flags.h revision 107604
1/* Compilation switch flag definitions for GCC.
2   Copyright (C) 1987, 1988, 1994, 1995, 1996, 1997, 1998, 1999, 2000
3   Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING.  If not, write to the Free
19Software Foundation, 59 Temple Place - Suite 330, Boston, MA
2002111-1307, USA.  */
21
22#ifndef GCC_FLAGS_H
23#define GCC_FLAGS_H
24
25/* Name of the input .c file being compiled.  */
26extern const char *main_input_filename;
27
28enum 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  DWARF_DEBUG,	    /* Write Dwarf debug info (using dwarfout.c).  */
34  DWARF2_DEBUG,	    /* Write Dwarf v2 debug info (using dwarf2out.c).  */
35  XCOFF_DEBUG,	    /* Write IBM/Xcoff debug info (using dbxout.c).  */
36  VMS_DEBUG,        /* Write VMS debug info (using vmsdbgout.c).  */
37  VMS_AND_DWARF2_DEBUG /* Write VMS debug info (using vmsdbgout.c).
38                          and DWARF v2 debug info (using dwarf2out.c).  */
39};
40
41/* Specify which kind of debugging info to generate.  */
42extern enum debug_info_type write_symbols;
43
44enum debug_info_level
45{
46  DINFO_LEVEL_NONE,	/* Write no debugging info.  */
47  DINFO_LEVEL_TERSE,	/* Write minimal info to support tracebacks only.  */
48  DINFO_LEVEL_NORMAL,	/* Write info for all declarations (and line table).  */
49  DINFO_LEVEL_VERBOSE	/* Write normal info plus #define/#undef info.  */
50};
51
52/* Specify how much debugging info to generate.  */
53extern enum debug_info_level debug_info_level;
54
55/* Nonzero means use GNU-only extensions in the generated symbolic
56   debugging information.  */
57extern int use_gnu_debug_info_extensions;
58
59/* Nonzero means do optimizations.  -opt.  */
60
61extern int optimize;
62
63/* Nonzero means optimize for size.  -Os.  */
64
65extern int optimize_size;
66
67/* Don't print functions as they are compiled and don't print
68   times taken by the various passes.  -quiet.  */
69
70extern int quiet_flag;
71
72/* Print times taken by the various passes.  -ftime-report.  */
73
74extern int time_report;
75
76/* Print memory still in use at end of compilation (which may have little
77   to do with peak memory consumption).  -fmem-report.  */
78
79extern int mem_report;
80
81/* Don't print warning messages.  -w.  */
82
83extern int inhibit_warnings;
84
85/* Don't suppress warnings from system headers.  -Wsystem-headers.  */
86
87extern int warn_system_headers;
88
89/* Do print extra warnings (such as for uninitialized variables).  -W.  */
90
91extern int extra_warnings;
92
93/* Nonzero to warn about unused variables, functions et.al.  Use
94   set_Wunused() to update the -Wunused-* flags that correspond to the
95   -Wunused option.  */
96
97extern void set_Wunused PARAMS ((int setting));
98
99extern int warn_unused_function;
100extern int warn_unused_label;
101extern int warn_unused_parameter;
102extern int warn_unused_variable;
103extern int warn_unused_value;
104
105/* Nonzero to warn about code which is never reached.  */
106
107extern int warn_notreached;
108
109/* Nonzero means warn if inline function is too large.  */
110
111extern int warn_inline;
112
113/* Nonzero to warn about variables used before they are initialized.  */
114
115extern int warn_uninitialized;
116
117/* Zero if unknown pragmas are ignored
118   One if the compiler should warn about an unknown pragma not in
119   a system include file.
