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_FINISH_INCOMPLETE_DECL
131 #define LANG_HOOKS_FINISH_INCOMPLETE_DECL gnat_finish_incomplete_decl
132 #undef LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS
133 #define LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS true
134 #undef LANG_HOOKS_GET_ALIAS_SET
135 #define LANG_HOOKS_GET_ALIAS_SET gnat_get_alias_set
136 #undef LANG_HOOKS_EXPAND_EXPR
137 #define LANG_HOOKS_EXPAND_EXPR gnat_expand_expr
138 #undef LANG_HOOKS_MARK_ADDRESSABLE
139 #define LANG_HOOKS_MARK_ADDRESSABLE gnat_mark_addressable
140 #undef LANG_HOOKS_PRINT_DECL
141 #define LANG_HOOKS_PRINT_DECL gnat_print_decl
142 #undef LANG_HOOKS_PRINT_TYPE
143 #define LANG_HOOKS_PRINT_TYPE gnat_print_type
144 #undef LANG_HOOKS_TYPE_MAX_SIZE
145 #define LANG_HOOKS_TYPE_MAX_SIZE gnat_type_max_size
146 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
147 #define LANG_HOOKS_DECL_PRINTABLE_NAME gnat_printable_name
148 #undef LANG_HOOKS_DWARF_NAME
149 #define LANG_HOOKS_DWARF_NAME gnat_dwarf_name
150 #undef LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION
151 #define LANG_HOOKS_CALLGRAPH_EXPAND_FUNCTION gnat_expand_body
152 #undef LANG_HOOKS_GIMPLIFY_EXPR
153 #define LANG_HOOKS_GIMPLIFY_EXPR gnat_gimplify_expr
154 #undef LANG_HOOKS_TYPE_FOR_MODE
155 #define LANG_HOOKS_TYPE_FOR_MODE gnat_type_for_mode
156 #undef LANG_HOOKS_TYPE_FOR_SIZE
157 #define LANG_HOOKS_TYPE_FOR_SIZE gnat_type_for_size
158 #undef LANG_HOOKS_SIGNED_TYPE
159 #define LANG_HOOKS_SIGNED_TYPE gnat_signed_type
160 #undef LANG_HOOKS_UNSIGNED_TYPE
161 #define LANG_HOOKS_UNSIGNED_TYPE gnat_unsigned_type
162 #undef LANG_HOOKS_SIGNED_OR_UNSIGNED_TYPE
163 #define LANG_HOOKS_SIGNED_OR_UNSIGNED_TYPE gnat_signed_or_unsigned_type
164 #undef LANG_HOOKS_ATTRIBUTE_TABLE
165 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
167 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
169 /* Tables describing GCC tree codes used only by GNAT.
171 Table indexed by tree code giving a string containing a character
172 classifying the tree code. Possibilities are
173 t, d, s, c, r, <, 1 and 2. See cp-tree.def for details. */
175 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
177 const enum tree_code_class tree_code_type[] = {
180 #include "ada-tree.def"
184 /* Table indexed by tree code giving number of expression
185 operands beyond the fixed part of the node structure.
186 Not used for types or decls. */
188 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
190 const unsigned char tree_code_length[] = {
193 #include "ada-tree.def"
197 /* Names of tree components.
198 Used for printing out the tree and error messages. */
199 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
201 const char *const tree_code_name[] = {
204 #include "ada-tree.def"
208 /* Command-line argc and argv.
209 These variables are global, since they are imported and used in
212 unsigned int save_argc;
213 const char **save_argv;
215 /* gnat standard argc argv */
217 extern int gnat_argc;
218 extern char **gnat_argv;
221 /* Declare functions we use as part of startup. */
222 extern void __gnat_initialize (void *);
223 extern void __gnat_install_SEH_handler (void *);
224 extern void adainit (void);
225 extern void _ada_gnat1drv (void);
227 /* The parser for the language. For us, we process the GNAT tree. */
230 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
234 /* call the target specific initializations */
235 __gnat_initialize (NULL);
237 /* ??? call the SEH initialization routine, this is to workaround a
238 bootstrap path problem. The call below should be removed at some point and
239 the seh pointer passed to __gnat_initialize() above. */
241 __gnat_install_SEH_handler((void *)seh);
243 /* Call the front-end elaboration procedures */
246 /* Call the front end */
249 cgraph_finalize_compilation_unit ();
253 /* Decode all the language specific options that cannot be decoded by GCC.
