1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2010, 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"
41 #include "langhooks.h"
42 #include "langhooks-def.h"
46 #include "function.h" /* For pass_by_reference. */
47 #include "except.h" /* For USING_SJLJ_EXCEPTIONS. */
50 #include "adadecode.h"
64 static bool gnat_init (void);
65 static unsigned int gnat_init_options (unsigned int, const char **);
66 static int gnat_handle_option (size_t, const char *, int, int);
67 static bool gnat_post_options (const char **);
68 static alias_set_type gnat_get_alias_set (tree);
69 static void gnat_print_decl (FILE *, tree, int);
70 static void gnat_print_type (FILE *, tree, int);
71 static const char *gnat_printable_name (tree, int);
72 static const char *gnat_dwarf_name (tree, int);
73 static tree gnat_return_tree (tree);
74 static void gnat_parse_file (int);
75 static void internal_error_function (diagnostic_context *,
76 const char *, va_list *);
77 static tree gnat_type_max_size (const_tree);
78 static void gnat_get_subrange_bounds (const_tree, tree *, tree *);
79 static tree gnat_eh_personality (void);
81 /* Definitions for our language-specific hooks. */
83 #undef LANG_HOOKS_NAME
84 #define LANG_HOOKS_NAME "GNU Ada"
85 #undef LANG_HOOKS_IDENTIFIER_SIZE
86 #define LANG_HOOKS_IDENTIFIER_SIZE sizeof (struct tree_identifier)
87 #undef LANG_HOOKS_INIT
88 #define LANG_HOOKS_INIT gnat_init
89 #undef LANG_HOOKS_INIT_OPTIONS
90 #define LANG_HOOKS_INIT_OPTIONS gnat_init_options
91 #undef LANG_HOOKS_HANDLE_OPTION
92 #define LANG_HOOKS_HANDLE_OPTION gnat_handle_option
93 #undef LANG_HOOKS_POST_OPTIONS
94 #define LANG_HOOKS_POST_OPTIONS gnat_post_options
95 #undef LANG_HOOKS_PARSE_FILE
96 #define LANG_HOOKS_PARSE_FILE gnat_parse_file
97 #undef LANG_HOOKS_HASH_TYPES
98 #define LANG_HOOKS_HASH_TYPES false
99 #undef LANG_HOOKS_GETDECLS
100 #define LANG_HOOKS_GETDECLS lhd_return_null_tree_v
101 #undef LANG_HOOKS_PUSHDECL
102 #define LANG_HOOKS_PUSHDECL gnat_return_tree
103 #undef LANG_HOOKS_WRITE_GLOBALS
104 #define LANG_HOOKS_WRITE_GLOBALS gnat_write_global_declarations
105 #undef LANG_HOOKS_GET_ALIAS_SET
106 #define LANG_HOOKS_GET_ALIAS_SET gnat_get_alias_set
107 #undef LANG_HOOKS_PRINT_DECL
108 #define LANG_HOOKS_PRINT_DECL gnat_print_decl
109 #undef LANG_HOOKS_PRINT_TYPE
110 #define LANG_HOOKS_PRINT_TYPE gnat_print_type
111 #undef LANG_HOOKS_TYPE_MAX_SIZE
112 #define LANG_HOOKS_TYPE_MAX_SIZE gnat_type_max_size
113 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
114 #define LANG_HOOKS_DECL_PRINTABLE_NAME gnat_printable_name
115 #undef LANG_HOOKS_DWARF_NAME
116 #define LANG_HOOKS_DWARF_NAME gnat_dwarf_name
117 #undef LANG_HOOKS_GIMPLIFY_EXPR
118 #define LANG_HOOKS_GIMPLIFY_EXPR gnat_gimplify_expr
119 #undef LANG_HOOKS_TYPE_FOR_MODE
120 #define LANG_HOOKS_TYPE_FOR_MODE gnat_type_for_mode
121 #undef LANG_HOOKS_TYPE_FOR_SIZE
122 #define LANG_HOOKS_TYPE_FOR_SIZE gnat_type_for_size
123 #undef LANG_HOOKS_TYPES_COMPATIBLE_P
124 #define LANG_HOOKS_TYPES_COMPATIBLE_P gnat_types_compatible_p
125 #undef LANG_HOOKS_GET_SUBRANGE_BOUNDS
126 #define LANG_HOOKS_GET_SUBRANGE_BOUNDS gnat_get_subrange_bounds
127 #undef LANG_HOOKS_ATTRIBUTE_TABLE
128 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
129 #undef LANG_HOOKS_BUILTIN_FUNCTION
130 #define LANG_HOOKS_BUILTIN_FUNCTION gnat_builtin_function
131 #undef LANG_HOOKS_EH_PERSONALITY
132 #define LANG_HOOKS_EH_PERSONALITY gnat_eh_personality
133 #undef LANG_HOOKS_DEEP_UNSHARING
134 #define LANG_HOOKS_DEEP_UNSHARING true
136 struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
138 /* This symbol needs to be defined for the front-end. */
139 void *callgraph_info_file = NULL;
141 /* How much we want of our DWARF extensions. Some of our dwarf+ extensions
142 are incompatible with regular GDB versions, so we must make sure to only
143 produce them on explicit request. This is eventually reflected into the
144 use_gnu_debug_info_extensions common flag for later processing. */
145 static int gnat_dwarf_extensions = 0;
147 /* Command-line argc and argv. These variables are global
