| 1 | /* Target-dependent code for the NEC V850 for GDB, the GNU debugger. |
| 2 | Copyright 1996, Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "frame.h" |
| 22 | #include "inferior.h" |
| 23 | #include "obstack.h" |
| 24 | #include "target.h" |
| 25 | #include "value.h" |
| 26 | #include "bfd.h" |
| 27 | #include "gdb_string.h" |
| 28 | #include "gdbcore.h" |
| 29 | #include "symfile.h" |
| 30 | |
| 31 | niy(char *f, int l) |
| 32 | { |
| 33 | fprintf(stderr, "%s(%d): Not implemented yet\n", f, l); |
| 34 | } |
| 35 | #define NIY() niy(__FILE__, __LINE__) |
| 36 | |
| 37 | void |
| 38 | fr30_pop_frame() |
| 39 | { |
| 40 | NIY(); |
| 41 | } |
| 42 | |
| 43 | CORE_ADDR |
| 44 | fr30_frame_chain(struct frame_info *fi) |
| 45 | { |
| 46 | NIY(); |
| 47 | } |
| 48 | |
| 49 | CORE_ADDR |
| 50 | fr30_frame_saved_pc(struct frame_info *fi) |
| 51 | { |
| 52 | NIY(); |
| 53 | } |
| 54 | |
| 55 | CORE_ADDR |
| 56 | fr30_skip_prologue(CORE_ADDR pc) |
| 57 | { |
| 58 | NIY(); |
| 59 | } |
| 60 | |
| 61 | |
| 62 | CORE_ADDR |
| 63 | fr30_push_arguments(nargs, args, sp, struct_return, struct_addr) |
| 64 | int nargs; |
| 65 | value_ptr * args; |
| 66 | CORE_ADDR sp; |
| 67 | int struct_return; |
| 68 | CORE_ADDR struct_addr; |
| 69 | { |
| 70 | int argreg; |
| 71 | int argnum; |
| 72 | int stack_offset; |
| 73 | struct stack_arg { |
| 74 | char *val; |
| 75 | int len; |
| 76 | int offset; |
| 77 | }; |
| 78 | struct stack_arg *stack_args = |
| 79 | (struct stack_arg*)alloca (nargs * sizeof (struct stack_arg)); |
| 80 | int nstack_args = 0; |
| 81 | |
| 82 | |
| 83 | /* Initialize the integer and float register pointers. */ |
| 84 | argreg = FIRST_ARGREG; |
| 85 | |
| 86 | /* the struct_return pointer occupies the first parameter-passing reg */ |
| 87 | if (struct_return) |
| 88 | write_register (argreg++, struct_addr); |
| 89 | |
| 90 | #if(0) |
| 91 | /* The offset onto the stack at which we will start copying parameters |
| 92 | (after the registers are used up) begins at 16 in the old ABI. |
| 93 | This leaves room for the "home" area for register parameters. */ |
| 94 | stack_offset = REGISTER_SIZE * 4; |
| 95 | #else |
| 96 | /* XXX which ABI are we using ? Z.R. */ |
| 97 | stack_offset = 0; |
| 98 | #endif |
| 99 | |
| 100 | /* Process args from left to right. Store as many as allowed in |
| 101 | registers, save the rest to be pushed on the stack */ |
| 102 | for(argnum = 0; argnum < nargs; argnum++) |
| 103 | { |
| 104 | char * val; |
| 105 | value_ptr arg = args[argnum]; |
| 106 | struct type * arg_type = check_typedef (VALUE_TYPE (arg)); |
| 107 | struct type * target_type = TYPE_TARGET_TYPE (arg_type); |
| 108 | int len = TYPE_LENGTH (arg_type); |
| 109 | enum type_code typecode = TYPE_CODE (arg_type); |
| 110 | CORE_ADDR regval; |
| 111 | int newarg; |
| 112 | |
| 113 | val = (char *) VALUE_CONTENTS (arg); |
| 114 | |
| 115 | { |
| 116 | /* Copy the argument to general registers or the stack in |
| 117 | register-sized pieces. Large arguments are split between |
| 118 | registers and stack. */ |
| 119 | while (len > 0) |
| 120 | { |
| 121 | if (argreg <= LAST_ARGREG) |
