1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2007, 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 2, 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 COPYING. If not, write *
19 * to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
20 * Boston, MA 02110-1301, USA. *
22 * As a special exception, if you link this file with other files to *
23 * produce an executable, this file does not by itself cause the resulting *
24 * executable to be covered by the GNU General Public License. This except- *
25 * ion does not however invalidate any other reasons why the executable *
26 * file might be covered by the GNU Public License. *
28 * GNAT was originally developed by the GNAT team at New York University. *
29 * Extensive contributions were provided by Ada Core Technologies Inc. *
31 ****************************************************************************/
33 /* This file contains parts of the compiler that are required for interfacing
34 with GCC but otherwise do nothing and parts of Gigi that need to know
39 #include "coretypes.h"
44 #include "diagnostic.h"
51 #include "tree-inline.h"
52 #include "insn-codes.h"
53 #include "insn-flags.h"
54 #include "insn-config.h"
61 #include "langhooks.h"
62 #include "langhooks-def.h"
78 #include "adadecode.h"
82 extern FILE *asm_out_file;
84 /* The largest alignment, in bits, that is needed for using the widest
86 unsigned int largest_move_alignment;
88 static bool gnat_init (void);
89 static void gnat_finish_incomplete_decl (tree);
90 static unsigned int gnat_init_options (unsigned int, const char **);
91 static int gnat_handle_option (size_t, const char *, int);
92 static bool gnat_post_options (const char **);
93 static alias_set_type gnat_get_alias_set (tree);
94 static void gnat_print_decl (FILE *, tree, int);
95 static void gnat_print_type (FILE *, tree, int);
96 static const char *gnat_printable_name (tree, int);
97 static const char *gnat_dwarf_name (tree, int);
98 static tree gnat_eh_runtime_type (tree);
99 static int gnat_eh_type_covers (tree, tree);
100 static void gnat_parse_file (int);
101 static rtx gnat_expand_expr (tree, rtx, enum machine_mode, int,
103 static void gnat_expand_body (tree);
104 static void internal_error_function (const char *, va_list *);
105 static void gnat_adjust_rli (record_layout_info);
106 static tree gnat_type_max_size (tree);
108 /* Definitions for our language-specific hooks. */
110 #undef LANG_HOOKS_NAME
111 #define LANG_HOOKS_NAME "GNU Ada"
112 #undef LANG_HOOKS_IDENTIFIER_SIZE
113 #define LANG_HOOKS_IDENTIFIER_SIZE sizeof (struct tree_identifier)
114 #undef LANG_HOOKS_INIT
115 #define LANG_HOOKS_INIT gnat_init
116 #undef LANG_HOOKS_INIT_OPTIONS
117 #define LANG_HOOKS_INIT_OPTIONS gnat_init_options
118 #undef LANG_HOOKS_HANDLE_OPTION
119 #define LANG_HOOKS_HANDLE_OPTION gnat_handle_option
120 #undef LANG_HOOKS_POST_OPTIONS
121 #define LANG_HOOKS_POST_OPTIONS gnat_post_options
122 #undef LANG_HOOKS_PARSE_FILE
123 #define LANG_HOOKS_PARSE_FILE gnat_parse_file
124 #undef LANG_HOOKS_HASH_TYPES
125 #define LANG_HOOKS_HASH_TYPES false
126 #undef LANG_HOOKS_GETDECLS
127 #define LANG_HOOKS_GETDECLS lhd_return_null_tree_v
128 #undef LANG_HOOKS_PUSHDECL
129 #define LANG_HOOKS_PUSHDECL lhd_return_tree
130 #undef LANG_HOOKS_WRITE_GLOBALS
131 #define LANG_HOOKS_WRITE_GLOBALS gnat_write_global_declarations
132 #undef LANG_HOOKS_FINISH_INCOMPLETE_DECL
133 #define LANG_HOOKS_FINISH_INCOMPLETE_DECL gnat_finish_incomplete_decl
134 #undef LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS
135 #define LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS true
136 #undef LANG_HOOKS_GET_ALIAS_SET
137 #define LANG_HOOKS_GET_ALIAS_SET gnat_get_alias_set
138 #undef LANG_HOOKS_EXPAND_EXPR
139 #define LANG_HOOKS_EXPAND_EXPR gnat_expand_expr
140 #undef LANG_HOOKS_MARK_ADDRESSABLE
141 #define LANG_HOOKS_MARK_ADDRESSABLE gnat_mark_addressable
142 #undef LANG_HOOKS_PRINT_DECL
143 #define LANG_HOOKS_PRINT_DECL gnat_print_decl
144 #undef LANG_HOOKS_PRINT_TYPE
145 #define LANG_HOOKS_PRINT_TYPE gnat_print_type
146 #undef LANG_HOOKS_TYPE_MAX_SIZE
147 #define LANG_HOOKS_TYPE_MAX_SIZE gnat_type_max_size
148 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
149 #define LANG_HOOKS_DECL_PRINTABLE_NAME gnat_printable_name
150 #undef LANG_HOOKS_DWARF_NAME
151 #define LANG_HOOKS_DWARF_NAME gnat_dwarf_name
152 #undef LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION
153 #define LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION gnat_expand_body
154 #undef LANG_HOOKS_GIMPLIFY_EXPR
155 #define LANG_HOOKS_GIMPLIFY_EXPR gnat_gimplify_expr
156 #undef LANG_HOOKS_TYPE_FOR_MODE
157 #define LANG_HOOKS_TYPE_FOR_MODE gnat_type_for_mode
158 #undef LANG_HOOKS_TYPE_FOR_SIZE
159 #define LANG_HOOKS_TYPE_FOR_SIZE gnat_type_for_size
160 #undef LANG_HOOKS_ATTRIBUTE_TABLE
161 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
162 #undef LANG_HOOKS_BUILTIN_FUNCTION
163 #define LANG_HOOKS_BUILTIN_FUNCTION gnat_builtin_function
165 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
167 /* Tables describing GCC tree codes used only by GNAT.
169 Table indexed by tree code giving a string containing a character
170 classifying the tree code. Possibilities are
171 t, d, s, c, r, <, 1 and 2. See cp-tree.def for details. */
173 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
175 const enum tree_code_class tree_code_type[] = {
178 #include "ada-tree.def"
182 /* Table indexed by tree code giving number of expression
183 operands beyond the fixed part of the node structure.
184 Not used for types or decls. */
186 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
188 const unsigned char tree_code_length[] = {
191 #include "ada-tree.def"
195 /* Names of tree components.
196 Used for printing out the tree and error messages. */
197 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
199 const char *const tree_code_name[] = {
202 #include "ada-tree.def"
206 /* Command-line argc and argv.
207 These variables are global, since they are imported and used in
210 unsigned int save_argc;
211 const char **save_argv;
213 /* gnat standard argc argv */
215 extern int gnat_argc;
216 extern char **gnat_argv;
219 /* Declare functions we use as part of startup. */
220 extern void __gnat_initialize (void *);
221 extern void __gnat_install_SEH_handler (void *);
222 extern void adainit (void);
223 extern void _ada_gnat1drv (void);
225 /* The parser for the language. For us, we process the GNAT tree. */
228 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
232 /* Call the target specific initializations. */
233 __gnat_initialize (NULL);
235 /* ??? Call the SEH initialization routine. This is to workaround
236 a bootstrap path problem. The call below should be removed at some
237 point and the SEH pointer passed to __gnat_initialize() above. */
238 __gnat_install_SEH_handler((void *)seh);
240 /* Call the front-end elaboration procedures. */
243 /* Call the front end. */
246 /* We always have a single compilation unit in Ada. */
247 cgraph_finalize_compilation_unit ();
250 /* Decode all the language specific options that cannot be decoded by GCC.