148 since they are imported in back_end.adb. */
149 unsigned int save_argc;
150 const char **save_argv;
152 /* GNAT argc and argv. */
153 extern int gnat_argc;
154 extern char **gnat_argv;
156 /* Declare functions we use as part of startup. */
157 extern void __gnat_initialize (void *);
158 extern void __gnat_install_SEH_handler (void *);
159 extern void adainit (void);
160 extern void _ada_gnat1drv (void);
162 /* The parser for the language. For us, we process the GNAT tree. */
165 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
169 /* Call the target specific initializations. */
170 __gnat_initialize (NULL);
172 /* ??? Call the SEH initialization routine. This is to workaround
173 a bootstrap path problem. The call below should be removed at some
174 point and the SEH pointer passed to __gnat_initialize() above. */
175 __gnat_install_SEH_handler((void *)seh);
177 /* Call the front-end elaboration procedures. */
180 /* Call the front end. */
184 /* Decode all the language specific options that cannot be decoded by GCC.
185 The option decoding phase of GCC calls this routine on the flags that
186 it cannot decode. Return the number of consecutive arguments from ARGV
187 that have been successfully decoded or 0 on failure. */
190 gnat_handle_option (size_t scode, const char *arg, int value,
191 int kind ATTRIBUTE_UNUSED)
193 const struct cl_option *option = &cl_options[scode];
194 enum opt_code code = (enum opt_code) scode;
197 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
199 error ("missing argument to \"-%s\"", option->opt_text);
206 q = XNEWVEC (char, sizeof("-I") + strlen (arg));
209 gnat_argv[gnat_argc] = q;
215 warn_uninitialized = value;
218 /* These are used in the GCC Makefile. */
219 case OPT_Wmissing_prototypes:
220 case OPT_Wstrict_prototypes:
221 case OPT_Wwrite_strings:
223 case OPT_Wvariadic_macros:
224 case OPT_Wold_style_definition:
225 case OPT_Wmissing_format_attribute:
226 case OPT_Woverlength_strings:
229 /* This is handled by the front-end. */
234 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
238 case OPT_feliminate_unused_debug_types:
239 /* We arrange for post_option to be able to only set the corresponding
240 flag to 1 when explicitly requested by the user. We expect the
241 default flag value to be either 0 or positive, and expose a positive
242 -f as a negative value to post_option. */
243 flag_eliminate_unused_debug_types = -value;
247 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
252 warning (0, "%<-gnat%> misspelled as %<-gant%>");
254 /* ... fall through ... */
257 /* Recopy the switches without the 'gnat' prefix. */
258 gnat_argv[gnat_argc] = XNEWVEC (char, strlen (arg) + 2);
259 gnat_argv[gnat_argc][0] = '-';
260 strcpy (gnat_argv[gnat_argc] + 1, arg);
265 gnat_argv[gnat_argc] = xstrdup ("-O");
267 gnat_argv[gnat_argc] = xstrdup (arg);
272 gnat_dwarf_extensions = 1;
282 /* Initialize for option processing. */
285 gnat_init_options (unsigned int argc, const char **argv)
287 /* Initialize gnat_argv with save_argv size. */
288 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
289 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
295 /* Uninitialized really means uninitialized in Ada. */
296 flag_zero_initialized_in_bss = 0;
301 /* Post-switch processing. */
304 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
306 /* Excess precision other than "fast" requires front-end
308 if (flag_excess_precision_cmdline == EXCESS_PRECISION_STANDARD
309 && TARGET_FLT_EVAL_METHOD_NON_DEFAULT)
310 sorry ("-fexcess-precision=standard for Ada");
311 flag_excess_precision_cmdline = EXCESS_PRECISION_FAST;
313 /* ??? The warning machinery is outsmarted by Ada. */
314 warn_unused_parameter = 0;
316 /* No psABI change warnings for Ada. */
319 /* Force eliminate_unused_debug_types to 0 unless an explicit positive
320 -f has been passed. This forces the default to 0 for Ada, which might
321 differ from the common default. */
322 if (flag_eliminate_unused_debug_types < 0)
323 flag_eliminate_unused_debug_types = 1;
325 flag_eliminate_unused_debug_types = 0;
