| 1 | /* Target-dependent code for the Sanyo Xstormy16a (LC590000) processor. |
| 2 | |
| 3 | Copyright (C) 2001-2017 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "frame.h" |
| 22 | #include "frame-base.h" |
| 23 | #include "frame-unwind.h" |
| 24 | #include "dwarf2-frame.h" |
| 25 | #include "symtab.h" |
| 26 | #include "gdbtypes.h" |
| 27 | #include "gdbcmd.h" |
| 28 | #include "gdbcore.h" |
| 29 | #include "value.h" |
| 30 | #include "dis-asm.h" |
| 31 | #include "inferior.h" |
| 32 | #include "arch-utils.h" |
| 33 | #include "floatformat.h" |
| 34 | #include "regcache.h" |
| 35 | #include "doublest.h" |
| 36 | #include "osabi.h" |
| 37 | #include "objfiles.h" |
| 38 | |
| 39 | enum gdb_regnum |
| 40 | { |
| 41 | /* Xstormy16 has 16 general purpose registers (R0-R15) plus PC. |
| 42 | Functions will return their values in register R2-R7 as they fit. |
| 43 | Otherwise a hidden pointer to an big enough area is given as argument |
| 44 | to the function in r2. Further arguments are beginning in r3 then. |
| 45 | R13 is used as frame pointer when GCC compiles w/o optimization |
| 46 | R14 is used as "PSW", displaying the CPU status. |
| 47 | R15 is used implicitely as stack pointer. */ |
| 48 | E_R0_REGNUM, |
| 49 | E_R1_REGNUM, |
| 50 | E_R2_REGNUM, E_1ST_ARG_REGNUM = E_R2_REGNUM, E_PTR_RET_REGNUM = E_R2_REGNUM, |
| 51 | E_R3_REGNUM, |
| 52 | E_R4_REGNUM, |
| 53 | E_R5_REGNUM, |
| 54 | E_R6_REGNUM, |
| 55 | E_R7_REGNUM, E_LST_ARG_REGNUM = E_R7_REGNUM, |
| 56 | E_R8_REGNUM, |
| 57 | E_R9_REGNUM, |
| 58 | E_R10_REGNUM, |
| 59 | E_R11_REGNUM, |
| 60 | E_R12_REGNUM, |
| 61 | E_R13_REGNUM, E_FP_REGNUM = E_R13_REGNUM, |
| 62 | E_R14_REGNUM, E_PSW_REGNUM = E_R14_REGNUM, |
| 63 | E_R15_REGNUM, E_SP_REGNUM = E_R15_REGNUM, |
| 64 | E_PC_REGNUM, |
| 65 | E_NUM_REGS |
| 66 | }; |
| 67 | |
| 68 | /* Use an invalid address value as 'not available' marker. */ |
| 69 | enum { REG_UNAVAIL = (CORE_ADDR) -1 }; |
| 70 | |
| 71 | struct xstormy16_frame_cache |
| 72 | { |
| 73 | /* Base address. */ |
| 74 | CORE_ADDR base; |
| 75 | CORE_ADDR pc; |
| 76 | LONGEST framesize; |
| 77 | int uses_fp; |
| 78 | CORE_ADDR saved_regs[E_NUM_REGS]; |
| 79 | CORE_ADDR saved_sp; |
| 80 | }; |
| 81 | |
| 82 | /* Size of instructions, registers, etc. */ |
| 83 | enum |
| 84 | { |
| 85 | xstormy16_inst_size = 2, |
| 86 | xstormy16_reg_size = 2, |
| 87 | xstormy16_pc_size = 4 |
| 88 | }; |
| 89 | |
| 90 | /* Size of return datatype which fits into the remaining return registers. */ |
| 91 | #define E_MAX_RETTYPE_SIZE(regnum) ((E_LST_ARG_REGNUM - (regnum) + 1) \ |
| 92 | * xstormy16_reg_size) |
| 93 | |
| 94 | /* Size of return datatype which fits into all return registers. */ |
| 95 | enum |
| 96 | { |
| 97 | E_MAX_RETTYPE_SIZE_IN_REGS = E_MAX_RETTYPE_SIZE (E_R2_REGNUM) |
| 98 | }; |
| 99 | |
| 100 | /* Function: xstormy16_register_name |
| 101 | Returns the name of the standard Xstormy16 register N. */ |
| 102 | |
| 103 | static const char * |
| 104 | xstormy16_register_name (struct gdbarch *gdbarch, int regnum) |
| 105 | { |
| 106 | static char *register_names[] = { |
| 107 | "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", |
| 108 | "r8", "r9", "r10", "r11", "r12", "r13", |
| 109 | "psw", "sp", "pc" |
| 110 | }; |
| 111 | |
| 112 | if (regnum < 0 || regnum >= E_NUM_REGS) |
| 113 | internal_error (__FILE__, __LINE__, |
| 114 | _("xstormy16_register_name: illegal register number %d"), |
| 115 | regnum); |
| 116 | else |
| 117 | return register_names[regnum]; |
| 118 | |
| 119 | } |
| 120 | |
| 121 | static struct type * |
| 122 | xstormy16_register_type (struct gdbarch *gdbarch, int regnum) |
| 123 | { |
| 124 | if (regnum == E_PC_REGNUM) |
| 125 | return builtin_type (gdbarch)->builtin_uint32; |
| 126 | else |
| 127 | return builtin_type (gdbarch)->builtin_uint16; |
| 128 | } |
| 129 | |
| 130 | /* Function: xstormy16_type_is_scalar |
| 131 | Makes the decision if a given type is a scalar types. Scalar |
| 132 | types are returned in the registers r2-r7 as they fit. */ |