251 The option decoding phase of GCC calls this routine on the flags that
252 it cannot decode. This routine returns the number of consecutive arguments
253 from ARGV that it successfully decoded; 0 indicates failure. */
256 gnat_handle_option (size_t scode, const char *arg, int value ATTRIBUTE_UNUSED)
258 const struct cl_option *option = &cl_options[scode];
259 enum opt_code code = (enum opt_code) scode;
262 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
264 error ("missing argument to \"-%s\"", option->opt_text);
274 q = xmalloc (sizeof("-I") + strlen (arg));
277 gnat_argv[gnat_argc] = q;
281 /* All front ends are expected to accept this. */
283 /* These are used in the GCC Makefile. */
284 case OPT_Wmissing_prototypes:
285 case OPT_Wstrict_prototypes:
286 case OPT_Wwrite_strings:
288 case OPT_Wvariadic_macros:
289 case OPT_Wold_style_definition:
290 case OPT_Wmissing_format_attribute:
291 case OPT_Woverlength_strings:
294 /* This is handled by the front-end. */
299 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
303 case OPT_feliminate_unused_debug_types:
304 /* We arrange for post_option to be able to only set the corresponding
305 flag to 1 when explicitely requested by the user. We expect the
306 default flag value to be either 0 or positive, and expose a positive
307 -f as a negative value to post_option. */
308 flag_eliminate_unused_debug_types = -value;
312 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
317 warning (0, "%<-gnat%> misspelled as %<-gant%>");
319 /* ... fall through ... */
322 /* Recopy the switches without the 'gnat' prefix. */
323 gnat_argv[gnat_argc] = xmalloc (strlen (arg) + 2);
324 gnat_argv[gnat_argc][0] = '-';
325 strcpy (gnat_argv[gnat_argc] + 1, arg);
330 gnat_argv[gnat_argc] = xstrdup ("-O");
332 gnat_argv[gnat_argc] = xstrdup (arg);
340 /* Initialize for option processing. */
343 gnat_init_options (unsigned int argc, const char **argv)
345 /* Initialize gnat_argv with save_argv size. */
346 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
347 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
353 /* Uninitialized really means uninitialized in Ada. */
354 flag_zero_initialized_in_bss = 0;
359 /* Post-switch processing. */
362 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
364 flag_inline_trees = 1;
368 if (flag_inline_functions)
369 flag_inline_trees = 2;
371 /* Force eliminate_unused_debug_types to 0 unless an explicit positive
372 -f has been passed. This forces the default to 0 for Ada, which might
373 differ from the common default. */
374 if (flag_eliminate_unused_debug_types < 0)
375 flag_eliminate_unused_debug_types = 1;
377 flag_eliminate_unused_debug_types = 0;
382 /* Here is the function to handle the compiler error processing in GCC. */
385 internal_error_function (const char *msgid, va_list *ap)
388 char *buffer, *p, *loc;
389 String_Template temp, temp_loc;
390 Fat_Pointer fp, fp_loc;
393 /* Reset the pretty-printer. */
394 pp_clear_output_area (global_dc->printer);
396 /* Format the message into the pretty-printer. */
397 tinfo.format_spec = msgid;
399 tinfo.err_no = errno;
400 pp_format_verbatim (global_dc->printer, &tinfo);
402 /* Extract a (writable) pointer to the formatted text. */
403 buffer = (char*) pp_formatted_text (global_dc->printer);
405 /* Go up to the first newline. */
406 for (p = buffer; *p; p++)
414 temp.High_Bound = p - buffer;
418 s = expand_location (input_location);
419 #ifdef USE_MAPPED_LOCATION
420 if (flag_show_column && s.column != 0)
421 asprintf (&loc, "%s:%d:%d", s.file, s.line, s.column);
424 asprintf (&loc, "%s:%d", s.file, s.line);
425 temp_loc.Low_Bound = 1;
426 temp_loc.High_Bound = strlen (loc);
427 fp_loc.Bounds = &temp_loc;
430 Current_Error_Node = error_gnat_node;
431 Compiler_Abort (fp, -1, fp_loc);
434 /* Perform all the initialization steps that are language-specific. */
439 /* Initialize translations and the outer statement group. */
440 gnat_init_stmt_group ();
442 /* Performs whatever initialization steps needed by the language-dependent
444 gnat_init_decl_processing ();
446 /* Add the input filename as the last argument. */
447 gnat_argv[gnat_argc] = (char *) main_input_filename;
449 gnat_argv[gnat_argc] = 0;
451 global_dc->internal_error = &internal_error_function;
453 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
454 internal_reference_types ();
456 set_lang_adjust_rli (gnat_adjust_rli);
461 /* This function is called indirectly from toplev.c to handle incomplete
462 declarations, i.e. VAR_DECL nodes whose DECL_SIZE is zero. To be precise,
463 compile_file in toplev.c makes an indirect call through the function pointer
464 incomplete_decl_finalize_hook which is initialized to this routine in
465 init_decl_processing. */
468 gnat_finish_incomplete_decl (tree dont_care ATTRIBUTE_UNUSED)
473 /* Compute the alignment of the largest mode that can be used for copying
477 gnat_compute_largest_alignment (void)
479 enum machine_mode mode;
481 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
482 mode = GET_MODE_WIDER_MODE (mode))
483 if (optab_handler (mov_optab, mode)->insn_code != CODE_FOR_nothing)
484 largest_move_alignment = MIN (BIGGEST_ALIGNMENT,
485 MAX (largest_move_alignment,
486 GET_MODE_ALIGNMENT (mode)));
489 /* If we are using the GCC mechanism to process exception handling, we
490 have to register the personality routine for Ada and to initialize
491 various language dependent hooks. */
494 gnat_init_gcc_eh (void)
496 #ifdef DWARF2_UNWIND_INFO
497 /* lang_dependent_init already called dwarf2out_frame_init if true. */
498 int dwarf2out_frame_initialized = dwarf2out_do_frame ();
501 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
502 though. This could for instance lead to the emission of tables with
503 references to symbols (such as the Ada eh personality routine) within
504 libraries we won't link against. */
505 if (No_Exception_Handlers_Set ())
508 /* Tell GCC we are handling cleanup actions through exception propagation.
