| 1 | /* Target-dependent code for Analog Devices Blackfin processor, for GDB. |
| 2 | |
| 3 | Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 |
| 4 | Free Software Foundation, Inc. |
| 5 | |
| 6 | Contributed by Analog Devices, 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 "gdb_string.h" |
| 25 | #include "inferior.h" |
| 26 | #include "gdbcore.h" |
| 27 | #include "arch-utils.h" |
| 28 | #include "regcache.h" |
| 29 | #include "frame.h" |
| 30 | #include "frame-unwind.h" |
| 31 | #include "frame-base.h" |
| 32 | #include "trad-frame.h" |
| 33 | #include "dis-asm.h" |
| 34 | #include "gdb_assert.h" |
| 35 | #include "sim-regno.h" |
| 36 | #include "gdb/sim-bfin.h" |
| 37 | #include "dwarf2-frame.h" |
| 38 | #include "symtab.h" |
| 39 | #include "elf-bfd.h" |
| 40 | #include "elf/bfin.h" |
| 41 | #include "osabi.h" |
| 42 | #include "infcall.h" |
| 43 | #include "xml-syscall.h" |
| 44 | #include "bfin-tdep.h" |
| 45 | |
| 46 | /* Macros used by prologue functions. */ |
| 47 | #define P_LINKAGE 0xE800 |
| 48 | #define P_MINUS_SP1 0x0140 |
| 49 | #define P_MINUS_SP2 0x05C0 |
| 50 | #define P_MINUS_SP3 0x0540 |
| 51 | #define P_MINUS_SP4 0x04C0 |
| 52 | #define P_SP_PLUS 0x6C06 |
| 53 | #define P_P2_LOW 0xE10A |
| 54 | #define P_P2_HIGH 0XE14A |
| 55 | #define P_SP_EQ_SP_PLUS_P2 0X5BB2 |
| 56 | #define P_SP_EQ_P2_PLUS_SP 0x5B96 |
| 57 | #define P_MINUS_MINUS_SP_EQ_RETS 0x0167 |
| 58 | |
| 59 | /* Macros used for program flow control. */ |
| 60 | /* 16 bit instruction, max */ |
| 61 | #define P_16_BIT_INSR_MAX 0xBFFF |
| 62 | /* 32 bit instruction, min */ |
| 63 | #define P_32_BIT_INSR_MIN 0xC000 |
| 64 | /* 32 bit instruction, max */ |
| 65 | #define P_32_BIT_INSR_MAX 0xE801 |
| 66 | /* jump (preg), 16-bit, min */ |
| 67 | #define P_JUMP_PREG_MIN 0x0050 |
| 68 | /* jump (preg), 16-bit, max */ |
| 69 | #define P_JUMP_PREG_MAX 0x0057 |
| 70 | /* jump (pc+preg), 16-bit, min */ |
| 71 | #define P_JUMP_PC_PLUS_PREG_MIN 0x0080 |
| 72 | /* jump (pc+preg), 16-bit, max */ |
| 73 | #define P_JUMP_PC_PLUS_PREG_MAX 0x0087 |
| 74 | /* jump.s pcrel13m2, 16-bit, min */ |
| 75 | #define P_JUMP_S_MIN 0x2000 |
| 76 | /* jump.s pcrel13m2, 16-bit, max */ |
| 77 | #define P_JUMP_S_MAX 0x2FFF |
| 78 | /* jump.l pcrel25m2, 32-bit, min */ |
| 79 | #define P_JUMP_L_MIN 0xE200 |
| 80 | /* jump.l pcrel25m2, 32-bit, max */ |
| 81 | #define P_JUMP_L_MAX 0xE2FF |
| 82 | /* conditional jump pcrel11m2, 16-bit, min */ |
| 83 | #define P_IF_CC_JUMP_MIN 0x1800 |
| 84 | /* conditional jump pcrel11m2, 16-bit, max */ |
| 85 | #define P_IF_CC_JUMP_MAX 0x1BFF |
| 86 | /* conditional jump(bp) pcrel11m2, 16-bit, min */ |
| 87 | #define P_IF_CC_JUMP_BP_MIN 0x1C00 |
| 88 | /* conditional jump(bp) pcrel11m2, 16-bit, max */ |
| 89 | #define P_IF_CC_JUMP_BP_MAX 0x1FFF |
| 90 | /* conditional !jump pcrel11m2, 16-bit, min */ |
| 91 | #define P_IF_NOT_CC_JUMP_MIN 0x1000 |
| 92 | /* conditional !jump pcrel11m2, 16-bit, max */ |
| 93 | #define P_IF_NOT_CC_JUMP_MAX 0x13FF |
| 94 | /* conditional jump(bp) pcrel11m2, 16-bit, min */ |
