1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2009, Free Software Foundation, Inc. *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 3, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License distributed with GNAT; see file COPYING3. If not see *
19 * <http://www.gnu.org/licenses/>. *
21 * GNAT was originally developed by the GNAT team at New York University. *
22 * Extensive contributions were provided by Ada Core Technologies Inc. *
24 ****************************************************************************/
26 /* This file contains parts of the compiler that are required for interfacing
27 with GCC but otherwise do nothing and parts of Gigi that need to know
32 #include "coretypes.h"
35 #include "diagnostic.h"
46 #include "langhooks.h"
47 #include "langhooks-def.h"
50 #include "tree-inline.h"
53 #include "adadecode.h"
67 static bool gnat_init (void);
68 static unsigned int gnat_init_options (unsigned int, const char **);
69 static int gnat_handle_option (size_t, const char *, int);
70 static bool gnat_post_options (const char **);
71 static alias_set_type gnat_get_alias_set (tree);
72 static void gnat_print_decl (FILE *, tree, int);
73 static void gnat_print_type (FILE *, tree, int);
74 static const char *gnat_printable_name (tree, int);
75 static const char *gnat_dwarf_name (tree, int);
76 static tree gnat_return_tree (tree);
77 static int gnat_eh_type_covers (tree, tree);
78 static void gnat_parse_file (int);
79 static void internal_error_function (const char *, va_list *);
80 static tree gnat_type_max_size (const_tree);
81 static void gnat_get_subrange_bounds (const_tree, tree *, tree *);
83 /* Definitions for our language-specific hooks. */
85 #undef LANG_HOOKS_NAME
86 #define LANG_HOOKS_NAME "GNU Ada"
87 #undef LANG_HOOKS_IDENTIFIER_SIZE
88 #define LANG_HOOKS_IDENTIFIER_SIZE sizeof (struct tree_identifier)
89 #undef LANG_HOOKS_INIT
90 #define LANG_HOOKS_INIT gnat_init
91 #undef LANG_HOOKS_INIT_OPTIONS
92 #define LANG_HOOKS_INIT_OPTIONS gnat_init_options
93 #undef LANG_HOOKS_HANDLE_OPTION
94 #define LANG_HOOKS_HANDLE_OPTION gnat_handle_option
95 #undef LANG_HOOKS_POST_OPTIONS
96 #define LANG_HOOKS_POST_OPTIONS gnat_post_options
97 #undef LANG_HOOKS_PARSE_FILE
98 #define LANG_HOOKS_PARSE_FILE gnat_parse_file
99 #undef LANG_HOOKS_HASH_TYPES
100 #define LANG_HOOKS_HASH_TYPES false
101 #undef LANG_HOOKS_GETDECLS
102 #define LANG_HOOKS_GETDECLS lhd_return_null_tree_v
103 #undef LANG_HOOKS_PUSHDECL
104 #define LANG_HOOKS_PUSHDECL gnat_return_tree
105 #undef LANG_HOOKS_WRITE_GLOBALS
106 #define LANG_HOOKS_WRITE_GLOBALS gnat_write_global_declarations
107 #undef LANG_HOOKS_GET_ALIAS_SET
108 #define LANG_HOOKS_GET_ALIAS_SET gnat_get_alias_set
109 #undef LANG_HOOKS_PRINT_DECL
110 #define LANG_HOOKS_PRINT_DECL gnat_print_decl
111 #undef LANG_HOOKS_PRINT_TYPE
112 #define LANG_HOOKS_PRINT_TYPE gnat_print_type
113 #undef LANG_HOOKS_TYPE_MAX_SIZE
114 #define LANG_HOOKS_TYPE_MAX_SIZE gnat_type_max_size
115 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
116 #define LANG_HOOKS_DECL_PRINTABLE_NAME gnat_printable_name
117 #undef LANG_HOOKS_DWARF_NAME
118 #define LANG_HOOKS_DWARF_NAME gnat_dwarf_name
119 #undef LANG_HOOKS_GIMPLIFY_EXPR
120 #define LANG_HOOKS_GIMPLIFY_EXPR gnat_gimplify_expr
121 #undef LANG_HOOKS_TYPE_FOR_MODE
122 #define LANG_HOOKS_TYPE_FOR_MODE gnat_type_for_mode
123 #undef LANG_HOOKS_TYPE_FOR_SIZE
124 #define LANG_HOOKS_TYPE_FOR_SIZE gnat_type_for_size
125 #undef LANG_HOOKS_TYPES_COMPATIBLE_P
126 #define LANG_HOOKS_TYPES_COMPATIBLE_P gnat_types_compatible_p
127 #undef LANG_HOOKS_GET_SUBRANGE_BOUNDS
128 #define LANG_HOOKS_GET_SUBRANGE_BOUNDS gnat_get_subrange_bounds
129 #undef LANG_HOOKS_ATTRIBUTE_TABLE
