1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2009, Free Software Foundation, Inc. *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 3, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License distributed with GNAT; see file COPYING3. If not see *
19 * <http://www.gnu.org/licenses/>. *
21 * GNAT was originally developed by the GNAT team at New York University. *
22 * Extensive contributions were provided by Ada Core Technologies Inc. *
24 ****************************************************************************/
26 /* This file contains parts of the compiler that are required for interfacing
27 with GCC but otherwise do nothing and parts of Gigi that need to know
32 #include "coretypes.h"
35 #include "diagnostic.h"
46 #include "langhooks.h"
47 #include "langhooks-def.h"
50 #include "tree-inline.h"
53 #include "adadecode.h"
67 static bool gnat_init (void);
68 static unsigned int gnat_init_options (unsigned int, const char **);
69 static int gnat_handle_option (size_t, const char *, int);
70 static bool gnat_post_options (const char **);
71 static alias_set_type gnat_get_alias_set (tree);
72 static void gnat_print_decl (FILE *, tree, int);
73 static void gnat_print_type (FILE *, tree, int);
74 static const char *gnat_printable_name (tree, int);
75 static const char *gnat_dwarf_name (tree, int);
76 static tree gnat_return_tree (tree);
77 static int gnat_eh_type_covers (tree, tree);
78 static void gnat_parse_file (int);
79 static void internal_error_function (const char *, va_list *);
80 static tree gnat_type_max_size (const_tree);
82 /* Definitions for our language-specific hooks. */
84 #undef LANG_HOOKS_NAME
85 #define LANG_HOOKS_NAME "GNU Ada"
86 #undef LANG_HOOKS_IDENTIFIER_SIZE
87 #define LANG_HOOKS_IDENTIFIER_SIZE sizeof (struct tree_identifier)
88 #undef LANG_HOOKS_INIT
89 #define LANG_HOOKS_INIT gnat_init
90 #undef LANG_HOOKS_INIT_OPTIONS
91 #define LANG_HOOKS_INIT_OPTIONS gnat_init_options
92 #undef LANG_HOOKS_HANDLE_OPTION
93 #define LANG_HOOKS_HANDLE_OPTION gnat_handle_option
94 #undef LANG_HOOKS_POST_OPTIONS
95 #define LANG_HOOKS_POST_OPTIONS gnat_post_options
96 #undef LANG_HOOKS_PARSE_FILE
97 #define LANG_HOOKS_PARSE_FILE gnat_parse_file
98 #undef LANG_HOOKS_HASH_TYPES
99 #define LANG_HOOKS_HASH_TYPES false
100 #undef LANG_HOOKS_GETDECLS
101 #define LANG_HOOKS_GETDECLS lhd_return_null_tree_v
102 #undef LANG_HOOKS_PUSHDECL
103 #define LANG_HOOKS_PUSHDECL gnat_return_tree
104 #undef LANG_HOOKS_WRITE_GLOBALS
105 #define LANG_HOOKS_WRITE_GLOBALS gnat_write_global_declarations
106 #undef LANG_HOOKS_GET_ALIAS_SET
107 #define LANG_HOOKS_GET_ALIAS_SET gnat_get_alias_set
108 #undef LANG_HOOKS_MARK_ADDRESSABLE
109 #define LANG_HOOKS_MARK_ADDRESSABLE gnat_mark_addressable
110 #undef LANG_HOOKS_PRINT_DECL
111 #define LANG_HOOKS_PRINT_DECL gnat_print_decl
112 #undef LANG_HOOKS_PRINT_TYPE
113 #define LANG_HOOKS_PRINT_TYPE gnat_print_type
114 #undef LANG_HOOKS_TYPE_MAX_SIZE
115 #define LANG_HOOKS_TYPE_MAX_SIZE gnat_type_max_size
116 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
117 #define LANG_HOOKS_DECL_PRINTABLE_NAME gnat_printable_name
118 #undef LANG_HOOKS_DWARF_NAME
119 #define LANG_HOOKS_DWARF_NAME gnat_dwarf_name
120 #undef LANG_HOOKS_GIMPLIFY_EXPR
121 #define LANG_HOOKS_GIMPLIFY_EXPR gnat_gimplify_expr
122 #undef LANG_HOOKS_TYPE_FOR_MODE
123 #define LANG_HOOKS_TYPE_FOR_MODE gnat_type_for_mode
124 #undef LANG_HOOKS_TYPE_FOR_SIZE
125 #define LANG_HOOKS_TYPE_FOR_SIZE gnat_type_for_size
126 #undef LANG_HOOKS_TYPES_COMPATIBLE_P
127 #define LANG_HOOKS_TYPES_COMPATIBLE_P gnat_types_compatible_p
128 #undef LANG_HOOKS_ATTRIBUTE_TABLE
129 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
130 #undef LANG_HOOKS_BUILTIN_FUNCTION
