| 1 | /* Target-dependent code for the Texas Instruments MSP430 for GDB, the |
| 2 | GNU debugger. |
| 3 | |
| 4 | Copyright (C) 2012-2015 Free Software Foundation, Inc. |
| 5 | |
| 6 | Contributed by Red Hat, Inc. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "arch-utils.h" |
| 25 | #include "prologue-value.h" |
| 26 | #include "target.h" |
| 27 | #include "regcache.h" |
| 28 | #include "dis-asm.h" |
| 29 | #include "gdbtypes.h" |
| 30 | #include "frame.h" |
| 31 | #include "frame-unwind.h" |
| 32 | #include "frame-base.h" |
| 33 | #include "value.h" |
| 34 | #include "gdbcore.h" |
| 35 | #include "dwarf2-frame.h" |
| 36 | #include "reggroups.h" |
| 37 | |
| 38 | #include "elf/msp430.h" |
| 39 | #include "opcode/msp430-decode.h" |
| 40 | #include "elf-bfd.h" |
| 41 | |
| 42 | /* Register Numbers. */ |
| 43 | |
| 44 | enum |
| 45 | { |
| 46 | MSP430_PC_RAW_REGNUM, |
| 47 | MSP430_SP_RAW_REGNUM, |
| 48 | MSP430_SR_RAW_REGNUM, |
| 49 | MSP430_CG_RAW_REGNUM, |
| 50 | MSP430_R4_RAW_REGNUM, |
| 51 | MSP430_R5_RAW_REGNUM, |
| 52 | MSP430_R6_RAW_REGNUM, |
| 53 | MSP430_R7_RAW_REGNUM, |
| 54 | MSP430_R8_RAW_REGNUM, |
| 55 | MSP430_R9_RAW_REGNUM, |
| 56 | MSP430_R10_RAW_REGNUM, |
| 57 | MSP430_R11_RAW_REGNUM, |
| 58 | MSP430_R12_RAW_REGNUM, |
| 59 | MSP430_R13_RAW_REGNUM, |
| 60 | MSP430_R14_RAW_REGNUM, |
| 61 | MSP430_R15_RAW_REGNUM, |
| 62 | |
| 63 | MSP430_NUM_REGS, |
| 64 | |
| 65 | MSP430_PC_REGNUM = MSP430_NUM_REGS, |
| 66 | MSP430_SP_REGNUM, |
| 67 | MSP430_SR_REGNUM, |
| 68 | MSP430_CG_REGNUM, |
| 69 | MSP430_R4_REGNUM, |
| 70 | MSP430_R5_REGNUM, |
| 71 | MSP430_R6_REGNUM, |
| 72 | MSP430_R7_REGNUM, |
| 73 | MSP430_R8_REGNUM, |
| 74 | MSP430_R9_REGNUM, |
| 75 | MSP430_R10_REGNUM, |
| 76 | MSP430_R11_REGNUM, |
| 77 | MSP430_R12_REGNUM, |
| 78 | MSP430_R13_REGNUM, |
| 79 | MSP430_R14_REGNUM, |
| 80 | MSP430_R15_REGNUM, |
| 81 | |
| 82 | MSP430_NUM_TOTAL_REGS, |
| 83 | MSP430_NUM_PSEUDO_REGS = MSP430_NUM_TOTAL_REGS - MSP430_NUM_REGS |
| 84 | }; |
| 85 | |
| 86 | enum |
| 87 | { |
| 88 | /* TI MSP430 Architecture. */ |
| 89 | MSP_ISA_MSP430, |
| 90 | |
| 91 | /* TI MSP430X Architecture. */ |
| 92 | MSP_ISA_MSP430X |
| 93 | }; |
| 94 | |
| 95 | enum |
| 96 | { |
| 97 | /* The small code model limits code addresses to 16 bits. */ |
| 98 | MSP_SMALL_CODE_MODEL, |
| 99 | |
| 100 | /* The large code model uses 20 bit addresses for function |
| 101 | pointers. These are stored in memory using four bytes (32 bits). */ |
| 102 | MSP_LARGE_CODE_MODEL |
| 103 | }; |
| 104 | |
| 105 | /* Architecture specific data. */ |
| 106 | |
| 107 | struct gdbarch_tdep |
| 108 | { |
| 109 | /* The ELF header flags specify the multilib used. */ |
| 110 | int elf_flags; |
| 111 | |
| 112 | /* One of MSP_ISA_MSP430 or MSP_ISA_MSP430X. */ |
| 113 | int isa; |
| 114 | |
| 115 | /* One of MSP_SMALL_CODE_MODEL or MSP_LARGE_CODE_MODEL. If, at |
| 116 | some point, we support different data models too, we'll probably |
| 117 | structure things so that we can combine values using logical |
| 118 | "or". */ |
| 119 | int code_model; |
| 120 | }; |
| 121 | |
| 122 | /* This structure holds the results of a prologue analysis. */ |
| 123 | |
| 124 | struct msp430_prologue |
| 125 | { |
| 126 | /* The offset from the frame base to the stack pointer --- always |
| 127 | zero or negative. |
| 128 | |
| 129 | Calling this a "size" is a bit misleading, but given that the |
| 130 | stack grows downwards, using offsets for everything keeps one |
| 131 | from going completely sign-crazy: you never change anything's |
| 132 | sign for an ADD instruction; always change the second operand's |
| 133 | sign for a SUB instruction; and everything takes care of |
| 134 | itself. */ |
| 135 | int frame_size; |
| 136 | |
| 137 | /* Non-zero if this function has initialized the frame pointer from |
| 138 | the stack pointer, zero otherwise. */ |
| 139 | int has_frame_ptr; |
| 140 | |
| 141 | /* If has_frame_ptr is non-zero, this is the offset from the frame |
| 142 | base to where the frame pointer points. This is always zero or |
| 143 | negative. */ |
| 144 | int frame_ptr_offset; |
| 145 | |
| 146 | /* The address of the first instruction at which the frame has been |
| 147 | set up and the arguments are where the debug info says they are |
| 148 | --- as best as we can tell. */ |
| 149 | CORE_ADDR prologue_end; |
| 150 | |
| 151 | /* reg_offset[R] is the offset from the CFA at which register R is |
| 152 | saved, or 1 if register R has not been saved. (Real values are |
| 153 | always zero or negative.) */ |