| 133 | |
| 134 | static int |
| 135 | xstormy16_type_is_scalar (struct type *t) |
| 136 | { |
| 137 | return (TYPE_CODE(t) != TYPE_CODE_STRUCT |
| 138 | && TYPE_CODE(t) != TYPE_CODE_UNION |
| 139 | && TYPE_CODE(t) != TYPE_CODE_ARRAY); |
| 140 | } |
| 141 | |
| 142 | /* Function: xstormy16_use_struct_convention |
| 143 | Returns non-zero if the given struct type will be returned using |
| 144 | a special convention, rather than the normal function return method. |
| 145 | 7sed in the contexts of the "return" command, and of |
| 146 | target function calls from the debugger. */ |
| 147 | |
| 148 | static int |
| 149 | xstormy16_use_struct_convention (struct type *type) |
| 150 | { |
| 151 | return !xstormy16_type_is_scalar (type) |
| 152 | || TYPE_LENGTH (type) > E_MAX_RETTYPE_SIZE_IN_REGS; |
| 153 | } |
| 154 | |
| 155 | /* Function: xstormy16_extract_return_value |
| 156 | Find a function's return value in the appropriate registers (in |
| 157 | regbuf), and copy it into valbuf. */ |
| 158 | |
| 159 | static void |
| 160 | xstormy16_extract_return_value (struct type *type, struct regcache *regcache, |
| 161 | gdb_byte *valbuf) |
| 162 | { |
| 163 | int len = TYPE_LENGTH (type); |
| 164 | int i, regnum = E_1ST_ARG_REGNUM; |
| 165 | |
| 166 | for (i = 0; i < len; i += xstormy16_reg_size) |
| 167 | regcache_raw_read (regcache, regnum++, valbuf + i); |
| 168 | } |
| 169 | |
| 170 | /* Function: xstormy16_store_return_value |
| 171 | Copy the function return value from VALBUF into the |
| 172 | proper location for a function return. |
| 173 | Called only in the context of the "return" command. */ |
| 174 | |
| 175 | static void |
| 176 | xstormy16_store_return_value (struct type *type, struct regcache *regcache, |
| 177 | const gdb_byte *valbuf) |
| 178 | { |
| 179 | if (TYPE_LENGTH (type) == 1) |
| 180 | { |
| 181 | /* Add leading zeros to the value. */ |
| 182 | gdb_byte buf[xstormy16_reg_size]; |
| 183 | memset (buf, 0, xstormy16_reg_size); |
| 184 | memcpy (buf, valbuf, 1); |
| 185 | regcache_raw_write (regcache, E_1ST_ARG_REGNUM, buf); |
| 186 | } |
| 187 | else |
| 188 | { |
| 189 | int len = TYPE_LENGTH (type); |
| 190 | int i, regnum = E_1ST_ARG_REGNUM; |
| 191 | |
| 192 | for (i = 0; i < len; i += xstormy16_reg_size) |
| 193 | regcache_raw_write (regcache, regnum++, valbuf + i); |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | static enum return_value_convention |
| 198 | xstormy16_return_value (struct gdbarch *gdbarch, struct value *function, |
| 199 | struct type *type, struct regcache *regcache, |
| 200 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 201 | { |
| 202 | if (xstormy16_use_struct_convention (type)) |
| 203 | return RETURN_VALUE_STRUCT_CONVENTION; |
| 204 | if (writebuf) |
| 205 | xstormy16_store_return_value (type, regcache, writebuf); |
| 206 | else if (readbuf) |
| 207 | xstormy16_extract_return_value (type, regcache, readbuf); |
| 208 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 209 | } |
| 210 | |
| 211 | static CORE_ADDR |
| 212 | xstormy16_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr) |
| 213 | { |
| 214 | if (addr & 1) |
| 215 | ++addr; |
| 216 | return addr; |
| 217 | } |
| 218 | |
| 219 | /* Function: xstormy16_push_dummy_call |
| 220 | Setup the function arguments for GDB to call a function in the inferior. |
| 221 | Called only in the context of a target function call from the debugger. |
| 222 | Returns the value of the SP register after the args are pushed. */ |
| 223 | |
| 224 | static CORE_ADDR |
| 225 | xstormy16_push_dummy_call (struct gdbarch *gdbarch, |
| 226 | struct value *function, |
| 227 | struct regcache *regcache, |
| 228 | CORE_ADDR bp_addr, int nargs, |
| 229 | struct value **args, |
| 230 | CORE_ADDR sp, int struct_return, |
| 231 | CORE_ADDR struct_addr) |
| 232 | { |
| 233 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 234 | CORE_ADDR stack_dest = sp; |
| 235 | int argreg = E_1ST_ARG_REGNUM; |
| 236 | int i, j; |
| 237 | int typelen, slacklen; |
