libguile/frames.h

   1 /* Copyright (C) 2001, 2009 Free Software Foundation, Inc.
   2  * *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public License
   5  * as published by the Free Software Foundation; either version 3 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301 USA
  17  */
  18
  19 #ifndef _SCM_FRAMES_H_
  20 #define _SCM_FRAMES_H_
  21
  22 #include <libguile.h>
  23 #include "programs.h"
  24
  25 \f
  26 /*
  27  * VM frames
  28  */
  29
  30 /* VM Frame Layout
  31    ---------------
  32
  33    | ...              |
  34    | Intermed. val. 0 | <- fp + bp->nargs + bp->nlocs = SCM_FRAME_UPPER_ADDRESS (fp)
  35    +==================+
  36    | Local variable 1 |
  37    | Local variable 0 | <- fp + bp->nargs
  38    | Argument 1       |
  39    | Argument 0       | <- fp
  40    | Program          | <- fp - 1
  41    +------------------+
  42    | Return address   |
  43    | MV return address|
  44    | Dynamic link     | <- fp - 4 = SCM_FRAME_DATA_ADDRESS (fp) = SCM_FRAME_LOWER_ADDRESS (fp)
  45    +==================+
  46    |                  |
  47
  48    As can be inferred from this drawing, it is assumed that
  49    `sizeof (SCM *) == sizeof (SCM)', since pointers (the `link' parts) are
  50    assumed to be as long as SCM objects.  */
  51
  52 #define SCM_FRAME_DATA_ADDRESS(fp)      (fp - 4)
  53 #define SCM_FRAME_UPPER_ADDRESS(fp)                             \
  54   (fp                                                           \
  55    + SCM_PROGRAM_DATA (SCM_FRAME_PROGRAM (fp))->nargs           \
  56    + SCM_PROGRAM_DATA (SCM_FRAME_PROGRAM (fp))->nlocs)
  57 #define SCM_FRAME_LOWER_ADDRESS(fp)     (fp - 4)
  58
  59 #define SCM_FRAME_BYTE_CAST(x)          ((scm_t_uint8 *) SCM_UNPACK (x))
  60 #define SCM_FRAME_STACK_CAST(x)         ((SCM *) SCM_UNPACK (x))
  61
  62 #define SCM_FRAME_RETURN_ADDRESS(fp)                            \
  63   (SCM_FRAME_BYTE_CAST (SCM_FRAME_DATA_ADDRESS (fp)[2]))
  64 #define SCM_FRAME_SET_RETURN_ADDRESS(fp, ra)                    \
  65   ((SCM_FRAME_DATA_ADDRESS (fp)[2])) = (SCM)(ra);
  66 #define SCM_FRAME_MV_RETURN_ADDRESS(fp)                         \
  67   (SCM_FRAME_BYTE_CAST (SCM_FRAME_DATA_ADDRESS (fp)[1]))
  68 #define SCM_FRAME_SET_MV_RETURN_ADDRESS(fp, mvra)               \
  69   ((SCM_FRAME_DATA_ADDRESS (fp)[1])) = (SCM)(mvra);
  70 #define SCM_FRAME_DYNAMIC_LINK(fp)                              \
  71   (SCM_FRAME_STACK_CAST (SCM_FRAME_DATA_ADDRESS (fp)[0]))
  72 #define SCM_FRAME_SET_DYNAMIC_LINK(fp, dl)                      \
  73   ((SCM_FRAME_DATA_ADDRESS (fp)[0])) = (SCM)(dl);
  74 #define SCM_FRAME_VARIABLE(fp,i)        fp[i]
  75 #define SCM_FRAME_PROGRAM(fp)           fp[-1]
  76
  77 \f
  78 /*
  79  * Heap frames
  80  */
  81
  82 SCM_API scm_t_bits scm_tc16_vm_frame;
  83
  84 struct scm_vm_frame
  85 {
  86   SCM stack_holder;
  87   SCM *fp;
  88   SCM *sp;
  89   scm_t_uint8 *ip;
  90   scm_t_ptrdiff offset;
  91 };
  92
  93 #define SCM_VM_FRAME_P(x)       SCM_SMOB_PREDICATE (scm_tc16_vm_frame, x)
  94 #define SCM_VM_FRAME_DATA(x)    ((struct scm_vm_frame*)SCM_SMOB_DATA (x))
  95 #define SCM_VM_FRAME_STACK_HOLDER(f)    SCM_VM_FRAME_DATA(f)->stack_holder
  96 #define SCM_VM_FRAME_FP(f)      SCM_VM_FRAME_DATA(f)->fp
  97 #define SCM_VM_FRAME_SP(f)      SCM_VM_FRAME_DATA(f)->sp
  98 #define SCM_VM_FRAME_IP(f)      SCM_VM_FRAME_DATA(f)->ip
  99 #define SCM_VM_FRAME_OFFSET(f)  SCM_VM_FRAME_DATA(f)->offset
 100 #define SCM_VALIDATE_VM_FRAME(p,x)      SCM_MAKE_VALIDATE (p, x, VM_FRAME_P)
 101
 102 SCM_API SCM scm_c_make_vm_frame (SCM stack_holder, SCM *fp, SCM *sp,
 103                                  scm_t_uint8 *ip, scm_t_ptrdiff offset);
 104 SCM_API SCM scm_vm_frame_p (SCM obj);
 105 SCM_API SCM scm_vm_frame_program (SCM frame);
 106 SCM_API SCM scm_vm_frame_arguments (SCM frame);
 107 SCM_API SCM scm_vm_frame_source (SCM frame);
 108 SCM_API SCM scm_vm_frame_local_ref (SCM frame, SCM index);
 109 SCM_API SCM scm_vm_frame_local_set_x (SCM frame, SCM index, SCM val);
 110 SCM_API SCM scm_vm_frame_return_address (SCM frame);
 111 SCM_API SCM scm_vm_frame_mv_return_address (SCM frame);
 112 SCM_API SCM scm_vm_frame_dynamic_link (SCM frame);
 113 SCM_API SCM scm_vm_frame_stack (SCM frame);
 114
 115 SCM_API SCM scm_c_vm_frame_prev (SCM frame);
 116
 117 SCM_INTERNAL void scm_bootstrap_frames (void);
 118 SCM_INTERNAL void scm_init_frames (void);
 119
 120 #endif /* _SCM_FRAMES_H_ */
 121
 122 /*
 123   Local Variables:
 124   c-file-style: "gnu"
 125   End:
 126 */