| 122 | { |
| 123 | int partial_len = len < REGISTER_SIZE ? len : REGISTER_SIZE; |
| 124 | regval = extract_address (val, partial_len); |
| 125 | |
| 126 | /* It's a simple argument being passed in a general |
| 127 | register. */ |
| 128 | write_register (argreg, regval); |
| 129 | argreg++; |
| 130 | len -= partial_len; |
| 131 | val += partial_len; |
| 132 | } |
| 133 | else |
| 134 | { |
| 135 | /* keep for later pushing */ |
| 136 | stack_args[nstack_args].val = val; |
| 137 | stack_args[nstack_args++].len = len; |
| 138 | break; |
| 139 | } |
| 140 | } |
| 141 | } |
| 142 | } |
| 143 | /* now do the real stack pushing, process args right to left */ |
| 144 | while(nstack_args--) |
| 145 | { |
| 146 | sp -= stack_args[nstack_args].len; |
| 147 | write_memory(sp, stack_args[nstack_args].val, |
| 148 | stack_args[nstack_args].len); |
| 149 | } |
| 150 | |
| 151 | /* Return adjusted stack pointer. */ |
| 152 | return sp; |
| 153 | } |
| 154 | |
| 155 | _initialize_fr30_tdep() |
| 156 | { |
| 157 | extern int print_insn_fr30(bfd_vma, disassemble_info *); |
| 158 | |
| 159 | tm_print_insn = print_insn_fr30; |
| 160 | } |
| 161 | |
| 162 | |
| 163 | #if(0) /* Z.R. for now */ |
| 164 | /* Info gleaned from scanning a function's prologue. */ |
| 165 | |
| 166 | struct pifsr /* Info about one saved reg */ |
| 167 | { |
| 168 | int framereg; /* Frame reg (SP or FP) */ |
| 169 | int offset; /* Offset from framereg */ |
| 170 | int cur_frameoffset; /* Current frameoffset */ |
| 171 | int reg; /* Saved register number */ |
| 172 | }; |
| 173 | |
| 174 | struct prologue_info |
| 175 | { |
| 176 | int framereg; |
| 177 | int frameoffset; |
| 178 | int start_function; |
| 179 | struct pifsr *pifsrs; |
| 180 | }; |
| 181 | |
| 182 | static CORE_ADDR xfr30_scan_prologue PARAMS ((CORE_ADDR pc, |
| 183 | struct prologue_info *fs)); |
| 184 | \f |
| 185 | /* Function: scan_prologue |
| 186 | Scan the prologue of the function that contains PC, and record what |
| 187 | we find in PI. PI->fsr must be zeroed by the called. Returns the |
| 188 | pc after the prologue. Note that the addresses saved in pi->fsr |
| 189 | are actually just frame relative (negative offsets from the frame |
| 190 | pointer). This is because we don't know the actual value of the |
| 191 | frame pointer yet. In some circumstances, the frame pointer can't |
| 192 | be determined till after we have scanned the prologue. */ |
| 193 | |
| 194 | static CORE_ADDR |
| 195 | xfr30_scan_prologue (pc, pi) |
| 196 | CORE_ADDR pc; |
| 197 | struct prologue_info *pi; |
| 198 | { |
| 199 | CORE_ADDR func_addr, prologue_end, current_pc; |
| 200 | struct pifsr *pifsr, *pifsr_tmp; |
| 201 | int fp_used; |
| 202 | int ep_used; |
| 203 | int reg; |
| 204 | CORE_ADDR save_pc, save_end; |
| 205 | int regsave_func_p; |
| 206 | int current_sp_size; |
| 207 | int r12_tmp; |
| 208 | |
| 209 | /* First, figure out the bounds of the prologue so that we can limit the |
| 210 | search to something reasonable. */ |
| 211 | |
| 212 | if (find_pc_partial_function (pc, NULL, &func_addr, NULL)) |
| 213 | { |
| 214 | struct symtab_and_line sal; |