130 #define LANG_HOOKS_ATTRIBUTE_TABLE gnat_internal_attribute_table
131 #undef LANG_HOOKS_BUILTIN_FUNCTION
132 #define LANG_HOOKS_BUILTIN_FUNCTION gnat_builtin_function
134 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
136 /* How much we want of our DWARF extensions. Some of our dwarf+ extensions
137 are incompatible with regular GDB versions, so we must make sure to only
138 produce them on explicit request. This is eventually reflected into the
139 use_gnu_debug_info_extensions common flag for later processing. */
140 static int gnat_dwarf_extensions = 0;
142 /* Command-line argc and argv. These variables are global
143 since they are imported in back_end.adb. */
144 unsigned int save_argc;
145 const char **save_argv;
147 /* GNAT argc and argv. */
148 extern int gnat_argc;
149 extern char **gnat_argv;
151 /* Declare functions we use as part of startup. */
152 extern void __gnat_initialize (void *);
153 extern void __gnat_install_SEH_handler (void *);
154 extern void adainit (void);
155 extern void _ada_gnat1drv (void);
157 /* The parser for the language. For us, we process the GNAT tree. */
160 gnat_parse_file (int set_yydebug ATTRIBUTE_UNUSED)
164 /* Call the target specific initializations. */
165 __gnat_initialize (NULL);
167 /* ??? Call the SEH initialization routine. This is to workaround
168 a bootstrap path problem. The call below should be removed at some
169 point and the SEH pointer passed to __gnat_initialize() above. */
170 __gnat_install_SEH_handler((void *)seh);
172 /* Call the front-end elaboration procedures. */
175 /* Call the front end. */
179 /* Decode all the language specific options that cannot be decoded by GCC.
180 The option decoding phase of GCC calls this routine on the flags that
181 it cannot decode. Return the number of consecutive arguments from ARGV
182 that have been successfully decoded or 0 on failure. */
185 gnat_handle_option (size_t scode, const char *arg, int value)
187 const struct cl_option *option = &cl_options[scode];
188 enum opt_code code = (enum opt_code) scode;
191 if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE)))
193 error ("missing argument to \"-%s\"", option->opt_text);
200 q = XNEWVEC (char, sizeof("-I") + strlen (arg));
203 gnat_argv[gnat_argc] = q;
210 /* We save the value of warn_uninitialized, since if they put
211 -Wuninitialized on the command line, we need to generate a
212 warning about not using it without also specifying -O. */
213 if (warn_uninitialized != 1)
214 warn_uninitialized = (value ? 2 : 0);
217 /* These are used in the GCC Makefile. */
218 case OPT_Wmissing_prototypes:
219 case OPT_Wstrict_prototypes:
220 case OPT_Wwrite_strings:
222 case OPT_Wvariadic_macros:
223 case OPT_Wold_style_definition:
224 case OPT_Wmissing_format_attribute:
225 case OPT_Woverlength_strings:
228 /* This is handled by the front-end. */
233 gnat_argv[gnat_argc] = xstrdup ("-nostdlib");
237 case OPT_feliminate_unused_debug_types:
238 /* We arrange for post_option to be able to only set the corresponding
239 flag to 1 when explicitly requested by the user. We expect the
240 default flag value to be either 0 or positive, and expose a positive
241 -f as a negative value to post_option. */
242 flag_eliminate_unused_debug_types = -value;
246 gnat_argv[gnat_argc] = xstrdup ("-fRTS");
251 warning (0, "%<-gnat%> misspelled as %<-gant%>");
253 /* ... fall through ... */
256 /* Recopy the switches without the 'gnat' prefix. */
257 gnat_argv[gnat_argc] = XNEWVEC (char, strlen (arg) + 2);
258 gnat_argv[gnat_argc][0] = '-';
259 strcpy (gnat_argv[gnat_argc] + 1, arg);
264 gnat_argv[gnat_argc] = xstrdup ("-O");
266 gnat_argv[gnat_argc] = xstrdup (arg);
271 gnat_dwarf_extensions = 1;
281 /* Initialize for option processing. */