327 /* Reflect the explicit request of DWARF extensions into the common
328 flag for use by later passes. */
329 if (write_symbols == DWARF2_DEBUG)
330 use_gnu_debug_info_extensions = gnat_dwarf_extensions > 0;
335 /* Here is the function to handle the compiler error processing in GCC. */
338 internal_error_function (diagnostic_context *context,
339 const char *msgid, va_list *ap)
342 char *buffer, *p, *loc;
343 String_Template temp, temp_loc;
344 Fat_Pointer fp, fp_loc;
347 /* Warn if plugins present. */
350 /* Reset the pretty-printer. */
351 pp_clear_output_area (context->printer);
353 /* Format the message into the pretty-printer. */
354 tinfo.format_spec = msgid;
356 tinfo.err_no = errno;
357 pp_format_verbatim (context->printer, &tinfo);
359 /* Extract a (writable) pointer to the formatted text. */
360 buffer = xstrdup (pp_formatted_text (context->printer));
362 /* Go up to the first newline. */
363 for (p = buffer; *p; p++)
371 temp.High_Bound = p - buffer;
375 s = expand_location (input_location);
376 if (context->show_column && s.column != 0)
377 asprintf (&loc, "%s:%d:%d", s.file, s.line, s.column);
379 asprintf (&loc, "%s:%d", s.file, s.line);
380 temp_loc.Low_Bound = 1;
381 temp_loc.High_Bound = strlen (loc);
382 fp_loc.Bounds = &temp_loc;
385 Current_Error_Node = error_gnat_node;
386 Compiler_Abort (fp, -1, fp_loc);
389 /* Perform all the initialization steps that are language-specific. */
394 /* Do little here, most of the standard declarations are set up after the
395 front-end has been run. Use the same `char' as C, this doesn't really
396 matter since we'll use the explicit `unsigned char' for Character. */
397 build_common_tree_nodes (flag_signed_char);
399 /* In Ada, we use the unsigned type corresponding to the width of Pmode as
400 SIZETYPE. In most cases when ptr_mode and Pmode differ, C will use the
401 width of ptr_mode for SIZETYPE, but we get better code using the width
402 of Pmode. Note that, although we manipulate negative offsets for some
403 internal constructs and rely on compile time overflow detection in size
404 computations, using unsigned types for SIZETYPEs is fine since they are
405 treated specially by the middle-end, in particular sign-extended. */
406 size_type_node = gnat_type_for_mode (Pmode, 1);
407 set_sizetype (size_type_node);
408 TYPE_NAME (sizetype) = get_identifier ("size_type");
410 /* In Ada, we use an unsigned 8-bit type for the default boolean type. */
411 boolean_type_node = make_unsigned_type (8);
412 TREE_SET_CODE (boolean_type_node, BOOLEAN_TYPE);
413 SET_TYPE_RM_MAX_VALUE (boolean_type_node,
414 build_int_cst (boolean_type_node, 1));
415 SET_TYPE_RM_SIZE (boolean_type_node, bitsize_int (1));
417 build_common_tree_nodes_2 (0);
418 sbitsize_one_node = sbitsize_int (1);
419 sbitsize_unit_node = sbitsize_int (BITS_PER_UNIT);
420 boolean_true_node = TYPE_MAX_VALUE (boolean_type_node);
422 ptr_void_type_node = build_pointer_type (void_type_node);
424 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
425 internal_reference_types ();
427 /* Add the input filename as the last argument. */
428 if (main_input_filename)
430 gnat_argv[gnat_argc] = xstrdup (main_input_filename);
432 gnat_argv[gnat_argc] = NULL;
435 /* Register our internal error function. */
436 global_dc->internal_error = &internal_error_function;
441 /* If we are using the GCC mechanism to process exception handling, we
442 have to register the personality routine for Ada and to initialize
443 various language dependent hooks. */
446 gnat_init_gcc_eh (void)
448 #ifdef DWARF2_UNWIND_INFO
449 /* lang_dependent_init already called dwarf2out_frame_init if true. */
450 int dwarf2out_frame_initialized = dwarf2out_do_frame ();
453 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
454 though. This could for instance lead to the emission of tables with
455 references to symbols (such as the Ada eh personality routine) within
456 libraries we won't link against. */
457 if (No_Exception_Handlers_Set ())
460 /* Tell GCC we are handling cleanup actions through exception propagation.