| 95 | #define P_IF_NOT_CC_JUMP_BP_MIN 0x1400 |
| 96 | /* conditional jump(bp) pcrel11m2, 16-bit, max */ |
| 97 | #define P_IF_NOT_CC_JUMP_BP_MAX 0x17FF |
| 98 | /* call (preg), 16-bit, min */ |
| 99 | #define P_CALL_PREG_MIN 0x0060 |
| 100 | /* call (preg), 16-bit, max */ |
| 101 | #define P_CALL_PREG_MAX 0x0067 |
| 102 | /* call (pc+preg), 16-bit, min */ |
| 103 | #define P_CALL_PC_PLUS_PREG_MIN 0x0070 |
| 104 | /* call (pc+preg), 16-bit, max */ |
| 105 | #define P_CALL_PC_PLUS_PREG_MAX 0x0077 |
| 106 | /* call pcrel25m2, 32-bit, min */ |
| 107 | #define P_CALL_MIN 0xE300 |
| 108 | /* call pcrel25m2, 32-bit, max */ |
| 109 | #define P_CALL_MAX 0xE3FF |
| 110 | /* RTS */ |
| 111 | #define P_RTS 0x0010 |
| 112 | /* MNOP */ |
| 113 | #define P_MNOP 0xC803 |
| 114 | /* EXCPT, 16-bit, min */ |
| 115 | #define P_EXCPT_MIN 0x00A0 |
| 116 | /* EXCPT, 16-bit, max */ |
| 117 | #define P_EXCPT_MAX 0x00AF |
| 118 | /* multi instruction mask 1, 16-bit */ |
| 119 | #define P_BIT_MULTI_INS_1 0xC000 |
| 120 | /* multi instruction mask 2, 16-bit */ |
| 121 | #define P_BIT_MULTI_INS_2 0x0800 |
| 122 | |
| 123 | /* The maximum bytes we search to skip the prologue. */ |
| 124 | #define UPPER_LIMIT 40 |
| 125 | |
| 126 | /* ASTAT bits */ |
| 127 | #define ASTAT_CC_POS 5 |
| 128 | #define ASTAT_CC (1 << ASTAT_CC_POS) |
| 129 | |
| 130 | /* Initial value: Register names used in BFIN's ISA documentation. */ |
| 131 | |
| 132 | static const char * const bfin_register_name_strings[] = |
| 133 | { |
| 134 | "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", |
| 135 | "p0", "p1", "p2", "p3", "p4", "p5", "sp", "fp", |
| 136 | "i0", "i1", "i2", "i3", "m0", "m1", "m2", "m3", |
| 137 | "b0", "b1", "b2", "b3", "l0", "l1", "l2", "l3", |
| 138 | "a0x", "a0w", "a1x", "a1w", "astat", "rets", |
| 139 | "lc0", "lt0", "lb0", "lc1", "lt1", "lb1", "cycles", "cycles2", |
| 140 | "usp", "seqstat", "syscfg", "reti", "retx", "retn", "rete", |
| 141 | "pc", "cc", |
| 142 | }; |
| 143 | |
| 144 | #define NUM_BFIN_REGNAMES ARRAY_SIZE (bfin_register_name_strings) |
| 145 | |
| 146 | |
| 147 | /* In this diagram successive memory locations increase downwards or the |
| 148 | stack grows upwards with negative indices. (PUSH analogy for stack.) |
| 149 | |
| 150 | The top frame is the "frame" of the current function being executed. |
| 151 | |
| 152 | +--------------+ SP - |
| 153 | | local vars | ^ |
| 154 | +--------------+ | |
| 155 | | save regs | | |
| 156 | +--------------+ FP | |
| 157 | | old FP -|-- top |
| 158 | +--------------+ | frame |
| 159 | | RETS | | | |
| 160 | +--------------+ | | |
| 161 | | param 1 | | | |
| 162 | | param 2 | | | |
| 163 | | ... | | V |
| 164 | +--------------+ | - |
| 165 | | local vars | | ^ |
| 166 | +--------------+ | | |
| 167 | | save regs | | | |
| 168 | +--------------+<- | |
| 169 | | old FP -|-- next |
| 170 | +--------------+ | frame |
| 171 | | RETS | | | |
| 172 | +--------------+ | | |
| 173 | | param 1 | | | |
| 174 | | param 2 | | | |
