1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2006, 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 HOST_WIDE_INT 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_SIGNED_TYPE
161 #define LANG_HOOKS_SIGNED_TYPE gnat_signed_type
162 #undef LANG_HOOKS_UNSIGNED_TYPE
163 #define LANG_HOOKS_UNSIGNED_TYPE gnat_unsigned_type
164 #undef LANG_HOOKS_ATTRIBUTE_TABLE
165 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
166 #undef LANG_HOOKS_BUILTIN_FUNCTION
167 #define LANG_HOOKS_BUILTIN_FUNCTION gnat_builtin_function
169 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
171 /* Tables describing GCC tree codes used only by GNAT.
173 Table indexed by tree code giving a string containing a character
174 classifying the tree code. Possibilities are
175 t, d, s, c, r, <, 1 and 2. See cp-tree.def for details. */
177 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
179 const enum tree_code_class tree_code_type[] = {
182 #include "ada-tree.def"
186 /* Table indexed by tree code giving number of expression
187 operands beyond the fixed part of the node structure.
188 Not used for types or decls. */
190 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
192 const unsigned char tree_code_length[] = {
195 #include "ada-tree.def"
199 /* Names of tree components.
200 Used for printing out the tree and error messages. */
201 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
203 const char *const tree_code_name[] = {
206 #include "ada-tree.def"
210 /* Command-line argc and argv.
211 These variables are global, since they are imported and used in
214 unsigned int save_argc;
215 const char **save_argv;
217 /* gnat standard argc argv */
219 extern int gnat_argc;
220 extern char **gnat_argv;
223 /* Declare functions we use as part of startup. */
224 extern void __gnat_initialize (void *);
225 extern void __gnat_install_SEH_handler (void *);
226 extern void adainit (void);
227 extern void _ada_gnat1drv (void);
229 /* The parser for the language. For us, we process the GNAT tree. */
232 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
236 /* Call the target specific initializations. */
237 __gnat_initialize (NULL);
239 /* ??? Call the SEH initialization routine. This is to workaround
240 a bootstrap path problem. The call below should be removed at some
241 point and the SEH pointer passed to __gnat_initialize() above. */
242 __gnat_install_SEH_handler((void *)seh);
244 /* Call the front-end elaboration procedures. */
247 /* Call the front end. */
250 /* We always have a single compilation unit in Ada. */
251 cgraph_finalize_compilation_unit ();
254 /* Decode all the language specific options that cannot be decoded by GCC.
255 The option decoding phase of GCC calls this routine on the flags that
256 it cannot decode. This routine returns the number of consecutive arguments
257 from ARGV that it successfully decoded; 0 indicates failure. */
260 gnat_handle_option (size_t scode, const char *arg, int value ATTRIBUTE_UNUSED)
262 const struct cl_option *option = &cl_options[scode];
263 enum opt_code code = (enum opt_code) scode;
266 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
268 error ("missing argument to \"-%s\"", option->opt_text);
278 q = xmalloc (sizeof("-I") + strlen (arg));
281 gnat_argv[gnat_argc] = q;
285 /* All front ends are expected to accept this. */
287 /* These are used in the GCC Makefile. */
288 case OPT_Wmissing_prototypes:
289 case OPT_Wstrict_prototypes:
290 case OPT_Wwrite_strings:
292 case OPT_Wvariadic_macros:
293 case OPT_Wold_style_definition:
294 case OPT_Wmissing_format_attribute:
295 case OPT_Woverlength_strings:
298 /* This is handled by the front-end. */
303 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
308 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
313 warning (0, "%<-gnat%> misspelled as %<-gant%>");
315 /* ... fall through ... */
318 /* Recopy the switches without the 'gnat' prefix. */
319 gnat_argv[gnat_argc] = xmalloc (strlen (arg) + 2);
320 gnat_argv[gnat_argc][0] = '-';
321 strcpy (gnat_argv[gnat_argc] + 1, arg);
326 gnat_argv[gnat_argc] = xstrdup ("-O");
328 gnat_argv[gnat_argc] = xstrdup (arg);
336 /* Initialize for option processing. */
339 gnat_init_options (unsigned int argc, const char **argv)
341 /* Initialize gnat_argv with save_argv size. */
342 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
343 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
349 /* Uninitialized really means uninitialized in Ada. */
350 flag_zero_initialized_in_bss = 0;
355 /* Post-switch processing. */
358 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
360 flag_inline_trees = 1;
364 if (flag_inline_functions)
365 flag_inline_trees = 2;
367 /* The structural alias analysis machinery essentially assumes that
368 everything is addressable (modulo bit-fields) by disregarding
369 the TYPE_NONALIASED_COMPONENT and DECL_NONADDRESSABLE_P macros. */
370 flag_tree_salias = 0;
375 /* Here is the function to handle the compiler error processing in GCC. */