461 This opens possibilities that we don't take advantage of yet, but is
462 nonetheless necessary to ensure that fixup code gets assigned to the
463 right exception regions. */
464 using_eh_for_cleanups ();
466 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
467 the generation of the necessary exception tables. The second one is
468 useful for two reasons: 1/ we map some asynchronous signals like SEGV to
469 exceptions, so we need to ensure that the insns which can lead to such
470 signals are correctly attached to the exception region they pertain to,
471 2/ Some calls to pure subprograms are handled as libcall blocks and then
472 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
473 We should not let this be since it is possible for such calls to actually
476 flag_non_call_exceptions = 1;
479 #ifdef DWARF2_UNWIND_INFO
480 if (!dwarf2out_frame_initialized && dwarf2out_do_frame ())
481 dwarf2out_frame_init ();
485 /* Print language-specific items in declaration NODE. */
488 gnat_print_decl (FILE *file, tree node, int indent)
490 switch (TREE_CODE (node))
493 print_node (file, "corresponding var",
494 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
498 print_node (file, "original field", DECL_ORIGINAL_FIELD (node),
503 print_node (file, "renamed object", DECL_RENAMED_OBJECT (node),
512 /* Print language-specific items in type NODE. */
515 gnat_print_type (FILE *file, tree node, int indent)
517 switch (TREE_CODE (node))
520 print_node (file, "ci/co list", TYPE_CI_CO_LIST (node), indent + 4);
524 if (TYPE_MODULAR_P (node))
525 print_node_brief (file, "modulus", TYPE_MODULUS (node), indent + 4);
526 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
527 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
529 else if (TYPE_VAX_FLOATING_POINT_P (node))
532 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
534 /* ... fall through ... */
538 print_node_brief (file, "RM size", TYPE_RM_SIZE (node), indent + 4);
540 /* ... fall through ... */
543 print_node_brief (file, "RM min", TYPE_RM_MIN_VALUE (node), indent + 4);
544 print_node_brief (file, "RM max", TYPE_RM_MAX_VALUE (node), indent + 4);
548 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
552 print_node (file,"representative array",
553 TYPE_REPRESENTATIVE_ARRAY (node), indent + 4);
557 if (TYPE_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
558 print_node (file, "unconstrained array",
559 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
561 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
565 case QUAL_UNION_TYPE:
566 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
574 /* Return the name to be printed for DECL. */
577 gnat_printable_name (tree decl, int verbosity)
579 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
580 char *ada_name = (char *) ggc_alloc_atomic (strlen (coded_name) * 2 + 60);
582 __gnat_decode (coded_name, ada_name, 0);
584 if (verbosity == 2 && !DECL_IS_BUILTIN (decl))
586 Set_Identifier_Casing (ada_name, DECL_SOURCE_FILE (decl));
587 return ggc_strdup (Name_Buffer);
593 /* Return the name to be used in DWARF debug info for DECL. */
596 gnat_dwarf_name (tree decl, int verbosity ATTRIBUTE_UNUSED)
598 gcc_assert (DECL_P (decl));
599 return (const char *) IDENTIFIER_POINTER (DECL_NAME (decl));
602 /* Do nothing (return the tree node passed). */
605 gnat_return_tree (tree t)
610 /* Get the alias set corresponding to a type or expression. */
612 static alias_set_type
613 gnat_get_alias_set (tree type)
615 /* If this is a padding type, use the type of the first field. */
616 if (TYPE_IS_PADDING_P (type))
617 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
619 /* If the type is an unconstrained array, use the type of the
620 self-referential array we make. */
621 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
623 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
