libguile/frames.c

   1 /* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013 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 #if HAVE_CONFIG_H
  20 #  include <config.h>
  21 #endif
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include "_scm.h"
  26 #include "frames.h"
  27 #include "vm.h"
  28 #include <verify.h>
  29
  30 /* Make sure assumptions on the layout of `struct scm_vm_frame' hold.  */
  31 verify (sizeof (SCM) == sizeof (SCM *));
  32 verify (sizeof (struct scm_vm_frame) == 3 * sizeof (SCM));
  33 verify (offsetof (struct scm_vm_frame, dynamic_link) == 0);
  34
  35 \f
  36 #define RELOC(frame, val)                               \
  37   (((SCM *) (val)) + SCM_VM_FRAME_OFFSET (frame))
  38
  39 SCM
  40 scm_c_make_frame (enum scm_vm_frame_kind frame_kind, void *stack_holder,
  41                   scm_t_ptrdiff fp_offset, scm_t_ptrdiff sp_offset,
  42                   scm_t_uint32 *ip)
  43 {
  44   struct scm_frame *p = scm_gc_malloc (sizeof (struct scm_frame),
  45                                        "vmframe");
  46   p->stack_holder = stack_holder;
  47   p->fp_offset = fp_offset;
  48   p->sp_offset = sp_offset;
  49   p->ip = ip;
  50   return scm_cell (scm_tc7_frame | (frame_kind << 8), (scm_t_bits)p);
  51 }
  52
  53 void
  54 scm_i_frame_print (SCM frame, SCM port, scm_print_state *pstate)
  55 {
  56   scm_puts_unlocked ("#<frame ", port);
  57   scm_uintprint (SCM_UNPACK (frame), 16, port);
  58   scm_putc_unlocked (' ', port);
  59   scm_write (scm_frame_procedure (frame), port);
  60   /* don't write args, they can get us into trouble. */
  61   scm_puts_unlocked (">", port);
  62 }
  63
  64 SCM*
  65 scm_i_frame_stack_base (SCM frame)
  66 #define FUNC_NAME "frame-stack-base"
  67 {
  68   void *stack_holder;
  69
  70   SCM_VALIDATE_VM_FRAME (1, frame);
  71
  72   stack_holder = SCM_VM_FRAME_STACK_HOLDER (frame);
  73
  74   switch (SCM_VM_FRAME_KIND (frame))
  75     {
  76       case SCM_VM_FRAME_KIND_CONT:
  77         return ((struct scm_vm_cont *) stack_holder)->stack_base;
  78
  79       case SCM_VM_FRAME_KIND_VM:
  80         return ((struct scm_vm *) stack_holder)->stack_base;
  81
  82       default:
  83         abort ();
  84     }
  85 }
  86 #undef FUNC_NAME
  87
  88 scm_t_ptrdiff
  89 scm_i_frame_offset (SCM frame)
  90 #define FUNC_NAME "frame-offset"
  91 {
  92   void *stack_holder;
  93
  94   SCM_VALIDATE_VM_FRAME (1, frame);
  95
  96   stack_holder = SCM_VM_FRAME_STACK_HOLDER (frame);
  97
  98   switch (SCM_VM_FRAME_KIND (frame))
  99     {
 100       case SCM_VM_FRAME_KIND_CONT:
 101         return ((struct scm_vm_cont *) stack_holder)->reloc;
 102
 103       case SCM_VM_FRAME_KIND_VM:
 104         return 0;
 105
 106       default:
 107         abort ();
 108     }
 109 }
 110 #undef FUNC_NAME
 111
 112 \f
 113 /* Scheme interface */
 114
 115 SCM_DEFINE (scm_frame_p, "frame?", 1, 0, 0,
 116             (SCM obj),
 117             "")
 118 #define FUNC_NAME s_scm_frame_p
 119 {
 120   return scm_from_bool (SCM_VM_FRAME_P (obj));
