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
   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 "options.h"
  26
  27 enum debug_info_type
  28 {
  29   NO_DEBUG,         /* Write no debug info.  */
  30   DBX_DEBUG,        /* Write BSD .stabs for DBX (using dbxout.c).  */
  31   SDB_DEBUG,        /* Write COFF for (old) SDB (using sdbout.c).  */
  32   DWARF2_DEBUG,     /* Write Dwarf v2 debug info (using dwarf2out.c).  */
  33   XCOFF_DEBUG,      /* Write IBM/Xcoff debug info (using dbxout.c).  */
  34   VMS_DEBUG,        /* Write VMS debug info (using vmsdbgout.c).  */
  35   VMS_AND_DWARF2_DEBUG /* Write VMS debug info (using vmsdbgout.c).
  36                           and DWARF v2 debug info (using dwarf2out.c).  */
  37 };
  38
  39 /* Specify which kind of debugging info to generate.  */
  40 extern enum debug_info_type write_symbols;
  41
  42 /* Names of debug_info_type, for error messages.  */
  43 extern const char *const debug_type_names[];
  44
  45 enum debug_info_level
  46 {
  47   DINFO_LEVEL_NONE,     /* Write no debugging info.  */
  48   DINFO_LEVEL_TERSE,    /* Write minimal info to support tracebacks only.  */
  49   DINFO_LEVEL_NORMAL,   /* Write info for all declarations (and line table).  */
  50   DINFO_LEVEL_VERBOSE   /* Write normal info plus #define/#undef info.  */
  51 };
  52
  53 /* Specify how much debugging info to generate.  */
  54 extern enum debug_info_level debug_info_level;
  55
  56 /* Nonzero means use GNU-only extensions in the generated symbolic
  57    debugging information.  */
  58 extern bool use_gnu_debug_info_extensions;
  59
  60 /* Enumerate visibility settings.  This is deliberately ordered from most
  61    to least visibility.  */
  62 #ifndef SYMBOL_VISIBILITY_DEFINED
  63 #define SYMBOL_VISIBILITY_DEFINED
  64 enum symbol_visibility
  65 {
  66   VISIBILITY_DEFAULT,
  67   VISIBILITY_PROTECTED,
  68   VISIBILITY_HIDDEN,
  69   VISIBILITY_INTERNAL
  70 };
  71 #endif
  72
  73 /* The default visibility for all symbols (unless overridden).  */
  74 extern enum symbol_visibility default_visibility;
  75
  76 struct visibility_flags
  77 {
  78   unsigned inpragma : 1;        /* True when in #pragma GCC visibility.  */
  79   unsigned inlines_hidden : 1;  /* True when -finlineshidden in effect.  */
  80 };
  81
  82 /* Global visibility options.  */
  83 extern struct visibility_flags visibility_options;
  84
  85 /* Nonzero means do optimizations.  -opt.  */
  86
  87 extern int optimize;
  88
  89 /* Nonzero means optimize for size.  -Os.  */
  90
  91 extern int optimize_size;
  92
  93 /* Do print extra warnings (such as for uninitialized variables).
  94    -W/-Wextra.  */
  95
  96 extern bool extra_warnings;
  97
  98 /* Nonzero to warn about unused variables, functions et.al.  Use
  99    set_Wunused() to update the -Wunused-* flags that correspond to the
 100    -Wunused option.  */
 101
 102 extern void set_Wunused (int setting);
 103
 104 /* Nonzero means warn about any objects definitions whose size is larger
 105    than N bytes.  Also want about function definitions whose returned
 106    values are larger than N bytes. The value N is in `larger_than_size'.  */
 107
 108 extern bool warn_larger_than;
 109 extern HOST_WIDE_INT larger_than_size;
 110
 111 /* Temporarily suppress certain warnings.