| 154 | int reg_offset[MSP430_NUM_TOTAL_REGS]; |
| 155 | }; |
| 156 | |
| 157 | /* Implement the "register_type" gdbarch method. */ |
| 158 | |
| 159 | static struct type * |
| 160 | msp430_register_type (struct gdbarch *gdbarch, int reg_nr) |
| 161 | { |
| 162 | if (reg_nr < MSP430_NUM_REGS) |
| 163 | return builtin_type (gdbarch)->builtin_uint32; |
| 164 | else if (reg_nr == MSP430_PC_REGNUM) |
| 165 | return builtin_type (gdbarch)->builtin_func_ptr; |
| 166 | else |
| 167 | return builtin_type (gdbarch)->builtin_uint16; |
| 168 | } |
| 169 | |
| 170 | /* Implement another version of the "register_type" gdbarch method |
| 171 | for msp430x. */ |
| 172 | |
| 173 | static struct type * |
| 174 | msp430x_register_type (struct gdbarch *gdbarch, int reg_nr) |
| 175 | { |
| 176 | if (reg_nr < MSP430_NUM_REGS) |
| 177 | return builtin_type (gdbarch)->builtin_uint32; |
| 178 | else if (reg_nr == MSP430_PC_REGNUM) |
| 179 | return builtin_type (gdbarch)->builtin_func_ptr; |
| 180 | else |
| 181 | return builtin_type (gdbarch)->builtin_uint32; |
| 182 | } |
| 183 | |
| 184 | /* Implement the "register_name" gdbarch method. */ |
| 185 | |
| 186 | static const char * |
| 187 | msp430_register_name (struct gdbarch *gdbarch, int regnr) |
| 188 | { |
| 189 | static const char *const reg_names[] = { |
| 190 | /* Raw registers. */ |
| 191 | "", "", "", "", "", "", "", "", |
| 192 | "", "", "", "", "", "", "", "", |
| 193 | /* Pseudo registers. */ |
| 194 | "pc", "sp", "sr", "cg", "r4", "r5", "r6", "r7", |
| 195 | "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15" |
| 196 | }; |
| 197 | |
| 198 | return reg_names[regnr]; |
| 199 | } |
| 200 | |
| 201 | /* Implement the "register_reggroup_p" gdbarch method. */ |
| 202 | |
| 203 | static int |
| 204 | msp430_register_reggroup_p (struct gdbarch *gdbarch, int regnum, |
| 205 | struct reggroup *group) |
| 206 | { |
| 207 | if (group == all_reggroup) |
| 208 | return 1; |
| 209 | |
| 210 | /* All other registers are saved and restored. */ |
| 211 | if (group == save_reggroup || group == restore_reggroup) |
| 212 | return (MSP430_NUM_REGS <= regnum && regnum < MSP430_NUM_TOTAL_REGS); |
| 213 | |
| 214 | return group == general_reggroup; |
| 215 | } |
| 216 | |
| 217 | /* Implement the "pseudo_register_read" gdbarch method. */ |
| 218 | |
| 219 | static enum register_status |
| 220 | msp430_pseudo_register_read (struct gdbarch *gdbarch, |
| 221 | struct regcache *regcache, |
| 222 | int regnum, gdb_byte *buffer) |
| 223 | { |
| 224 | enum register_status status = REG_UNKNOWN; |
| 225 | |
| 226 | if (MSP430_NUM_REGS <= regnum && regnum < MSP430_NUM_TOTAL_REGS) |
| 227 | { |
| 228 | ULONGEST val; |
| 229 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 230 | int regsize = register_size (gdbarch, regnum); |
| 231 | int raw_regnum = regnum - MSP430_NUM_REGS; |
| 232 | |
| 233 | status = regcache_raw_read_unsigned (regcache, raw_regnum, &val); |
| 234 | if (status == REG_VALID) |
| 235 | store_unsigned_integer (buffer, regsize, byte_order, val); |
| 236 | |
| 237 | } |
| 238 | else |
| 239 | gdb_assert_not_reached ("invalid pseudo register number"); |
| 240 | |
| 241 | return status; |
| 242 | } |
| 243 | |
| 244 | /* Implement the "pseudo_register_write" gdbarch method. */ |
| 245 | |
| 246 | static void |
| 247 | msp430_pseudo_register_write (struct gdbarch *gdbarch, |
| 248 | struct regcache *regcache, |
| 249 | int regnum, const gdb_byte *buffer) |
| 250 | { |
| 251 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 252 | if (MSP430_NUM_REGS <= regnum && regnum < MSP430_NUM_TOTAL_REGS) |
| 253 | |
| 254 | { |
| 255 | ULONGEST val; |
| 256 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 257 | int regsize = register_size (gdbarch, regnum); |
| 258 | int raw_regnum = regnum - MSP430_NUM_REGS; |
| 259 | |
| 260 | val = extract_unsigned_integer (buffer, regsize, byte_order); |
| 261 | regcache_raw_write_unsigned (regcache, raw_regnum, val); |
| 262 | |
| 263 | } |
| 264 | else |
| 265 | gdb_assert_not_reached ("invalid pseudo register number"); |
| 266 | } |
| 267 | |
| 268 | /* Implement the `register_sim_regno' gdbarch method. */ |
| 269 | |
| 270 | static int |
| 271 | msp430_register_sim_regno (struct gdbarch *gdbarch, int regnum) |
| 272 | { |
| 273 | gdb_assert (regnum < MSP430_NUM_REGS); |
| 274 | |
| 275 | /* So long as regnum is in [0, RL78_NUM_REGS), it's valid. We |
| 276 | just want to override the default here which disallows register |
| 277 | numbers which have no names. */ |