| 238 | const gdb_byte *val; |
| 239 | gdb_byte buf[xstormy16_pc_size]; |
| 240 | |
| 241 | /* If struct_return is true, then the struct return address will |
| 242 | consume one argument-passing register. */ |
| 243 | if (struct_return) |
| 244 | { |
| 245 | regcache_cooked_write_unsigned (regcache, E_PTR_RET_REGNUM, struct_addr); |
| 246 | argreg++; |
| 247 | } |
| 248 | |
| 249 | /* Arguments are passed in R2-R7 as they fit. If an argument doesn't |
| 250 | fit in the remaining registers we're switching over to the stack. |
| 251 | No argument is put on stack partially and as soon as we switched |
| 252 | over to stack no further argument is put in a register even if it |
| 253 | would fit in the remaining unused registers. */ |
| 254 | for (i = 0; i < nargs && argreg <= E_LST_ARG_REGNUM; i++) |
| 255 | { |
| 256 | typelen = TYPE_LENGTH (value_enclosing_type (args[i])); |
| 257 | if (typelen > E_MAX_RETTYPE_SIZE (argreg)) |
| 258 | break; |
| 259 | |
| 260 | /* Put argument into registers wordwise. */ |
| 261 | val = value_contents (args[i]); |
| 262 | for (j = 0; j < typelen; j += xstormy16_reg_size) |
| 263 | { |
| 264 | ULONGEST regval; |
| 265 | int size = (typelen - j == 1) ? 1 : xstormy16_reg_size; |
| 266 | |
| 267 | regval = extract_unsigned_integer (val + j, size, byte_order); |
| 268 | regcache_cooked_write_unsigned (regcache, argreg++, regval); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | /* Align SP */ |
| 273 | stack_dest = xstormy16_frame_align (gdbarch, stack_dest); |
| 274 | |
| 275 | /* Loop backwards through remaining arguments and push them on the stack, |
| 276 | wordaligned. */ |
| 277 | for (j = nargs - 1; j >= i; j--) |
| 278 | { |
| 279 | gdb_byte *val; |
| 280 | struct cleanup *back_to; |
| 281 | const gdb_byte *bytes = value_contents (args[j]); |
| 282 | |
| 283 | typelen = TYPE_LENGTH (value_enclosing_type (args[j])); |
| 284 | slacklen = typelen & 1; |
| 285 | val = (gdb_byte *) xmalloc (typelen + slacklen); |
| 286 | back_to = make_cleanup (xfree, val); |
| 287 | memcpy (val, bytes, typelen); |
| 288 | memset (val + typelen, 0, slacklen); |
| 289 | |
| 290 | /* Now write this data to the stack. The stack grows upwards. */ |
| 291 | write_memory (stack_dest, val, typelen + slacklen); |
| 292 | stack_dest += typelen + slacklen; |
| 293 | do_cleanups (back_to); |
| 294 | } |
| 295 | |
| 296 | store_unsigned_integer (buf, xstormy16_pc_size, byte_order, bp_addr); |
| 297 | write_memory (stack_dest, buf, xstormy16_pc_size); |
| 298 | stack_dest += xstormy16_pc_size; |
| 299 | |
| 300 | /* Update stack pointer. */ |
| 301 | regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, stack_dest); |
| 302 | |
| 303 | /* Return the new stack pointer minus the return address slot since |
| 304 | that's what DWARF2/GCC uses as the frame's CFA. */ |
| 305 | return stack_dest - xstormy16_pc_size; |
| 306 | } |
| 307 | |
| 308 | /* Function: xstormy16_scan_prologue |
| 309 | Decode the instructions within the given address range. |
| 310 | Decide when we must have reached the end of the function prologue. |
| 311 | If a frame_info pointer is provided, fill in its saved_regs etc. |
| 312 | |
| 313 | Returns the address of the first instruction after the prologue. */ |
| 314 | |
| 315 | static CORE_ADDR |
| 316 | xstormy16_analyze_prologue (struct gdbarch *gdbarch, |
| 317 | CORE_ADDR start_addr, CORE_ADDR end_addr, |
| 318 | struct xstormy16_frame_cache *cache, |
| 319 | struct frame_info *this_frame) |
| 320 | { |
| 321 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 322 | CORE_ADDR next_addr; |
| 323 | ULONGEST inst, inst2; |
| 324 | LONGEST offset; |
| 325 | int regnum; |
| 326 | |
| 327 | /* Initialize framesize with size of PC put on stack by CALLF inst. */ |
| 328 | cache->saved_regs[E_PC_REGNUM] = 0; |
| 329 | cache->framesize = xstormy16_pc_size; |
| 330 | |
| 331 | if (start_addr >= end_addr) |
| 332 | return end_addr; |
| 333 | |
| 334 | for (next_addr = start_addr; |