509 This opens possibilities that we don't take advantage of yet, but is
510 nonetheless necessary to ensure that fixup code gets assigned to the
511 right exception regions. */
512 using_eh_for_cleanups ();
514 eh_personality_libfunc = init_one_libfunc (USING_SJLJ_EXCEPTIONS
515 ? "__gnat_eh_personality_sj"
516 : "__gnat_eh_personality");
517 lang_eh_type_covers = gnat_eh_type_covers;
518 lang_eh_runtime_type = gnat_eh_runtime_type;
519 default_init_unwind_resume_libfunc ();
521 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
522 the generation of the necessary exception runtime tables. The second one
523 is useful for two reasons: 1/ we map some asynchronous signals like SEGV
524 to exceptions, so we need to ensure that the insns which can lead to such
525 signals are correctly attached to the exception region they pertain to,
526 2/ Some calls to pure subprograms are handled as libcall blocks and then
527 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
528 We should not let this be since it is possible for such calls to actually
532 flag_non_call_exceptions = 1;
535 #ifdef DWARF2_UNWIND_INFO
536 if (!dwarf2out_frame_initialized && dwarf2out_do_frame ())
537 dwarf2out_frame_init ();
541 /* Language hooks, first one to print language-specific items in a DECL. */
544 gnat_print_decl (FILE *file, tree node, int indent)
546 switch (TREE_CODE (node))
549 print_node (file, "const_corresponding_var",
550 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
554 print_node (file, "original_field", DECL_ORIGINAL_FIELD (node),
559 print_node (file, "renamed_object", DECL_RENAMED_OBJECT (node),
569 gnat_print_type (FILE *file, tree node, int indent)
571 switch (TREE_CODE (node))
574 print_node (file, "ci_co_list", TYPE_CI_CO_LIST (node), indent + 4);
578 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
582 if (TYPE_MODULAR_P (node))
583 print_node (file, "modulus", TYPE_MODULUS (node), indent + 4);
584 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
585 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
587 else if (TYPE_VAX_FLOATING_POINT_P (node))
590 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
592 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
596 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
600 if (TYPE_IS_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
601 print_node (file, "unconstrained array",
602 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
604 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
608 case QUAL_UNION_TYPE:
609 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
618 gnat_printable_name (tree decl, int verbosity)
620 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
621 char *ada_name = (char *) ggc_alloc (strlen (coded_name) * 2 + 60);
623 __gnat_decode (coded_name, ada_name, 0);
627 Set_Identifier_Casing (ada_name, (char *) DECL_SOURCE_FILE (decl));
628 ada_name = Name_Buffer;
631 return (const char *) ada_name;
635 gnat_dwarf_name (tree t, int verbosity ATTRIBUTE_UNUSED)
637 gcc_assert (DECL_P (t));
639 return (const char *) IDENTIFIER_POINTER (DECL_NAME (t));
642 /* Expands GNAT-specific GCC tree nodes. The only ones we support
643 here are and NULL_EXPR. */
646 gnat_expand_expr (tree exp, rtx target, enum machine_mode tmode,
647 int modifier, rtx *alt_rtl)
649 tree type = TREE_TYPE (exp);
652 /* Update EXP to be the new expression to expand. */
653 switch (TREE_CODE (exp))
658 allocate_dynamic_stack_space
659 (expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, TYPE_MODE (sizetype),
661 NULL_RTX, tree_low_cst (TREE_OPERAND (exp, 1), 1));
664 case UNCONSTRAINED_ARRAY_REF:
665 /* If we are evaluating just for side-effects, just evaluate our
666 operand. Otherwise, abort since this code should never appear