| 278 | return regnum; |
| 279 | } |
| 280 | |
| 281 | /* Implement the "breakpoint_from_pc" gdbarch method. */ |
| 282 | |
| 283 | static const gdb_byte * |
| 284 | msp430_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr, |
| 285 | int *lenptr) |
| 286 | { |
| 287 | static gdb_byte breakpoint[] = { 0x43, 0x43 }; |
| 288 | |
| 289 | *lenptr = sizeof breakpoint; |
| 290 | return breakpoint; |
| 291 | } |
| 292 | |
| 293 | /* Define a "handle" struct for fetching the next opcode. */ |
| 294 | |
| 295 | struct msp430_get_opcode_byte_handle |
| 296 | { |
| 297 | CORE_ADDR pc; |
| 298 | }; |
| 299 | |
| 300 | /* Fetch a byte on behalf of the opcode decoder. HANDLE contains |
| 301 | the memory address of the next byte to fetch. If successful, |
| 302 | the address in the handle is updated and the byte fetched is |
| 303 | returned as the value of the function. If not successful, -1 |
| 304 | is returned. */ |
| 305 | |
| 306 | static int |
| 307 | msp430_get_opcode_byte (void *handle) |
| 308 | { |
| 309 | struct msp430_get_opcode_byte_handle *opcdata = handle; |
| 310 | int status; |
| 311 | gdb_byte byte; |
| 312 | |
| 313 | status = target_read_memory (opcdata->pc, &byte, 1); |
| 314 | if (status == 0) |
| 315 | { |
| 316 | opcdata->pc += 1; |
| 317 | return byte; |
| 318 | } |
| 319 | else |
| 320 | return -1; |
| 321 | } |
| 322 | |
| 323 | /* Function for finding saved registers in a 'struct pv_area'; this |
| 324 | function is passed to pv_area_scan. |
| 325 | |
| 326 | If VALUE is a saved register, ADDR says it was saved at a constant |
| 327 | offset from the frame base, and SIZE indicates that the whole |
| 328 | register was saved, record its offset. */ |
| 329 | |
| 330 | static void |
| 331 | check_for_saved (void *result_untyped, pv_t addr, CORE_ADDR size, pv_t value) |
| 332 | { |
| 333 | struct msp430_prologue *result = (struct msp430_prologue *) result_untyped; |
| 334 | |
| 335 | if (value.kind == pvk_register |
| 336 | && value.k == 0 |
| 337 | && pv_is_register (addr, MSP430_SP_REGNUM) |
| 338 | && size == register_size (target_gdbarch (), value.reg)) |
| 339 | result->reg_offset[value.reg] = addr.k; |
| 340 | } |
| 341 | |
| 342 | /* Analyze a prologue starting at START_PC, going no further than |
| 343 | LIMIT_PC. Fill in RESULT as appropriate. */ |
| 344 | |
| 345 | static void |
| 346 | msp430_analyze_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc, |
| 347 | CORE_ADDR limit_pc, struct msp430_prologue *result) |
| 348 | { |
| 349 | CORE_ADDR pc, next_pc; |
| 350 | int rn; |
| 351 | pv_t reg[MSP430_NUM_TOTAL_REGS]; |
| 352 | struct pv_area *stack; |
| 353 | struct cleanup *back_to; |
| 354 | CORE_ADDR after_last_frame_setup_insn = start_pc; |
| 355 | int code_model = gdbarch_tdep (gdbarch)->code_model; |
| 356 | int sz; |
| 357 | |
| 358 | memset (result, 0, sizeof (*result)); |
| 359 | |
| 360 | for (rn = 0; rn < MSP430_NUM_TOTAL_REGS; rn++) |
| 361 | { |
| 362 | reg[rn] = pv_register (rn, 0); |
| 363 | result->reg_offset[rn] = 1; |
| 364 | } |
| 365 | |
| 366 | stack = make_pv_area (MSP430_SP_REGNUM, gdbarch_addr_bit (gdbarch)); |
| 367 | back_to = make_cleanup_free_pv_area (stack); |
| 368 | |
| 369 | /* The call instruction has saved the return address on the stack. */ |
| 370 | sz = code_model == MSP_LARGE_CODE_MODEL ? 4 : 2; |
| 371 | reg[MSP430_SP_REGNUM] = pv_add_constant (reg[MSP430_SP_REGNUM], -sz); |
| 372 | pv_area_store (stack, reg[MSP430_SP_REGNUM], sz, reg[MSP430_PC_REGNUM]); |
| 373 | |
| 374 | pc = start_pc; |
| 375 | while (pc < limit_pc) |
| 376 | { |
| 377 | int bytes_read; |
| 378 | struct msp430_get_opcode_byte_handle opcode_handle; |
| 379 | MSP430_Opcode_Decoded opc; |
| 380 | |
| 381 | opcode_handle.pc = pc; |
| 382 | bytes_read = msp430_decode_opcode (pc, &opc, msp430_get_opcode_byte, |
| 383 | &opcode_handle); |
| 384 | next_pc = pc + bytes_read; |
| 385 | |
| 386 | if (opc.id == MSO_push && opc.op[0].type == MSP430_Operand_Register) |
| 387 | { |
| 388 | int rsrc = opc.op[0].reg; |
| 389 | |
| 390 | reg[MSP430_SP_REGNUM] = pv_add_constant (reg[MSP430_SP_REGNUM], -2); |
| 391 | pv_area_store (stack, reg[MSP430_SP_REGNUM], 2, reg[rsrc]); |
| 392 | after_last_frame_setup_insn = next_pc; |
| 393 | } |
| 394 | else if (opc.id == MSO_push /* PUSHM */ |
| 395 | && opc.op[0].type == MSP430_Operand_None |
| 396 | && opc.op[1].type == MSP430_Operand_Register) |
| 397 | { |
| 398 | int rsrc = opc.op[1].reg; |
| 399 | int count = opc.repeats + 1; |
| 400 | int size = opc.size == 16 ? 2 : 4; |
| 401 | |