| 335 | next_addr < end_addr; next_addr += xstormy16_inst_size) |
| 336 | { |
| 337 | inst = read_memory_unsigned_integer (next_addr, |
| 338 | xstormy16_inst_size, byte_order); |
| 339 | inst2 = read_memory_unsigned_integer (next_addr + xstormy16_inst_size, |
| 340 | xstormy16_inst_size, byte_order); |
| 341 | |
| 342 | if (inst >= 0x0082 && inst <= 0x008d) /* push r2 .. push r13 */ |
| 343 | { |
| 344 | regnum = inst & 0x000f; |
| 345 | cache->saved_regs[regnum] = cache->framesize; |
| 346 | cache->framesize += xstormy16_reg_size; |
| 347 | } |
| 348 | |
| 349 | /* Optional stack allocation for args and local vars <= 4 byte. */ |
| 350 | else if (inst == 0x301f || inst == 0x303f) /* inc r15, #0x1/#0x3 */ |
| 351 | { |
| 352 | cache->framesize += ((inst & 0x0030) >> 4) + 1; |
| 353 | } |
| 354 | |
| 355 | /* optional stack allocation for args and local vars > 4 && < 16 byte */ |
| 356 | else if ((inst & 0xff0f) == 0x510f) /* 51Hf add r15, #0xH */ |
| 357 | { |
| 358 | cache->framesize += (inst & 0x00f0) >> 4; |
| 359 | } |
| 360 | |
| 361 | /* Optional stack allocation for args and local vars >= 16 byte. */ |
| 362 | else if (inst == 0x314f && inst2 >= 0x0010) /* 314f HHHH add r15, #0xH */ |
| 363 | { |
| 364 | cache->framesize += inst2; |
| 365 | next_addr += xstormy16_inst_size; |
| 366 | } |
| 367 | |
| 368 | else if (inst == 0x46fd) /* mov r13, r15 */ |
| 369 | { |
| 370 | cache->uses_fp = 1; |
| 371 | } |
| 372 | |
| 373 | /* optional copying of args in r2-r7 to r10-r13. */ |
| 374 | /* Probably only in optimized case but legal action for prologue. */ |
| 375 | else if ((inst & 0xff00) == 0x4600 /* 46SD mov rD, rS */ |
| 376 | && (inst & 0x00f0) >= 0x0020 && (inst & 0x00f0) <= 0x0070 |
| 377 | && (inst & 0x000f) >= 0x000a && (inst & 0x000f) <= 0x000d) |
| 378 | ; |
| 379 | |
| 380 | /* Optional copying of args in r2-r7 to stack. */ |
| 381 | /* 72DS HHHH mov.b (rD, 0xHHHH), r(S-8) |
| 382 | (bit3 always 1, bit2-0 = reg) */ |
| 383 | /* 73DS HHHH mov.w (rD, 0xHHHH), r(S-8) */ |
| 384 | else if ((inst & 0xfed8) == 0x72d8 && (inst & 0x0007) >= 2) |
| 385 | { |
| 386 | regnum = inst & 0x0007; |
| 387 | /* Only 12 of 16 bits of the argument are used for the |
| 388 | signed offset. */ |
| 389 | offset = (LONGEST) (inst2 & 0x0fff); |
| 390 | if (offset & 0x0800) |
| 391 | offset -= 0x1000; |
| 392 | |
| 393 | cache->saved_regs[regnum] = cache->framesize + offset; |
| 394 | next_addr += xstormy16_inst_size; |
| 395 | } |
| 396 | |
| 397 | else /* Not a prologue instruction. */ |
| 398 | break; |
| 399 | } |
| 400 | |
| 401 | return next_addr; |
| 402 | } |
| 403 | |
| 404 | /* Function: xstormy16_skip_prologue |
| 405 | If the input address is in a function prologue, |
| 406 | returns the address of the end of the prologue; |
| 407 | else returns the input address. |
| 408 | |
| 409 | Note: the input address is likely to be the function start, |
| 410 | since this function is mainly used for advancing a breakpoint |
| 411 | to the first line, or stepping to the first line when we have |
| 412 | stepped into a function call. */ |
| 413 | |
| 414 | static CORE_ADDR |
| 415 | xstormy16_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 416 | { |
| 417 | CORE_ADDR func_addr = 0, func_end = 0; |
| 418 | const char *func_name; |
| 419 | |
| 420 | if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end)) |
| 421 | { |
| 422 | struct symtab_and_line sal; |
| 423 | struct symbol *sym; |
| 424 | struct xstormy16_frame_cache cache; |
| 425 | CORE_ADDR plg_end; |
| 426 | |
| 427 | memset (&cache, 0, sizeof cache); |
| 428 | |
| 429 | /* Don't trust line number debug info in frameless functions. */ |
| 430 | plg_end = xstormy16_analyze_prologue (gdbarch, func_addr, func_end, |
| 431 | &cache, NULL); |
| 432 | if (!cache.uses_fp) |
| 433 | return plg_end; |
| 434 | |
| 435 | /* Found a function. */ |
| 436 | sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL).symbol; |
| 437 | /* Don't use line number debug info for assembly source files. */ |
| 438 | if (sym && SYMBOL_LANGUAGE (sym) != language_asm) |
