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 /* Run the second compilation of -fcompare-debug.  Not defined using
  81    Var in common.opt because this is used in Ada code and so must be
  82    an actual variable not a macro.  */
  83 extern int flag_compare_debug;
  84
  85 /* Enumerate visibility settings.  This is deliberately ordered from most
  86    to least visibility.  */
  87 #ifndef SYMBOL_VISIBILITY_DEFINED
  88 #define SYMBOL_VISIBILITY_DEFINED
  89 enum symbol_visibility
  90 {
  91   VISIBILITY_DEFAULT,
  92   VISIBILITY_PROTECTED,
  93   VISIBILITY_HIDDEN,
  94   VISIBILITY_INTERNAL
  95 };
  96 #endif
  97
  98 /* The default visibility for all symbols (unless overridden).  */
  99 extern enum symbol_visibility default_visibility;
 100
 101 struct visibility_flags
 102 {
 103   unsigned inpragma : 1;        /* True when in #pragma GCC visibility.  */
 104   unsigned inlines_hidden : 1;  /* True when -finlineshidden in effect.  */
 105 };
 106
 107 /* Global visibility options.  */
 108 extern struct visibility_flags visibility_options;
 109
 110 /* Nonzero means do optimizations.  -opt.  */
 111
 112 extern int optimize;
 113
 114 /* Nonzero means optimize for size.  -Os.  */
 115
 116 extern int optimize_size;
 117
 118 /* True if this is the LTO front end (lto1).  This is used to disable
 119    gimple generation and lowering passes that are normally run on the
 120    output of a front end.  These passes must be bypassed for lto since
 121    they have already been done before the gimple was written.  */
 122
 123 extern bool in_lto_p;
 124
 125 /* Nonzero if we should write GIMPLE bytecode for link-time optimization.  */
 126
 127 extern int flag_generate_lto;
 128
 129 /* Used to set the level of -Wstrict-aliasing, when no level is specified.
 130    The external way to set the default level is to use
 131    -Wstrict-aliasing=level.
 132    ONOFF is assumed to take value 1 when -Wstrict-aliasing is specified,
 133    and 0 otherwise.  After calling this function, wstrict_aliasing will be
 134    set to the default value of -Wstrict_aliasing=level.  */
 135
 136 extern void set_Wstrict_aliasing (int onoff);
 137
 138 /* Nonzero means warn about any objects definitions whose size is larger
 139    than N bytes.  Also want about function definitions whose returned
 140    values are larger than N bytes. The value N is in `larger_than_size'.  */
 141
 142 extern bool warn_larger_than;
 143 extern HOST_WIDE_INT larger_than_size;
 144
 145 /* Nonzero means warn about any function whose frame size is larger
 146    than N bytes. */
 147
 148 extern bool warn_frame_larger_than;
 149 extern HOST_WIDE_INT frame_larger_than_size;
 150
 151 /* Nonzero for -dp: annotate the assembly with a comment describing the
 152    pattern and alternative used.  */
 153
 154 extern int flag_print_asm_name;
 155 \f
 156 /* Now the symbols that are set with `-f' switches.  */
 157
 158 /* 0 means straightforward implementation of complex divide acceptable.
 159    1 means wide ranges of inputs must work for complex divide.
 160    2 means C99-like requirements for complex multiply and divide.  */
 161
 162 extern int flag_complex_method;
 163
 164 /* Nonzero if we are only using compiler to check syntax errors.  */
 165
 166 extern int rtl_dump_and_exit;
 167
 168 /* Nonzero means we should save auxiliary info into a .X file.  */
 169
 170 extern int flag_gen_aux_info;
 171
 172 /* True if printing into -fdump-final-insns= dump.  */
 173
 174 extern bool final_insns_dump_p;
 175
 176 /* Nonzero means change certain warnings into errors.