378 internal_error_function (const char *msgid, va_list *ap)
381 char *buffer, *p, *loc;
382 String_Template temp, temp_loc;
383 Fat_Pointer fp, fp_loc;
386 /* Reset the pretty-printer. */
387 pp_clear_output_area (global_dc->printer);
389 /* Format the message into the pretty-printer. */
390 tinfo.format_spec = msgid;
392 tinfo.err_no = errno;
393 pp_format_verbatim (global_dc->printer, &tinfo);
395 /* Extract a (writable) pointer to the formatted text. */
396 buffer = (char*) pp_formatted_text (global_dc->printer);
398 /* Go up to the first newline. */
399 for (p = buffer; *p; p++)
407 temp.High_Bound = p - buffer;
411 s = expand_location (input_location);
412 #ifdef USE_MAPPED_LOCATION
413 if (flag_show_column && s.column != 0)
414 asprintf (&loc, "%s:%d:%d", s.file, s.line, s.column);
417 asprintf (&loc, "%s:%d", s.file, s.line);
418 temp_loc.Low_Bound = 1;
419 temp_loc.High_Bound = strlen (loc);
420 fp_loc.Bounds = &temp_loc;
423 Current_Error_Node = error_gnat_node;
424 Compiler_Abort (fp, -1, fp_loc);
427 /* Perform all the initialization steps that are language-specific. */
432 /* Initialize translations and the outer statement group. */
433 gnat_init_stmt_group ();
435 /* Performs whatever initialization steps needed by the language-dependent
437 gnat_init_decl_processing ();
439 /* Add the input filename as the last argument. */
440 gnat_argv[gnat_argc] = (char *) main_input_filename;
442 gnat_argv[gnat_argc] = 0;
444 global_dc->internal_error = &internal_error_function;
446 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
447 internal_reference_types ();
449 set_lang_adjust_rli (gnat_adjust_rli);
454 /* This function is called indirectly from toplev.c to handle incomplete
455 declarations, i.e. VAR_DECL nodes whose DECL_SIZE is zero. To be precise,
456 compile_file in toplev.c makes an indirect call through the function pointer
457 incomplete_decl_finalize_hook which is initialized to this routine in
458 init_decl_processing. */
461 gnat_finish_incomplete_decl (tree dont_care ATTRIBUTE_UNUSED)
466 /* Compute the alignment of the largest mode that can be used for copying
470 gnat_compute_largest_alignment (void)
472 enum machine_mode mode;
474 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
475 mode = GET_MODE_WIDER_MODE (mode))
476 if (mov_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing)
477 largest_move_alignment = MIN (BIGGEST_ALIGNMENT,
478 MAX (largest_move_alignment,
479 GET_MODE_ALIGNMENT (mode)));
482 /* If we are using the GCC mechanism to process exception handling, we
483 have to register the personality routine for Ada and to initialize
484 various language dependent hooks. */
487 gnat_init_gcc_eh (void)
489 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
490 though. This could for instance lead to the emission of tables with
491 references to symbols (such as the Ada eh personality routine) within
492 libraries we won't link against. */
493 if (No_Exception_Handlers_Set ())
496 /* Tell GCC we are handling cleanup actions through exception propagation.
497 This opens possibilities that we don't take advantage of yet, but is
498 nonetheless necessary to ensure that fixup code gets assigned to the
499 right exception regions. */
500 using_eh_for_cleanups ();
502 eh_personality_libfunc = init_one_libfunc ("__gnat_eh_personality");
503 lang_eh_type_covers = gnat_eh_type_covers;
504 lang_eh_runtime_type = gnat_eh_runtime_type;
505 default_init_unwind_resume_libfunc ();
507 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
508 the generation of the necessary exception runtime tables. The second one
509 is useful for two reasons: 1/ we map some asynchronous signals like SEGV
510 to exceptions, so we need to ensure that the insns which can lead to such
511 signals are correctly attached to the exception region they pertain to,
512 2/ Some calls to pure subprograms are handled as libcall blocks and then
513 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
514 We should not let this be since it is possible for such calls to actually
518 flag_non_call_exceptions = 1;
521 #ifdef DWARF2_UNWIND_INFO
522 if (dwarf2out_do_frame ())
523 dwarf2out_frame_init ();
527 /* Language hooks, first one to print language-specific items in a DECL. */
530 gnat_print_decl (FILE *file, tree node, int indent)
532 switch (TREE_CODE (node))
535 print_node (file, "const_corresponding_var",
536 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
540 print_node (file, "original_field", DECL_ORIGINAL_FIELD (node),
545 print_node (file, "renamed_object", DECL_RENAMED_OBJECT (node),
555 gnat_print_type (FILE *file, tree node, int indent)
557 switch (TREE_CODE (node))
560 print_node (file, "ci_co_list", TYPE_CI_CO_LIST (node), indent + 4);
564 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
568 if (TYPE_MODULAR_P (node))
569 print_node (file, "modulus", TYPE_MODULUS (node), indent + 4);
570 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
571 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
573 else if (TYPE_VAX_FLOATING_POINT_P (node))