| 439 | { |
| 440 | sal = find_pc_line (func_addr, 0); |
| 441 | if (sal.end && sal.end < func_end) |
| 442 | { |
| 443 | /* Found a line number, use it as end of prologue. */ |
| 444 | return sal.end; |
| 445 | } |
| 446 | } |
| 447 | /* No useable line symbol. Use result of prologue parsing method. */ |
| 448 | return plg_end; |
| 449 | } |
| 450 | |
| 451 | /* No function symbol -- just return the PC. */ |
| 452 | |
| 453 | return (CORE_ADDR) pc; |
| 454 | } |
| 455 | |
| 456 | /* Implement the stack_frame_destroyed_p gdbarch method. |
| 457 | |
| 458 | The epilogue is defined here as the area at the end of a function, |
| 459 | either on the `ret' instruction itself or after an instruction which |
| 460 | destroys the function's stack frame. */ |
| 461 | |
| 462 | static int |
| 463 | xstormy16_stack_frame_destroyed_p (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 464 | { |
| 465 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 466 | CORE_ADDR func_addr = 0, func_end = 0; |
| 467 | |
| 468 | if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) |
| 469 | { |
| 470 | ULONGEST inst, inst2; |
| 471 | CORE_ADDR addr = func_end - xstormy16_inst_size; |
| 472 | |
| 473 | /* The Xstormy16 epilogue is max. 14 bytes long. */ |
| 474 | if (pc < func_end - 7 * xstormy16_inst_size) |
| 475 | return 0; |
| 476 | |
| 477 | /* Check if we're on a `ret' instruction. Otherwise it's |
| 478 | too dangerous to proceed. */ |
| 479 | inst = read_memory_unsigned_integer (addr, |
| 480 | xstormy16_inst_size, byte_order); |
| 481 | if (inst != 0x0003) |
| 482 | return 0; |
| 483 | |
| 484 | while ((addr -= xstormy16_inst_size) >= func_addr) |
| 485 | { |
| 486 | inst = read_memory_unsigned_integer (addr, |
| 487 | xstormy16_inst_size, |
| 488 | byte_order); |
| 489 | if (inst >= 0x009a && inst <= 0x009d) /* pop r10...r13 */ |
| 490 | continue; |
| 491 | if (inst == 0x305f || inst == 0x307f) /* dec r15, #0x1/#0x3 */ |
| 492 | break; |
| 493 | inst2 = read_memory_unsigned_integer (addr - xstormy16_inst_size, |
| 494 | xstormy16_inst_size, |
| 495 | byte_order); |
| 496 | if (inst2 == 0x314f && inst >= 0x8000) /* add r15, neg. value */ |
| 497 | { |
| 498 | addr -= xstormy16_inst_size; |
| 499 | break; |
| 500 | } |
| 501 | return 0; |
| 502 | } |
| 503 | if (pc > addr) |
| 504 | return 1; |
| 505 | } |
| 506 | return 0; |
| 507 | } |
| 508 | |
| 509 | constexpr gdb_byte xstormy16_break_insn[] = { 0x06, 0x0 }; |
| 510 | |
| 511 | typedef BP_MANIPULATION (xstormy16_break_insn) xstormy16_breakpoint; |
| 512 | |
| 513 | /* Given a pointer to a jump table entry, return the address |
| 514 | of the function it jumps to. Return 0 if not found. */ |
| 515 | static CORE_ADDR |
| 516 | xstormy16_resolve_jmp_table_entry (struct gdbarch *gdbarch, CORE_ADDR faddr) |
| 517 | { |
| 518 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 519 | struct obj_section *faddr_sect = find_pc_section (faddr); |
| 520 | |
| 521 | if (faddr_sect) |
| 522 | { |
| 523 | LONGEST inst, inst2, addr; |
| 524 | gdb_byte buf[2 * xstormy16_inst_size]; |
| 525 | |
| 526 | /* Return faddr if it's not pointing into the jump table. */ |
| 527 | if (strcmp (faddr_sect->the_bfd_section->name, ".plt")) |
| 528 | return faddr; |
| 529 | |
| 530 | if (!target_read_memory (faddr, buf, sizeof buf)) |
| 531 | { |
| 532 | inst = extract_unsigned_integer (buf, |
| 533 | xstormy16_inst_size, byte_order); |
| 534 | inst2 = extract_unsigned_integer (buf + xstormy16_inst_size, |
| 535 | xstormy16_inst_size, byte_order); |
| 536 | addr = inst2 << 8 | (inst & 0xff); |
| 537 | return addr; |
| 538 | } |
| 539 | } |
| 540 | return 0; |
| 541 | } |
| 542 | |
| 543 | /* Given a function's address, attempt to find (and return) the |
| 544 | address of the corresponding jump table entry. Return 0 if |
| 545 | not found. */ |
| 546 | static CORE_ADDR |
| 547 | xstormy16_find_jmp_table_entry (struct gdbarch *gdbarch, CORE_ADDR faddr) |
| 548 | { |