254 The option decoding phase of GCC calls this routine on the flags that
255 it cannot decode. This routine returns the number of consecutive arguments
256 from ARGV that it successfully decoded; 0 indicates failure. */
259 gnat_handle_option (size_t scode, const char *arg, int value ATTRIBUTE_UNUSED)
261 const struct cl_option *option = &cl_options[scode];
262 enum opt_code code = (enum opt_code) scode;
265 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
267 error ("missing argument to \"-%s\"", option->opt_text);
277 q = xmalloc (sizeof("-I") + strlen (arg));
280 gnat_argv[gnat_argc] = q;
284 /* All front ends are expected to accept this. */
286 /* These are used in the GCC Makefile. */
287 case OPT_Wmissing_prototypes:
288 case OPT_Wstrict_prototypes:
289 case OPT_Wwrite_strings:
291 case OPT_Wvariadic_macros:
292 case OPT_Wold_style_definition:
293 case OPT_Wmissing_format_attribute:
294 case OPT_Woverlength_strings:
297 /* This is handled by the front-end. */
302 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
307 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
312 warning (0, "%<-gnat%> misspelled as %<-gant%>");
314 /* ... fall through ... */
317 /* Recopy the switches without the 'gnat' prefix. */
318 gnat_argv[gnat_argc] = xmalloc (strlen (arg) + 2);
319 gnat_argv[gnat_argc][0] = '-';
320 strcpy (gnat_argv[gnat_argc] + 1, arg);
325 gnat_argv[gnat_argc] = xstrdup ("-O");
327 gnat_argv[gnat_argc] = xstrdup (arg);
335 /* Initialize for option processing. */
338 gnat_init_options (unsigned int argc, const char **argv)
340 /* Initialize gnat_argv with save_argv size. */
341 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
342 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
348 /* Uninitialized really means uninitialized in Ada. */
349 flag_zero_initialized_in_bss = 0;
354 /* Post-switch processing. */
357 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
359 flag_inline_trees = 1;
363 if (flag_inline_functions)
364 flag_inline_trees = 2;
366 flag_tree_salias = 0;
371 /* Here is the function to handle the compiler error processing in GCC. */
374 internal_error_function (const char *msgid, va_list *ap)
379 String_Template temp;
382 /* Reset the pretty-printer. */
383 pp_clear_output_area (global_dc->printer);
385 /* Format the message into the pretty-printer. */
386 tinfo.format_spec = msgid;
388 tinfo.err_no = errno;
389 pp_format_verbatim (global_dc->printer, &tinfo);
391 /* Extract a (writable) pointer to the formatted text. */
392 buffer = (char*) pp_formatted_text (global_dc->printer);
394 /* Go up to the first newline. */
395 for (p = buffer; *p; p++)
403 temp.High_Bound = p - buffer;
407 Current_Error_Node = error_gnat_node;
408 Compiler_Abort (fp, -1);
411 /* Perform all the initialization steps that are language-specific. */
416 /* Initialize translations and the outer statement group. */
417 gnat_init_stmt_group ();
419 /* Performs whatever initialization steps needed by the language-dependent
421 gnat_init_decl_processing ();
423 /* Add the input filename as the last argument. */
424 gnat_argv[gnat_argc] = (char *) main_input_filename;
426 gnat_argv[gnat_argc] = 0;
428 global_dc->internal_error = &internal_error_function;
430 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
431 internal_reference_types ();
433 set_lang_adjust_rli (gnat_adjust_rli);
438 /* This function is called indirectly from toplev.c to handle incomplete
439 declarations, i.e. VAR_DECL nodes whose DECL_SIZE is zero. To be precise,
440 compile_file in toplev.c makes an indirect call through the function pointer
441 incomplete_decl_finalize_hook which is initialized to this routine in
442 init_decl_processing. */
445 gnat_finish_incomplete_decl (tree dont_care ATTRIBUTE_UNUSED)
450 /* Compute the alignment of the largest mode that can be used for copying
454 gnat_compute_largest_alignment (void)
456 enum machine_mode mode;
458 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
459 mode = GET_MODE_WIDER_MODE (mode))
460 if (mov_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing)
461 largest_move_alignment = MIN (BIGGEST_ALIGNMENT,
462 MAX (largest_move_alignment,
463 GET_MODE_ALIGNMENT (mode)));
466 /* If we are using the GCC mechanism to process exception handling, we
467 have to register the personality routine for Ada and to initialize
468 various language dependent hooks. */
471 gnat_init_gcc_eh (void)
473 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
474 though. This could for instance lead to the emission of tables with
475 references to symbols (such as the Ada eh personality routine) within
476 libraries we won't link against. */
477 if (No_Exception_Handlers_Set ())
480 /* Tell GCC we are handling cleanup actions through exception propagation.