120   Greater than one if the compiler should warn for all unknown
121   pragmas.  */
122
123extern int warn_unknown_pragmas;
124
125/* Nonzero means warn about all declarations which shadow others.  */
126
127extern int warn_shadow;
128
129/* Warn if a switch on an enum fails to have a case for every enum value.  */
130
131extern int warn_switch;
132
133/* Nonzero means warn about function definitions that default the return type
134   or that use a null return and have a return-type other than void.  */
135
136extern int warn_return_type;
137
138/* Warn about functions which might be candidates for attribute noreturn.  */
139
140extern int warn_missing_noreturn;
141
142/* Nonzero means warn about pointer casts that increase the required
143   alignment of the target type (and might therefore lead to a crash
144   due to a misaligned access).  */
145
146extern int warn_cast_align;
147
148/* Nonzero means warn about any objects definitions whose size is larger
149   than N bytes.  Also want about function definitions whose returned
150   values are larger than N bytes. The value N is in `larger_than_size'.  */
151
152extern int warn_larger_than;
153extern HOST_WIDE_INT larger_than_size;
154
155/* Warn if a function returns an aggregate,
156   since there are often incompatible calling conventions for doing this.  */
157
158extern int warn_aggregate_return;
159
160/* Warn if packed attribute on struct is unnecessary and inefficient.  */
161
162extern int warn_packed;
163
164/* Warn when gcc pads a structure to an alignment boundary.  */
165
166extern int warn_padded;
167
168/* Warn when an optimization pass is disabled.  */
169
170extern int warn_disabled_optimization;
171
172/* Nonzero means warn about uses of __attribute__((deprecated))
173   declarations.  */
174
175extern int warn_deprecated_decl;
176
177/* Nonzero if generating code to do profiling.  */
178
179extern int profile_flag;
180
181/* Nonzero if generating code to profile program flow graph arcs.  */
182
183extern int profile_arc_flag;
184
185/* Nonzero if generating info for gcov to calculate line test coverage.  */
186
187extern int flag_test_coverage;
188
189/* Nonzero indicates that branch taken probabilities should be calculated.  */
190
191extern int flag_branch_probabilities;
192
193/* Nonzero if basic blocks should be reordered.  */
194
195extern int flag_reorder_blocks;
196
197/* Nonzero if registers should be renamed.  */
198
199extern int flag_rename_registers;
200
201/* Nonzero for -pedantic switch: warn about anything
202   that standard C forbids.  */
203
204extern int pedantic;
205
206/* Temporarily suppress certain warnings.
207   This is set while reading code from a system header file.  */
208
209extern int in_system_header;
210
211/* Nonzero for -dp: annotate the assembly with a comment describing the
212   pattern and alternative used.  */
213
214extern int flag_print_asm_name;
215
216/* Now the symbols that are set with `-f' switches.  */
217
218/* Nonzero means `char' should be signed.  */
219
220extern int flag_signed_char;
221
222/* Nonzero means give an enum type only as many bytes as it needs.  */
223
224extern int flag_short_enums;
225
226/* Nonzero for -fcaller-saves: allocate values in regs that need to
227   be saved across function calls, if that produces overall better code.
228   Optional now, so people can test it.  */
229
230extern int flag_caller_saves;
231
232/* Nonzero for -fpcc-struct-return: return values the same way PCC does.  */
233
234extern int flag_pcc_struct_return;
235
236/* Nonzero for -fforce-mem: load memory value into a register
237   before arithmetic on it.  This makes better cse but slower compilation.  */
238
239extern int flag_force_mem;
240
241/* Nonzero for -fforce-addr: load memory address into a register before
242   reference to memory.  This makes better cse but slower compilation.  */
243
244extern int flag_force_addr;
245
246/* Nonzero for -fdefer-pop: don't pop args after each function call;
247   instead save them up to pop many calls' args with one insns.  */
248
249extern int flag_defer_pop;
250
251/* Nonzero for -ffloat-store: don't allocate floats and doubles
252   in extended-precision registers.  */
253
254extern int flag_float_store;
255
256/* Nonzero enables strength-reduction in loop.c.  */
257
258extern int flag_strength_reduce;
259
260/* Nonzero enables loop unrolling in unroll.c.  Only loops for which the
261   number of iterations can be calculated at compile-time (UNROLL_COMPLETELY,
262   UNROLL_MODULO) or at run-time (preconditioned to be UNROLL_MODULO) are
263   unrolled.  */
264
265extern int flag_unroll_loops;
266
267/* Nonzero enables loop unrolling in unroll.c.  All loops are unrolled.