| 175 | | ... | | V |
| 176 | +--------------+ | - |
| 177 | | local vars | | ^ |
| 178 | +--------------+ | | |
| 179 | | save regs | | | |
| 180 | +--------------+<- next frame |
| 181 | | old FP | | |
| 182 | +--------------+ | |
| 183 | | RETS | V |
| 184 | +--------------+ - |
| 185 | |
| 186 | The frame chain is formed as following: |
| 187 | |
| 188 | FP has the topmost frame. |
| 189 | FP + 4 has the previous FP and so on. */ |
| 190 | |
| 191 | |
| 192 | /* Map from DWARF2 register number to GDB register number. */ |
| 193 | |
| 194 | static const int map_gcc_gdb[] = |
| 195 | { |
| 196 | BFIN_R0_REGNUM, |
| 197 | BFIN_R1_REGNUM, |
| 198 | BFIN_R2_REGNUM, |
| 199 | BFIN_R3_REGNUM, |
| 200 | BFIN_R4_REGNUM, |
| 201 | BFIN_R5_REGNUM, |
| 202 | BFIN_R6_REGNUM, |
| 203 | BFIN_R7_REGNUM, |
| 204 | BFIN_P0_REGNUM, |
| 205 | BFIN_P1_REGNUM, |
| 206 | BFIN_P2_REGNUM, |
| 207 | BFIN_P3_REGNUM, |
| 208 | BFIN_P4_REGNUM, |
| 209 | BFIN_P5_REGNUM, |
| 210 | BFIN_SP_REGNUM, |
| 211 | BFIN_FP_REGNUM, |
| 212 | BFIN_I0_REGNUM, |
| 213 | BFIN_I1_REGNUM, |
| 214 | BFIN_I2_REGNUM, |
| 215 | BFIN_I3_REGNUM, |
| 216 | BFIN_B0_REGNUM, |
| 217 | BFIN_B1_REGNUM, |
| 218 | BFIN_B2_REGNUM, |
| 219 | BFIN_B3_REGNUM, |
| 220 | BFIN_L0_REGNUM, |
| 221 | BFIN_L1_REGNUM, |
| 222 | BFIN_L2_REGNUM, |
| 223 | BFIN_L3_REGNUM, |
| 224 | BFIN_M0_REGNUM, |
| 225 | BFIN_M1_REGNUM, |
| 226 | BFIN_M2_REGNUM, |
| 227 | BFIN_M3_REGNUM, |
| 228 | BFIN_A0_DOT_X_REGNUM, |
| 229 | BFIN_A1_DOT_X_REGNUM, |
| 230 | BFIN_CC_REGNUM, |
| 231 | BFIN_RETS_REGNUM, |
| 232 | BFIN_RETI_REGNUM, |
| 233 | BFIN_RETX_REGNUM, |
| 234 | BFIN_RETN_REGNUM, |
| 235 | BFIN_RETE_REGNUM, |
| 236 | BFIN_ASTAT_REGNUM, |
| 237 | BFIN_SEQSTAT_REGNUM, |
| 238 | BFIN_USP_REGNUM, |
| 239 | BFIN_LT0_REGNUM, |
| 240 | BFIN_LT1_REGNUM, |
| 241 | BFIN_LC0_REGNUM, |
| 242 | BFIN_LC1_REGNUM, |
| 243 | BFIN_LB0_REGNUM, |
| 244 | BFIN_LB1_REGNUM |
| 245 | }; |
| 246 | |
| 247 | |
| 248 | struct bfin_frame_cache |
| 249 | { |
| 250 | /* Base address. */ |
| 251 | CORE_ADDR base; |
| 252 | CORE_ADDR sp_offset; |
| 253 | CORE_ADDR pc; |
| 254 | int frameless_pc_value; |
| 255 | |
| 256 | /* Saved registers. */ |
| 257 | CORE_ADDR saved_regs[BFIN_NUM_REGS]; |
| 258 | CORE_ADDR saved_sp; |
| 259 | |
| 260 | /* Stack space reserved for local variables. */ |
| 261 | long locals; |
| 262 | }; |
| 263 | |
| 264 | /* Allocate and initialize a frame cache. */ |
| 265 | |
| 266 | static struct bfin_frame_cache * |
| 267 | bfin_alloc_frame_cache (void) |
| 268 | { |
| 269 | struct bfin_frame_cache *cache; |
| 270 | int i; |
| 271 | |
| 272 | cache = FRAME_OBSTACK_ZALLOC (struct bfin_frame_cache); |
| 273 | |
| 274 | /* Base address. */ |
| 275 | cache->base = 0; |
| 276 | cache->sp_offset = -4; |
| 277 | cache->pc = 0; |
| 278 | cache->frameless_pc_value = 0; |
| 279 | |
| 280 | /* Saved registers. We initialize these to -1 since zero is a valid |
| 281 | offset (that's where fp is supposed to be stored). */ |
| 282 | for (i = 0; i < BFIN_NUM_REGS; i++) |