131 #define LANG_HOOKS_BUILTIN_FUNCTION gnat_builtin_function
133 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
135 /* How much we want of our DWARF extensions. Some of our dwarf+ extensions
136 are incompatible with regular GDB versions, so we must make sure to only
137 produce them on explicit request. This is eventually reflected into the
138 use_gnu_debug_info_extensions common flag for later processing. */
139 static int gnat_dwarf_extensions = 0;
141 /* Command-line argc and argv. These variables are global
142 since they are imported in back_end.adb. */
143 unsigned int save_argc;
144 const char **save_argv;
146 /* GNAT argc and argv. */
147 extern int gnat_argc;
148 extern char **gnat_argv;
150 /* Declare functions we use as part of startup. */
151 extern void __gnat_initialize (void *);
152 extern void __gnat_install_SEH_handler (void *);
153 extern void adainit (void);
154 extern void _ada_gnat1drv (void);
156 /* The parser for the language. For us, we process the GNAT tree. */
159 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
163 /* Call the target specific initializations. */
164 __gnat_initialize (NULL);
166 /* ??? Call the SEH initialization routine. This is to workaround
167 a bootstrap path problem. The call below should be removed at some
168 point and the SEH pointer passed to __gnat_initialize() above. */
169 __gnat_install_SEH_handler((void *)seh);
171 /* Call the front-end elaboration procedures. */
174 /* Call the front end. */
177 /* We always have a single compilation unit in Ada. */
178 cgraph_finalize_compilation_unit ();
181 /* Decode all the language specific options that cannot be decoded by GCC.
182 The option decoding phase of GCC calls this routine on the flags that
183 it cannot decode. Return the number of consecutive arguments from ARGV
184 that have been successfully decoded or 0 on failure. */
187 gnat_handle_option (size_t scode, const char *arg, int value)
189 const struct cl_option *option = &cl_options[scode];
190 enum opt_code code = (enum opt_code) scode;
193 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
195 error ("missing argument to \"-%s\"", option->opt_text);
202 q = XNEWVEC (char, sizeof("-I") + strlen (arg));
205 gnat_argv[gnat_argc] = q;
212 /* We save the value of warn_uninitialized, since if they put
213 -Wuninitialized on the command line, we need to generate a
214 warning about not using it without also specifying -O. */
215 if (warn_uninitialized != 1)
216 warn_uninitialized = (value ? 2 : 0);
219 /* These are used in the GCC Makefile. */
220 case OPT_Wmissing_prototypes:
221 case OPT_Wstrict_prototypes:
222 case OPT_Wwrite_strings:
224 case OPT_Wvariadic_macros:
225 case OPT_Wold_style_definition:
226 case OPT_Wmissing_format_attribute:
227 case OPT_Woverlength_strings:
230 /* This is handled by the front-end. */
235 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
239 case OPT_feliminate_unused_debug_types:
240 /* We arrange for post_option to be able to only set the corresponding
241 flag to 1 when explicitly requested by the user. We expect the
242 default flag value to be either 0 or positive, and expose a positive
243 -f as a negative value to post_option. */
244 flag_eliminate_unused_debug_types = -value;
248 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
253 warning (0, "%<-gnat%> misspelled as %<-gant%>");
255 /* ... fall through ... */
258 /* Recopy the switches without the 'gnat' prefix. */
259 gnat_argv[gnat_argc] = XNEWVEC (char, strlen (arg) + 2);
260 gnat_argv[gnat_argc][0] = '-';
261 strcpy (gnat_argv[gnat_argc] + 1, arg);
266 gnat_argv[gnat_argc] = xstrdup ("-O");
268 gnat_argv[gnat_argc] = xstrdup (arg);
273 gnat_dwarf_extensions ++;
