gcc/ada/gcc-interface/targtyps.c

   1 /****************************************************************************
   2  *                                                                          *
   3  *                         GNAT COMPILER COMPONENTS                         *
   4  *                                                                          *
   5  *                            T A R G T Y P S                               *
   6  *                                                                          *
   7  *                                  Body                                    *
   8  *                                                                          *
   9  *          Copyright (C) 1992-2010, Free Software Foundation, Inc.         *
  10  *                                                                          *
  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/>.                                          *
  20  *                                                                          *
  21  * GNAT was originally developed  by the GNAT team at  New York University. *
  22  * Extensive contributions were provided by Ada Core Technologies Inc.      *
  23  *                                                                          *
  24  ****************************************************************************/
  25
  26 /* Functions for retrieving target types. See Ada package Get_Targ */
  27
  28 #include "config.h"
  29 #include "system.h"
  30 #include "coretypes.h"
  31 #include "tree.h"
  32 #include "tm.h"
  33 #include "tm_p.h"
  34
  35 #include "ada.h"
  36 #include "types.h"
  37 #include "atree.h"
  38 #include "elists.h"
  39 #include "namet.h"
  40 #include "nlists.h"
  41 #include "snames.h"
  42 #include "stringt.h"
  43 #include "uintp.h"
  44 #include "urealp.h"
  45 #include "fe.h"
  46 #include "sinfo.h"
  47 #include "einfo.h"
  48 #include "ada-tree.h"
  49 #include "gigi.h"
  50
  51 /* If we don't have a specific size for Ada's equivalent of `long', use that
  52    of C.  */
  53 #ifndef ADA_LONG_TYPE_SIZE
  54 #define ADA_LONG_TYPE_SIZE LONG_TYPE_SIZE
  55 #endif
  56
  57 #ifndef WIDEST_HARDWARE_FP_SIZE
  58 #define WIDEST_HARDWARE_FP_SIZE LONG_DOUBLE_TYPE_SIZE
  59 #endif
  60
  61 /* The following provide a functional interface for the front end Ada code
  62    to determine the sizes that are used for various C types. */
  63
  64 Pos
  65 get_target_bits_per_unit (void)
  66 {
  67   return BITS_PER_UNIT;
  68 }
  69
  70 Pos
  71 get_target_bits_per_word (void)
  72 {
  73   return BITS_PER_WORD;
  74 }
  75
  76 Pos
  77 get_target_char_size (void)
  78 {
  79   return CHAR_TYPE_SIZE;
  80 }
  81
  82 Pos
  83 get_target_wchar_t_size (void)
  84 {
  85   /* We never want wide characters less than "short" in Ada.  */
  86   return MAX (SHORT_TYPE_SIZE, WCHAR_TYPE_SIZE);
  87 }
  88
  89 Pos
  90 get_target_short_size (void)
  91 {
  92   return SHORT_TYPE_SIZE;
  93 }
  94
  95 Pos
  96 get_target_int_size (void)
  97 {
  98   return INT_TYPE_SIZE;
  99 }
 100
 101 Pos
 102 get_target_long_size (void)
 103 {
 104   return ADA_LONG_TYPE_SIZE;
 105 }
 106
 107 Pos
 108 get_target_long_long_size (void)
 109 {
 110   return LONG_LONG_TYPE_SIZE;
 111 }
 112
 113 Pos
 114 get_target_float_size (void)
 115 {
 116   return fp_prec_to_size (FLOAT_TYPE_SIZE);
 117 }
 118
 119 Pos
 120 get_target_double_size (void)
 121 {
 122   return fp_prec_to_size (DOUBLE_TYPE_SIZE);
 123 }
 124
 125 Pos
 126 get_target_long_double_size (void)
 127 {
 128   return fp_prec_to_size (WIDEST_HARDWARE_FP_SIZE);
 129 }
 130
 131 Pos
 132 get_target_pointer_size (void)
 133 {
 134   return POINTER_SIZE;
 135 }
 136
 137 /* Alignment related values, mapped to attributes for functional and
 138    documentation purposes.  */
 139
 140 /* Standard'Maximum_Default_Alignment.  Maximum alignment that the compiler
 141    might choose by default for a type or object.