| 283 | cache->saved_regs[i] = -1; |
| 284 | |
| 285 | /* Frameless until proven otherwise. */ |
| 286 | cache->locals = -1; |
| 287 | |
| 288 | return cache; |
| 289 | } |
| 290 | |
| 291 | static struct bfin_frame_cache * |
| 292 | bfin_frame_cache (struct frame_info *this_frame, void **this_cache) |
| 293 | { |
| 294 | struct bfin_frame_cache *cache; |
| 295 | int i; |
| 296 | |
| 297 | if (*this_cache) |
| 298 | return *this_cache; |
| 299 | |
| 300 | cache = bfin_alloc_frame_cache (); |
| 301 | *this_cache = cache; |
| 302 | |
| 303 | cache->base = get_frame_register_unsigned (this_frame, BFIN_FP_REGNUM); |
| 304 | if (cache->base == 0) |
| 305 | return cache; |
| 306 | |
| 307 | /* For normal frames, PC is stored at [FP + 4]. */ |
| 308 | cache->saved_regs[BFIN_PC_REGNUM] = 4; |
| 309 | cache->saved_regs[BFIN_FP_REGNUM] = 0; |
| 310 | |
| 311 | /* Adjust all the saved registers such that they contain addresses |
| 312 | instead of offsets. */ |
| 313 | for (i = 0; i < BFIN_NUM_REGS; i++) |
| 314 | if (cache->saved_regs[i] != -1) |
| 315 | cache->saved_regs[i] += cache->base; |
| 316 | |
| 317 | cache->pc = get_frame_func (this_frame) ; |
| 318 | if (cache->pc == 0 || cache->pc == get_frame_pc (this_frame)) |
| 319 | { |
| 320 | /* Either there is no prologue (frameless function) or we are at |
| 321 | the start of a function. In short we do not have a frame. |
| 322 | PC is stored in rets register. FP points to previous frame. */ |
| 323 | |
| 324 | cache->saved_regs[BFIN_PC_REGNUM] = |
| 325 | get_frame_register_unsigned (this_frame, BFIN_RETS_REGNUM); |
| 326 | cache->frameless_pc_value = 1; |
| 327 | cache->base = get_frame_register_unsigned (this_frame, BFIN_FP_REGNUM); |
| 328 | cache->saved_regs[BFIN_FP_REGNUM] = cache->base; |
| 329 | cache->saved_sp = cache->base; |
| 330 | } |
| 331 | else |
| 332 | { |
| 333 | cache->frameless_pc_value = 0; |
| 334 | |
| 335 | /* Now that we have the base address for the stack frame we can |
| 336 | calculate the value of SP in the calling frame. */ |
| 337 | cache->saved_sp = cache->base + 8; |
| 338 | } |
| 339 | |
| 340 | return cache; |
| 341 | } |
| 342 | |
| 343 | static void |
| 344 | bfin_frame_this_id (struct frame_info *this_frame, |
| 345 | void **this_cache, |
| 346 | struct frame_id *this_id) |
| 347 | { |
| 348 | struct bfin_frame_cache *cache = bfin_frame_cache (this_frame, this_cache); |
| 349 | |
| 350 | /* This marks the outermost frame. */ |
| 351 | if (cache->base == 0) |
| 352 | return; |
| 353 | |
| 354 | /* See the end of bfin_push_dummy_call. */ |
| 355 | *this_id = frame_id_build (cache->base + 8, cache->pc); |
| 356 | } |
| 357 | |
| 358 | static struct value * |
| 359 | bfin_frame_prev_register (struct frame_info *this_frame, |
| 360 | void **this_cache, |
| 361 | int regnum) |
| 362 | { |
| 363 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 364 | struct bfin_frame_cache *cache = bfin_frame_cache (this_frame, this_cache); |
| 365 | |
| 366 | if (regnum == gdbarch_sp_regnum (gdbarch) && cache->saved_sp) |