283 /* Initialize for option processing. */
286 gnat_init_options (unsigned int argc, const char **argv)
288 /* Initialize gnat_argv with save_argv size. */
289 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
290 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
296 /* Uninitialized really means uninitialized in Ada. */
297 flag_zero_initialized_in_bss = 0;
302 /* Post-switch processing. */
305 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
307 /* Excess precision other than "fast" requires front-end
309 if (flag_excess_precision_cmdline == EXCESS_PRECISION_STANDARD
310 && TARGET_FLT_EVAL_METHOD_NON_DEFAULT)
311 sorry ("-fexcess-precision=standard for Ada");
312 flag_excess_precision_cmdline = EXCESS_PRECISION_FAST;
314 /* ??? The warning machinery is outsmarted by Ada. */
315 warn_unused_parameter = 0;
317 /* No psABI change warnings for Ada. */
320 /* Force eliminate_unused_debug_types to 0 unless an explicit positive
321 -f has been passed. This forces the default to 0 for Ada, which might
322 differ from the common default. */
323 if (flag_eliminate_unused_debug_types < 0)
324 flag_eliminate_unused_debug_types = 1;
326 flag_eliminate_unused_debug_types = 0;
328 /* Reflect the explicit request of DWARF extensions into the common
329 flag for use by later passes. */
330 if (write_symbols == DWARF2_DEBUG)
331 use_gnu_debug_info_extensions = gnat_dwarf_extensions > 0;
336 /* Here is the function to handle the compiler error processing in GCC. */
339 internal_error_function (const char *msgid, va_list *ap)
342 char *buffer, *p, *loc;
343 String_Template temp, temp_loc;
344 Fat_Pointer fp, fp_loc;
347 /* Reset the pretty-printer. */
348 pp_clear_output_area (global_dc->printer);
350 /* Format the message into the pretty-printer. */
351 tinfo.format_spec = msgid;
353 tinfo.err_no = errno;
354 pp_format_verbatim (global_dc->printer, &tinfo);
356 /* Extract a (writable) pointer to the formatted text. */
357 buffer = xstrdup (pp_formatted_text (global_dc->printer));
359 /* Go up to the first newline. */
360 for (p = buffer; *p; p++)
368 temp.High_Bound = p - buffer;
372 s = expand_location (input_location);
373 if (flag_show_column && s.column != 0)
374 asprintf (&loc, "%s:%d:%d", s.file, s.line, s.column);
376 asprintf (&loc, "%s:%d", s.file, s.line);
377 temp_loc.Low_Bound = 1;
378 temp_loc.High_Bound = strlen (loc);
379 fp_loc.Bounds = &temp_loc;
382 Current_Error_Node = error_gnat_node;
383 Compiler_Abort (fp, -1, fp_loc);
386 /* Perform all the initialization steps that are language-specific. */
391 /* Performs whatever initialization steps needed by the language-dependent
393 gnat_init_decl_processing ();
395 /* Add the input filename as the last argument. */
396 if (main_input_filename)
398 gnat_argv[gnat_argc] = xstrdup (main_input_filename);
400 gnat_argv[gnat_argc] = NULL;
403 global_dc->internal_error = &internal_error_function;
405 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
406 internal_reference_types ();
411 /* If we are using the GCC mechanism to process exception handling, we
412 have to register the personality routine for Ada and to initialize
413 various language dependent hooks. */
416 gnat_init_gcc_eh (void)
418 #ifdef DWARF2_UNWIND_INFO
419 /* lang_dependent_init already called dwarf2out_frame_init if true. */
420 int dwarf2out_frame_initialized = dwarf2out_do_frame ();
423 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
424 though. This could for instance lead to the emission of tables with
425 references to symbols (such as the Ada eh personality routine) within
426 libraries we won't link against. */
427 if (No_Exception_Handlers_Set ())
430 /* Tell GCC we are handling cleanup actions through exception propagation.