| 215 | |
| 216 | sal = find_pc_line (func_addr, 0); |
| 217 | |
| 218 | if (func_addr == entry_point_address ()) |
| 219 | pi->start_function = 1; |
| 220 | else |
| 221 | pi->start_function = 0; |
| 222 | |
| 223 | #if 0 |
| 224 | if (sal.line == 0) |
| 225 | prologue_end = pc; |
| 226 | else |
| 227 | prologue_end = sal.end; |
| 228 | #else |
| 229 | prologue_end = pc; |
| 230 | #endif |
| 231 | } |
| 232 | else |
| 233 | { /* We're in the boondocks */ |
| 234 | func_addr = pc - 100; |
| 235 | prologue_end = pc; |
| 236 | } |
| 237 | |
| 238 | prologue_end = min (prologue_end, pc); |
| 239 | |
| 240 | /* Now, search the prologue looking for instructions that setup fp, save |
| 241 | rp, adjust sp and such. We also record the frame offset of any saved |
| 242 | registers. */ |
| 243 | |
| 244 | pi->frameoffset = 0; |
| 245 | pi->framereg = SP_REGNUM; |
| 246 | fp_used = 0; |
| 247 | ep_used = 0; |
| 248 | pifsr = pi->pifsrs; |
| 249 | regsave_func_p = 0; |
| 250 | save_pc = 0; |
| 251 | save_end = 0; |
| 252 | r12_tmp = 0; |
| 253 | |
| 254 | #ifdef DEBUG |
| 255 | printf_filtered ("Current_pc = 0x%.8lx, prologue_end = 0x%.8lx\n", |
| 256 | (long)func_addr, (long)prologue_end); |
| 257 | #endif |
| 258 | |
| 259 | for (current_pc = func_addr; current_pc < prologue_end; current_pc += 2) |
| 260 | { |
| 261 | int insn; |
| 262 | |
| 263 | #ifdef DEBUG |
| 264 | printf_filtered ("0x%.8lx ", (long)current_pc); |
| 265 | (*tm_print_insn) (current_pc, &tm_print_insn_info); |
| 266 | #endif |
| 267 | |
| 268 | insn = read_memory_unsigned_integer (current_pc, 2); |
| 269 | |
| 270 | if ((insn & 0xffc0) == ((10 << 11) | 0x0780) && !regsave_func_p) |
| 271 | { /* jarl <func>,10 */ |
| 272 | long low_disp = read_memory_unsigned_integer (current_pc + 2, 2) & ~ (long) 1; |
| 273 | long disp = (((((insn & 0x3f) << 16) + low_disp) |
| 274 | & ~ (long) 1) ^ 0x00200000) - 0x00200000; |
| 275 | |
| 276 | save_pc = current_pc; |
| 277 | save_end = prologue_end; |
| 278 | regsave_func_p = 1; |
| 279 | current_pc += disp - 2; |
| 280 | prologue_end = (current_pc |
| 281 | + (2 * 3) /* moves to/from ep */ |
| 282 | + 4 /* addi <const>,sp,sp */ |
| 283 | + 2 /* jmp [r10] */ |
| 284 | + (2 * 12) /* sst.w to save r2, r20-r29, r31 */ |
| 285 | + 20); /* slop area */ |
| 286 | |
| 287 | #ifdef DEBUG |
| 288 | printf_filtered ("\tfound jarl <func>,r10, disp = %ld, low_disp = %ld, new pc = 0x%.8lx\n", |
| 289 | disp, low_disp, (long)current_pc + 2); |
| 290 | #endif |
| 291 | continue; |
| 292 | } |
| 293 | else if ((insn & 0xffe0) == 0x0060 && regsave_func_p) |
| 294 | { /* jmp after processing register save function */ |
| 295 | current_pc = save_pc + 2; |
| 296 | prologue_end = save_end; |
| 297 | regsave_func_p = 0; |
| 298 | #ifdef DEBUG |
| 299 | printf_filtered ("\tfound jmp after regsave func"); |
| 300 | #endif |
| 301 | } |
| 302 | else if ((insn & 0x07c0) == 0x0780 /* jarl or jr */ |
| 303 | || (insn & 0xffe0) == 0x0060 /* jmp */ |
| 304 | || (insn & 0x0780) == 0x0580) /* branch */ |
| 305 | { |
| 306 | #ifdef DEBUG |
| 307 | printf_filtered ("\n"); |
| 308 | #endif |