 121 }
 122 #undef FUNC_NAME
 123
 124 SCM_DEFINE (scm_frame_procedure, "frame-procedure", 1, 0, 0,
 125             (SCM frame),
 126             "")
 127 #define FUNC_NAME s_scm_frame_procedure
 128 {
 129   SCM_VALIDATE_VM_FRAME (1, frame);
 130   return SCM_FRAME_PROGRAM (SCM_VM_FRAME_FP (frame));
 131 }
 132 #undef FUNC_NAME
 133
 134 SCM_DEFINE (scm_frame_arguments, "frame-arguments", 1, 0, 0,
 135             (SCM frame),
 136             "")
 137 #define FUNC_NAME s_scm_frame_arguments
 138 {
 139   static SCM var = SCM_BOOL_F;
 140
 141   SCM_VALIDATE_VM_FRAME (1, frame);
 142
 143   if (scm_is_false (var))
 144     var = scm_c_module_lookup (scm_c_resolve_module ("system vm frame"),
 145                                "frame-arguments");
 146
 147   return scm_call_1 (SCM_VARIABLE_REF (var), frame);
 148 }
 149 #undef FUNC_NAME
 150
 151 SCM_DEFINE (scm_frame_source, "frame-source", 1, 0, 0,
 152             (SCM frame),
 153             "")
 154 #define FUNC_NAME s_scm_frame_source
 155 {
 156   SCM_VALIDATE_VM_FRAME (1, frame);
 157
 158   return scm_find_source_for_addr (scm_frame_instruction_pointer (frame));
 159 }
 160 #undef FUNC_NAME
 161
 162 SCM_DEFINE (scm_frame_num_locals, "frame-num-locals", 1, 0, 0,
 163             (SCM frame),
 164             "")
 165 #define FUNC_NAME s_scm_frame_num_locals
 166 {
 167   SCM *fp, *sp;
 168
 169   SCM_VALIDATE_VM_FRAME (1, frame);
 170
 171   fp = SCM_VM_FRAME_FP (frame);
 172   sp = SCM_VM_FRAME_SP (frame);
 173
 174   return scm_from_ptrdiff_t (SCM_FRAME_NUM_LOCALS (fp, sp));
 175 }
 176 #undef FUNC_NAME
 177
 178 SCM_DEFINE (scm_frame_local_ref, "frame-local-ref", 2, 0, 0,
 179             (SCM frame, SCM index),
 180             "")
 181 #define FUNC_NAME s_scm_frame_local_ref
 182 {
 183   SCM *fp, *sp;
 184   unsigned int i;
 185
 186   SCM_VALIDATE_VM_FRAME (1, frame);
 187   SCM_VALIDATE_UINT_COPY (2, index, i);
 188
 189   fp = SCM_VM_FRAME_FP (frame);
 190   sp = SCM_VM_FRAME_SP (frame);
 191
 192   if (i < SCM_FRAME_NUM_LOCALS (fp, sp))
 193     return SCM_FRAME_LOCAL (fp, i);
 194
 195   SCM_OUT_OF_RANGE (SCM_ARG2, index);
 196 }
 197 #undef FUNC_NAME
 198
 199 /* Need same not-yet-active frame logic here as in frame-num-locals */
 200 SCM_DEFINE (scm_frame_local_set_x, "frame-local-set!", 3, 0, 0,
 201             (SCM frame, SCM index, SCM val),
 202             "")
 203 #define FUNC_NAME s_scm_frame_local_set_x
 204 {
 205   SCM *fp, *sp;
 206   unsigned int i;
 207
 208   SCM_VALIDATE_VM_FRAME (1, frame);
 209   SCM_VALIDATE_UINT_COPY (2, index, i);
 210
 211   fp = SCM_VM_FRAME_FP (frame);
 212   sp = SCM_VM_FRAME_SP (frame);
 213
 214   if (i < SCM_FRAME_NUM_LOCALS (fp, sp))
 215     {
 216       SCM_FRAME_LOCAL (fp, i) = val;
 217       return SCM_UNSPECIFIED;
 218     }
 219
 220   SCM_OUT_OF_RANGE (SCM_ARG2, index);
 221 }
 222 #undef FUNC_NAME
 223
 224 SCM_DEFINE (scm_frame_address, "frame-address", 1, 0, 0,
 225             (SCM frame),
 226             "Return the frame pointer for @var{frame}.")