284 gnat_init_options (unsigned int argc, const char **argv)
286 /* Initialize gnat_argv with save_argv size. */
287 gnat_argv = (char **) xmalloc ((argc + 1) * sizeof (argv[0]));
288 gnat_argv[0] = xstrdup (argv[0]); /* name of the command */
294 /* Uninitialized really means uninitialized in Ada. */
295 flag_zero_initialized_in_bss = 0;
300 /* Post-switch processing. */
303 gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
305 /* Excess precision other than "fast" requires front-end
307 if (flag_excess_precision_cmdline == EXCESS_PRECISION_STANDARD
308 && TARGET_FLT_EVAL_METHOD_NON_DEFAULT)
309 sorry ("-fexcess-precision=standard for Ada");
310 flag_excess_precision_cmdline = EXCESS_PRECISION_FAST;
312 /* ??? The warning machinery is outsmarted by Ada. */
313 warn_unused_parameter = 0;
315 /* No psABI change warnings for Ada. */
318 /* Force eliminate_unused_debug_types to 0 unless an explicit positive
319 -f has been passed. This forces the default to 0 for Ada, which might
320 differ from the common default. */
321 if (flag_eliminate_unused_debug_types < 0)
322 flag_eliminate_unused_debug_types = 1;
324 flag_eliminate_unused_debug_types = 0;
326 /* Reflect the explicit request of DWARF extensions into the common
327 flag for use by later passes. */
328 if (write_symbols == DWARF2_DEBUG)
329 use_gnu_debug_info_extensions = gnat_dwarf_extensions > 0;
334 /* Here is the function to handle the compiler error processing in GCC. */
337 internal_error_function (const char *msgid, va_list *ap)
340 char *buffer, *p, *loc;
341 String_Template temp, temp_loc;
342 Fat_Pointer fp, fp_loc;
345 /* Reset the pretty-printer. */
346 pp_clear_output_area (global_dc->printer);
348 /* Format the message into the pretty-printer. */
349 tinfo.format_spec = msgid;
351 tinfo.err_no = errno;
352 pp_format_verbatim (global_dc->printer, &tinfo);
354 /* Extract a (writable) pointer to the formatted text. */
355 buffer = xstrdup (pp_formatted_text (global_dc->printer));
357 /* Go up to the first newline. */
358 for (p = buffer; *p; p++)
366 temp.High_Bound = p - buffer;
370 s = expand_location (input_location);
371 if (flag_show_column && s.column != 0)
372 asprintf (&loc, "%s:%d:%d", s.file, s.line, s.column);
374 asprintf (&loc, "%s:%d", s.file, s.line);
375 temp_loc.Low_Bound = 1;
376 temp_loc.High_Bound = strlen (loc);
377 fp_loc.Bounds = &temp_loc;
380 Current_Error_Node = error_gnat_node;
381 Compiler_Abort (fp, -1, fp_loc);
384 /* Perform all the initialization steps that are language-specific. */
389 /* Performs whatever initialization steps needed by the language-dependent
391 gnat_init_decl_processing ();
393 /* Add the input filename as the last argument. */
394 if (main_input_filename)
396 gnat_argv[gnat_argc] = xstrdup (main_input_filename);
398 gnat_argv[gnat_argc] = NULL;
401 global_dc->internal_error = &internal_error_function;
403 /* Show that REFERENCE_TYPEs are internal and should be Pmode. */
404 internal_reference_types ();
409 /* If we are using the GCC mechanism to process exception handling, we
410 have to register the personality routine for Ada and to initialize
411 various language dependent hooks. */
414 gnat_init_gcc_eh (void)
416 #ifdef DWARF2_UNWIND_INFO
417 /* lang_dependent_init already called dwarf2out_frame_init if true. */
418 int dwarf2out_frame_initialized = dwarf2out_do_frame ();
421 /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
422 though. This could for instance lead to the emission of tables with
423 references to symbols (such as the Ada eh personality routine) within
424 libraries we won't link against. */
425 if (No_Exception_Handlers_Set ())
428 /* Tell GCC we are handling cleanup actions through exception propagation.
