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 /* 0 means straightforward implementation of complex divide acceptable.
 154    1 means wide ranges of inputs must work for complex divide.
 155    2 means C99-like requirements for complex multiply and divide.  */
 156
 157 extern int flag_complex_method;
 158
 159 /* Nonzero if we are only using compiler to check syntax errors.  */
 160
 161 extern int rtl_dump_and_exit;
 162
 163 /* Nonzero means we should save auxiliary info into a .X file.  */
 164
 165 extern int flag_gen_aux_info;
 166
 167 /* True if printing into -fdump-final-insns= dump.  */
 168
 169 extern bool final_insns_dump_p;
 170
 171 /* Nonzero means change certain warnings into errors.
 172    Usually these are warnings about failure to conform to some standard.  */
 173
 174 extern int flag_pedantic_errors;
 175
 176 /* Nonzero means make permerror produce warnings instead of errors.  */
 177
 178 extern int flag_permissive;
 179
 180 /* Nonzero if we are compiling code for a shared library, zero for
 181    executable.  */
 182
 183 extern int flag_shlib;
 184
 185 /* -dA causes debug information to be produced in
 186    the generated assembly code (to make it more readable).  This option
 187    is generally only of use to those who actually need to read the
 188    generated assembly code (perhaps while debugging the compiler itself).
 189    Currently, this switch is only used by dwarfout.c; however, it is intended
 190    to be a catchall for printing debug information in the assembler file.  */
 191
 192 extern int flag_debug_asm;
 193
 194 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 195
 196 extern int flag_next_runtime;
 197
 198 extern int flag_dump_rtl_in_asm;
 199
 200 /* The algorithm used for the integrated register allocator (IRA).  */
 201 enum ira_algorithm
 202 {
 203   IRA_ALGORITHM_CB,
 204   IRA_ALGORITHM_PRIORITY
 205 };
 206
 207 extern enum ira_algorithm flag_ira_algorithm;
 208
 209 /* The regions used for the integrated register allocator (IRA).  */
 210 enum ira_region
 211 {
 212   IRA_REGION_ONE,
 213   IRA_REGION_ALL,
 214   IRA_REGION_MIXED
 215 };
 216
 217 extern enum ira_region flag_ira_region;
 218
 219 /* The options for excess precision.  */
 220 enum excess_precision
 221 {
 222   EXCESS_PRECISION_DEFAULT,
 223   EXCESS_PRECISION_FAST,
 224   EXCESS_PRECISION_STANDARD
 225 };
 226
 227 /* The excess precision specified on the command line, or defaulted by
 228    the front end.  */
 229 extern enum excess_precision flag_excess_precision_cmdline;
 230 \f
 231 /* Other basic status info about current function.  */
 232
 233 /* Target-dependent global state.  */
 234 struct target_flag_state {
 235   /* Values of the -falign-* flags: how much to align labels in code.
 236      0 means `use default', 1 means `don't align'.
 237      For each variable, there is an _log variant which is the power
 238      of two not less than the variable, for .align output.  */
 239   int x_align_loops_log;
 240   int x_align_loops_max_skip;
 241   int x_align_jumps_log;
 242   int x_align_jumps_max_skip;
 243   int x_align_labels_log;
 244   int x_align_labels_max_skip;
 245   int x_align_functions_log;
 246
 247   /* The excess precision currently in effect.  */
 248   enum excess_precision x_flag_excess_precision;
 249 };
 250
 251 extern struct target_flag_state default_target_flag_state;
 252 #if SWITCHABLE_TARGET
 253 extern struct target_flag_state *this_target_flag_state;
 254 #else
 255 #define this_target_flag_state (&default_target_flag_state)
 256 #endif
 257
 258 #define align_loops_log \
 259   (this_target_flag_state->x_align_loops_log)
 260 #define align_loops_max_skip \
 261   (this_target_flag_state->x_align_loops_max_skip)
 262 #define align_jumps_log \
 263   (this_target_flag_state->x_align_jumps_log)
 264 #define align_jumps_max_skip \
 265   (this_target_flag_state->x_align_jumps_max_skip)
 266 #define align_labels_log \
 267   (this_target_flag_state->x_align_labels_log)
 268 #define align_labels_max_skip \
 269   (this_target_flag_state->x_align_labels_max_skip)
 270 #define align_functions_log \
 271   (this_target_flag_state->x_align_functions_log)
 272 #define flag_excess_precision \
 273   (this_target_flag_state->x_flag_excess_precision)
 274
 275 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 276 extern int flag_evaluation_order;
 277
 278 /* Value of the -G xx switch, and whether it was passed or not.  */