481 This opens possibilities that we don't take advantage of yet, but is
482 nonetheless necessary to ensure that fixup code gets assigned to the
483 right exception regions. */
484 using_eh_for_cleanups ();
486 eh_personality_libfunc = init_one_libfunc ("__gnat_eh_personality");
487 lang_eh_type_covers = gnat_eh_type_covers;
488 lang_eh_runtime_type = gnat_eh_runtime_type;
489 default_init_unwind_resume_libfunc ();
491 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
492 the generation of the necessary exception runtime tables. The second one
493 is useful for two reasons: 1/ we map some asynchronous signals like SEGV
494 to exceptions, so we need to ensure that the insns which can lead to such
495 signals are correctly attached to the exception region they pertain to,
496 2/ Some calls to pure subprograms are handled as libcall blocks and then
497 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
498 We should not let this be since it is possible for such calls to actually
502 flag_non_call_exceptions = 1;
505 #ifdef DWARF2_UNWIND_INFO
506 if (dwarf2out_do_frame ())
507 dwarf2out_frame_init ();
511 /* Language hooks, first one to print language-specific items in a DECL. */
514 gnat_print_decl (FILE *file, tree node, int indent)
516 switch (TREE_CODE (node))
519 print_node (file, "const_corresponding_var",
520 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
524 print_node (file, "original_field", DECL_ORIGINAL_FIELD (node),
529 print_node (file, "renamed_object", DECL_RENAMED_OBJECT (node),
539 gnat_print_type (FILE *file, tree node, int indent)
541 switch (TREE_CODE (node))
544 print_node (file, "ci_co_list", TYPE_CI_CO_LIST (node), indent + 4);
548 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
552 if (TYPE_MODULAR_P (node))
553 print_node (file, "modulus", TYPE_MODULUS (node), indent + 4);
554 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
555 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
557 else if (TYPE_VAX_FLOATING_POINT_P (node))
560 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
562 print_node (file, "RM size", TYPE_RM_SIZE_NUM (node), indent + 4);
566 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
570 if (TYPE_IS_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
571 print_node (file, "unconstrained array",
572 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
574 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
578 case QUAL_UNION_TYPE:
579 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
588 gnat_printable_name (tree decl, int verbosity)
590 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
591 char *ada_name = (char *) ggc_alloc (strlen (coded_name) * 2 + 60);
593 __gnat_decode (coded_name, ada_name, 0);
597 Set_Identifier_Casing (ada_name, (char *) DECL_SOURCE_FILE (decl));
598 ada_name = Name_Buffer;
601 return (const char *) ada_name;
605 gnat_dwarf_name (tree t, int verbosity ATTRIBUTE_UNUSED)
607 gcc_assert (DECL_P (t));
609 return (const char *) IDENTIFIER_POINTER (DECL_NAME (t));
612 /* Expands GNAT-specific GCC tree nodes. The only ones we support
613 here are and NULL_EXPR. */
616 gnat_expand_expr (tree exp, rtx target, enum machine_mode tmode,
617 int modifier, rtx *alt_rtl)
619 tree type = TREE_TYPE (exp);
622 /* If this is a statement, call the expansion routine for statements. */
625 gnat_expand_stmt (exp);
629 /* Update EXP to be the new expression to expand. */
630 switch (TREE_CODE (exp))
635 allocate_dynamic_stack_space
636 (expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, TYPE_MODE (sizetype),
638 NULL_RTX, tree_low_cst (TREE_OPERAND (exp, 1), 1));
641 case UNCONSTRAINED_ARRAY_REF:
642 /* If we are evaluating just for side-effects, just evaluate our
643 operand. Otherwise, abort since this code should never appear