268   This is generally not a win.  */
269
270extern int flag_unroll_all_loops;
271
272/* Nonzero forces all invariant computations in loops to be moved
273   outside the loop.  */
274
275extern int flag_move_all_movables;
276
277/* Nonzero enables prefetch optimizations for arrays in loops.  */
278
279extern int flag_prefetch_loop_arrays;
280
281/* Nonzero forces all general induction variables in loops to be
282   strength reduced.  */
283
284extern int flag_reduce_all_givs;
285
286/* Nonzero for -fcse-follow-jumps:
287   have cse follow jumps to do a more extensive job.  */
288
289extern int flag_cse_follow_jumps;
290
291/* Nonzero for -fcse-skip-blocks:
292   have cse follow a branch around a block.  */
293
294extern int flag_cse_skip_blocks;
295
296/* Nonzero for -fexpensive-optimizations:
297   perform miscellaneous relatively-expensive optimizations.  */
298extern int flag_expensive_optimizations;
299
300/* Nonzero for -fwritable-strings:
301   store string constants in data segment and don't uniquize them.  */
302
303extern int flag_writable_strings;
304
305/* Nonzero means don't put addresses of constant functions in registers.
306   Used for compiling the Unix kernel, where strange substitutions are
307   done on the assembly output.  */
308
309extern int flag_no_function_cse;
310
311/* Nonzero for -fomit-frame-pointer:
312   don't make a frame pointer in simple functions that don't require one.  */
313
314extern int flag_omit_frame_pointer;
315
316/* Nonzero to inhibit use of define_optimization peephole opts.  */
317
318extern int flag_no_peephole;
319
320/* Nonzero means all references through pointers are volatile.  */
321
322extern int flag_volatile;
323
324/* Nonzero means treat all global and extern variables as volatile.  */
325
326extern int flag_volatile_global;
327
328/* Nonzero means treat all static variables as volatile.  */
329
330extern int flag_volatile_static;
331
332/* Nonzero allows GCC to optimize sibling and tail recursive calls.  */
333
334extern int flag_optimize_sibling_calls;
335
336/* Nonzero means the front end generally wants `errno' maintained by math
337   operations, like built-in SQRT.  */
338
339extern int flag_errno_math;
340
341/* Nonzero means that unsafe floating-point math optimizations are allowed
342   for the sake of speed.  IEEE compliance is not guaranteed, and operations
343   are allowed to assume that their arguments and results are "normal"
344   (e.g., nonnegative for SQRT).  */
345
346extern int flag_unsafe_math_optimizations;
347
348/* Zero means that floating-point math operations cannot generate a
349   (user-visible) trap.  This is the case, for example, in nonstop
350   IEEE 754 arithmetic.  */
351
352extern int flag_trapping_math;
353
354/* 0 means straightforward implementation of complex divide acceptable.
355   1 means wide ranges of inputs must work for complex divide.
356   2 means C99-like requirements for complex divide (not yet implemented).  */
357
358extern int flag_complex_divide_method;
359
360/* Nonzero means to run loop optimizations twice.  */
361
362extern int flag_rerun_loop_opt;
363
364/* Nonzero means make functions that look like good inline candidates
365   go inline.  */
366
367extern int flag_inline_functions;
368
369/* Nonzero for -fkeep-inline-functions: even if we make a function
370   go inline everywhere, keep its definition around for debugging
371   purposes.  */
372
373extern int flag_keep_inline_functions;
374
375/* Nonzero means that functions declared `inline' will be treated
376   as `static'.  Prevents generation of zillions of copies of unused
377   static inline functions; instead, `inlines' are written out
378   only when actually used.  Used in conjunction with -g.  Also
379   does the right thing with #pragma interface.  */
380
381extern int flag_no_inline;
382
383/* Nonzero means that we don't want inlining by virtue of -fno-inline,
384   not just because the tree inliner turned us off.  */
385
386extern int flag_really_no_inline;
387
388/* Nonzero if we are only using compiler to check syntax errors.  */
389
390extern int flag_syntax_only;
391
392/* Nonzero means we should save auxiliary info into a .X file.  */
393
394extern int flag_gen_aux_info;
395
396/* Nonzero means make the text shared if supported.  */
397
398extern int flag_shared_data;
399
400/* flag_schedule_insns means schedule insns within basic blocks (before
401   local_alloc).
402   flag_schedule_insns_after_reload means schedule insns after
403   global_alloc.  */
404
405extern int flag_schedule_insns;
406extern int flag_schedule_insns_after_reload;
407
408/* The following flags have effect only for scheduling before register
409   allocation:
410
411   flag_schedule_interblock means schedule insns accross basic blocks.