431 This opens possibilities that we don't take advantage of yet, but is
432 nonetheless necessary to ensure that fixup code gets assigned to the
433 right exception regions. */
434 using_eh_for_cleanups ();
436 eh_personality_libfunc = init_one_libfunc (USING_SJLJ_EXCEPTIONS
437 ? "__gnat_eh_personality_sj"
438 : "__gnat_eh_personality");
439 lang_eh_type_covers = gnat_eh_type_covers;
440 lang_eh_runtime_type = gnat_return_tree;
441 default_init_unwind_resume_libfunc ();
443 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
444 the generation of the necessary exception runtime tables. The second one
445 is useful for two reasons: 1/ we map some asynchronous signals like SEGV
446 to exceptions, so we need to ensure that the insns which can lead to such
447 signals are correctly attached to the exception region they pertain to,
448 2/ Some calls to pure subprograms are handled as libcall blocks and then
449 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
450 We should not let this be since it is possible for such calls to actually
453 flag_non_call_exceptions = 1;
456 #ifdef DWARF2_UNWIND_INFO
457 if (!dwarf2out_frame_initialized && dwarf2out_do_frame ())
458 dwarf2out_frame_init ();
462 /* Print language-specific items in declaration NODE. */
465 gnat_print_decl (FILE *file, tree node, int indent)
467 switch (TREE_CODE (node))
470 print_node (file, "const_corresponding_var",
471 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
475 print_node (file, "original_field", DECL_ORIGINAL_FIELD (node),
480 print_node (file, "renamed_object", DECL_RENAMED_OBJECT (node),
489 /* Print language-specific items in type NODE. */
492 gnat_print_type (FILE *file, tree node, int indent)
494 switch (TREE_CODE (node))
497 print_node (file, "ci_co_list", TYPE_CI_CO_LIST (node), indent + 4);
501 if (TYPE_MODULAR_P (node))
502 print_node_brief (file, "modulus", TYPE_MODULUS (node), indent + 4);
503 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
504 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
506 else if (TYPE_VAX_FLOATING_POINT_P (node))
509 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
511 /* ... fall through ... */
515 print_node_brief (file, "RM size", TYPE_RM_SIZE (node), indent + 4);
519 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
523 if (TYPE_IS_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
524 print_node (file, "unconstrained array",
525 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
527 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
531 case QUAL_UNION_TYPE:
532 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
540 /* Return the name to be printed for DECL. */
543 gnat_printable_name (tree decl, int verbosity)
545 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
546 char *ada_name = (char *) ggc_alloc (strlen (coded_name) * 2 + 60);
548 __gnat_decode (coded_name, ada_name, 0);
550 if (verbosity == 2 && !DECL_IS_BUILTIN (decl))
552 Set_Identifier_Casing (ada_name, DECL_SOURCE_FILE (decl));
553 return ggc_strdup (Name_Buffer);
559 /* Return the name to be used in DWARF debug info for DECL. */
562 gnat_dwarf_name (tree decl, int verbosity ATTRIBUTE_UNUSED)
564 gcc_assert (DECL_P (decl));
565 return (const char *) IDENTIFIER_POINTER (DECL_NAME (decl));
568 /* Do nothing (return the tree node passed). */
571 gnat_return_tree (tree t)
576 /* Return true if type A catches type B. Callback for flow analysis from
577 the exception handling part of the back-end. */
580 gnat_eh_type_covers (tree a, tree b)
582 /* a catches b if they represent the same exception id or if a
585 ??? integer_zero_node for "others" is hardwired in too many places
587 return (a == b || a == integer_zero_node);
590 /* Get the alias set corresponding to a type or expression. */
592 static alias_set_type
593 gnat_get_alias_set (tree type)
595 /* If this is a padding type, use the type of the first field. */
596 if (TREE_CODE (type) == RECORD_TYPE
597 && TYPE_IS_PADDING_P (type))
598 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
600 /* If the type is an unconstrained array, use the type of the
601 self-referential array we make. */
602 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
604 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
606 /* If the type can alias any other types, return the alias set 0. */
607 else if (TYPE_P (type)
608 && TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (type)))
614 /* GNU_TYPE is a type. Return its maximum size in bytes, if known,
615 as a constant when possible. */
618 gnat_type_max_size (const_tree gnu_type)
620 /* First see what we can get from TYPE_SIZE_UNIT, which might not