625 /* If the type can alias any other types, return the alias set 0. */
626 else if (TYPE_P (type)
627 && TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (type)))
633 /* GNU_TYPE is a type. Return its maximum size in bytes, if known,
634 as a constant when possible. */
637 gnat_type_max_size (const_tree gnu_type)
639 /* First see what we can get from TYPE_SIZE_UNIT, which might not
640 be constant even for simple expressions if it has already been
641 elaborated and possibly replaced by a VAR_DECL. */
642 tree max_unitsize = max_size (TYPE_SIZE_UNIT (gnu_type), true);
644 /* If we don't have a constant, see what we can get from TYPE_ADA_SIZE,
645 which should stay untouched. */
646 if (!host_integerp (max_unitsize, 1)
647 && (TREE_CODE (gnu_type) == RECORD_TYPE
648 || TREE_CODE (gnu_type) == UNION_TYPE
649 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
650 && TYPE_ADA_SIZE (gnu_type))
652 tree max_adasize = max_size (TYPE_ADA_SIZE (gnu_type), true);
654 /* If we have succeeded in finding a constant, round it up to the
655 type's alignment and return the result in units. */
656 if (host_integerp (max_adasize, 1))
658 = size_binop (CEIL_DIV_EXPR,
659 round_up (max_adasize, TYPE_ALIGN (gnu_type)),
666 /* GNU_TYPE is a subtype of an integral type. Set LOWVAL to the low bound
667 and HIGHVAL to the high bound, respectively. */
670 gnat_get_subrange_bounds (const_tree gnu_type, tree *lowval, tree *highval)
672 *lowval = TYPE_MIN_VALUE (gnu_type);
673 *highval = TYPE_MAX_VALUE (gnu_type);
676 /* GNU_TYPE is a type. Determine if it should be passed by reference by
680 default_pass_by_ref (tree gnu_type)
682 /* We pass aggregates by reference if they are sufficiently large. The
683 choice of constant here is somewhat arbitrary. We also pass by
684 reference if the target machine would either pass or return by
685 reference. Strictly speaking, we need only check the return if this
686 is an In Out parameter, but it's probably best to err on the side of
687 passing more things by reference. */
689 if (pass_by_reference (NULL, TYPE_MODE (gnu_type), gnu_type, 1))
692 if (targetm.calls.return_in_memory (gnu_type, NULL_TREE))
695 if (AGGREGATE_TYPE_P (gnu_type)
696 && (!host_integerp (TYPE_SIZE (gnu_type), 1)
697 || 0 < compare_tree_int (TYPE_SIZE (gnu_type),
698 8 * TYPE_ALIGN (gnu_type))))
704 /* GNU_TYPE is the type of a subprogram parameter. Determine from the type if
705 it should be passed by reference. */
708 must_pass_by_ref (tree gnu_type)
710 /* We pass only unconstrained objects, those required by the language
711 to be passed by reference, and objects of variable size. The latter
712 is more efficient, avoids problems with variable size temporaries,
713 and does not produce compatibility problems with C, since C does
714 not have such objects. */
715 return (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
716 || TREE_ADDRESSABLE (gnu_type)
717 || (TYPE_SIZE (gnu_type)
718 && TREE_CODE (TYPE_SIZE (gnu_type)) != INTEGER_CST));
721 /* Return the size of the FP mode with precision PREC. */
724 fp_prec_to_size (int prec)
726 enum machine_mode mode;
728 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
729 mode = GET_MODE_WIDER_MODE (mode))
730 if (GET_MODE_PRECISION (mode) == prec)
731 return GET_MODE_BITSIZE (mode);
736 /* Return the precision of the FP mode with size SIZE. */
739 fp_size_to_prec (int size)
741 enum machine_mode mode;
743 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
744 mode = GET_MODE_WIDER_MODE (mode))
745 if (GET_MODE_BITSIZE (mode) == size)
746 return GET_MODE_PRECISION (mode);
751 static GTY(()) tree gnat_eh_personality_decl;
754 gnat_eh_personality (void)
756 if (!gnat_eh_personality_decl)
757 gnat_eh_personality_decl
758 = build_personality_function (USING_SJLJ_EXCEPTIONS
759 ? "__gnat_eh_personality_sj"
760 : "__gnat_eh_personality");
762 return gnat_eh_personality_decl;
765 #include "gt-ada-misc.h"