429 This opens possibilities that we don't take advantage of yet, but is
430 nonetheless necessary to ensure that fixup code gets assigned to the
431 right exception regions. */
432 using_eh_for_cleanups ();
434 eh_personality_libfunc = init_one_libfunc (USING_SJLJ_EXCEPTIONS
435 ? "__gnat_eh_personality_sj"
436 : "__gnat_eh_personality");
437 lang_eh_type_covers = gnat_eh_type_covers;
438 lang_eh_runtime_type = gnat_return_tree;
439 default_init_unwind_resume_libfunc ();
441 /* Turn on -fexceptions and -fnon-call-exceptions. The first one triggers
442 the generation of the necessary exception runtime tables. The second one
443 is useful for two reasons: 1/ we map some asynchronous signals like SEGV
444 to exceptions, so we need to ensure that the insns which can lead to such
445 signals are correctly attached to the exception region they pertain to,
446 2/ Some calls to pure subprograms are handled as libcall blocks and then
447 marked as "cannot trap" if the flag is not set (see emit_libcall_block).
448 We should not let this be since it is possible for such calls to actually
451 flag_non_call_exceptions = 1;
454 #ifdef DWARF2_UNWIND_INFO
455 if (!dwarf2out_frame_initialized && dwarf2out_do_frame ())
456 dwarf2out_frame_init ();
460 /* Print language-specific items in declaration NODE. */
463 gnat_print_decl (FILE *file, tree node, int indent)
465 switch (TREE_CODE (node))
468 print_node (file, "corresponding var",
469 DECL_CONST_CORRESPONDING_VAR (node), indent + 4);
473 print_node (file, "original field", DECL_ORIGINAL_FIELD (node),
478 print_node (file, "renamed object", DECL_RENAMED_OBJECT (node),
487 /* Print language-specific items in type NODE. */
490 gnat_print_type (FILE *file, tree node, int indent)
492 switch (TREE_CODE (node))
495 print_node (file, "ci/co list", TYPE_CI_CO_LIST (node), indent + 4);
499 if (TYPE_MODULAR_P (node))
500 print_node_brief (file, "modulus", TYPE_MODULUS (node), indent + 4);
501 else if (TYPE_HAS_ACTUAL_BOUNDS_P (node))
502 print_node (file, "actual bounds", TYPE_ACTUAL_BOUNDS (node),
504 else if (TYPE_VAX_FLOATING_POINT_P (node))
507 print_node (file, "index type", TYPE_INDEX_TYPE (node), indent + 4);
509 /* ... fall through ... */
513 print_node_brief (file, "RM size", TYPE_RM_SIZE (node), indent + 4);
515 /* ... fall through ... */
518 print_node_brief (file, "RM min", TYPE_RM_MIN_VALUE (node), indent + 4);
519 print_node_brief (file, "RM max", TYPE_RM_MAX_VALUE (node), indent + 4);
523 print_node (file,"actual bounds", TYPE_ACTUAL_BOUNDS (node), indent + 4);
527 if (TYPE_IS_FAT_POINTER_P (node) || TYPE_CONTAINS_TEMPLATE_P (node))
528 print_node (file, "unconstrained array",
529 TYPE_UNCONSTRAINED_ARRAY (node), indent + 4);
531 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
535 case QUAL_UNION_TYPE:
536 print_node (file, "Ada size", TYPE_ADA_SIZE (node), indent + 4);
544 /* Return the name to be printed for DECL. */
547 gnat_printable_name (tree decl, int verbosity)
549 const char *coded_name = IDENTIFIER_POINTER (DECL_NAME (decl));
550 char *ada_name = (char *) ggc_alloc (strlen (coded_name) * 2 + 60);
552 __gnat_decode (coded_name, ada_name, 0);
554 if (verbosity == 2 && !DECL_IS_BUILTIN (decl))
556 Set_Identifier_Casing (ada_name, DECL_SOURCE_FILE (decl));
557 return ggc_strdup (Name_Buffer);