| 367 | return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp); |
| 368 | |
| 369 | if (regnum < BFIN_NUM_REGS && cache->saved_regs[regnum] != -1) |
| 370 | return frame_unwind_got_memory (this_frame, regnum, |
| 371 | cache->saved_regs[regnum]); |
| 372 | |
| 373 | return frame_unwind_got_register (this_frame, regnum, regnum); |
| 374 | } |
| 375 | |
| 376 | static const struct frame_unwind bfin_frame_unwind = |
| 377 | { |
| 378 | NORMAL_FRAME, |
| 379 | default_frame_unwind_stop_reason, |
| 380 | bfin_frame_this_id, |
| 381 | bfin_frame_prev_register, |
| 382 | NULL, |
| 383 | default_frame_sniffer |
| 384 | }; |
| 385 | |
| 386 | /* Check for "[--SP] = <reg>;" insns. These are appear in function |
| 387 | prologues to save misc registers onto the stack. */ |
| 388 | |
| 389 | static int |
| 390 | is_minus_minus_sp (int op) |
| 391 | { |
| 392 | op &= 0xFFC0; |
| 393 | |
| 394 | if ((op == P_MINUS_SP1) || (op == P_MINUS_SP2) |
| 395 | || (op == P_MINUS_SP3) || (op == P_MINUS_SP4)) |
| 396 | return 1; |
| 397 | |
| 398 | return 0; |
| 399 | } |
| 400 | |
| 401 | /* Skip all the insns that appear in generated function prologues. */ |
| 402 | |
| 403 | static CORE_ADDR |
| 404 | bfin_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 405 | { |
| 406 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 407 | int op = read_memory_unsigned_integer (pc, 2, byte_order); |
| 408 | CORE_ADDR orig_pc = pc; |
| 409 | int done = 0; |
| 410 | |
| 411 | /* The new gcc prologue generates the register saves BEFORE the link |
| 412 | or RETS saving instruction. |
| 413 | So, our job is to stop either at those instructions or some upper |
| 414 | limit saying there is no frame! */ |
| 415 | |
| 416 | while (!done) |
| 417 | { |
| 418 | if (is_minus_minus_sp (op)) |
| 419 | { |
| 420 | while (is_minus_minus_sp (op)) |
| 421 | { |
| 422 | pc += 2; |
| 423 | op = read_memory_unsigned_integer (pc, 2, byte_order); |
| 424 | } |
| 425 | |
| 426 | if (op == P_LINKAGE) |
| 427 | pc += 4; |
| 428 | |
| 429 | done = 1; |
| 430 | } |
| 431 | else if (op == P_LINKAGE) |
| 432 | { |
| 433 | pc += 4; |
| 434 | done = 1; |
| 435 | } |
| 436 | else if (op == P_MINUS_MINUS_SP_EQ_RETS) |
| 437 | { |
| 438 | pc += 2; |
| 439 | done = 1; |
| 440 | } |
| 441 | else if (op == P_RTS) |
| 442 | { |
| 443 | done = 1; |
| 444 | } |
| 445 | else if ((op >= P_JUMP_PREG_MIN && op <= P_JUMP_PREG_MAX) |
| 446 | || (op >= P_JUMP_PC_PLUS_PREG_MIN |
| 447 | && op <= P_JUMP_PC_PLUS_PREG_MAX) |
| 448 | || (op == P_JUMP_S_MIN && op <= P_JUMP_S_MAX)) |
| 449 | { |
| 450 | done = 1; |
| 451 | } |
| 452 | else if (pc - orig_pc >= UPPER_LIMIT) |
| 453 | { |
| 454 | warning (_("Function Prologue not recognised; " |
| 455 | "pc will point to ENTRY_POINT of the function")); |
| 456 | pc = orig_pc + 2; |
| 457 | done = 1; |
| 458 | } |
| 459 | else |
| 460 | { |
| 461 | pc += 2; /* Not a terminating instruction go on. */ |
| 462 | op = read_memory_unsigned_integer (pc, 2, byte_order); |
| 463 | } |