| 309 | break; /* Ran into end of prologue */ |
| 310 | } |
| 311 | |
| 312 | else if ((insn & 0xffe0) == ((SP_REGNUM << 11) | 0x0240)) /* add <imm>,sp */ |
| 313 | pi->frameoffset += ((insn & 0x1f) ^ 0x10) - 0x10; |
| 314 | else if (insn == ((SP_REGNUM << 11) | 0x0600 | SP_REGNUM)) /* addi <imm>,sp,sp */ |
| 315 | pi->frameoffset += read_memory_integer (current_pc + 2, 2); |
| 316 | else if (insn == ((FP_RAW_REGNUM << 11) | 0x0000 | SP_REGNUM)) /* mov sp,fp */ |
| 317 | { |
| 318 | fp_used = 1; |
| 319 | pi->framereg = FP_RAW_REGNUM; |
| 320 | } |
| 321 | |
| 322 | else if (insn == ((R12_REGNUM << 11) | 0x0640 | R0_REGNUM)) /* movhi hi(const),r0,r12 */ |
| 323 | r12_tmp = read_memory_integer (current_pc + 2, 2) << 16; |
| 324 | else if (insn == ((R12_REGNUM << 11) | 0x0620 | R12_REGNUM)) /* movea lo(const),r12,r12 */ |
| 325 | r12_tmp += read_memory_integer (current_pc + 2, 2); |
| 326 | else if (insn == ((SP_REGNUM << 11) | 0x01c0 | R12_REGNUM) && r12_tmp) /* add r12,sp */ |
| 327 | pi->frameoffset = r12_tmp; |
| 328 | else if (insn == ((EP_REGNUM << 11) | 0x0000 | SP_REGNUM)) /* mov sp,ep */ |
| 329 | ep_used = 1; |
| 330 | else if (insn == ((EP_REGNUM << 11) | 0x0000 | R1_REGNUM)) /* mov r1,ep */ |
| 331 | ep_used = 0; |
| 332 | else if (((insn & 0x07ff) == (0x0760 | SP_REGNUM) /* st.w <reg>,<offset>[sp] */ |
| 333 | || (fp_used |
| 334 | && (insn & 0x07ff) == (0x0760 | FP_RAW_REGNUM))) /* st.w <reg>,<offset>[fp] */ |
| 335 | && pifsr |
| 336 | && (((reg = (insn >> 11) & 0x1f) >= SAVE1_START_REGNUM && reg <= SAVE1_END_REGNUM) |
| 337 | || (reg >= SAVE2_START_REGNUM && reg <= SAVE2_END_REGNUM) |
| 338 | || (reg >= SAVE3_START_REGNUM && reg <= SAVE3_END_REGNUM))) |
| 339 | { |
| 340 | pifsr->reg = reg; |
| 341 | pifsr->offset = read_memory_integer (current_pc + 2, 2) & ~1; |
| 342 | pifsr->cur_frameoffset = pi->frameoffset; |
| 343 | #ifdef DEBUG |
| 344 | printf_filtered ("\tSaved register r%d, offset %d", reg, pifsr->offset); |
| 345 | #endif |
| 346 | pifsr++; |
| 347 | } |
| 348 | |
| 349 | else if (ep_used /* sst.w <reg>,<offset>[ep] */ |
| 350 | && ((insn & 0x0781) == 0x0501) |
| 351 | && pifsr |
| 352 | && (((reg = (insn >> 11) & 0x1f) >= SAVE1_START_REGNUM && reg <= SAVE1_END_REGNUM) |
| 353 | || (reg >= SAVE2_START_REGNUM && reg <= SAVE2_END_REGNUM) |
| 354 | || (reg >= SAVE3_START_REGNUM && reg <= SAVE3_END_REGNUM))) |
| 355 | { |
| 356 | pifsr->reg = reg; |
| 357 | pifsr->offset = (insn & 0x007e) << 1; |
| 358 | pifsr->cur_frameoffset = pi->frameoffset; |
| 359 | #ifdef DEBUG |
| 360 | printf_filtered ("\tSaved register r%d, offset %d", reg, pifsr->offset); |
| 361 | #endif |
| 362 | pifsr++; |
| 363 | } |
| 364 | |
| 365 | if ((insn & 0x0780) >= 0x0600) /* Four byte instruction? */ |
| 366 | current_pc += 2; |
| 367 | |
| 368 | #ifdef DEBUG |
| 369 | printf_filtered ("\n"); |
| 370 | #endif |
| 371 | } |
| 372 | |
| 373 | if (pifsr) |
| 374 | pifsr->framereg = 0; /* Tie off last entry */ |
| 375 | |
| 376 | /* Fix up any offsets to the final offset. If a frame pointer was created, use it |
| 377 | instead of the stack pointer. */ |
| 378 | for (pifsr_tmp = pi->pifsrs; pifsr_tmp && pifsr_tmp != pifsr; pifsr_tmp++) |