| 549 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 550 | struct obj_section *faddr_sect = find_pc_section (faddr); |
| 551 | |
| 552 | if (faddr_sect) |
| 553 | { |
| 554 | struct obj_section *osect; |
| 555 | |
| 556 | /* Return faddr if it's already a pointer to a jump table entry. */ |
| 557 | if (!strcmp (faddr_sect->the_bfd_section->name, ".plt")) |
| 558 | return faddr; |
| 559 | |
| 560 | ALL_OBJFILE_OSECTIONS (faddr_sect->objfile, osect) |
| 561 | { |
| 562 | if (!strcmp (osect->the_bfd_section->name, ".plt")) |
| 563 | break; |
| 564 | } |
| 565 | |
| 566 | if (osect < faddr_sect->objfile->sections_end) |
| 567 | { |
| 568 | CORE_ADDR addr, endaddr; |
| 569 | |
| 570 | addr = obj_section_addr (osect); |
| 571 | endaddr = obj_section_endaddr (osect); |
| 572 | |
| 573 | for (; addr < endaddr; addr += 2 * xstormy16_inst_size) |
| 574 | { |
| 575 | LONGEST inst, inst2, faddr2; |
| 576 | gdb_byte buf[2 * xstormy16_inst_size]; |
| 577 | |
| 578 | if (target_read_memory (addr, buf, sizeof buf)) |
| 579 | return 0; |
| 580 | inst = extract_unsigned_integer (buf, |
| 581 | xstormy16_inst_size, |
| 582 | byte_order); |
| 583 | inst2 = extract_unsigned_integer (buf + xstormy16_inst_size, |
| 584 | xstormy16_inst_size, |
| 585 | byte_order); |
| 586 | faddr2 = inst2 << 8 | (inst & 0xff); |
| 587 | if (faddr == faddr2) |
| 588 | return addr; |
| 589 | } |
| 590 | } |
| 591 | } |
| 592 | return 0; |
| 593 | } |
| 594 | |
| 595 | static CORE_ADDR |
| 596 | xstormy16_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) |
| 597 | { |
| 598 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 599 | CORE_ADDR tmp = xstormy16_resolve_jmp_table_entry (gdbarch, pc); |
| 600 | |
| 601 | if (tmp && tmp != pc) |
| 602 | return tmp; |
| 603 | return 0; |
| 604 | } |
| 605 | |
| 606 | /* Function pointers are 16 bit. The address space is 24 bit, using |
| 607 | 32 bit addresses. Pointers to functions on the XStormy16 are implemented |
| 608 | by using 16 bit pointers, which are either direct pointers in case the |
| 609 | function begins below 0x10000, or indirect pointers into a jump table. |
| 610 | The next two functions convert 16 bit pointers into 24 (32) bit addresses |
| 611 | and vice versa. */ |
| 612 | |
| 613 | static CORE_ADDR |
| 614 | xstormy16_pointer_to_address (struct gdbarch *gdbarch, |
| 615 | struct type *type, const gdb_byte *buf) |
| 616 | { |
| 617 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 618 | enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type)); |
| 619 | CORE_ADDR addr |
| 620 | = extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order); |
| 621 | |
| 622 | if (target == TYPE_CODE_FUNC || target == TYPE_CODE_METHOD) |
| 623 | { |
| 624 | CORE_ADDR addr2 = xstormy16_resolve_jmp_table_entry (gdbarch, addr); |
| 625 | if (addr2) |
| 626 | addr = addr2; |
| 627 | } |
| 628 | |
| 629 | return addr; |
| 630 | } |
| 631 | |
| 632 | static void |
| 633 | xstormy16_address_to_pointer (struct gdbarch *gdbarch, |
| 634 | struct type *type, gdb_byte *buf, CORE_ADDR addr) |
| 635 | { |
| 636 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 637 | enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type)); |
| 638 | |
| 639 | if (target == TYPE_CODE_FUNC || target == TYPE_CODE_METHOD) |
| 640 | { |
| 641 | CORE_ADDR addr2 = xstormy16_find_jmp_table_entry (gdbarch, addr); |
| 642 | if (addr2) |
| 643 | addr = addr2; |
| 644 | } |
| 645 | store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order, addr); |
| 646 | } |
| 647 | |
| 648 | static struct xstormy16_frame_cache * |
| 649 | xstormy16_alloc_frame_cache (void) |
| 650 | { |
| 651 | struct xstormy16_frame_cache *cache; |
| 652 | int i; |
| 653 | |
| 654 | cache = FRAME_OBSTACK_ZALLOC (struct xstormy16_frame_cache); |
| 655 | |
| 656 | cache->base = 0; |
| 657 | cache->saved_sp = 0; |
| 658 | cache->pc = 0; |
| 659 | cache->uses_fp = 0; |
| 660 | cache->framesize = 0; |
| 661 | for (i = 0; i < E_NUM_REGS; ++i) |
| 662 | cache->saved_regs[i] = REG_UNAVAIL; |
| 663 | |