 112    This is set while reading code from a system header file.  */
 113
 114 extern int in_system_header;
 115
 116 /* Nonzero for -dp: annotate the assembly with a comment describing the
 117    pattern and alternative used.  */
 118
 119 extern int flag_print_asm_name;
 120 \f
 121 /* Now the symbols that are set with `-f' switches.  */
 122
 123 /* Nonzero means `char' should be signed.  */
 124
 125 extern int flag_signed_char;
 126
 127 /* Nonzero means give an enum type only as many bytes as it needs.  A value
 128    of 2 means it has not yet been initialized.  */
 129
 130 extern int flag_short_enums;
 131
 132 /* Nonzero for -fpcc-struct-return: return values the same way PCC does.  */
 133
 134 extern int flag_pcc_struct_return;
 135
 136 /* 0 means straightforward implementation of complex divide acceptable.
 137    1 means wide ranges of inputs must work for complex divide.
 138    2 means C99-like requirements for complex multiply and divide.  */
 139
 140 extern int flag_complex_method;
 141
 142 /* Nonzero means that we don't want inlining by virtue of -fno-inline,
 143    not just because the tree inliner turned us off.  */
 144
 145 extern int flag_really_no_inline;
 146
 147 /* Nonzero if we are only using compiler to check syntax errors.  */
 148
 149 extern int rtl_dump_and_exit;
 150
 151 /* Nonzero means we should save auxiliary info into a .X file.  */
 152
 153 extern int flag_gen_aux_info;
 154
 155 /* Nonzero means suppress output of instruction numbers and line number
 156    notes in debugging dumps.  */
 157
 158 extern int flag_dump_unnumbered;
 159
 160 /* Nonzero means change certain warnings into errors.
 161    Usually these are warnings about failure to conform to some standard.  */
 162
 163 extern int flag_pedantic_errors;
 164
 165 /* Nonzero if we are compiling code for a shared library, zero for
 166    executable.  */
 167
 168 extern int flag_shlib;
 169
 170 /* -dA causes debug information to be produced in
 171    the generated assembly code (to make it more readable).  This option
 172    is generally only of use to those who actually need to read the
 173    generated assembly code (perhaps while debugging the compiler itself).
 174    Currently, this switch is only used by dwarfout.c; however, it is intended
 175    to be a catchall for printing debug information in the assembler file.  */
 176
 177 extern int flag_debug_asm;
 178
 179 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 180
 181 extern int flag_next_runtime;
 182
 183 extern int flag_dump_rtl_in_asm;
 184
 185 /* If one, renumber instruction UIDs to reduce the number of
 186    unused UIDs if there are a lot of instructions.  If greater than
 187    one, unconditionally renumber instruction UIDs.  */
 188 extern int flag_renumber_insns;
 189 \f
 190 /* Other basic status info about current function.  */
 191
 192 /* Nonzero means current function must be given a frame pointer.
 193    Set in stmt.c if anything is allocated on the stack there.
 194    Set in reload1.c if anything is allocated on the stack there.  */
 195
 196 extern int frame_pointer_needed;
 197
 198 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 199 extern int flag_evaluation_order;
 200
 201 /* Value of the -G xx switch, and whether it was passed or not.  */
 202 extern unsigned HOST_WIDE_INT g_switch_value;
 203 extern bool g_switch_set;
 204
 205 /* Values of the -falign-* flags: how much to align labels in code.
 206    0 means `use default', 1 means `don't align'.
