 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 258 extern int flag_evaluation_order;
 259
 260 /* Value of the -G xx switch, and whether it was passed or not.  */
 261 extern unsigned HOST_WIDE_INT g_switch_value;
 262 extern bool g_switch_set;
 263
 264 /* Same for selective scheduling.  */
 265 extern bool sel_sched_switch_set;
 266
 267 /* Whether to run the warn_unused_result attribute pass.  */
 268 extern bool flag_warn_unused_result;
 269
 270 /* Values of the -falign-* flags: how much to align labels in code.
 271    0 means `use default', 1 means `don't align'.
 272    For each variable, there is an _log variant which is the power
 273    of two not less than the variable, for .align output.  */
 274
 275 extern int align_loops_log;
 276 extern int align_loops_max_skip;
 277 extern int align_jumps_log;
 278 extern int align_jumps_max_skip;
 279 extern int align_labels_log;
 280 extern int align_labels_max_skip;
 281 extern int align_functions_log;
 282
 283 /* Nonzero if we dump in VCG format, not plain text.  */
 284 extern int dump_for_graph;
 285
 286 /* Selection of the graph form.  */
 287 enum graph_dump_types
 288 {
 289   no_graph = 0,
 290   vcg
 291 };
 292 extern enum graph_dump_types graph_dump_format;
 293
 294 /* Nonzero means to collect statistics which might be expensive
 295    and to print them when we are done.  */
 296 extern int flag_detailed_statistics;
 297
 298 /* Nonzero means that we defer emitting functions until they are actually
 299    used.  */
 300 extern int flag_remove_unreachable_functions;
 301
 302 /* Nonzero if we should track variables.  */
 303 extern int flag_var_tracking;
 304
 305 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 306    warning message in case flag was set by -fprofile-{generate,use}.  */
 307 extern bool flag_speculative_prefetching_set;
 308
 309 /* Type of stack check.  */
 310 enum stack_check_type
 311 {
 312   /* Do not check the stack.  */
 313   NO_STACK_CHECK = 0,
 314
 315   /* Check the stack generically, i.e. assume no specific support
 316      from the target configuration files.  */
 317   GENERIC_STACK_CHECK,
 318
 319   /* Check the stack and rely on the target configuration files to
 320      check the static frame of functions, i.e. use the generic
 321      mechanism only for dynamic stack allocations.  */
 322   STATIC_BUILTIN_STACK_CHECK,
 323
 324   /* Check the stack and entirely rely on the target configuration
 325      files, i.e. do not use the generic mechanism at all.  */
 326   FULL_BUILTIN_STACK_CHECK
 327 };
 328 extern enum stack_check_type flag_stack_check;
 329
 330 /* Returns TRUE if generated code should match ABI version N or
 331    greater is in use.  */
 332
 333 #define abi_version_at_least(N) \
 334   (flag_abi_version == 0 || flag_abi_version >= (N))
 335
 336 /* Return whether the function should be excluded from
 337    instrumentation.  */
 338 extern bool flag_instrument_functions_exclude_p (tree fndecl);
 339
 340 /* True if overflow wraps around for the given integral type.  That
 341    is, TYPE_MAX + 1 == TYPE_MIN.  */
 342 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 343   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 344
 345 /* True if overflow is undefined for the given integral type.  We may
 346    optimize on the assumption that values in the type never overflow.
 347
 348    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 349    must issue a warning based on warn_strict_overflow.  In some cases
 350    it will be appropriate to issue the warning immediately, and in
 351    other cases it will be appropriate to simply set a flag and let the
 352    caller decide whether a warning is appropriate or not.  */
 353 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 354   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 355
 356 /* True if overflow for the given integral type should issue a
 357    trap.  */
 358 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 359   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 360
 361 /* True if pointer types have undefined overflow.  */
 362 #define POINTER_TYPE_OVERFLOW_UNDEFINED (flag_strict_overflow)
 363
 364 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 365    values here correspond to N.  */
 366
 367 enum warn_strict_overflow_code
 368 {
 369   /* Overflow warning that should be issued with -Wall: a questionable
 370      construct that is easy to avoid even when using macros.  Example:
 371      folding (x + CONSTANT > x) to 1.  */
 372   WARN_STRICT_OVERFLOW_ALL = 1,
 373   /* Overflow warning about folding a comparison to a constant because
 374      of undefined signed overflow, other than cases covered by
 375      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 376      (this is false when x == INT_MIN).  */
 377   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 378   /* Overflow warning about changes to comparisons other than folding
 379      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 380   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 381   /* Overflow warnings not covered by the above cases.  Example:
 382      folding ((x * 10) / 5) to (x * 2).  */
 383   WARN_STRICT_OVERFLOW_MISC = 4,
 384   /* Overflow warnings about reducing magnitude of constants in
 385      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 386   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 387 };
 388
 389 /* Whether to emit an overflow warning whose code is C.  */
 390 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 391
 392 #endif /* ! GCC_FLAGS_H */