| 464 | } |
| 465 | |
| 466 | /* TODO: |
| 467 | Dwarf2 uses entry point value AFTER some register initializations. |
| 468 | We should perhaps skip such asssignments as well (R6 = R1, ...). */ |
| 469 | |
| 470 | return pc; |
| 471 | } |
| 472 | |
| 473 | /* Return the GDB type object for the "standard" data type of data in |
| 474 | register N. This should be void pointer for P0-P5, SP, FP; |
| 475 | void pointer to function for PC; int otherwise. */ |
| 476 | |
| 477 | static struct type * |
| 478 | bfin_register_type (struct gdbarch *gdbarch, int regnum) |
| 479 | { |
| 480 | if ((regnum >= BFIN_P0_REGNUM && regnum <= BFIN_FP_REGNUM) |
| 481 | || regnum == BFIN_USP_REGNUM) |
| 482 | return builtin_type (gdbarch)->builtin_data_ptr; |
| 483 | |
| 484 | if (regnum == BFIN_PC_REGNUM || regnum == BFIN_RETS_REGNUM |
| 485 | || regnum == BFIN_RETI_REGNUM || regnum == BFIN_RETX_REGNUM |
| 486 | || regnum == BFIN_RETN_REGNUM || regnum == BFIN_RETE_REGNUM |
| 487 | || regnum == BFIN_LT0_REGNUM || regnum == BFIN_LB0_REGNUM |
| 488 | || regnum == BFIN_LT1_REGNUM || regnum == BFIN_LB1_REGNUM) |
| 489 | return builtin_type (gdbarch)->builtin_func_ptr; |
| 490 | |
| 491 | return builtin_type (gdbarch)->builtin_int32; |
| 492 | } |
| 493 | |
| 494 | static CORE_ADDR |
| 495 | bfin_push_dummy_call (struct gdbarch *gdbarch, |
| 496 | struct value *function, |
| 497 | struct regcache *regcache, |
| 498 | CORE_ADDR bp_addr, |
| 499 | int nargs, |
| 500 | struct value **args, |
| 501 | CORE_ADDR sp, |
| 502 | int struct_return, |
| 503 | CORE_ADDR struct_addr) |
| 504 | { |
| 505 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 506 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 507 | char buf[4]; |
| 508 | int i; |
| 509 | long reg_r0, reg_r1, reg_r2; |
| 510 | int total_len = 0; |
| 511 | enum bfin_abi abi = bfin_abi (gdbarch); |
| 512 | CORE_ADDR func_addr = find_function_addr (function, NULL); |
| 513 | |
| 514 | for (i = nargs - 1; i >= 0; i--) |
| 515 | { |
| 516 | struct type *value_type = value_enclosing_type (args[i]); |
| 517 | int len = TYPE_LENGTH (value_type); |
| 518 | |
| 519 | total_len += (len + 3) & ~3; |
| 520 | } |
| 521 | |
| 522 | /* At least twelve bytes of stack space must be allocated for the function's |
| 523 | arguments, even for functions that have less than 12 bytes of argument |
| 524 | data. */ |
| 525 | |
| 526 | if (total_len < 12) |
| 527 | sp -= 12 - total_len; |
| 528 | |
| 529 | /* Push arguments in reverse order. */ |
| 530 | |
| 531 | for (i = nargs - 1; i >= 0; i--) |
| 532 | { |
| 533 | struct type *value_type = value_enclosing_type (args[i]); |
| 534 | struct type *arg_type = check_typedef (value_type); |
| 535 | int len = TYPE_LENGTH (value_type); |
| 536 | int container_len = (len + 3) & ~3; |
| 537 | |
| 538 | sp -= container_len; |
| 539 | write_memory (sp, value_contents_writeable (args[i]), container_len); |
| 540 | } |
| 541 | |
| 542 | /* Initialize R0, R1, and R2 to the first 3 words of parameters. */ |
| 543 | |