| 379 | { |
| 380 | pifsr_tmp->offset -= pi->frameoffset - pifsr_tmp->cur_frameoffset; |
| 381 | pifsr_tmp->framereg = pi->framereg; |
| 382 | |
| 383 | #ifdef DEBUG |
| 384 | printf_filtered ("Saved register r%d, offset = %d, framereg = r%d\n", |
| 385 | pifsr_tmp->reg, pifsr_tmp->offset, pifsr_tmp->framereg); |
| 386 | #endif |
| 387 | } |
| 388 | |
| 389 | #ifdef DEBUG |
| 390 | printf_filtered ("Framereg = r%d, frameoffset = %d\n", pi->framereg, pi->frameoffset); |
| 391 | #endif |
| 392 | |
| 393 | return current_pc; |
| 394 | } |
| 395 | |
| 396 | /* Function: init_extra_frame_info |
| 397 | Setup the frame's frame pointer, pc, and frame addresses for saved |
| 398 | registers. Most of the work is done in scan_prologue(). |
| 399 | |
| 400 | Note that when we are called for the last frame (currently active frame), |
| 401 | that fi->pc and fi->frame will already be setup. However, fi->frame will |
| 402 | be valid only if this routine uses FP. For previous frames, fi-frame will |
| 403 | always be correct (since that is derived from xfr30_frame_chain ()). |
| 404 | |
| 405 | We can be called with the PC in the call dummy under two circumstances. |
| 406 | First, during normal backtracing, second, while figuring out the frame |
| 407 | pointer just prior to calling the target function (see run_stack_dummy). */ |
| 408 | |
| 409 | void |
| 410 | xfr30_init_extra_frame_info (fi) |
| 411 | struct frame_info *fi; |
| 412 | { |
| 413 | struct prologue_info pi; |
| 414 | struct pifsr pifsrs[NUM_REGS + 1], *pifsr; |
| 415 | int reg; |
| 416 | |
| 417 | if (fi->next) |
| 418 | fi->pc = FRAME_SAVED_PC (fi->next); |
| 419 | |
| 420 | memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs); |
| 421 | |
| 422 | /* The call dummy doesn't save any registers on the stack, so we can return |
| 423 | now. */ |
| 424 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) |
| 425 | return; |
| 426 | |
| 427 | pi.pifsrs = pifsrs; |
| 428 | |
| 429 | xfr30_scan_prologue (fi->pc, &pi); |
| 430 | |
| 431 | if (!fi->next && pi.framereg == SP_REGNUM) |
| 432 | fi->frame = read_register (pi.framereg) - pi.frameoffset; |
| 433 | |
| 434 | for (pifsr = pifsrs; pifsr->framereg; pifsr++) |
| 435 | { |
| 436 | fi->fsr.regs[pifsr->reg] = pifsr->offset + fi->frame; |
| 437 | |
| 438 | if (pifsr->framereg == SP_REGNUM) |
| 439 | fi->fsr.regs[pifsr->reg] += pi.frameoffset; |
| 440 | } |
| 441 | } |
| 442 | |
| 443 | /* Function: frame_chain |
| 444 | Figure out the frame prior to FI. Unfortunately, this involves |
| 445 | scanning the prologue of the caller, which will also be done |
| 446 | shortly by xfr30_init_extra_frame_info. For the dummy frame, we |
| 447 | just return the stack pointer that was in use at the time the |
| 448 | function call was made. */ |
| 449 | |
| 450 | CORE_ADDR |
| 451 | xfr30_frame_chain (fi) |
| 452 | struct frame_info *fi; |
| 453 | { |
| 454 | struct prologue_info pi; |
| 455 | CORE_ADDR callers_pc, fp; |
| 456 | |
| 457 | /* First, find out who called us */ |
| 458 | callers_pc = FRAME_SAVED_PC (fi); |