563 /* Return the name to be used in DWARF debug info for DECL. */
566 gnat_dwarf_name (tree decl, int verbosity ATTRIBUTE_UNUSED)
568 gcc_assert (DECL_P (decl));
569 return (const char *) IDENTIFIER_POINTER (DECL_NAME (decl));
572 /* Do nothing (return the tree node passed). */
575 gnat_return_tree (tree t)
580 /* Return true if type A catches type B. Callback for flow analysis from
581 the exception handling part of the back-end. */
584 gnat_eh_type_covers (tree a, tree b)
586 /* a catches b if they represent the same exception id or if a
589 ??? integer_zero_node for "others" is hardwired in too many places
591 return (a == b || a == integer_zero_node);
594 /* Get the alias set corresponding to a type or expression. */
596 static alias_set_type
597 gnat_get_alias_set (tree type)
599 /* If this is a padding type, use the type of the first field. */
600 if (TREE_CODE (type) == RECORD_TYPE
601 && TYPE_IS_PADDING_P (type))
602 return get_alias_set (TREE_TYPE (TYPE_FIELDS (type)));
604 /* If the type is an unconstrained array, use the type of the
605 self-referential array we make. */
606 else if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
608 get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
610 /* If the type can alias any other types, return the alias set 0. */
611 else if (TYPE_P (type)
612 && TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (type)))
618 /* GNU_TYPE is a type. Return its maximum size in bytes, if known,
619 as a constant when possible. */
622 gnat_type_max_size (const_tree gnu_type)
624 /* First see what we can get from TYPE_SIZE_UNIT, which might not
625 be constant even for simple expressions if it has already been
626 elaborated and possibly replaced by a VAR_DECL. */
627 tree max_unitsize = max_size (TYPE_SIZE_UNIT (gnu_type), true);
629 /* If we don't have a constant, see what we can get from TYPE_ADA_SIZE,
630 which should stay untouched. */
631 if (!host_integerp (max_unitsize, 1)
632 && (TREE_CODE (gnu_type) == RECORD_TYPE
633 || TREE_CODE (gnu_type) == UNION_TYPE
634 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
635 && TYPE_ADA_SIZE (gnu_type))
637 tree max_adasize = max_size (TYPE_ADA_SIZE (gnu_type), true);
639 /* If we have succeeded in finding a constant, round it up to the
640 type's alignment and return the result in units. */
641 if (host_integerp (max_adasize, 1))
643 = size_binop (CEIL_DIV_EXPR,
644 round_up (max_adasize, TYPE_ALIGN (gnu_type)),
651 /* GNU_TYPE is a subtype of an integral type. Set LOWVAL to the low bound
652 and HIGHVAL to the high bound, respectively. */
655 gnat_get_subrange_bounds (const_tree gnu_type, tree *lowval, tree *highval)
657 *lowval = TYPE_MIN_VALUE (gnu_type);
658 *highval = TYPE_MAX_VALUE (gnu_type);
661 /* GNU_TYPE is a type. Determine if it should be passed by reference by
665 default_pass_by_ref (tree gnu_type)
667 /* We pass aggregates by reference if they are sufficiently large. The
668 choice of constant here is somewhat arbitrary. We also pass by
669 reference if the target machine would either pass or return by
670 reference. Strictly speaking, we need only check the return if this
671 is an In Out parameter, but it's probably best to err on the side of
672 passing more things by reference. */
674 if (pass_by_reference (NULL, TYPE_MODE (gnu_type), gnu_type, 1))
