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