 227 #define FUNC_NAME s_scm_frame_address
 228 {
 229   SCM_VALIDATE_VM_FRAME (1, frame);
 230   return scm_from_uintptr_t ((scm_t_uintptr) SCM_VM_FRAME_FP (frame));
 231 }
 232 #undef FUNC_NAME
 233
 234 SCM_DEFINE (scm_frame_stack_pointer, "frame-stack-pointer", 1, 0, 0,
 235             (SCM frame),
 236             "")
 237 #define FUNC_NAME s_scm_frame_stack_pointer
 238 {
 239   SCM_VALIDATE_VM_FRAME (1, frame);
 240
 241   return scm_from_uintptr_t ((scm_t_uintptr) SCM_VM_FRAME_SP (frame));
 242 }
 243 #undef FUNC_NAME
 244
 245 SCM_DEFINE (scm_frame_instruction_pointer, "frame-instruction-pointer", 1, 0, 0,
 246             (SCM frame),
 247             "")
 248 #define FUNC_NAME s_scm_frame_instruction_pointer
 249 {
 250   SCM_VALIDATE_VM_FRAME (1, frame);
 251
 252   return scm_from_uintptr_t ((scm_t_uintptr) SCM_VM_FRAME_IP (frame));
 253 }
 254 #undef FUNC_NAME
 255
 256 SCM_DEFINE (scm_frame_return_address, "frame-return-address", 1, 0, 0,
 257             (SCM frame),
 258             "")
 259 #define FUNC_NAME s_scm_frame_return_address
 260 {
 261   SCM_VALIDATE_VM_FRAME (1, frame);
 262   return scm_from_uintptr_t ((scm_t_uintptr) (SCM_FRAME_RETURN_ADDRESS
 263                                               (SCM_VM_FRAME_FP (frame))));
 264 }
 265 #undef FUNC_NAME
 266
 267 SCM_DEFINE (scm_frame_dynamic_link, "frame-dynamic-link", 1, 0, 0,
 268             (SCM frame),
 269             "")
 270 #define FUNC_NAME s_scm_frame_dynamic_link
 271 {
 272   SCM_VALIDATE_VM_FRAME (1, frame);
 273   /* fixme: munge fp if holder is a continuation */
 274   return scm_from_uintptr_t
 275     ((scm_t_uintptr)
 276      RELOC (frame,
 277             SCM_FRAME_DYNAMIC_LINK (SCM_VM_FRAME_FP (frame))));
 278 }
 279 #undef FUNC_NAME
 280
 281 SCM_DEFINE (scm_frame_previous, "frame-previous", 1, 0, 0,
 282             (SCM frame),
 283             "")
 284 #define FUNC_NAME s_scm_frame_previous
 285 {
 286   SCM *this_fp, *new_fp, *new_sp;
 287   SCM proc;
 288
 289   SCM_VALIDATE_VM_FRAME (1, frame);
 290
 291  again:
 292   this_fp = SCM_VM_FRAME_FP (frame);
 293   new_fp = SCM_FRAME_DYNAMIC_LINK (this_fp);
 294   if (new_fp)
 295     {
 296       SCM *stack_base = scm_i_frame_stack_base (frame);
 297       new_fp = RELOC (frame, new_fp);
 298       new_sp = SCM_FRAME_PREVIOUS_SP (this_fp);
 299       frame = scm_c_make_frame (SCM_VM_FRAME_KIND (frame),
 300                                 SCM_VM_FRAME_STACK_HOLDER (frame),
 301                                 new_fp - stack_base, new_sp - stack_base,
 302                                 SCM_FRAME_RETURN_ADDRESS (this_fp));
 303       proc = scm_frame_procedure (frame);
 304
 305       if (SCM_PROGRAM_P (proc) && SCM_PROGRAM_IS_BOOT (proc))
 306         goto again;
 307       else
 308         return frame;
 309     }
 310   else
 311     return SCM_BOOL_F;
 312 }
 313 #undef FUNC_NAME
 314
 315 \f
 316 void
 317 scm_init_frames (void)
 318 {
 319 #ifndef SCM_MAGIC_SNARFER
 320 #include "libguile/frames.x"
 321 #endif
 322 }
 323
 324 /*
 325   Local Variables:
 326   c-file-style: "gnu"
 327   End:
 328 */