412   flag_schedule_speculative means allow speculative motion of non-load insns.
413   flag_schedule_speculative_load means allow speculative motion of some
414   load insns.
415   flag_schedule_speculative_load_dangerous allows speculative motion of more
416   load insns.  */
417
418extern int flag_schedule_interblock;
419extern int flag_schedule_speculative;
420extern int flag_schedule_speculative_load;
421extern int flag_schedule_speculative_load_dangerous;
422
423/* flag_branch_on_count_reg means try to replace add-1,compare,branch tupple
424   by a cheaper branch, on a count register.  */
425extern int flag_branch_on_count_reg;
426
427/* This option is set to 1 on -fsingle-precision-constant option which is
428   used to convert the floating point constants to single precision
429   constants.  */
430
431extern int flag_single_precision_constant;
432
433/* Nonzero means put things in delayed-branch slots if supported.  */
434
435extern int flag_delayed_branch;
436
437/* Nonzero means suppress output of instruction numbers and line number
438   notes in debugging dumps.  */
439
440extern int flag_dump_unnumbered;
441
442/* Nonzero means pretend it is OK to examine bits of target floats,
443   even if that isn't true.  The resulting code will have incorrect constants,
444   but the same series of instructions that the native compiler would make.  */
445
446extern int flag_pretend_float;
447
448/* Nonzero means change certain warnings into errors.
449   Usually these are warnings about failure to conform to some standard.  */
450
451extern int flag_pedantic_errors;
452
453/* Nonzero means generate position-independent code.
454   This is not fully implemented yet.  */
455
456extern int flag_pic;
457
458/* Nonzero means generate extra code for exception handling and enable
459   exception handling.  */
460
461extern int flag_exceptions;
462
463/* Nonzero means generate frame unwind info table when supported */
464
465extern int flag_unwind_tables;
466
467/* Nonzero means generate frame unwind info table exact at each insn boundary */
468
469extern int flag_asynchronous_unwind_tables;
470
471/* Nonzero means don't place uninitialized global data in common storage
472   by default.  */
473
474extern int flag_no_common;
475
476/* -finhibit-size-directive inhibits output of .size for ELF.
477   This is used only for compiling crtstuff.c,
478   and it may be extended to other effects
479   needed for crtstuff.c on other systems.  */
480extern int flag_inhibit_size_directive;
481
482/* Nonzero means place each function into its own section on those platforms
483   which support arbitrary section names and unlimited numbers of sections.  */
484
485extern int flag_function_sections;
486
487/* ... and similar for data.  */
488
489extern int flag_data_sections;
490
491/* -fverbose-asm causes extra commentary information to be produced in
492   the generated assembly code (to make it more readable).  This option
493   is generally only of use to those who actually need to read the
494   generated assembly code (perhaps while debugging the compiler itself).
495   -fno-verbose-asm, the default, causes the extra information
496   to not be added and is useful when comparing two assembler files.  */
497
498extern int flag_verbose_asm;
499
500/* -dA causes debug information to be produced in
501   the generated assembly code (to make it more readable).  This option
502   is generally only of use to those who actually need to read the
503   generated assembly code (perhaps while debugging the compiler itself).
504   Currently, this switch is only used by dwarfout.c; however, it is intended
505   to be a catchall for printing debug information in the assembler file.  */
506
507extern int flag_debug_asm;
508
509extern int flag_dump_rtl_in_asm;
510
511/* -fgnu-linker specifies use of the GNU linker for initializations.
512   -fno-gnu-linker says that collect will be used.  */
513extern int flag_gnu_linker;
514
515/* Tag all structures with __attribute__(packed) */
516extern int flag_pack_struct;
517
518/* This flag is only tested if alias checking is enabled.
519   0 if pointer arguments may alias each other.  True in C.
520   1 if pointer arguments may not alias each other but may alias
521   global variables.
522   2 if pointer arguments may not alias each other and may not
523   alias global variables.  True in Fortran.
524   The value is ignored if flag_alias_check is 0.  */
525extern int flag_argument_noalias;
526
527/* Nonzero if we should do (language-dependent) alias analysis.