| 402 | while (count > 0) |
| 403 | { |
| 404 | reg[MSP430_SP_REGNUM] |
| 405 | = pv_add_constant (reg[MSP430_SP_REGNUM], -size); |
| 406 | pv_area_store (stack, reg[MSP430_SP_REGNUM], size, reg[rsrc]); |
| 407 | rsrc--; |
| 408 | count--; |
| 409 | } |
| 410 | after_last_frame_setup_insn = next_pc; |
| 411 | } |
| 412 | else if (opc.id == MSO_sub |
| 413 | && opc.op[0].type == MSP430_Operand_Register |
| 414 | && opc.op[0].reg == MSR_SP |
| 415 | && opc.op[1].type == MSP430_Operand_Immediate) |
| 416 | { |
| 417 | int addend = opc.op[1].addend; |
| 418 | |
| 419 | reg[MSP430_SP_REGNUM] = pv_add_constant (reg[MSP430_SP_REGNUM], |
| 420 | -addend); |
| 421 | after_last_frame_setup_insn = next_pc; |
| 422 | } |
| 423 | else if (opc.id == MSO_mov |
| 424 | && opc.op[0].type == MSP430_Operand_Immediate |
| 425 | && 12 <= opc.op[0].reg && opc.op[0].reg <= 15) |
| 426 | after_last_frame_setup_insn = next_pc; |
| 427 | else |
| 428 | { |
| 429 | /* Terminate the prologue scan. */ |
| 430 | break; |
| 431 | } |
| 432 | |
| 433 | pc = next_pc; |
| 434 | } |
| 435 | |
| 436 | /* Is the frame size (offset, really) a known constant? */ |
| 437 | if (pv_is_register (reg[MSP430_SP_REGNUM], MSP430_SP_REGNUM)) |
| 438 | result->frame_size = reg[MSP430_SP_REGNUM].k; |
| 439 | |
| 440 | /* Record where all the registers were saved. */ |
| 441 | pv_area_scan (stack, check_for_saved, result); |
| 442 | |
| 443 | result->prologue_end = after_last_frame_setup_insn; |
| 444 | |
| 445 | do_cleanups (back_to); |
| 446 | } |
| 447 | |
| 448 | /* Implement the "skip_prologue" gdbarch method. */ |
| 449 | |
| 450 | static CORE_ADDR |
| 451 | msp430_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 452 | { |
| 453 | const char *name; |
| 454 | CORE_ADDR func_addr, func_end; |
| 455 | struct msp430_prologue p; |
| 456 | |
| 457 | /* Try to find the extent of the function that contains PC. */ |
| 458 | if (!find_pc_partial_function (pc, &name, &func_addr, &func_end)) |
| 459 | return pc; |
| 460 | |
| 461 | msp430_analyze_prologue (gdbarch, pc, func_end, &p); |
| 462 | return p.prologue_end; |
| 463 | } |
| 464 | |
| 465 | /* Implement the "unwind_pc" gdbarch method. */ |
| 466 | |
| 467 | static CORE_ADDR |
| 468 | msp430_unwind_pc (struct gdbarch *arch, struct frame_info *next_frame) |
| 469 | { |
| 470 | return frame_unwind_register_unsigned (next_frame, MSP430_PC_REGNUM); |
| 471 | } |
| 472 | |
| 473 | /* Implement the "unwind_sp" gdbarch method. */ |
| 474 | |
| 475 | static CORE_ADDR |
| 476 | msp430_unwind_sp (struct gdbarch *arch, struct frame_info *next_frame) |
| 477 | { |
| 478 | return frame_unwind_register_unsigned (next_frame, MSP430_SP_REGNUM); |
| 479 | } |
| 480 | |
| 481 | /* Given a frame described by THIS_FRAME, decode the prologue of its |
| 482 | associated function if there is not cache entry as specified by |
| 483 | THIS_PROLOGUE_CACHE. Save the decoded prologue in the cache and |
| 484 | return that struct as the value of this function. */ |
| 485 | |
| 486 | static struct msp430_prologue * |
| 487 | msp430_analyze_frame_prologue (struct frame_info *this_frame, |
| 488 | void **this_prologue_cache) |
| 489 | { |
| 490 | if (!*this_prologue_cache) |
| 491 | { |
| 492 | CORE_ADDR func_start, stop_addr; |
| 493 | |
| 494 | *this_prologue_cache = FRAME_OBSTACK_ZALLOC (struct msp430_prologue); |
| 495 | |
| 496 | func_start = get_frame_func (this_frame); |
| 497 | stop_addr = get_frame_pc (this_frame); |
| 498 | |
| 499 | /* If we couldn't find any function containing the PC, then |
| 500 | just initialize the prologue cache, but don't do anything. */ |
| 501 | if (!func_start) |
| 502 | stop_addr = func_start; |
| 503 | |
| 504 | msp430_analyze_prologue (get_frame_arch (this_frame), func_start, |
| 505 | stop_addr, *this_prologue_cache); |
| 506 | } |
| 507 | |
| 508 | return *this_prologue_cache; |
| 509 | } |
| 510 | |
| 511 | /* Given a frame and a prologue cache, return this frame's base. */ |
| 512 | |
| 513 | static CORE_ADDR |
| 514 | msp430_frame_base (struct frame_info *this_frame, void **this_prologue_cache) |
| 515 | { |
| 516 | struct msp430_prologue *p |
| 517 | = msp430_analyze_frame_prologue (this_frame, this_prologue_cache); |
| 518 | CORE_ADDR sp = get_frame_register_unsigned (this_frame, MSP430_SP_REGNUM); |
| 519 | |
| 520 | return sp - p->frame_size; |
| 521 | } |
| 522 | |
| 523 | /* Implement the "frame_this_id" method for unwinding frames. */ |
| 524 | |
| 525 | static void |
| 526 | msp430_this_id (struct frame_info *this_frame, |