 279 extern unsigned HOST_WIDE_INT g_switch_value;
 280 extern bool g_switch_set;
 281
 282 /* Same for selective scheduling.  */
 283 extern bool sel_sched_switch_set;
 284
 285 /* Whether to run the warn_unused_result attribute pass.  */
 286 extern bool flag_warn_unused_result;
 287
 288 /* Nonzero if we dump in VCG format, not plain text.  */
 289 extern int dump_for_graph;
 290
 291 /* Selection of the graph form.  */
 292 enum graph_dump_types
 293 {
 294   no_graph = 0,
 295   vcg
 296 };
 297 extern enum graph_dump_types graph_dump_format;
 298
 299 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 300    warning message in case flag was set by -fprofile-{generate,use}.  */
 301 extern bool flag_speculative_prefetching_set;
 302
 303 /* Type of stack check.  */
 304 enum stack_check_type
 305 {
 306   /* Do not check the stack.  */
 307   NO_STACK_CHECK = 0,
 308
 309   /* Check the stack generically, i.e. assume no specific support
 310      from the target configuration files.  */
 311   GENERIC_STACK_CHECK,
 312
 313   /* Check the stack and rely on the target configuration files to
 314      check the static frame of functions, i.e. use the generic
 315      mechanism only for dynamic stack allocations.  */
 316   STATIC_BUILTIN_STACK_CHECK,
 317
 318   /* Check the stack and entirely rely on the target configuration
 319      files, i.e. do not use the generic mechanism at all.  */
 320   FULL_BUILTIN_STACK_CHECK
 321 };
 322 extern enum stack_check_type flag_stack_check;
 323
 324 /* Returns TRUE if generated code should match ABI version N or
 325    greater is in use.  */
 326
 327 #define abi_version_at_least(N) \
 328   (flag_abi_version == 0 || flag_abi_version >= (N))
 329
 330 /* Return whether the function should be excluded from
 331    instrumentation.  */
 332 extern bool flag_instrument_functions_exclude_p (tree fndecl);
 333
 334 /* True if overflow wraps around for the given integral type.  That
 335    is, TYPE_MAX + 1 == TYPE_MIN.  */
 336 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 337   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 338
 339 /* True if overflow is undefined for the given integral type.  We may
 340    optimize on the assumption that values in the type never overflow.
 341
 342    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 343    must issue a warning based on warn_strict_overflow.  In some cases
 344    it will be appropriate to issue the warning immediately, and in
 345    other cases it will be appropriate to simply set a flag and let the
 346    caller decide whether a warning is appropriate or not.  */
 347 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 348   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 349
 350 /* True if overflow for the given integral type should issue a
 351    trap.  */
 352 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 353   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 354
 355 /* True if pointer types have undefined overflow.  */
 356 #define POINTER_TYPE_OVERFLOW_UNDEFINED (flag_strict_overflow)
 357
 358 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 359    values here correspond to N.  */
 360
 361 enum warn_strict_overflow_code
 362 {
 363   /* Overflow warning that should be issued with -Wall: a questionable
 364      construct that is easy to avoid even when using macros.  Example:
 365      folding (x + CONSTANT > x) to 1.  */
 366   WARN_STRICT_OVERFLOW_ALL = 1,
 367   /* Overflow warning about folding a comparison to a constant because
 368      of undefined signed overflow, other than cases covered by
 369      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 370      (this is false when x == INT_MIN).  */
 371   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 372   /* Overflow warning about changes to comparisons other than folding
 373      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 374   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 375   /* Overflow warnings not covered by the above cases.  Example:
 376      folding ((x * 10) / 5) to (x * 2).  */
 377   WARN_STRICT_OVERFLOW_MISC = 4,
 378   /* Overflow warnings about reducing magnitude of constants in
 379      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 380   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 381 };
 382
 383 /* Whether to emit an overflow warning whose code is C.  */
 384 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 385
 386 #endif /* ! GCC_FLAGS_H */