src/st-types.h

   1 /*
   2  * st-types.h
   3  *
   4  * Copyright (C) 2008 Vincent Geddes
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23 */
  24
  25 #ifndef __ST_TYPES_H__
  26 #define __ST_TYPES_H__
  27
  28 #include <stdbool.h>
  29 #include <stdint.h>
  30 #include <config.h>
  31 #include <stddef.h>
  32
  33 /* Check host data model. We only support LP64 at the moment.
  34  */
  35 #if (SIZEOF_VOID_P == 4 && SIZEOF_INT == 4)
  36 #  define ST_HOST32             1
  37 #  define ST_HOST64             0
  38 #  define ST_BITS_PER_WORD     32
  39 #  define ST_BITS_PER_INTEGER  32
  40 #elif (SIZEOF_VOID_P == 8)
  41 #  define ST_HOST32            0
  42 #  define ST_HOST64            1
  43 #  define ST_BITS_PER_WORD     64
  44 #  define ST_BITS_PER_INTEGER  32
  45 #else
  46 #  error Sorry, platform not supported. Patches welcome!
  47 #endif
  48
  49 #define ST_SMALL_INTEGER_MIN  (-ST_SMALL_INTEGER_MAX - 1)
  50 #define ST_SMALL_INTEGER_MAX  536870911
  51
  52 enum {
  53     ST_SMI_TAG,
  54     ST_POINTER_TAG,
  55     ST_CHARACTER_TAG,
  56     ST_MARK_TAG,
  57 };
  58
  59 #define ST_TAG_SIZE 2
  60
  61 /* basic oop pointer:
  62  * integral type wide enough to hold a C pointer.
  63  * Can either point to a heap object or contain a smi or Character immediate.
  64  */
  65 typedef uintptr_t st_oop;
  66
  67 typedef unsigned char    st_uchar;
  68 typedef unsigned short   st_ushort;
  69 typedef unsigned long    st_ulong;
  70 typedef unsigned int     st_uint;
  71 typedef void *           st_pointer;
  72 typedef st_uint          st_unichar;
  73
  74 static inline st_oop
  75 st_tag_pointer (st_pointer p)
  76 {
  77     return ((st_oop) p) + ST_POINTER_TAG;
  78 }
  79
  80 static inline st_oop *
  81 st_detag_pointer (st_oop oop)
  82 {
  83     return (st_oop *) (oop - ST_POINTER_TAG);
  84 }
  85
  86 #endif /* __ST_TYPES_H__ */