644 in a tree to be evaluated (objects aren't unconstrained). */
645 if (target == const0_rtx || TREE_CODE (type) == VOID_TYPE)
646 return expand_expr (TREE_OPERAND (exp, 0), const0_rtx,
649 /* ... fall through ... */
655 return expand_expr_real (new, target, tmode, modifier, alt_rtl);
658 /* Generate the RTL for the body of GNU_DECL. */
661 gnat_expand_body (tree gnu_decl)
663 if (!DECL_INITIAL (gnu_decl) || DECL_INITIAL (gnu_decl) == error_mark_node)
666 tree_rest_of_compilation (gnu_decl);
668 if (DECL_STATIC_CONSTRUCTOR (gnu_decl) && targetm.have_ctors_dtors)
669 targetm.asm_out.constructor (XEXP (DECL_RTL (gnu_decl), 0),
670 DEFAULT_INIT_PRIORITY);
672 if (DECL_STATIC_DESTRUCTOR (gnu_decl) && targetm.have_ctors_dtors)
673 targetm.asm_out.destructor (XEXP (DECL_RTL (gnu_decl), 0),
674 DEFAULT_INIT_PRIORITY);
677 /* Adjusts the RLI used to layout a record after all the fields have been
678 added. We only handle the packed case and cause it to use the alignment
679 that will pad the record at the end. */
682 gnat_adjust_rli (record_layout_info rli ATTRIBUTE_UNUSED)
685 /* ??? This code seems to have no actual effect; record_align should already
686 reflect the largest alignment desired by a field. jason 2003-04-01 */
687 unsigned int record_align = rli->unpadded_align;
690 /* If an alignment has been specified, don't use anything larger unless we
692 if (TYPE_ALIGN (rli->t) != 0 && TYPE_ALIGN (rli->t) < record_align)
693 record_align = MAX (rli->record_align, TYPE_ALIGN (rli->t));
695 /* If any fields have variable size, we need to force the record to be at
696 least as aligned as the alignment of that type. */
697 for (field = TYPE_FIELDS (rli->t); field; field = TREE_CHAIN (field))
698 if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST)
699 record_align = MAX (record_align, DECL_ALIGN (field));
701 if (TYPE_PACKED (rli->t))
702 rli->record_align = record_align;
706 /* These routines are used in conjunction with GCC exception handling. */
708 /* Map compile-time to run-time tree for GCC exception handling scheme. */
711 gnat_eh_runtime_type (tree type)
716 /* Return true if type A catches type B. Callback for flow analysis from
717 the exception handling part of the back-end. */
720 gnat_eh_type_covers (tree a, tree b)
722 /* a catches b if they represent the same exception id or if a
725 ??? integer_zero_node for "others" is hardwired in too many places
727 return (a == b || a == integer_zero_node);
730 /* Get the alias set corresponding to a type or expression. */
733 gnat_get_alias_set (tree type)
735 /* If this is a padding type, use the type of the first field. */
736 if (TREE_CODE (type) == RECORD_TYPE
737 && TYPE_IS_PADDING_P (type))
738 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
740 /* If the type is an unconstrained array, use the type of the
741 self-referential array we make. */
742 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
744 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
750 /* GNU_TYPE is a type. Return its maxium size in bytes, if known,
751 as a constant when possible. */
754 gnat_type_max_size (tree gnu_type)
756 /* First see what we can get from TYPE_SIZE_UNIT, which might not be
757 constant even for simple expressions if it has already been gimplified
758 and replaced by a VAR_DECL. */
760 tree max_unitsize = max_size (TYPE_SIZE_UNIT (gnu_type), true);
762 /* If we don't have a constant, see what we can get from TYPE_ADA_SIZE,
763 typically not gimplified. */
765 if (!host_integerp (max_unitsize, 1)
766 && (TREE_CODE (gnu_type) == RECORD_TYPE
767 || TREE_CODE (gnu_type) == UNION_TYPE
768 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
769 && TYPE_ADA_SIZE (gnu_type))
771 tree max_adasize = max_size (TYPE_ADA_SIZE (gnu_type), true);
773 /* If we have succeded in finding a constant, round it up to the