 207    For each variable, there is an _log variant which is the power
 208    of two not less than the variable, for .align output.  */
 209
 210 extern int align_loops_log;
 211 extern int align_loops_max_skip;
 212 extern int align_jumps_log;
 213 extern int align_jumps_max_skip;
 214 extern int align_labels_log;
 215 extern int align_labels_max_skip;
 216 extern int align_functions_log;
 217
 218 /* Like align_functions_log above, but used by front-ends to force the
 219    minimum function alignment.  Zero means no alignment is forced.  */
 220 extern int force_align_functions_log;
 221
 222 /* Nonzero if we dump in VCG format, not plain text.  */
 223 extern int dump_for_graph;
 224
 225 /* Selection of the graph form.  */
 226 enum graph_dump_types
 227 {
 228   no_graph = 0,
 229   vcg
 230 };
 231 extern enum graph_dump_types graph_dump_format;
 232
 233 /* Nonzero means to collect statistics which might be expensive
 234    and to print them when we are done.  */
 235 extern int flag_detailed_statistics;
 236
 237 /* Nonzero means that we defer emitting functions until they are actually
 238    used.  */
 239 extern int flag_remove_unreachable_functions;
 240
 241 /* Nonzero if we should track variables.  */
 242 extern int flag_var_tracking;
 243
 244 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 245    warning message in case flag was set by -fprofile-{generate,use}.  */
 246 extern bool flag_speculative_prefetching_set;
 247
 248 /* A string that's used when a random name is required.  NULL means
 249    to make it really random.  */
 250
 251 extern const char *flag_random_seed;
 252
 253 /* Returns TRUE if generated code should match ABI version N or
 254    greater is in use.  */
 255
 256 #define abi_version_at_least(N) \
 257   (flag_abi_version == 0 || flag_abi_version >= (N))
 258
 259 /* True if the given mode has a NaN representation and the treatment of
 260    NaN operands is important.  Certain optimizations, such as folding
 261    x * 0 into 0, are not correct for NaN operands, and are normally
 262    disabled for modes with NaNs.  The user can ask for them to be
 263    done anyway using the -funsafe-math-optimizations switch.  */
 264 #define HONOR_NANS(MODE) \
 265   (MODE_HAS_NANS (MODE) && !flag_finite_math_only)
 266
 267 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
 268 #define HONOR_SNANS(MODE) (flag_signaling_nans && HONOR_NANS (MODE))
 269
 270 /* As for HONOR_NANS, but true if the mode can represent infinity and
 271    the treatment of infinite values is important.  */
 272 #define HONOR_INFINITIES(MODE) \
 273   (MODE_HAS_INFINITIES (MODE) && !flag_finite_math_only)
 274
 275 /* Like HONOR_NANS, but true if the given mode distinguishes between
 276    positive and negative zero, and the sign of zero is important.  */
 277 #define HONOR_SIGNED_ZEROS(MODE) \
 278   (MODE_HAS_SIGNED_ZEROS (MODE) && !flag_unsafe_math_optimizations)
 279
 280 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
 281    and the rounding mode is important.  */
 282 #define HONOR_SIGN_DEPENDENT_ROUNDING(MODE) \
 283   (MODE_HAS_SIGN_DEPENDENT_ROUNDING (MODE) && flag_rounding_math)
 284
 285 /* True if overflow wraps around for the given integral type.  That
 286    is, TYPE_MAX + 1 == TYPE_MIN.  */
 287 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 288   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 289
 290 /* True if overflow is undefined for the given integral type.  We may
 291    optimize on the assumption that values in the type never overflow.
 292
 293    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 294    must issue a warning based on warn_strict_overflow.  In some cases
 295    it will be appropriate to issue the warning immediately, and in
 296    other cases it will be appropriate to simply set a flag and let the
 297    caller decide whether a warning is appropriate or not.  */
 298 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 299   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 300
 301 /* True if overflow for the given integral type should issue a
 302    trap.  */
 303 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 304   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 305
 306 /* True if pointer types have undefined overflow.  */
 307 #define POINTER_TYPE_OVERFLOW_UNDEFINED (flag_strict_overflow)
 308
 309 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 310    values here correspond to N.  */
 311
 312 enum warn_strict_overflow_code
 313 {
 314   /* Overflow warning that should be issued with -Wall: a questionable
 315      construct that is easy to avoid even when using macros.  Example:
 316      folding (x + CONSTANT > x) to 1.  */
 317   WARN_STRICT_OVERFLOW_ALL = 1,
 318   /* Overflow warning about folding a comparison to a constant because
 319      of undefined signed overflow, other than cases covered by
 320      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 321      (this is false when x == INT_MIN).  */
 322   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 323   /* Overflow warning about changes to comparisons other than folding
 324      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 325   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 326   /* Overflow warnings not covered by the above cases.  Example:
 327      folding ((x * 10) / 5) to (x * 2).  */
 328   WARN_STRICT_OVERFLOW_MISC = 4,
 329   /* Overflow warnings about reducing magnitude of constants in
 330      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 331   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 332 };
 333
 334 /* Whether to emit an overflow warning whose code is C.  */
 335 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 336
 337 #endif /* ! GCC_FLAGS_H */