| 459 | /* If caller is a call-dummy, then our FP bears no relation to his FP! */ |
| 460 | fp = xfr30_find_callers_reg (fi, FP_RAW_REGNUM); |
| 461 | if (PC_IN_CALL_DUMMY(callers_pc, fp, fp)) |
| 462 | return fp; /* caller is call-dummy: return oldest value of FP */ |
| 463 | |
| 464 | /* Caller is NOT a call-dummy, so everything else should just work. |
| 465 | Even if THIS frame is a call-dummy! */ |
| 466 | pi.pifsrs = NULL; |
| 467 | |
| 468 | xfr30_scan_prologue (callers_pc, &pi); |
| 469 | |
| 470 | if (pi.start_function) |
| 471 | return 0; /* Don't chain beyond the start function */ |
| 472 | |
| 473 | if (pi.framereg == FP_RAW_REGNUM) |
| 474 | return xfr30_find_callers_reg (fi, pi.framereg); |
| 475 | |
| 476 | return fi->frame - pi.frameoffset; |
| 477 | } |
| 478 | |
| 479 | /* Function: find_callers_reg |
| 480 | Find REGNUM on the stack. Otherwise, it's in an active register. |
| 481 | One thing we might want to do here is to check REGNUM against the |
| 482 | clobber mask, and somehow flag it as invalid if it isn't saved on |
| 483 | the stack somewhere. This would provide a graceful failure mode |
| 484 | when trying to get the value of caller-saves registers for an inner |
| 485 | frame. */ |
| 486 | |
| 487 | CORE_ADDR |
| 488 | xfr30_find_callers_reg (fi, regnum) |
| 489 | struct frame_info *fi; |
| 490 | int regnum; |
| 491 | { |
| 492 | for (; fi; fi = fi->next) |
| 493 | if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) |
| 494 | return generic_read_register_dummy (fi->pc, fi->frame, regnum); |
| 495 | else if (fi->fsr.regs[regnum] != 0) |
| 496 | return read_memory_unsigned_integer (fi->fsr.regs[regnum], |
| 497 | REGISTER_RAW_SIZE(regnum)); |
| 498 | |
| 499 | return read_register (regnum); |
| 500 | } |
| 501 | |
| 502 | /* Function: skip_prologue |
| 503 | Return the address of the first code past the prologue of the function. */ |
| 504 | |
| 505 | CORE_ADDR |
| 506 | xfr30_skip_prologue (pc) |
| 507 | CORE_ADDR pc; |
| 508 | { |
| 509 | CORE_ADDR func_addr, func_end; |
| 510 | |
| 511 | /* See what the symbol table says */ |
| 512 | |
| 513 | if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) |
| 514 | { |
| 515 | struct symtab_and_line sal; |
| 516 | |
| 517 | sal = find_pc_line (func_addr, 0); |
| 518 | |
| 519 | if (sal.line != 0 && sal.end < func_end) |
| 520 | return sal.end; |
| 521 | else |
| 522 | /* Either there's no line info, or the line after the prologue is after |
| 523 | the end of the function. In this case, there probably isn't a |
| 524 | prologue. */ |
| 525 | return pc; |
| 526 | } |
| 527 | |
| 528 | /* We can't find the start of this function, so there's nothing we can do. */ |
| 529 | return pc; |
| 530 | } |
| 531 | |
| 532 | /* Function: pop_frame |
| 533 | This routine gets called when either the user uses the `return' |
| 534 | command, or the call dummy breakpoint gets hit. */ |
| 535 | |
| 536 | void |
| 537 | xfr30_pop_frame (frame) |
| 538 | struct frame_info *frame; |
| 539 | { |
| 540 | int regnum; |
| 541 | |
| 542 | if (PC_IN_CALL_DUMMY(frame->pc, frame->frame, frame->frame)) |
| 543 | generic_pop_dummy_frame (); |