677 if (targetm.calls.return_in_memory (gnu_type, NULL_TREE))
680 if (AGGREGATE_TYPE_P (gnu_type)
681 && (!host_integerp (TYPE_SIZE (gnu_type), 1)
682 || 0 < compare_tree_int (TYPE_SIZE (gnu_type),
683 8 * TYPE_ALIGN (gnu_type))))
689 /* GNU_TYPE is the type of a subprogram parameter. Determine from the type if
690 it should be passed by reference. */
693 must_pass_by_ref (tree gnu_type)
695 /* We pass only unconstrained objects, those required by the language
696 to be passed by reference, and objects of variable size. The latter
697 is more efficient, avoids problems with variable size temporaries,
698 and does not produce compatibility problems with C, since C does
699 not have such objects. */
700 return (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
701 || (AGGREGATE_TYPE_P (gnu_type) && TYPE_BY_REFERENCE_P (gnu_type))
702 || (TYPE_SIZE (gnu_type)
703 && TREE_CODE (TYPE_SIZE (gnu_type)) != INTEGER_CST));
706 /* This function is called by the front end to enumerate all the supported
707 modes for the machine. We pass a function which is called back with
708 the following integer parameters:
710 FLOAT_P nonzero if this represents a floating-point mode
711 COMPLEX_P nonzero is this represents a complex mode
712 COUNT count of number of items, nonzero for vector mode
713 PRECISION number of bits in data representation
714 MANTISSA number of bits in mantissa, if FP and known, else zero.
715 SIZE number of bits used to store data
716 ALIGN number of bits to which mode is aligned. */
719 enumerate_modes (void (*f) (int, int, int, int, int, int, unsigned int))
723 for (iloop = 0; iloop < NUM_MACHINE_MODES; iloop++)
725 enum machine_mode i = (enum machine_mode) iloop;
732 enum machine_mode inner_mode = i;
734 switch (GET_MODE_CLASS (i))
741 case MODE_COMPLEX_INT:
743 inner_mode = GET_MODE_INNER (i);
745 case MODE_COMPLEX_FLOAT:
748 inner_mode = GET_MODE_INNER (i);
750 case MODE_VECTOR_INT:
752 inner_mode = GET_MODE_INNER (i);
754 case MODE_VECTOR_FLOAT:
757 inner_mode = GET_MODE_INNER (i);
763 /* Skip this mode if it's one the front end doesn't need to know about
764 (e.g., the CC modes) or if there is no add insn for that mode (or
765 any wider mode), meaning it is not supported by the hardware. If
766 this a complex or vector mode, we care about the inner mode. */
767 for (j = inner_mode; j != VOIDmode; j = GET_MODE_WIDER_MODE (j))
768 if (optab_handler (add_optab, j)->insn_code != CODE_FOR_nothing)
773 const struct real_format *fmt = REAL_MODE_FORMAT (inner_mode);
778 if (!skip_p && j != VOIDmode)
779 (*f) (float_p, complex_p, vector_p ? GET_MODE_NUNITS (i) : 0,
780 GET_MODE_BITSIZE (i), mantissa,
781 GET_MODE_SIZE (i) * BITS_PER_UNIT, GET_MODE_ALIGNMENT (i));
785 /* Return the size of the FP mode with precision PREC. */
788 fp_prec_to_size (int prec)
790 enum machine_mode mode;
792 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
793 mode = GET_MODE_WIDER_MODE (mode))
794 if (GET_MODE_PRECISION (mode) == prec)
795 return GET_MODE_BITSIZE (mode);
800 /* Return the precision of the FP mode with size SIZE. */
803 fp_size_to_prec (int size)
805 enum machine_mode mode;
807 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); mode != VOIDmode;
808 mode = GET_MODE_WIDER_MODE (mode))
809 if (GET_MODE_BITSIZE (mode) == size)
810 return GET_MODE_PRECISION (mode);