774 type's alignment and return the result in byte units. */
776 if (host_integerp (max_adasize, 1))
778 = size_binop (CEIL_DIV_EXPR,
779 round_up (max_adasize, TYPE_ALIGN (gnu_type)),
786 /* GNU_TYPE is a type. Determine if it should be passed by reference by
790 default_pass_by_ref (tree gnu_type)
792 /* We pass aggregates by reference if they are sufficiently large. The
793 choice of constant here is somewhat arbitrary. We also pass by
794 reference if the target machine would either pass or return by
795 reference. Strictly speaking, we need only check the return if this
796 is an In Out parameter, but it's probably best to err on the side of
797 passing more things by reference. */
799 if (pass_by_reference (NULL, TYPE_MODE (gnu_type), gnu_type, 1))
802 if (targetm.calls.return_in_memory (gnu_type, NULL_TREE))
805 if (AGGREGATE_TYPE_P (gnu_type)
806 && (!host_integerp (TYPE_SIZE (gnu_type), 1)
807 || 0 < compare_tree_int (TYPE_SIZE (gnu_type),
808 8 * TYPE_ALIGN (gnu_type))))
814 /* GNU_TYPE is the type of a subprogram parameter. Determine from the type if
815 it should be passed by reference. */
818 must_pass_by_ref (tree gnu_type)
820 /* We pass only unconstrained objects, those required by the language
821 to be passed by reference, and objects of variable size. The latter
822 is more efficient, avoids problems with variable size temporaries,
823 and does not produce compatibility problems with C, since C does
824 not have such objects. */
825 return (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
826 || (AGGREGATE_TYPE_P (gnu_type) && TYPE_BY_REFERENCE_P (gnu_type))
827 || (TYPE_SIZE (gnu_type)
828 && TREE_CODE (TYPE_SIZE (gnu_type)) != INTEGER_CST));
831 /* This function is called by the front end to enumerate all the supported
832 modes for the machine. We pass a function which is called back with
833 the following integer parameters:
835 FLOAT_P nonzero if this represents a floating-point mode
836 COMPLEX_P nonzero is this represents a complex mode
837 COUNT count of number of items, nonzero for vector mode
838 PRECISION number of bits in data representation
839 MANTISSA number of bits in mantissa, if FP and known, else zero.
840 SIZE number of bits used to store data
841 ALIGN number of bits to which mode is aligned. */
844 enumerate_modes (void (*f) (int, int, int, int, int, int, unsigned int))
848 for (i = 0; i < NUM_MACHINE_MODES; i++)
856 enum machine_mode inner_mode = i;
858 switch (GET_MODE_CLASS (i))
865 case MODE_COMPLEX_INT:
867 inner_mode = GET_MODE_INNER (i);
869 case MODE_COMPLEX_FLOAT:
872 inner_mode = GET_MODE_INNER (i);
874 case MODE_VECTOR_INT:
876 inner_mode = GET_MODE_INNER (i);
878 case MODE_VECTOR_FLOAT:
881 inner_mode = GET_MODE_INNER (i);
887 /* Skip this mode if it's one the front end doesn't need to know about
888 (e.g., the CC modes) or if there is no add insn for that mode (or
889 any wider mode), meaning it is not supported by the hardware. If
890 this a complex or vector mode, we care about the inner mode. */
891 for (j = inner_mode; j != VOIDmode; j = GET_MODE_WIDER_MODE (j))
892 if (add_optab->handlers[j].insn_code != CODE_FOR_nothing)
897 const struct real_format *fmt = REAL_MODE_FORMAT (inner_mode);
899 mantissa = fmt->p * fmt->log2_b;
902 if (!skip_p && j != VOIDmode)
903 (*f) (float_p, complex_p, vector_p ? GET_MODE_NUNITS (i) : 0,
904 GET_MODE_BITSIZE (i), mantissa,
905 GET_MODE_SIZE (i) * BITS_PER_UNIT, GET_MODE_ALIGNMENT (i));
910 fp_prec_to_size (int prec)
912 enum machine_mode mode;
914 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
915 mode = GET_MODE_WIDER_MODE (mode))
916 if (GET_MODE_PRECISION (mode) == prec)
917 return GET_MODE_BITSIZE (mode);
923 fp_size_to_prec (int size)
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_BITSIZE (mode) == size)
930 return GET_MODE_PRECISION (mode);