| 664 | return cache; |
| 665 | } |
| 666 | |
| 667 | static struct xstormy16_frame_cache * |
| 668 | xstormy16_frame_cache (struct frame_info *this_frame, void **this_cache) |
| 669 | { |
| 670 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 671 | struct xstormy16_frame_cache *cache; |
| 672 | CORE_ADDR current_pc; |
| 673 | int i; |
| 674 | |
| 675 | if (*this_cache) |
| 676 | return (struct xstormy16_frame_cache *) *this_cache; |
| 677 | |
| 678 | cache = xstormy16_alloc_frame_cache (); |
| 679 | *this_cache = cache; |
| 680 | |
| 681 | cache->base = get_frame_register_unsigned (this_frame, E_FP_REGNUM); |
| 682 | if (cache->base == 0) |
| 683 | return cache; |
| 684 | |
| 685 | cache->pc = get_frame_func (this_frame); |
| 686 | current_pc = get_frame_pc (this_frame); |
| 687 | if (cache->pc) |
| 688 | xstormy16_analyze_prologue (gdbarch, cache->pc, current_pc, |
| 689 | cache, this_frame); |
| 690 | |
| 691 | if (!cache->uses_fp) |
| 692 | cache->base = get_frame_register_unsigned (this_frame, E_SP_REGNUM); |
| 693 | |
| 694 | cache->saved_sp = cache->base - cache->framesize; |
| 695 | |
| 696 | for (i = 0; i < E_NUM_REGS; ++i) |
| 697 | if (cache->saved_regs[i] != REG_UNAVAIL) |
| 698 | cache->saved_regs[i] += cache->saved_sp; |
| 699 | |
| 700 | return cache; |
| 701 | } |
| 702 | |
| 703 | static struct value * |
| 704 | xstormy16_frame_prev_register (struct frame_info *this_frame, |
| 705 | void **this_cache, int regnum) |
| 706 | { |
| 707 | struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame, |
| 708 | this_cache); |
| 709 | gdb_assert (regnum >= 0); |
| 710 | |
| 711 | if (regnum == E_SP_REGNUM && cache->saved_sp) |
| 712 | return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp); |
| 713 | |
| 714 | if (regnum < E_NUM_REGS && cache->saved_regs[regnum] != REG_UNAVAIL) |
| 715 | return frame_unwind_got_memory (this_frame, regnum, |
| 716 | cache->saved_regs[regnum]); |
| 717 | |
| 718 | return frame_unwind_got_register (this_frame, regnum, regnum); |
| 719 | } |
| 720 | |
| 721 | static void |
| 722 | xstormy16_frame_this_id (struct frame_info *this_frame, void **this_cache, |
| 723 | struct frame_id *this_id) |
| 724 | { |
| 725 | struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame, |
| 726 | this_cache); |
| 727 | |
| 728 | /* This marks the outermost frame. */ |
| 729 | if (cache->base == 0) |
| 730 | return; |
| 731 | |
| 732 | *this_id = frame_id_build (cache->saved_sp, cache->pc); |
| 733 | } |
| 734 | |
| 735 | static CORE_ADDR |
| 736 | xstormy16_frame_base_address (struct frame_info *this_frame, void **this_cache) |
| 737 | { |
| 738 | struct xstormy16_frame_cache *cache = xstormy16_frame_cache (this_frame, |
| 739 | this_cache); |
| 740 | return cache->base; |
| 741 | } |
| 742 | |
| 743 | static const struct frame_unwind xstormy16_frame_unwind = { |
| 744 | NORMAL_FRAME, |
| 745 | default_frame_unwind_stop_reason, |
| 746 | xstormy16_frame_this_id, |
| 747 | xstormy16_frame_prev_register, |
| 748 | NULL, |
| 749 | default_frame_sniffer |
| 750 | }; |
| 751 | |
| 752 | static const struct frame_base xstormy16_frame_base = { |
| 753 | &xstormy16_frame_unwind, |
| 754 | xstormy16_frame_base_address, |
| 755 | xstormy16_frame_base_address, |
| 756 | xstormy16_frame_base_address |
| 757 | }; |
| 758 | |
| 759 | static CORE_ADDR |
| 760 | xstormy16_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 761 | { |
| 762 | return frame_unwind_register_unsigned (next_frame, E_SP_REGNUM); |
| 763 | } |
| 764 | |
| 765 | static CORE_ADDR |
| 766 | xstormy16_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 767 | { |
| 768 | return frame_unwind_register_unsigned (next_frame, E_PC_REGNUM); |
| 769 | } |
| 770 | |
| 771 | static struct frame_id |
| 772 | xstormy16_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 773 | { |
| 774 | CORE_ADDR sp = get_frame_register_unsigned (this_frame, E_SP_REGNUM); |
| 775 | return frame_id_build (sp, get_frame_pc (this_frame)); |
| 776 | } |
| 777 | |
| 778 | |