667 in a tree to be evaluated (objects aren't unconstrained). */
668 if (target == const0_rtx || TREE_CODE (type) == VOID_TYPE)
669 return expand_expr (TREE_OPERAND (exp, 0), const0_rtx,
672 /* ... fall through ... */
678 return expand_expr_real (new, target, tmode, modifier, alt_rtl);
681 /* Generate the RTL for the body of GNU_DECL. */
684 gnat_expand_body (tree gnu_decl)
686 tree_rest_of_compilation (gnu_decl);
689 /* Adjusts the RLI used to layout a record after all the fields have been
690 added. We only handle the packed case and cause it to use the alignment
691 that will pad the record at the end. */
694 gnat_adjust_rli (record_layout_info rli ATTRIBUTE_UNUSED)
697 /* ??? This code seems to have no actual effect; record_align should already
698 reflect the largest alignment desired by a field. jason 2003-04-01 */
699 unsigned int record_align = rli->unpadded_align;
702 /* If an alignment has been specified, don't use anything larger unless we
704 if (TYPE_ALIGN (rli->t) != 0 && TYPE_ALIGN (rli->t) < record_align)
705 record_align = MAX (rli->record_align, TYPE_ALIGN (rli->t));
707 /* If any fields have variable size, we need to force the record to be at
708 least as aligned as the alignment of that type. */
709 for (field = TYPE_FIELDS (rli->t); field; field = TREE_CHAIN (field))
710 if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST)
711 record_align = MAX (record_align, DECL_ALIGN (field));
713 if (TYPE_PACKED (rli->t))
714 rli->record_align = record_align;
718 /* These routines are used in conjunction with GCC exception handling. */
720 /* Map compile-time to run-time tree for GCC exception handling scheme. */
723 gnat_eh_runtime_type (tree type)
728 /* Return true if type A catches type B. Callback for flow analysis from
729 the exception handling part of the back-end. */
732 gnat_eh_type_covers (tree a, tree b)
734 /* a catches b if they represent the same exception id or if a
737 ??? integer_zero_node for "others" is hardwired in too many places
739 return (a == b || a == integer_zero_node);
742 /* Get the alias set corresponding to a type or expression. */
744 static alias_set_type
745 gnat_get_alias_set (tree type)
747 /* If this is a padding type, use the type of the first field. */
748 if (TREE_CODE (type) == RECORD_TYPE
749 && TYPE_IS_PADDING_P (type))
750 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
752 /* If the type is an unconstrained array, use the type of the
753 self-referential array we make. */
754 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
756 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
758 /* If the type can alias any other types, return the alias set 0. */
759 else if (TYPE_P (type)
760 && TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (type)))
766 /* GNU_TYPE is a type. Return its maximum size in bytes, if known,
767 as a constant when possible. */
770 gnat_type_max_size (tree gnu_type)
772 /* First see what we can get from TYPE_SIZE_UNIT, which might not
773 be constant even for simple expressions if it has already been
774 elaborated and possibly replaced by a VAR_DECL. */
775 tree max_unitsize = max_size (TYPE_SIZE_UNIT (gnu_type), true);
777 /* If we don't have a constant, see what we can get from TYPE_ADA_SIZE,
778 which should stay untouched. */
779 if (!host_integerp (max_unitsize, 1)
780 && (TREE_CODE (gnu_type) == RECORD_TYPE
781 || TREE_CODE (gnu_type) == UNION_TYPE
782 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
783 && TYPE_ADA_SIZE (gnu_type))
785 tree max_adasize = max_size (TYPE_ADA_SIZE (gnu_type), true);
787 /* If we have succeeded in finding a constant, round it up to the
788 type's alignment and return the result in units. */
789 if (host_integerp (max_adasize, 1))
791 = size_binop (CEIL_DIV_EXPR,