| 527 | void **this_prologue_cache, struct frame_id *this_id) |
| 528 | { |
| 529 | *this_id = frame_id_build (msp430_frame_base (this_frame, |
| 530 | this_prologue_cache), |
| 531 | get_frame_func (this_frame)); |
| 532 | } |
| 533 | |
| 534 | /* Implement the "frame_prev_register" method for unwinding frames. */ |
| 535 | |
| 536 | static struct value * |
| 537 | msp430_prev_register (struct frame_info *this_frame, |
| 538 | void **this_prologue_cache, int regnum) |
| 539 | { |
| 540 | struct msp430_prologue *p |
| 541 | = msp430_analyze_frame_prologue (this_frame, this_prologue_cache); |
| 542 | CORE_ADDR frame_base = msp430_frame_base (this_frame, this_prologue_cache); |
| 543 | |
| 544 | if (regnum == MSP430_SP_REGNUM) |
| 545 | return frame_unwind_got_constant (this_frame, regnum, frame_base); |
| 546 | |
| 547 | /* If prologue analysis says we saved this register somewhere, |
| 548 | return a description of the stack slot holding it. */ |
| 549 | else if (p->reg_offset[regnum] != 1) |
| 550 | { |
| 551 | struct value *rv = frame_unwind_got_memory (this_frame, regnum, |
| 552 | frame_base + |
| 553 | p->reg_offset[regnum]); |
| 554 | |
| 555 | if (regnum == MSP430_PC_REGNUM) |
| 556 | { |
| 557 | ULONGEST pc = value_as_long (rv); |
| 558 | |
| 559 | return frame_unwind_got_constant (this_frame, regnum, pc); |
| 560 | } |
| 561 | return rv; |
| 562 | } |
| 563 | |
| 564 | /* Otherwise, presume we haven't changed the value of this |
| 565 | register, and get it from the next frame. */ |
| 566 | else |
| 567 | return frame_unwind_got_register (this_frame, regnum, regnum); |
| 568 | } |
| 569 | |
| 570 | static const struct frame_unwind msp430_unwind = { |
| 571 | NORMAL_FRAME, |
| 572 | default_frame_unwind_stop_reason, |
| 573 | msp430_this_id, |
| 574 | msp430_prev_register, |
| 575 | NULL, |
| 576 | default_frame_sniffer |
| 577 | }; |
| 578 | |
| 579 | /* Implement the "dwarf2_reg_to_regnum" gdbarch method. */ |
| 580 | |
| 581 | static int |
| 582 | msp430_dwarf2_reg_to_regnum (struct gdbarch *gdbarch, int reg) |
| 583 | { |
| 584 | if (reg < MSP430_NUM_REGS) |
| 585 | return reg + MSP430_NUM_REGS; |
| 586 | else |
| 587 | { |
| 588 | warning (_("Unmapped DWARF Register #%d encountered."), reg); |
| 589 | return -1; |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | /* Implement the "return_value" gdbarch method. */ |
| 594 | |
| 595 | static enum return_value_convention |
| 596 | msp430_return_value (struct gdbarch *gdbarch, |
| 597 | struct value *function, |
| 598 | struct type *valtype, |
| 599 | struct regcache *regcache, |
| 600 | gdb_byte *readbuf, const gdb_byte *writebuf) |
| 601 | { |
| 602 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 603 | LONGEST valtype_len = TYPE_LENGTH (valtype); |
| 604 | int code_model = gdbarch_tdep (gdbarch)->code_model; |
| 605 | |
| 606 | if (TYPE_LENGTH (valtype) > 8 |
| 607 | || TYPE_CODE (valtype) == TYPE_CODE_STRUCT |
| 608 | || TYPE_CODE (valtype) == TYPE_CODE_UNION) |
| 609 | return RETURN_VALUE_STRUCT_CONVENTION; |
| 610 | |
| 611 | if (readbuf) |
| 612 | { |
| 613 | ULONGEST u; |
| 614 | int argreg = MSP430_R12_REGNUM; |
| 615 | int offset = 0; |
| 616 | |
| 617 | while (valtype_len > 0) |
| 618 | { |
| 619 | int size = 2; |
| 620 | |
| 621 | if (code_model == MSP_LARGE_CODE_MODEL |
| 622 | && TYPE_CODE (valtype) == TYPE_CODE_PTR) |
| 623 | { |
| 624 | size = 4; |
| 625 | } |
| 626 | |
| 627 | regcache_cooked_read_unsigned (regcache, argreg, &u); |
| 628 | store_unsigned_integer (readbuf + offset, size, byte_order, u); |
| 629 | valtype_len -= size; |
| 630 | offset += size; |
| 631 | argreg++; |
| 632 | } |
| 633 | } |
| 634 | |
| 635 | if (writebuf) |
| 636 | { |
| 637 | ULONGEST u; |
| 638 | int argreg = MSP430_R12_REGNUM; |
| 639 | int offset = 0; |
| 640 | |
| 641 | while (valtype_len > 0) |
| 642 | { |
| 643 | int size = 2; |
| 644 | |
| 645 | if (code_model == MSP_LARGE_CODE_MODEL |
| 646 | && TYPE_CODE (valtype) == TYPE_CODE_PTR) |
| 647 | { |
| 648 | size = 4; |
| 649 | } |
| 650 | |
| 651 | u = extract_unsigned_integer (writebuf + offset, size, byte_order); |
| 652 | regcache_cooked_write_unsigned (regcache, argreg, u); |
| 653 | valtype_len -= size; |
| 654 | offset += size; |
| 655 | argreg++; |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 660 | } |
| 661 | |
| 662 | |
| 663 | /* Implement the "frame_align" gdbarch method. */ |
| 664 | |
| 665 | static CORE_ADDR |
| 666 | msp430_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp) |
| 667 | { |
