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 /* Nonzero means change certain warnings into errors.
 186    Usually these are warnings about failure to conform to some standard.  */
 187
 188 extern int flag_pedantic_errors;
 189
 190 /* Nonzero means make permerror produce warnings instead of errors.  */
 191
 192 extern int flag_permissive;
 193
 194 /* Nonzero if we are compiling code for a shared library, zero for
 195    executable.  */
 196
 197 extern int flag_shlib;
 198
 199 /* -dA causes debug information to be produced in
 200    the generated assembly code (to make it more readable).  This option
 201    is generally only of use to those who actually need to read the
 202    generated assembly code (perhaps while debugging the compiler itself).
 203    Currently, this switch is only used by dwarfout.c; however, it is intended
 204    to be a catchall for printing debug information in the assembler file.  */
 205
 206 extern int flag_debug_asm;
 207
 208 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 209
 210 extern int flag_next_runtime;
 211
 212 extern int flag_dump_rtl_in_asm;
 213
 214 /* The algorithm used for the integrated register allocator (IRA).  */
 215 enum ira_algorithm
 216 {
 217   IRA_ALGORITHM_CB,
 218   IRA_ALGORITHM_PRIORITY
 219 };
 220
 221 extern enum ira_algorithm flag_ira_algorithm;
 222
 223 /* The regions used for the integrated register allocator (IRA).  */
 224 enum ira_region
 225 {
 226   IRA_REGION_ONE,
 227   IRA_REGION_ALL,
 228   IRA_REGION_MIXED
 229 };
 230
 231 extern enum ira_region flag_ira_region;
 232
 233 extern unsigned int flag_ira_verbose;
 234
 235 /* The options for excess precision.  */
 236 enum excess_precision
 237 {
 238   EXCESS_PRECISION_DEFAULT,
 239   EXCESS_PRECISION_FAST,
 240   EXCESS_PRECISION_STANDARD
 241 };
 242
 243 /* The excess precision specified on the command line, or defaulted by
 244    the front end.  */
 245 extern enum excess_precision flag_excess_precision_cmdline;
 246
 247 /* The excess precision currently in effect.  */
 248 extern enum excess_precision flag_excess_precision;
 249
 250 \f
 251 /* Other basic status info about current function.  */
 252
 253 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 254 extern int flag_evaluation_order;
 255
 256 /* Value of the -G xx switch, and whether it was passed or not.  */
 257 extern unsigned HOST_WIDE_INT g_switch_value;
 258 extern bool g_switch_set;
 259
 260 /* Same for selective scheduling.  */
 261 extern bool sel_sched_switch_set;
 262
 263 /* Whether to run the warn_unused_result attribute pass.  */
 264 extern bool flag_warn_unused_result;
 265
 266 /* Values of the -falign-* flags: how much to align labels in code.
 267    0 means `use default', 1 means `don't align'.
 268    For each variable, there is an _log variant which is the power
 269    of two not less than the variable, for .align output.  */
 270
 271 extern int align_loops_log;
 272 extern int align_loops_max_skip;
 273 extern int align_jumps_log;
 274 extern int align_jumps_max_skip;
 275 extern int align_labels_log;
 276 extern int align_labels_max_skip;
 277 extern int align_functions_log;
 278
 279 /* Nonzero if we dump in VCG format, not plain text.  */
 280 extern int dump_for_graph;
 281
 282 /* Selection of the graph form.  */
 283 enum graph_dump_types
 284 {
 285   no_graph = 0,
 286   vcg
 287 };
 288 extern enum graph_dump_types graph_dump_format;
 289
 290 /* Nonzero means to collect statistics which might be expensive
 291    and to print them when we are done.  */
 292 extern int flag_detailed_statistics;
 293
 294 /* Nonzero means that we defer emitting functions until they are actually
 295    used.  */
 296 extern int flag_remove_unreachable_functions;
 297
 298 /* Nonzero if we should track variables.  */
 299 extern int flag_var_tracking;
 300
 301 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 302    warning message in case flag was set by -fprofile-{generate,use}.  */
 303 extern bool flag_speculative_prefetching_set;
 304
 305 /* Type of stack check.  */
 306 enum stack_check_type
 307 {
 308   /* Do not check the stack.  */
 309   NO_STACK_CHECK = 0,
 310
 311   /* Check the stack generically, i.e. assume no specific support
 312      from the target configuration files.  */
 313   GENERIC_STACK_CHECK,
 314
 315   /* Check the stack and rely on the target configuration files to
 316      check the static frame of functions, i.e. use the generic
 317      mechanism only for dynamic stack allocations.  */
 318   STATIC_BUILTIN_STACK_CHECK,
 319
 320   /* Check the stack and entirely rely on the target configuration
 321      files, i.e. do not use the generic mechanism at all.  */
 322   FULL_BUILTIN_STACK_CHECK
 323 };
 324 extern enum stack_check_type flag_stack_check;
 325
 326 /* Returns TRUE if generated code should match ABI version N or
 327    greater is in use.  */
 328
 329 #define abi_version_at_least(N) \
 330   (flag_abi_version == 0 || flag_abi_version >= (N))
 331
 332 /* Return whether the function should be excluded from
 333    instrumentation.  */
 334 extern bool flag_instrument_functions_exclude_p (tree fndecl);
 335
 336 /* True if overflow wraps around for the given integral type.  That
 337    is, TYPE_MAX + 1 == TYPE_MIN.  */
 338 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 339   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 340
 341 /* True if overflow is undefined for the given integral type.  We may
 342    optimize on the assumption that values in the type never overflow.
 343
 344    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 345    must issue a warning based on warn_strict_overflow.  In some cases
 346    it will be appropriate to issue the warning immediately, and in
 347    other cases it will be appropriate to simply set a flag and let the
 348    caller decide whether a warning is appropriate or not.  */
 349 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 350   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 351
 352 /* True if overflow for the given integral type should issue a
 353    trap.  */
 354 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 355   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 356
 357 /* True if pointer types have undefined overflow.  */
 358 #define POINTER_TYPE_OVERFLOW_UNDEFINED (flag_strict_overflow)
 359
 360 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 361    values here correspond to N.  */
 362
 363 enum warn_strict_overflow_code
 364 {
 365   /* Overflow warning that should be issued with -Wall: a questionable
 366      construct that is easy to avoid even when using macros.  Example:
 367      folding (x + CONSTANT > x) to 1.  */
 368   WARN_STRICT_OVERFLOW_ALL = 1,
 369   /* Overflow warning about folding a comparison to a constant because
 370      of undefined signed overflow, other than cases covered by
 371      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 372      (this is false when x == INT_MIN).  */
 373   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 374   /* Overflow warning about changes to comparisons other than folding
 375      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 376   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 377   /* Overflow warnings not covered by the above cases.  Example:
 378      folding ((x * 10) / 5) to (x * 2).  */
 379   WARN_STRICT_OVERFLOW_MISC = 4,
 380   /* Overflow warnings about reducing magnitude of constants in
 381      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 382   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 383 };
 384
 385 /* Whether to emit an overflow warning whose code is C.  */
 386 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 387
 388 #endif /* ! GCC_FLAGS_H */