| 779 | /* Function: xstormy16_gdbarch_init |
| 780 | Initializer function for the xstormy16 gdbarch vector. |
| 781 | Called by gdbarch. Sets up the gdbarch vector(s) for this target. */ |
| 782 | |
| 783 | static struct gdbarch * |
| 784 | xstormy16_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| 785 | { |
| 786 | struct gdbarch *gdbarch; |
| 787 | |
| 788 | /* find a candidate among the list of pre-declared architectures. */ |
| 789 | arches = gdbarch_list_lookup_by_info (arches, &info); |
| 790 | if (arches != NULL) |
| 791 | return (arches->gdbarch); |
| 792 | |
| 793 | gdbarch = gdbarch_alloc (&info, NULL); |
| 794 | |
| 795 | /* |
| 796 | * Basic register fields and methods, datatype sizes and stuff. |
| 797 | */ |
| 798 | |
| 799 | set_gdbarch_num_regs (gdbarch, E_NUM_REGS); |
| 800 | set_gdbarch_num_pseudo_regs (gdbarch, 0); |
| 801 | set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM); |
| 802 | set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM); |
| 803 | set_gdbarch_register_name (gdbarch, xstormy16_register_name); |
| 804 | set_gdbarch_register_type (gdbarch, xstormy16_register_type); |
| 805 | |
| 806 | set_gdbarch_char_signed (gdbarch, 0); |
| 807 | set_gdbarch_short_bit (gdbarch, 2 * TARGET_CHAR_BIT); |
| 808 | set_gdbarch_int_bit (gdbarch, 2 * TARGET_CHAR_BIT); |
| 809 | set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT); |
| 810 | set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT); |
| 811 | |
| 812 | set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT); |
| 813 | set_gdbarch_double_bit (gdbarch, 8 * TARGET_CHAR_BIT); |
| 814 | set_gdbarch_long_double_bit (gdbarch, 8 * TARGET_CHAR_BIT); |
| 815 | |
| 816 | set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT); |
| 817 | set_gdbarch_addr_bit (gdbarch, 4 * TARGET_CHAR_BIT); |
| 818 | set_gdbarch_dwarf2_addr_size (gdbarch, 4); |
| 819 | |
| 820 | set_gdbarch_address_to_pointer (gdbarch, xstormy16_address_to_pointer); |
| 821 | set_gdbarch_pointer_to_address (gdbarch, xstormy16_pointer_to_address); |
| 822 | |
| 823 | /* Stack grows up. */ |
| 824 | set_gdbarch_inner_than (gdbarch, core_addr_greaterthan); |
| 825 | |
| 826 | /* |
| 827 | * Frame Info |
| 828 | */ |
| 829 | set_gdbarch_unwind_sp (gdbarch, xstormy16_unwind_sp); |
| 830 | set_gdbarch_unwind_pc (gdbarch, xstormy16_unwind_pc); |
| 831 | set_gdbarch_dummy_id (gdbarch, xstormy16_dummy_id); |
| 832 | set_gdbarch_frame_align (gdbarch, xstormy16_frame_align); |
| 833 | frame_base_set_default (gdbarch, &xstormy16_frame_base); |
| 834 | |
| 835 | set_gdbarch_skip_prologue (gdbarch, xstormy16_skip_prologue); |
| 836 | set_gdbarch_stack_frame_destroyed_p (gdbarch, |
| 837 | xstormy16_stack_frame_destroyed_p); |
| 838 | |
| 839 | /* These values and methods are used when gdb calls a target function. */ |
| 840 | set_gdbarch_push_dummy_call (gdbarch, xstormy16_push_dummy_call); |
| 841 | set_gdbarch_breakpoint_kind_from_pc (gdbarch, |
| 842 | xstormy16_breakpoint::kind_from_pc); |
| 843 | set_gdbarch_sw_breakpoint_from_kind (gdbarch, |
| 844 | xstormy16_breakpoint::bp_from_kind); |
| 845 | set_gdbarch_return_value (gdbarch, xstormy16_return_value); |
| 846 | |
| 847 | set_gdbarch_skip_trampoline_code (gdbarch, xstormy16_skip_trampoline_code); |
| 848 | |
| 849 | set_gdbarch_print_insn (gdbarch, print_insn_xstormy16); |
| 850 | |
| 851 | gdbarch_init_osabi (info, gdbarch); |
| 852 | |
| 853 | dwarf2_append_unwinders (gdbarch); |
| 854 | frame_unwind_append_unwinder (gdbarch, &xstormy16_frame_unwind); |
| 855 | |
| 856 | return gdbarch; |
| 857 | } |
| 858 | |
| 859 | /* Function: _initialize_xstormy16_tdep |
| 860 | Initializer function for the Sanyo Xstormy16a module. |
| 861 | Called by gdb at start-up. */ |
| 862 | |
| 863 | /* -Wmissing-prototypes */ |
| 864 | extern initialize_file_ftype _initialize_xstormy16_tdep; |
| 865 | |
| 866 | void |
| 867 | _initialize_xstormy16_tdep (void) |
| 868 | { |
| 869 | register_gdbarch_init (bfd_arch_xstormy16, xstormy16_gdbarch_init); |
| 870 | } |