| 668 | return align_down (sp, 2); |
| 669 | } |
| 670 | |
| 671 | |
| 672 | /* Implement the "dummy_id" gdbarch method. */ |
| 673 | |
| 674 | static struct frame_id |
| 675 | msp430_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 676 | { |
| 677 | return |
| 678 | frame_id_build (get_frame_register_unsigned |
| 679 | (this_frame, MSP430_SP_REGNUM), |
| 680 | get_frame_pc (this_frame)); |
| 681 | } |
| 682 | |
| 683 | |
| 684 | /* Implement the "push_dummy_call" gdbarch method. */ |
| 685 | |
| 686 | static CORE_ADDR |
| 687 | msp430_push_dummy_call (struct gdbarch *gdbarch, struct value *function, |
| 688 | struct regcache *regcache, CORE_ADDR bp_addr, |
| 689 | int nargs, struct value **args, CORE_ADDR sp, |
| 690 | int struct_return, CORE_ADDR struct_addr) |
| 691 | { |
| 692 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 693 | int write_pass; |
| 694 | int sp_off = 0; |
| 695 | CORE_ADDR cfa; |
| 696 | int code_model = gdbarch_tdep (gdbarch)->code_model; |
| 697 | |
| 698 | struct type *func_type = value_type (function); |
| 699 | |
| 700 | /* Dereference function pointer types. */ |
| 701 | while (TYPE_CODE (func_type) == TYPE_CODE_PTR) |
| 702 | func_type = TYPE_TARGET_TYPE (func_type); |
| 703 | |
| 704 | /* The end result had better be a function or a method. */ |
| 705 | gdb_assert (TYPE_CODE (func_type) == TYPE_CODE_FUNC |
| 706 | || TYPE_CODE (func_type) == TYPE_CODE_METHOD); |
| 707 | |
| 708 | /* We make two passes; the first does the stack allocation, |
| 709 | the second actually stores the arguments. */ |
| 710 | for (write_pass = 0; write_pass <= 1; write_pass++) |
| 711 | { |
| 712 | int i; |
| 713 | int arg_reg = MSP430_R12_REGNUM; |
| 714 | int args_on_stack = 0; |
| 715 | |
| 716 | if (write_pass) |
| 717 | sp = align_down (sp - sp_off, 4); |
| 718 | sp_off = 0; |
| 719 | |
| 720 | if (struct_return) |
| 721 | { |
| 722 | if (write_pass) |
| 723 | regcache_cooked_write_unsigned (regcache, arg_reg, struct_addr); |
| 724 | arg_reg++; |
| 725 | } |
| 726 | |
| 727 | /* Push the arguments. */ |
| 728 | for (i = 0; i < nargs; i++) |
| 729 | { |
| 730 | struct value *arg = args[i]; |
| 731 | const gdb_byte *arg_bits = value_contents_all (arg); |
| 732 | struct type *arg_type = check_typedef (value_type (arg)); |
| 733 | ULONGEST arg_size = TYPE_LENGTH (arg_type); |
| 734 | int offset; |
| 735 | int current_arg_on_stack; |
| 736 | |
| 737 | current_arg_on_stack = 0; |
| 738 | |
| 739 | if (TYPE_CODE (arg_type) == TYPE_CODE_STRUCT |
| 740 | || TYPE_CODE (arg_type) == TYPE_CODE_UNION) |
| 741 | { |
| 742 | /* Aggregates of any size are passed by reference. */ |
| 743 | gdb_byte struct_addr[4]; |
| 744 | |
| 745 | store_unsigned_integer (struct_addr, 4, byte_order, |
| 746 | value_address (arg)); |
| 747 | arg_bits = struct_addr; |
| 748 | arg_size = (code_model == MSP_LARGE_CODE_MODEL) ? 4 : 2; |
| 749 | } |
| 750 | else |
| 751 | { |
| 752 | /* Scalars bigger than 8 bytes such as complex doubles are passed |
| 753 | on the stack. */ |
| 754 | if (arg_size > 8) |
| 755 | current_arg_on_stack = 1; |
| 756 | } |
| 757 | |
| 758 | |
| 759 | for (offset = 0; offset < arg_size; offset += 2) |
| 760 | { |
| 761 | /* The condition below prevents 8 byte scalars from being split |
| 762 | between registers and memory (stack). It also prevents other |
| 763 | splits once the stack has been written to. */ |
| 764 | if (!current_arg_on_stack |
| 765 | && (arg_reg |
| 766 | + ((arg_size == 8 || args_on_stack) |
| 767 | ? ((arg_size - offset) / 2 - 1) |
| 768 | : 0) <= MSP430_R15_REGNUM)) |
| 769 | { |
| 770 | int size = 2; |
| 771 | |
| 772 | if (code_model == MSP_LARGE_CODE_MODEL |
| 773 | && TYPE_CODE (arg_type) == TYPE_CODE_PTR) |
| 774 | { |
| 775 | /* Pointer arguments using large memory model are passed |
| 776 | using entire register. */ |
| 777 | if (offset != 0) |
| 778 | continue; |
| 779 | size = 4; |
| 780 | } |
| 781 | |
| 782 | if (write_pass) |
| 783 | regcache_cooked_write_unsigned (regcache, arg_reg, |
| 784 | extract_unsigned_integer |
| 785 | (arg_bits + offset, size, |
| 786 | byte_order)); |
| 787 | |
| 788 | arg_reg++; |
| 789 | } |
| 790 | else |
| 791 | { |
| 792 | if (write_pass) |
| 793 | write_memory (sp + sp_off, arg_bits + offset, 2); |
| 794 | |
| 795 | sp_off += 2; |
| 796 | args_on_stack = 1; |
| 797 | current_arg_on_stack = 1; |
| 798 | } |
| 799 | } |
| 800 | } |
| 801 | } |
| 802 | |
| 803 | /* Keep track of the stack address prior to pushing the return address. |
| 804 | This is the value that we'll return. */ |