| 544 | else |
| 545 | { |
| 546 | write_register (PC_REGNUM, FRAME_SAVED_PC (frame)); |
| 547 | |
| 548 | for (regnum = 0; regnum < NUM_REGS; regnum++) |
| 549 | if (frame->fsr.regs[regnum] != 0) |
| 550 | write_register (regnum, |
| 551 | read_memory_unsigned_integer (frame->fsr.regs[regnum], |
| 552 | REGISTER_RAW_SIZE(regnum))); |
| 553 | |
| 554 | write_register (SP_REGNUM, FRAME_FP (frame)); |
| 555 | } |
| 556 | |
| 557 | flush_cached_frames (); |
| 558 | } |
| 559 | |
| 560 | /* Function: push_arguments |
| 561 | Setup arguments and RP for a call to the target. First four args |
| 562 | go in R6->R9, subsequent args go into sp + 16 -> sp + ... Structs |
| 563 | are passed by reference. 64 bit quantities (doubles and long |
| 564 | longs) may be split between the regs and the stack. When calling a |
| 565 | function that returns a struct, a pointer to the struct is passed |
| 566 | in as a secret first argument (always in R6). |
| 567 | |
| 568 | Stack space for the args has NOT been allocated: that job is up to us. |
| 569 | */ |
| 570 | |
| 571 | CORE_ADDR |
| 572 | xfr30_push_arguments (nargs, args, sp, struct_return, struct_addr) |
| 573 | int nargs; |
| 574 | value_ptr *args; |
| 575 | CORE_ADDR sp; |
| 576 | unsigned char struct_return; |
| 577 | CORE_ADDR struct_addr; |
| 578 | { |
| 579 | int argreg; |
| 580 | int argnum; |
| 581 | int len = 0; |
| 582 | int stack_offset; |
| 583 | |
| 584 | /* First, just for safety, make sure stack is aligned */ |
| 585 | sp &= ~3; |
| 586 | |
| 587 | /* Now make space on the stack for the args. */ |
| 588 | for (argnum = 0; argnum < nargs; argnum++) |
| 589 | len += ((TYPE_LENGTH(VALUE_TYPE(args[argnum])) + 3) & ~3); |
| 590 | sp -= len; /* possibly over-allocating, but it works... */ |
| 591 | /* (you might think we could allocate 16 bytes */ |
| 592 | /* less, but the ABI seems to use it all! ) */ |
| 593 | argreg = ARG0_REGNUM; |
| 594 | |
| 595 | /* the struct_return pointer occupies the first parameter-passing reg */ |
| 596 | if (struct_return) |
| 597 | write_register (argreg++, struct_addr); |
| 598 | |
| 599 | stack_offset = 16; |
| 600 | /* The offset onto the stack at which we will start copying parameters |
| 601 | (after the registers are used up) begins at 16 rather than at zero. |
| 602 | I don't really know why, that's just the way it seems to work. */ |
| 603 | |
| 604 | /* Now load as many as possible of the first arguments into |
| 605 | registers, and push the rest onto the stack. There are 16 bytes |
| 606 | in four registers available. Loop thru args from first to last. */ |
| 607 | for (argnum = 0; argnum < nargs; argnum++) |
| 608 | { |
| 609 | int len; |
| 610 | char *val; |
| 611 | char valbuf[REGISTER_RAW_SIZE(ARG0_REGNUM)]; |
| 612 | |
| 613 | if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT |
| 614 | && TYPE_LENGTH (VALUE_TYPE (*args)) > 8) |
| 615 | { |
| 616 | store_address (valbuf, 4, VALUE_ADDRESS (*args)); |
| 617 | len = 4; |
| 618 | val = valbuf; |
| 619 | } |
| 620 | else |
| 621 | { |
| 622 | len = TYPE_LENGTH (VALUE_TYPE (*args)); |
| 623 | val = (char *)VALUE_CONTENTS (*args); |