 142
 143    Stricter alignment requests trigger gigi's aligning_type circuitry for
 144    stack objects or objects allocated by the default allocator.  */
 145
 146 Pos
 147 get_target_maximum_default_alignment (void)
 148 {
 149   return BIGGEST_ALIGNMENT / BITS_PER_UNIT;
 150 }
 151
 152 /* Standard'Default_Allocator_Alignment.  Alignment guaranteed to be honored
 153    by the default allocator (System.Memory.Alloc or malloc if we have no
 154    run-time library at hand).
 155
 156    Stricter alignment requests trigger gigi's aligning_type circuitry for
 157    objects allocated by the default allocator.  */
 158
 159 /* ??? Need a way to get info about __gnat_malloc from here (whether it is
 160    handy and what alignment it honors).  In the meantime, resort to malloc
 161    considerations only.  */
 162
 163 /* Account for MALLOC_OBSERVABLE_ALIGNMENTs here.  Use this or the ABI
 164    guaranteed alignment if greater.  */
 165
 166 #ifdef MALLOC_OBSERVABLE_ALIGNMENT
 167 #define MALLOC_ALIGNMENT MALLOC_OBSERVABLE_ALIGNMENT
 168 #else
 169 #define MALLOC_OBSERVABLE_ALIGNMENT (2 * LONG_TYPE_SIZE)
 170 #define MALLOC_ALIGNMENT \
 171   MAX (MALLOC_ABI_ALIGNMENT, MALLOC_OBSERVABLE_ALIGNMENT)
 172 #endif
 173
 174 Pos
 175 get_target_default_allocator_alignment (void)
 176 {
 177   return MALLOC_ALIGNMENT / BITS_PER_UNIT;
 178 }
 179
 180 /* Standard'Maximum_Allowed_Alignment.  Maximum alignment that we may
 181    accept for any type or object.  */
 182
 183 #ifndef MAX_OFILE_ALIGNMENT
 184 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
 185 #endif
 186
 187 Pos
 188 get_target_maximum_allowed_alignment (void)
 189 {
 190   return MAX_OFILE_ALIGNMENT / BITS_PER_UNIT;
 191 }
 192
 193 /* Standard'Maximum_Alignment.  The single attribute initially made
 194    available, now a synonym of Standard'Maximum_Default_Alignment.  */
 195
 196 Pos
 197 get_target_maximum_alignment (void)
 198 {
 199   return get_target_maximum_default_alignment ();
 200 }
 201
 202 #ifndef FLOAT_WORDS_BIG_ENDIAN
 203 #define FLOAT_WORDS_BIG_ENDIAN WORDS_BIG_ENDIAN
 204 #endif
 205
 206 Nat
 207 get_float_words_be (void)
 208 {
 209   return FLOAT_WORDS_BIG_ENDIAN;
 210 }
 211
 212 Nat
 213 get_words_be (void)
 214 {
 215   return WORDS_BIG_ENDIAN;
 216 }
 217
 218 Nat
 219 get_bytes_be (void)
 220 {
 221   return BYTES_BIG_ENDIAN;
 222 }
 223
 224 Nat
 225 get_bits_be (void)
 226 {
 227   return BITS_BIG_ENDIAN;
 228 }
 229
 230 Nat
 231 get_target_strict_alignment (void)
 232 {
 233   return STRICT_ALIGNMENT;
 234 }
 235
 236 Nat
 237 get_target_double_float_alignment (void)
 238 {
 239 #ifdef TARGET_ALIGN_NATURAL
 240   /* This macro is only defined by the rs6000 port.  */
 241   if (!TARGET_ALIGN_NATURAL
 242       && (DEFAULT_ABI == ABI_AIX || DEFAULT_ABI == ABI_DARWIN))
 243     return 32 / BITS_PER_UNIT;
 244 #endif
 245   return 0;
 246 }
 247
 248 Nat
 249 get_target_double_scalar_alignment (void)
 250 {
 251 #ifdef TARGET_ALIGN_DOUBLE
 252   /* This macro is only defined by the i386 and sh ports.  */
 253   if (!TARGET_ALIGN_DOUBLE
 254 #ifdef TARGET_64BIT
 255       && !TARGET_64BIT
 256 #endif
 257      )
 258     return 32 / BITS_PER_UNIT;
 259 #endif
 260   return 0;
 261 }