 177    Usually these are warnings about failure to conform to some standard.  */
 178
 179 extern int flag_pedantic_errors;
 180
 181 /* Nonzero means make permerror produce warnings instead of errors.  */
 182
 183 extern int flag_permissive;
 184
 185 /* Nonzero if we are compiling code for a shared library, zero for
 186    executable.  */
 187
 188 extern int flag_shlib;
 189
 190 /* -dA causes debug information to be produced in
 191    the generated assembly code (to make it more readable).  This option
 192    is generally only of use to those who actually need to read the
 193    generated assembly code (perhaps while debugging the compiler itself).
 194    Currently, this switch is only used by dwarfout.c; however, it is intended
 195    to be a catchall for printing debug information in the assembler file.  */
 196
 197 extern int flag_debug_asm;
 198
 199 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 200
 201 extern int flag_next_runtime;
 202
 203 extern int flag_dump_rtl_in_asm;
 204
 205 /* The algorithm used for the integrated register allocator (IRA).  */
 206 enum ira_algorithm
 207 {
 208   IRA_ALGORITHM_CB,
 209   IRA_ALGORITHM_PRIORITY
 210 };
 211
 212 extern enum ira_algorithm flag_ira_algorithm;
 213
 214 /* The regions used for the integrated register allocator (IRA).  */
 215 enum ira_region
 216 {
 217   IRA_REGION_ONE,
 218   IRA_REGION_ALL,
 219   IRA_REGION_MIXED
 220 };
 221
 222 extern enum ira_region flag_ira_region;
 223
 224 /* The options for excess precision.  */
 225 enum excess_precision
 226 {
 227   EXCESS_PRECISION_DEFAULT,
 228   EXCESS_PRECISION_FAST,
 229   EXCESS_PRECISION_STANDARD
 230 };
 231
 232 /* The excess precision specified on the command line, or defaulted by
 233    the front end.  */
 234 extern enum excess_precision flag_excess_precision_cmdline;
 235 \f
 236 /* Other basic status info about current function.  */
 237
 238 /* Target-dependent global state.  */
 239 struct target_flag_state {
 240   /* Values of the -falign-* flags: how much to align labels in code.
 241      0 means `use default', 1 means `don't align'.
 242      For each variable, there is an _log variant which is the power
 243      of two not less than the variable, for .align output.  */
 244   int x_align_loops_log;
 245   int x_align_loops_max_skip;
 246   int x_align_jumps_log;
 247   int x_align_jumps_max_skip;
 248   int x_align_labels_log;
 249   int x_align_labels_max_skip;
 250   int x_align_functions_log;
 251
 252   /* The excess precision currently in effect.  */
 253   enum excess_precision x_flag_excess_precision;
 254 };
 255
 256 extern struct target_flag_state default_target_flag_state;
 257 #if SWITCHABLE_TARGET
 258 extern struct target_flag_state *this_target_flag_state;
 259 #else
 260 #define this_target_flag_state (&default_target_flag_state)
 261 #endif
 262
 263 #define align_loops_log \
 264   (this_target_flag_state->x_align_loops_log)
 265 #define align_loops_max_skip \
 266   (this_target_flag_state->x_align_loops_max_skip)
 267 #define align_jumps_log \
 268   (this_target_flag_state->x_align_jumps_log)
 269 #define align_jumps_max_skip \
 270   (this_target_flag_state->x_align_jumps_max_skip)
 271 #define align_labels_log \
 272   (this_target_flag_state->x_align_labels_log)
 273 #define align_labels_max_skip \
 274   (this_target_flag_state->x_align_labels_max_skip)
 275 #define align_functions_log \
 276   (this_target_flag_state->x_align_functions_log)
 277 #define flag_excess_precision \
 278   (this_target_flag_state->x_flag_excess_precision)
 279
 280 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 281 extern int flag_evaluation_order;
 282
 283 /* Value of the -G xx switch, and whether it was passed or not.  */
 284 extern unsigned HOST_WIDE_INT g_switch_value;
 285 extern bool g_switch_set;
 286
 287 /* Same for selective scheduling.  */
 288 extern bool sel_sched_switch_set;
 289
 290 /* Whether to run the warn_unused_result attribute pass.  */
 291 extern bool flag_warn_unused_result;
 292
 293 /* Nonzero if we dump in VCG format, not plain text.  */
 294 extern int dump_for_graph;