576 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
578 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
582 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
586 if (TYPE_IS_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
587 print_node (file, "unconstrained array",
588 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
590 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
594 case QUAL_UNION_TYPE:
595 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
604 gnat_printable_name (tree decl, int verbosity)
606 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
607 char *ada_name = (char *) ggc_alloc (strlen (coded_name) * 2 + 60);
609 __gnat_decode (coded_name, ada_name, 0);
613 Set_Identifier_Casing (ada_name, (char *) DECL_SOURCE_FILE (decl));
614 ada_name = Name_Buffer;
617 return (const char *) ada_name;
621 gnat_dwarf_name (tree t, int verbosity ATTRIBUTE_UNUSED)
623 gcc_assert (DECL_P (t));
625 return (const char *) IDENTIFIER_POINTER (DECL_NAME (t));
628 /* Expands GNAT-specific GCC tree nodes. The only ones we support
629 here are and NULL_EXPR. */
632 gnat_expand_expr (tree exp, rtx target, enum machine_mode tmode,
633 int modifier, rtx *alt_rtl)
635 tree type = TREE_TYPE (exp);
638 /* If this is a statement, call the expansion routine for statements. */
641 gnat_expand_stmt (exp);
645 /* Update EXP to be the new expression to expand. */
646 switch (TREE_CODE (exp))
651 allocate_dynamic_stack_space
652 (expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, TYPE_MODE (sizetype),
654 NULL_RTX, tree_low_cst (TREE_OPERAND (exp, 1), 1));
657 case UNCONSTRAINED_ARRAY_REF:
658 /* If we are evaluating just for side-effects, just evaluate our
659 operand. Otherwise, abort since this code should never appear
660 in a tree to be evaluated (objects aren't unconstrained). */
661 if (target == const0_rtx || TREE_CODE (type) == VOID_TYPE)
662 return expand_expr (TREE_OPERAND (exp, 0), const0_rtx,
665 /* ... fall through ... */
671 return expand_expr_real (new, target, tmode, modifier, alt_rtl);
674 /* Generate the RTL for the body of GNU_DECL. */
677 gnat_expand_body (tree gnu_decl)
679 if (!DECL_INITIAL (gnu_decl) || DECL_INITIAL (gnu_decl) == error_mark_node)
682 tree_rest_of_compilation (gnu_decl);
684 if (DECL_STATIC_CONSTRUCTOR (gnu_decl) && targetm.have_ctors_dtors)
685 targetm.asm_out.constructor (XEXP (DECL_RTL (gnu_decl), 0),
686 DEFAULT_INIT_PRIORITY);
688 if (DECL_STATIC_DESTRUCTOR (gnu_decl) && targetm.have_ctors_dtors)
689 targetm.asm_out.destructor (XEXP (DECL_RTL (gnu_decl), 0),
690 DEFAULT_INIT_PRIORITY);
693 /* Adjusts the RLI used to layout a record after all the fields have been
694 added. We only handle the packed case and cause it to use the alignment
695 that will pad the record at the end. */
698 gnat_adjust_rli (record_layout_info rli ATTRIBUTE_UNUSED)
701 /* ??? This code seems to have no actual effect; record_align should already
702 reflect the largest alignment desired by a field. jason 2003-04-01 */
703 unsigned int record_align = rli->unpadded_align;
706 /* If an alignment has been specified, don't use anything larger unless we
708 if (TYPE_ALIGN (rli->t) != 0 && TYPE_ALIGN (rli->t) < record_align)
709 record_align = MAX (rli->record_align, TYPE_ALIGN (rli->t));
711 /* If any fields have variable size, we need to force the record to be at
712 least as aligned as the alignment of that type. */
713 for (field = TYPE_FIELDS (rli->t); field; field = TREE_CHAIN (field))
714 if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST)
715 record_align = MAX (record_align, DECL_ALIGN (field));
717 if (TYPE_PACKED (rli->t))
718 rli->record_align = record_align;
722 /* These routines are used in conjunction with GCC exception handling. */
724 /* Map compile-time to run-time tree for GCC exception handling scheme. */
727 gnat_eh_runtime_type (tree type)
732 /* Return true if type A catches type B. Callback for flow analysis from
733 the exception handling part of the back-end. */
736 gnat_eh_type_covers (tree a, tree b)
738 /* a catches b if they represent the same exception id or if a
741 ??? integer_zero_node for "others" is hardwired in too many places
743 return (a == b || a == integer_zero_node);
746 /* Get the alias set corresponding to a type or expression. */
749 gnat_get_alias_set (tree type)
751 /* If this is a padding type, use the type of the first field. */
752 if (TREE_CODE (type) == RECORD_TYPE
753 && TYPE_IS_PADDING_P (type))
754 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
756 /* If the type is an unconstrained array, use the type of the
757 self-referential array we make. */
758 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
760 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (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 (add_optab->handlers[j].insn_code != CODE_FOR_nothing)
910 const struct real_format *fmt = REAL_MODE_FORMAT (inner_mode);
912 mantissa = fmt->p * fmt->log2_b;
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);