528   Typically, this analysis will assume that expressions of certain
529   types do not alias expressions of certain other types.  Only used
530   if alias analysis (in general) is enabled.  */
531extern int flag_strict_aliasing;
532
533/* Emit code to probe the stack, to help detect stack overflow; also
534   may cause large objects to be allocated dynamically.  */
535extern int flag_stack_check;
536
537/* Do the full regmove optimization pass.  */
538extern int flag_regmove;
539
540/* Instrument functions with calls at entry and exit, for profiling.  */
541extern int flag_instrument_function_entry_exit;
542
543/* Perform a peephole pass before sched2.  */
544extern int flag_peephole2;
545
546/* Try to guess branch probablities.  */
547extern int flag_guess_branch_prob;
548
549/* -fbounded-pointers causes gcc to compile pointers as composite
550   objects occupying three words: the pointer value, the base address
551   of the referent object, and the address immediately beyond the end
552   of the referent object.  The base and extent allow us to perform
553   runtime bounds checking.  -fbounded-pointers implies -fcheck-bounds.  */
554extern int flag_bounded_pointers;
555
556/* -fcheck-bounds causes gcc to generate array bounds checks.
557   For C, C++: defaults to value of flag_bounded_pointers.
558   For ObjC: defaults to off.
559   For Java: defaults to on.
560   For Fortran: defaults to off.
561   For CHILL: defaults to off.  */
562extern int flag_bounds_check;
563
564/* This will attempt to merge constant section constants, if 1 only
565   string constants and constants from constant pool, if 2 also constant
566   variables.  */
567extern int flag_merge_constants;
568
569/* If one, renumber instruction UIDs to reduce the number of
570   unused UIDs if there are a lot of instructions.  If greater than
571   one, unconditionally renumber instruction UIDs.  */
572extern int flag_renumber_insns;
573
574/* Other basic status info about current function.  */
575
576/* Nonzero means current function must be given a frame pointer.
577   Set in stmt.c if anything is allocated on the stack there.
578   Set in reload1.c if anything is allocated on the stack there.  */
579
580extern int frame_pointer_needed;
581
582/* Nonzero if the generated code should trap on signed overflow
583   for PLUS / SUB / MULT.  */
584extern int flag_trapv;
585
586/* Value of the -G xx switch, and whether it was passed or not.  */
587extern int g_switch_value;
588extern int g_switch_set;
589
590/* Values of the -falign-* flags: how much to align labels in code.
591   0 means `use default', 1 means `don't align'.
592   For each variable, there is an _log variant which is the power
593   of two not less than the variable, for .align output.  */
594
595extern int align_loops;
596extern int align_loops_log;
597extern int align_loops_max_skip;
598extern int align_jumps;
599extern int align_jumps_log;
600extern int align_jumps_max_skip;
601extern int align_labels;
602extern int align_labels_log;
603extern int align_labels_max_skip;
604extern int align_functions;
605extern int align_functions_log;
606
607/* Like align_functions_log above, but used by front-ends to force the
608   minimum function alignment.  Zero means no alignment is forced.  */
609extern int force_align_functions_log;
610
611/* Nonzero if we dump in VCG format, not plain text.  */
612extern int dump_for_graph;
613
614/* Selection of the graph form.  */
615enum graph_dump_types
616{
617  no_graph = 0,
618  vcg
619};
620extern enum graph_dump_types graph_dump_format;
621
622/* Nonzero means ignore `#ident' directives.  0 means handle them.
623   On SVR4 targets, it also controls whether or not to emit a
624   string identifying the compiler.  */
625
626extern int flag_no_ident;
627
628/* Nonzero if we want to perform enhanced load motion during gcse.  */
629
630extern int flag_gcse_lm;
631
632/* Nonzero if we want to perform store motion after gcse.  */
633
634extern int flag_gcse_sm;
635
636
637/* Nonzero means we should do dwarf2 duplicate elimination.  */
638
639extern int flag_eliminate_dwarf2_dups;
640
641/* Non-zero means to collect statistics which might be expensive
642   and to print them when we are done.  */
643extern int flag_detailed_statistics;
644
645/* Nonzero means enable synchronous exceptions for non-call instructions.  */
646extern int flag_non_call_exceptions;
647
648#endif /* ! GCC_FLAGS_H */
649