792 round_up (max_adasize, TYPE_ALIGN (gnu_type)),
799 /* GNU_TYPE is a type. Determine if it should be passed by reference by
803 default_pass_by_ref (tree gnu_type)
805 /* We pass aggregates by reference if they are sufficiently large. The
806 choice of constant here is somewhat arbitrary. We also pass by
807 reference if the target machine would either pass or return by
808 reference. Strictly speaking, we need only check the return if this
809 is an In Out parameter, but it's probably best to err on the side of
810 passing more things by reference. */
812 if (pass_by_reference (NULL, TYPE_MODE (gnu_type), gnu_type, 1))
815 if (targetm.calls.return_in_memory (gnu_type, NULL_TREE))
818 if (AGGREGATE_TYPE_P (gnu_type)
819 && (!host_integerp (TYPE_SIZE (gnu_type), 1)
820 || 0 < compare_tree_int (TYPE_SIZE (gnu_type),
821 8 * TYPE_ALIGN (gnu_type))))
827 /* GNU_TYPE is the type of a subprogram parameter. Determine from the type if
828 it should be passed by reference. */
831 must_pass_by_ref (tree gnu_type)
833 /* We pass only unconstrained objects, those required by the language
834 to be passed by reference, and objects of variable size. The latter
835 is more efficient, avoids problems with variable size temporaries,
836 and does not produce compatibility problems with C, since C does
837 not have such objects. */
838 return (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
839 || (AGGREGATE_TYPE_P (gnu_type) && TYPE_BY_REFERENCE_P (gnu_type))
840 || (TYPE_SIZE (gnu_type)
841 && TREE_CODE (TYPE_SIZE (gnu_type)) != INTEGER_CST));
844 /* This function is called by the front end to enumerate all the supported
845 modes for the machine. We pass a function which is called back with
846 the following integer parameters:
848 FLOAT_P nonzero if this represents a floating-point mode
849 COMPLEX_P nonzero is this represents a complex mode
850 COUNT count of number of items, nonzero for vector mode
851 PRECISION number of bits in data representation
852 MANTISSA number of bits in mantissa, if FP and known, else zero.
853 SIZE number of bits used to store data
854 ALIGN number of bits to which mode is aligned. */
857 enumerate_modes (void (*f) (int, int, int, int, int, int, unsigned int))
861 for (i = 0; i < NUM_MACHINE_MODES; i++)
869 enum machine_mode inner_mode = i;
871 switch (GET_MODE_CLASS (i))
878 case MODE_COMPLEX_INT:
880 inner_mode = GET_MODE_INNER (i);
882 case MODE_COMPLEX_FLOAT:
885 inner_mode = GET_MODE_INNER (i);
887 case MODE_VECTOR_INT:
889 inner_mode = GET_MODE_INNER (i);
891 case MODE_VECTOR_FLOAT:
894 inner_mode = GET_MODE_INNER (i);
900 /* Skip this mode if it's one the front end doesn't need to know about
901 (e.g., the CC modes) or if there is no add insn for that mode (or
902 any wider mode), meaning it is not supported by the hardware. If
903 this a complex or vector mode, we care about the inner mode. */
904 for (j = inner_mode; j != VOIDmode; j = GET_MODE_WIDER_MODE (j))
905 if (optab_handler (add_optab, j)->insn_code != CODE_FOR_nothing)
910 const struct real_format *fmt = REAL_MODE_FORMAT (inner_mode);
915 if (!skip_p && j != VOIDmode)
916 (*f) (float_p, complex_p, vector_p ? GET_MODE_NUNITS (i) : 0,
917 GET_MODE_BITSIZE (i), mantissa,
918 GET_MODE_SIZE (i) * BITS_PER_UNIT, GET_MODE_ALIGNMENT (i));
923 fp_prec_to_size (int prec)
925 enum machine_mode mode;
927 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
928 mode = GET_MODE_WIDER_MODE (mode))
929 if (GET_MODE_PRECISION (mode) == prec)
930 return GET_MODE_BITSIZE (mode);
936 fp_size_to_prec (int size)
938 enum machine_mode mode;
940 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
941 mode = GET_MODE_WIDER_MODE (mode))
942 if (GET_MODE_BITSIZE (mode) == size)
943 return GET_MODE_PRECISION (mode);