621 be constant even for simple expressions if it has already been
622 elaborated and possibly replaced by a VAR_DECL. */
623 tree max_unitsize = max_size (TYPE_SIZE_UNIT (gnu_type), true);
625 /* If we don't have a constant, see what we can get from TYPE_ADA_SIZE,
626 which should stay untouched. */
627 if (!host_integerp (max_unitsize, 1)
628 && (TREE_CODE (gnu_type) == RECORD_TYPE
629 || TREE_CODE (gnu_type) == UNION_TYPE
630 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
631 && TYPE_ADA_SIZE (gnu_type))
633 tree max_adasize = max_size (TYPE_ADA_SIZE (gnu_type), true);
635 /* If we have succeeded in finding a constant, round it up to the
636 type's alignment and return the result in units. */
637 if (host_integerp (max_adasize, 1))
639 = size_binop (CEIL_DIV_EXPR,
640 round_up (max_adasize, TYPE_ALIGN (gnu_type)),
647 /* GNU_TYPE is a type. Determine if it should be passed by reference by
651 default_pass_by_ref (tree gnu_type)
653 /* We pass aggregates by reference if they are sufficiently large. The
654 choice of constant here is somewhat arbitrary. We also pass by
655 reference if the target machine would either pass or return by
656 reference. Strictly speaking, we need only check the return if this
657 is an In Out parameter, but it's probably best to err on the side of
658 passing more things by reference. */
660 if (pass_by_reference (NULL, TYPE_MODE (gnu_type), gnu_type, 1))
663 if (targetm.calls.return_in_memory (gnu_type, NULL_TREE))
666 if (AGGREGATE_TYPE_P (gnu_type)
667 && (!host_integerp (TYPE_SIZE (gnu_type), 1)
668 || 0 < compare_tree_int (TYPE_SIZE (gnu_type),
669 8 * TYPE_ALIGN (gnu_type))))
675 /* GNU_TYPE is the type of a subprogram parameter. Determine from the type if
676 it should be passed by reference. */
679 must_pass_by_ref (tree gnu_type)
681 /* We pass only unconstrained objects, those required by the language
682 to be passed by reference, and objects of variable size. The latter
683 is more efficient, avoids problems with variable size temporaries,
684 and does not produce compatibility problems with C, since C does
685 not have such objects. */
686 return (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
687 || (AGGREGATE_TYPE_P (gnu_type) && TYPE_BY_REFERENCE_P (gnu_type))
688 || (TYPE_SIZE (gnu_type)
689 && TREE_CODE (TYPE_SIZE (gnu_type)) != INTEGER_CST));
692 /* This function is called by the front end to enumerate all the supported
693 modes for the machine. We pass a function which is called back with
694 the following integer parameters:
696 FLOAT_P nonzero if this represents a floating-point mode
697 COMPLEX_P nonzero is this represents a complex mode
698 COUNT count of number of items, nonzero for vector mode
699 PRECISION number of bits in data representation
700 MANTISSA number of bits in mantissa, if FP and known, else zero.
701 SIZE number of bits used to store data
702 ALIGN number of bits to which mode is aligned. */
705 enumerate_modes (void (*f) (int, int, int, int, int, int, unsigned int))
709 for (i = 0; i < NUM_MACHINE_MODES; i++)
717 enum machine_mode inner_mode = i;
719 switch (GET_MODE_CLASS (i))
726 case MODE_COMPLEX_INT:
728 inner_mode = GET_MODE_INNER (i);
730 case MODE_COMPLEX_FLOAT:
733 inner_mode = GET_MODE_INNER (i);
735 case MODE_VECTOR_INT:
737 inner_mode = GET_MODE_INNER (i);
739 case MODE_VECTOR_FLOAT:
742 inner_mode = GET_MODE_INNER (i);
748 /* Skip this mode if it's one the front end doesn't need to know about
749 (e.g., the CC modes) or if there is no add insn for that mode (or
750 any wider mode), meaning it is not supported by the hardware. If
751 this a complex or vector mode, we care about the inner mode. */
752 for (j = inner_mode; j != VOIDmode; j = GET_MODE_WIDER_MODE (j))
753 if (optab_handler (add_optab, j)->insn_code != CODE_FOR_nothing)
758 const struct real_format *fmt = REAL_MODE_FORMAT (inner_mode);
763 if (!skip_p && j != VOIDmode)
764 (*f) (float_p, complex_p, vector_p ? GET_MODE_NUNITS (i) : 0,
765 GET_MODE_BITSIZE (i), mantissa,
766 GET_MODE_SIZE (i) * BITS_PER_UNIT, GET_MODE_ALIGNMENT (i));
770 /* Return the size of the FP mode with precision PREC. */
773 fp_prec_to_size (int prec)
775 enum machine_mode mode;
777 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
778 mode = GET_MODE_WIDER_MODE (mode))
779 if (GET_MODE_PRECISION (mode) == prec)
780 return GET_MODE_BITSIZE (mode);
785 /* Return the precision of the FP mode with size SIZE. */
788 fp_size_to_prec (int size)
790 enum machine_mode mode;
792 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
793 mode = GET_MODE_WIDER_MODE (mode))
794 if (GET_MODE_BITSIZE (mode) == size)
795 return GET_MODE_PRECISION (mode);