 295
 296 /* Selection of the graph form.  */
 297 enum graph_dump_types
 298 {
 299   no_graph = 0,
 300   vcg
 301 };
 302 extern enum graph_dump_types graph_dump_format;
 303
 304 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 305    warning message in case flag was set by -fprofile-{generate,use}.  */
 306 extern bool flag_speculative_prefetching_set;
 307
 308 /* Type of stack check.  */
 309 enum stack_check_type
 310 {
 311   /* Do not check the stack.  */
 312   NO_STACK_CHECK = 0,
 313
 314   /* Check the stack generically, i.e. assume no specific support
 315      from the target configuration files.  */
 316   GENERIC_STACK_CHECK,
 317
 318   /* Check the stack and rely on the target configuration files to
 319      check the static frame of functions, i.e. use the generic
 320      mechanism only for dynamic stack allocations.  */
 321   STATIC_BUILTIN_STACK_CHECK,
 322
 323   /* Check the stack and entirely rely on the target configuration
 324      files, i.e. do not use the generic mechanism at all.  */
 325   FULL_BUILTIN_STACK_CHECK
 326 };
 327 extern enum stack_check_type flag_stack_check;
 328
 329 /* Returns TRUE if generated code should match ABI version N or
 330    greater is in use.  */
 331
 332 #define abi_version_at_least(N) \
 333   (flag_abi_version == 0 || flag_abi_version >= (N))
 334
 335 /* Return whether the function should be excluded from
 336    instrumentation.  */
 337 extern bool flag_instrument_functions_exclude_p (tree fndecl);
 338
 339 /* True if overflow wraps around for the given integral type.  That
 340    is, TYPE_MAX + 1 == TYPE_MIN.  */
 341 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 342   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 343
 344 /* True if overflow is undefined for the given integral type.  We may
 345    optimize on the assumption that values in the type never overflow.
 346
 347    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 348    must issue a warning based on warn_strict_overflow.  In some cases
 349    it will be appropriate to issue the warning immediately, and in
 350    other cases it will be appropriate to simply set a flag and let the
 351    caller decide whether a warning is appropriate or not.  */
 352 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 353   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 354
 355 /* True if overflow for the given integral type should issue a
 356    trap.  */
 357 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 358   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 359
 360 /* True if pointer types have undefined overflow.  */
 361 #define POINTER_TYPE_OVERFLOW_UNDEFINED (flag_strict_overflow)
 362
 363 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 364    values here correspond to N.  */
 365
 366 enum warn_strict_overflow_code
 367 {
 368   /* Overflow warning that should be issued with -Wall: a questionable
 369      construct that is easy to avoid even when using macros.  Example:
 370      folding (x + CONSTANT > x) to 1.  */
 371   WARN_STRICT_OVERFLOW_ALL = 1,
 372   /* Overflow warning about folding a comparison to a constant because
 373      of undefined signed overflow, other than cases covered by
 374      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 375      (this is false when x == INT_MIN).  */
 376   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 377   /* Overflow warning about changes to comparisons other than folding
 378      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 379   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 380   /* Overflow warnings not covered by the above cases.  Example:
 381      folding ((x * 10) / 5) to (x * 2).  */
 382   WARN_STRICT_OVERFLOW_MISC = 4,
 383   /* Overflow warnings about reducing magnitude of constants in
 384      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 385   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 386 };
 387
 388 /* Whether to emit an overflow warning whose code is C.  */
 389 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 390
 391 #endif /* ! GCC_FLAGS_H */