| 805 | cfa = sp; |
| 806 | |
| 807 | /* Push the return address. */ |
| 808 | { |
| 809 | int sz = (gdbarch_tdep (gdbarch)->code_model == MSP_SMALL_CODE_MODEL) |
| 810 | ? 2 : 4; |
| 811 | sp = sp - sz; |
| 812 | write_memory_unsigned_integer (sp, sz, byte_order, bp_addr); |
| 813 | } |
| 814 | |
| 815 | /* Update the stack pointer. */ |
| 816 | regcache_cooked_write_unsigned (regcache, MSP430_SP_REGNUM, sp); |
| 817 | |
| 818 | return cfa; |
| 819 | } |
| 820 | |
| 821 | /* In order to keep code size small, the compiler may create epilogue |
| 822 | code through which more than one function epilogue is routed. I.e. |
| 823 | the epilogue and return may just be a branch to some common piece of |
| 824 | code which is responsible for tearing down the frame and performing |
| 825 | the return. These epilog (label) names will have the common prefix |
| 826 | defined here. */ |
| 827 | |
| 828 | static const char msp430_epilog_name_prefix[] = "__mspabi_func_epilog_"; |
| 829 | |
| 830 | /* Implement the "in_return_stub" gdbarch method. */ |
| 831 | |
| 832 | static int |
| 833 | msp430_in_return_stub (struct gdbarch *gdbarch, CORE_ADDR pc, |
| 834 | const char *name) |
| 835 | { |
| 836 | return (name != NULL |
| 837 | && startswith (name, msp430_epilog_name_prefix)); |
| 838 | } |
| 839 | |
| 840 | /* Implement the "skip_trampoline_code" gdbarch method. */ |
| 841 | static CORE_ADDR |
| 842 | msp430_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) |
| 843 | { |
| 844 | struct bound_minimal_symbol bms; |
| 845 | const char *stub_name; |
| 846 | struct gdbarch *gdbarch = get_frame_arch (frame); |
| 847 | |
| 848 | bms = lookup_minimal_symbol_by_pc (pc); |
| 849 | if (!bms.minsym) |
| 850 | return pc; |
| 851 | |
| 852 | stub_name = MSYMBOL_LINKAGE_NAME (bms.minsym); |
| 853 | |
| 854 | if (gdbarch_tdep (gdbarch)->code_model == MSP_SMALL_CODE_MODEL |
| 855 | && msp430_in_return_stub (gdbarch, pc, stub_name)) |
| 856 | { |
| 857 | CORE_ADDR sp = get_frame_register_unsigned (frame, MSP430_SP_REGNUM); |
| 858 | |
| 859 | return read_memory_integer |
| 860 | (sp + 2 * (stub_name[strlen (msp430_epilog_name_prefix)] - '0'), |
| 861 | 2, gdbarch_byte_order (gdbarch)); |
| 862 | } |
| 863 | |
| 864 | return pc; |
| 865 | } |
| 866 | |
| 867 | /* Allocate and initialize a gdbarch object. */ |
| 868 | |
| 869 | static struct gdbarch * |
| 870 | msp430_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| 871 | { |
| 872 | struct gdbarch *gdbarch; |
| 873 | struct gdbarch_tdep *tdep; |
| 874 | int elf_flags, isa, code_model; |
| 875 | |
| 876 | /* Extract the elf_flags if available. */ |
| 877 | if (info.abfd != NULL |
| 878 | && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour) |
| 879 | elf_flags = elf_elfheader (info.abfd)->e_flags; |
| 880 | else |
| 881 | elf_flags = 0; |
| 882 | |
| 883 | if (info.abfd != NULL) |
| 884 | switch (bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, |
| 885 | OFBA_MSPABI_Tag_ISA)) |
| 886 | { |
| 887 | case 1: |
| 888 | isa = MSP_ISA_MSP430; |
| 889 | code_model = MSP_SMALL_CODE_MODEL; |
| 890 | break; |
| 891 | case 2: |
| 892 | isa = MSP_ISA_MSP430X; |
| 893 | switch (bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC, |
| 894 | OFBA_MSPABI_Tag_Code_Model)) |
| 895 | { |
| 896 | case 1: |
| 897 | code_model = MSP_SMALL_CODE_MODEL; |
| 898 | break; |
| 899 | case 2: |
| 900 | code_model = MSP_LARGE_CODE_MODEL; |
| 901 | break; |
| 902 | default: |
| 903 | internal_error (__FILE__, __LINE__, |
| 904 | _("Unknown msp430x code memory model")); |
| 905 | break; |
| 906 | } |
| 907 | break; |
| 908 | case 0: |
| 909 | /* This can happen when loading a previously dumped data structure. |
| 910 | Use the ISA and code model from the current architecture, provided |
| 911 | it's compatible. */ |
| 912 | { |
| 913 | struct gdbarch *ca = get_current_arch (); |
| 914 | if (ca && gdbarch_bfd_arch_info (ca)->arch == bfd_arch_msp430) |
| 915 | { |
| 916 | struct gdbarch_tdep *ca_tdep = gdbarch_tdep (ca); |
| 917 | |
| 918 | elf_flags = ca_tdep->elf_flags; |
| 919 | isa = ca_tdep->isa; |
| 920 | code_model = ca_tdep->code_model; |
| 921 | break; |
| 922 | } |
| 923 | /* Otherwise, fall through... */ |
| 924 | } |
| 925 | default: |
| 926 | error (_("Unknown msp430 isa")); |
| 927 | break; |
| 928 | } |
| 929 | else |
| 930 | { |
| 931 | isa = MSP_ISA_MSP430; |
| 932 | code_model = MSP_SMALL_CODE_MODEL; |
| 933 | } |
| 934 | |
| 935 | |
| 936 | /* Try to find the architecture in the list of already defined |
