libguile/frames.h

   1 /* Copyright (C) 2001 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 #ifndef _SCM_FRAMES_H_
  43 #define _SCM_FRAMES_H_
  44
  45 #include <libguile.h>
  46 #include "programs.h"
  47
  48 \f
  49 /*
  50  * VM frames
  51  */
  52
  53 /* VM Frame Layout
  54    ---------------
  55
  56    |                  | <- fp + bp->nargs + bp->nlocs + 4
  57    +------------------+    = SCM_FRAME_UPPER_ADDRESS (fp)
  58    | Return address   |
  59    | MV return address|
  60    | Dynamic link     |
  61    | External link    | <- fp + bp->nargs + bp->nlocs
  62    | Local variable 1 |    = SCM_FRAME_DATA_ADDRESS (fp)
  63    | Local variable 0 | <- fp + bp->nargs
  64    | Argument 1       |
  65    | Argument 0       | <- fp
  66    | Program          | <- fp - 1
  67    +------------------+    = SCM_FRAME_LOWER_ADDRESS (fp)
  68    |                  |
  69
  70    As can be inferred from this drawing, it is assumed that
  71    `sizeof (SCM *) == sizeof (SCM)', since pointers (the `link' parts) are
  72    assumed to be as long as SCM objects.  */
  73
  74 #define SCM_FRAME_DATA_ADDRESS(fp)                              \
  75   (fp + SCM_PROGRAM_DATA (SCM_FRAME_PROGRAM (fp))->nargs        \
  76       + SCM_PROGRAM_DATA (SCM_FRAME_PROGRAM (fp))->nlocs)
  77 #define SCM_FRAME_UPPER_ADDRESS(fp)     (SCM_FRAME_DATA_ADDRESS (fp) + 4)
  78 #define SCM_FRAME_LOWER_ADDRESS(fp)     (fp - 1)
  79
  80 #define SCM_FRAME_BYTE_CAST(x)          ((scm_byte_t *) SCM_UNPACK (x))
  81 #define SCM_FRAME_STACK_CAST(x)         ((SCM *) SCM_UNPACK (x))
  82
  83 #define SCM_FRAME_RETURN_ADDRESS(fp)                            \
  84   (SCM_FRAME_BYTE_CAST (SCM_FRAME_DATA_ADDRESS (fp)[3]))
  85 #define SCM_FRAME_MV_RETURN_ADDRESS(fp)                         \
  86   (SCM_FRAME_BYTE_CAST (SCM_FRAME_DATA_ADDRESS (fp)[2]))
  87 #define SCM_FRAME_DYNAMIC_LINK(fp)                              \
  88   (SCM_FRAME_STACK_CAST (SCM_FRAME_DATA_ADDRESS (fp)[1]))
  89 #define SCM_FRAME_SET_DYNAMIC_LINK(fp, dl)              \
  90   ((SCM_FRAME_DATA_ADDRESS (fp)[1])) = (SCM)(dl);
  91 #define SCM_FRAME_EXTERNAL_LINK(fp)     (SCM_FRAME_DATA_ADDRESS (fp)[0])
  92 #define SCM_FRAME_VARIABLE(fp,i)        fp[i]
  93 #define SCM_FRAME_PROGRAM(fp)           fp[-1]
  94
  95 \f
  96 /*
  97  * Heap frames
  98  */
  99
 100 extern scm_t_bits scm_tc16_vm_frame;
 101
 102 struct scm_vm_frame
 103 {
 104   SCM stack_holder;
 105   SCM *fp;
 106   SCM *sp;
 107   scm_byte_t *ip;
 108   scm_t_ptrdiff offset;
 109 };
 110
 111 #define SCM_VM_FRAME_P(x)       SCM_SMOB_PREDICATE (scm_tc16_vm_frame, x)
 112 #define SCM_VM_FRAME_DATA(x)    ((struct scm_vm_frame*)SCM_SMOB_DATA (x))
 113 #define SCM_VM_FRAME_STACK_HOLDER(f)    SCM_VM_FRAME_DATA(f)->stack_holder
 114 #define SCM_VM_FRAME_FP(f)      SCM_VM_FRAME_DATA(f)->fp
 115 #define SCM_VM_FRAME_SP(f)      SCM_VM_FRAME_DATA(f)->sp
 116 #define SCM_VM_FRAME_IP(f)      SCM_VM_FRAME_DATA(f)->ip
 117 #define SCM_VM_FRAME_OFFSET(f)  SCM_VM_FRAME_DATA(f)->offset
 118 #define SCM_VALIDATE_VM_FRAME(p,x)      SCM_MAKE_VALIDATE (p, x, VM_FRAME_P)
 119
 120 /* FIXME rename scm_byte_t */
 121 extern SCM scm_c_make_vm_frame (SCM stack_holder, SCM *fp, SCM *sp,
 122                                 scm_byte_t *ip, scm_t_ptrdiff offset);
 123 extern SCM scm_vm_frame_p (SCM obj);
 124 extern SCM scm_vm_frame_program (SCM frame);
 125 extern SCM scm_vm_frame_arguments (SCM frame);
 126 extern SCM scm_vm_frame_source (SCM frame);
 127 extern SCM scm_vm_frame_local_ref (SCM frame, SCM index);
 128 extern SCM scm_vm_frame_local_set_x (SCM frame, SCM index, SCM val);
 129 extern SCM scm_vm_frame_return_address (SCM frame);
 130 extern SCM scm_vm_frame_mv_return_address (SCM frame);
 131 extern SCM scm_vm_frame_dynamic_link (SCM frame);
 132 extern SCM scm_vm_frame_external_link (SCM frame);
 133 extern SCM scm_vm_frame_stack (SCM frame);
 134
 135 extern SCM scm_c_vm_frame_prev (SCM frame);
 136
 137 extern void scm_bootstrap_frames (void);
 138 extern void scm_init_frames (void);
 139
 140 #endif /* _SCM_FRAMES_H_ */
 141
 142 /*
 143   Local Variables:
 144   c-file-style: "gnu"
 145   End:
 146 */