| 624 | } |
| 625 | |
| 626 | while (len > 0) |
| 627 | if (argreg <= ARGLAST_REGNUM) |
| 628 | { |
| 629 | CORE_ADDR regval; |
| 630 | |
| 631 | regval = extract_address (val, REGISTER_RAW_SIZE (argreg)); |
| 632 | write_register (argreg, regval); |
| 633 | |
| 634 | len -= REGISTER_RAW_SIZE (argreg); |
| 635 | val += REGISTER_RAW_SIZE (argreg); |
| 636 | argreg++; |
| 637 | } |
| 638 | else |
| 639 | { |
| 640 | write_memory (sp + stack_offset, val, 4); |
| 641 | |
| 642 | len -= 4; |
| 643 | val += 4; |
| 644 | stack_offset += 4; |
| 645 | } |
| 646 | args++; |
| 647 | } |
| 648 | return sp; |
| 649 | } |
| 650 | |
| 651 | /* Function: push_return_address (pc) |
| 652 | Set up the return address for the inferior function call. |
| 653 | Needed for targets where we don't actually execute a JSR/BSR instruction */ |
| 654 | |
| 655 | CORE_ADDR |
| 656 | xfr30_push_return_address (pc, sp) |
| 657 | CORE_ADDR pc; |
| 658 | CORE_ADDR sp; |
| 659 | { |
| 660 | write_register (RP_REGNUM, CALL_DUMMY_ADDRESS ()); |
| 661 | return sp; |
| 662 | } |
| 663 | |
| 664 | /* Function: frame_saved_pc |
| 665 | Find the caller of this frame. We do this by seeing if RP_REGNUM |
| 666 | is saved in the stack anywhere, otherwise we get it from the |
| 667 | registers. If the inner frame is a dummy frame, return its PC |
| 668 | instead of RP, because that's where "caller" of the dummy-frame |
| 669 | will be found. */ |
| 670 | |
| 671 | CORE_ADDR |
| 672 | xfr30_frame_saved_pc (fi) |
| 673 | struct frame_info *fi; |
| 674 | { |
| 675 | if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame)) |
| 676 | return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM); |
| 677 | else |
| 678 | return xfr30_find_callers_reg (fi, RP_REGNUM); |
| 679 | } |
| 680 | |
| 681 | void |
| 682 | get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval) |
| 683 | char *raw_buffer; |
| 684 | int *optimized; |
| 685 | CORE_ADDR *addrp; |
| 686 | struct frame_info *frame; |
| 687 | int regnum; |
| 688 | enum lval_type *lval; |
| 689 | { |
| 690 | generic_get_saved_register (raw_buffer, optimized, addrp, |
| 691 | frame, regnum, lval); |
| 692 | } |
| 693 | |
| 694 | |
| 695 | /* Function: fix_call_dummy |
| 696 | Pokes the callee function's address into the CALL_DUMMY assembly stub. |
| 697 | Assumes that the CALL_DUMMY looks like this: |
| 698 | jarl <offset24>, r31 |
| 699 | trap |
| 700 | */ |
| 701 | |
| 702 | int |
| 703 | xfr30_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p) |
| 704 | char *dummy; |
| 705 | CORE_ADDR sp; |
| 706 | CORE_ADDR fun; |
| 707 | int nargs; |
| 708 | value_ptr *args; |
| 709 | struct type *type; |
| 710 | int gcc_p; |
| 711 | { |
| 712 | long offset24; |
| 713 | |
| 714 | offset24 = (long) fun - (long) entry_point_address (); |
| 715 | offset24 &= 0x3fffff; |
| 716 | offset24 |= 0xff800000; /* jarl <offset24>, r31 */ |
| 717 | |
| 718 | store_unsigned_integer ((unsigned int *)&dummy[2], 2, offset24 & 0xffff); |
| 719 | store_unsigned_integer ((unsigned int *)&dummy[0], 2, offset24 >> 16); |
| 720 | return 0; |
| 721 | } |
| 722 | |
| 723 | #endif /* Z.R. */ |