| 937 | architectures. */ |
| 938 | for (arches = gdbarch_list_lookup_by_info (arches, &info); |
| 939 | arches != NULL; |
| 940 | arches = gdbarch_list_lookup_by_info (arches->next, &info)) |
| 941 | { |
| 942 | struct gdbarch_tdep *candidate_tdep = gdbarch_tdep (arches->gdbarch); |
| 943 | |
| 944 | if (candidate_tdep->elf_flags != elf_flags |
| 945 | || candidate_tdep->isa != isa |
| 946 | || candidate_tdep->code_model != code_model) |
| 947 | continue; |
| 948 | |
| 949 | return arches->gdbarch; |
| 950 | } |
| 951 | |
| 952 | /* None found, create a new architecture from the information |
| 953 | provided. */ |
| 954 | tdep = XNEW (struct gdbarch_tdep); |
| 955 | gdbarch = gdbarch_alloc (&info, tdep); |
| 956 | tdep->elf_flags = elf_flags; |
| 957 | tdep->isa = isa; |
| 958 | tdep->code_model = code_model; |
| 959 | |
| 960 | /* Registers. */ |
| 961 | set_gdbarch_num_regs (gdbarch, MSP430_NUM_REGS); |
| 962 | set_gdbarch_num_pseudo_regs (gdbarch, MSP430_NUM_PSEUDO_REGS); |
| 963 | set_gdbarch_register_name (gdbarch, msp430_register_name); |
| 964 | if (isa == MSP_ISA_MSP430) |
| 965 | set_gdbarch_register_type (gdbarch, msp430_register_type); |
| 966 | else |
| 967 | set_gdbarch_register_type (gdbarch, msp430x_register_type); |
| 968 | set_gdbarch_pc_regnum (gdbarch, MSP430_PC_REGNUM); |
| 969 | set_gdbarch_sp_regnum (gdbarch, MSP430_SP_REGNUM); |
| 970 | set_gdbarch_register_reggroup_p (gdbarch, msp430_register_reggroup_p); |
| 971 | set_gdbarch_pseudo_register_read (gdbarch, msp430_pseudo_register_read); |
| 972 | set_gdbarch_pseudo_register_write (gdbarch, msp430_pseudo_register_write); |
| 973 | set_gdbarch_dwarf2_reg_to_regnum (gdbarch, msp430_dwarf2_reg_to_regnum); |
| 974 | set_gdbarch_register_sim_regno (gdbarch, msp430_register_sim_regno); |
| 975 | |
| 976 | /* Data types. */ |
| 977 | set_gdbarch_char_signed (gdbarch, 0); |
| 978 | set_gdbarch_short_bit (gdbarch, 16); |
| 979 | set_gdbarch_int_bit (gdbarch, 16); |
| 980 | set_gdbarch_long_bit (gdbarch, 32); |
| 981 | set_gdbarch_long_long_bit (gdbarch, 64); |
| 982 | if (code_model == MSP_SMALL_CODE_MODEL) |
| 983 | { |
| 984 | set_gdbarch_ptr_bit (gdbarch, 16); |
| 985 | set_gdbarch_addr_bit (gdbarch, 16); |
| 986 | } |
| 987 | else /* MSP_LARGE_CODE_MODEL */ |
| 988 | { |
| 989 | set_gdbarch_ptr_bit (gdbarch, 32); |
| 990 | set_gdbarch_addr_bit (gdbarch, 32); |
| 991 | } |
| 992 | set_gdbarch_dwarf2_addr_size (gdbarch, 4); |
| 993 | set_gdbarch_float_bit (gdbarch, 32); |
| 994 | set_gdbarch_float_format (gdbarch, floatformats_ieee_single); |
| 995 | set_gdbarch_double_bit (gdbarch, 64); |
| 996 | set_gdbarch_long_double_bit (gdbarch, 64); |
| 997 | set_gdbarch_double_format (gdbarch, floatformats_ieee_double); |
| 998 | set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double); |
| 999 | |
| 1000 | /* Breakpoints. */ |
| 1001 | set_gdbarch_breakpoint_from_pc (gdbarch, msp430_breakpoint_from_pc); |
| 1002 | set_gdbarch_decr_pc_after_break (gdbarch, 1); |
| 1003 | |
| 1004 | /* Disassembly. */ |
| 1005 | set_gdbarch_print_insn (gdbarch, print_insn_msp430); |
| 1006 | |
| 1007 | /* Frames, prologues, etc. */ |
| 1008 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 1009 | set_gdbarch_skip_prologue (gdbarch, msp430_skip_prologue); |
| 1010 | set_gdbarch_unwind_pc (gdbarch, msp430_unwind_pc); |
| 1011 | set_gdbarch_unwind_sp (gdbarch, msp430_unwind_sp); |
| 1012 | set_gdbarch_frame_align (gdbarch, msp430_frame_align); |
| 1013 | dwarf2_append_unwinders (gdbarch); |
| 1014 | frame_unwind_append_unwinder (gdbarch, &msp430_unwind); |
| 1015 | |
| 1016 | /* Dummy frames, return values. */ |
| 1017 | set_gdbarch_dummy_id (gdbarch, msp430_dummy_id); |
| 1018 | set_gdbarch_push_dummy_call (gdbarch, msp430_push_dummy_call); |
| 1019 | set_gdbarch_return_value (gdbarch, msp430_return_value); |
| 1020 | |
| 1021 | /* Trampolines. */ |
| 1022 | set_gdbarch_in_solib_return_trampoline (gdbarch, msp430_in_return_stub); |
| 1023 | set_gdbarch_skip_trampoline_code (gdbarch, msp430_skip_trampoline_code); |
| 1024 | |
| 1025 | /* Virtual tables. */ |
| 1026 | set_gdbarch_vbit_in_delta (gdbarch, 0); |
| 1027 | |
| 1028 | return gdbarch; |
| 1029 | } |
| 1030 | |
| 1031 | /* -Wmissing-prototypes */ |
| 1032 | extern initialize_file_ftype _initialize_msp430_tdep; |
| 1033 | |
| 1034 | /* Register the initialization routine. */ |
| 1035 | |
| 1036 | void |
| 1037 | _initialize_msp430_tdep (void) |
| 1038 | { |
| 1039 | register_gdbarch_init (bfd_arch_msp430, msp430_gdbarch_init); |
| 1040 | } |