| 544 | reg_r0 = read_memory_integer (sp, 4, byte_order); |
| 545 | regcache_cooked_write_unsigned (regcache, BFIN_R0_REGNUM, reg_r0); |
| 546 | reg_r1 = read_memory_integer (sp + 4, 4, byte_order); |
| 547 | regcache_cooked_write_unsigned (regcache, BFIN_R1_REGNUM, reg_r1); |
| 548 | reg_r2 = read_memory_integer (sp + 8, 4, byte_order); |
| 549 | regcache_cooked_write_unsigned (regcache, BFIN_R2_REGNUM, reg_r2); |
| 550 | |
| 551 | /* Store struct value address. */ |
| 552 | |
| 553 | if (struct_return) |
| 554 | regcache_cooked_write_unsigned (regcache, BFIN_P0_REGNUM, struct_addr); |
| 555 | |
| 556 | /* Set the dummy return value to bp_addr. |
| 557 | A dummy breakpoint will be setup to execute the call. */ |
| 558 | |
| 559 | regcache_cooked_write_unsigned (regcache, BFIN_RETS_REGNUM, bp_addr); |
| 560 | |
| 561 | /* Finally, update the stack pointer. */ |
| 562 | |
| 563 | regcache_cooked_write_unsigned (regcache, BFIN_SP_REGNUM, sp); |
| 564 | |
| 565 | return sp; |
| 566 | } |
| 567 | |
| 568 | /* Convert DWARF2 register number REG to the appropriate register number |
| 569 | used by GDB. */ |
| 570 | |
| 571 | static int |
| 572 | bfin_reg_to_regnum (struct gdbarch *gdbarch, int reg) |
| 573 | { |
| 574 | if (reg > ARRAY_SIZE (map_gcc_gdb)) |
| 575 | return 0; |
| 576 | |
| 577 | return map_gcc_gdb[reg]; |
| 578 | } |
| 579 | |
| 580 | /* This function implements the BREAKPOINT_FROM_PC macro. It returns |
| 581 | a pointer to a string of bytes that encode a breakpoint instruction, |
| 582 | stores the length of the string to *lenptr, and adjusts the program |
| 583 | counter (if necessary) to point to the actual memory location where |
| 584 | the breakpoint should be inserted. */ |
| 585 | |
| 586 | static const unsigned char * |
| 587 | bfin_breakpoint_from_pc (struct gdbarch *gdbarch, |
| 588 | CORE_ADDR *pcptr, int *lenptr) |
| 589 | { |
| 590 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 591 | unsigned short iw; |
| 592 | static unsigned char bfin_breakpoint[] = {0xa1, 0x00, 0x00, 0x00}; |
| 593 | static unsigned char bfin_sim_breakpoint[] = {0x25, 0x00, 0x00, 0x00}; |
| 594 | |
| 595 | iw = read_memory_unsigned_integer (*pcptr, 2, byte_order); |
| 596 | |
| 597 | if ((iw & 0xf000) >= 0xc000) |
| 598 | /* 32-bit instruction. */ |
| 599 | *lenptr = 4; |
| 600 | else |
| 601 | *lenptr = 2; |
| 602 | |
| 603 | if (strcmp (target_shortname, "sim") == 0) |
| 604 | return bfin_sim_breakpoint; |
| 605 | else |
| 606 | return bfin_breakpoint; |
| 607 | } |
| 608 | |
| 609 | static void |
| 610 | bfin_extract_return_value (struct type *type, |
| 611 | struct regcache *regs, |
| 612 | gdb_byte *dst) |
| 613 | { |
| 614 | struct gdbarch *gdbarch = get_regcache_arch (regs); |
| 615 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 616 | bfd_byte *valbuf = dst; |
| 617 | int len = TYPE_LENGTH (type); |
| 618 | ULONGEST tmp; |
| 619 | int regno = BFIN_R0_REGNUM; |
| 620 | |
| 621 | gdb_assert (len <= 8); |
| 622 | |
| 623 | while (len > 0) |
| 624 | { |
| 625 | regcache_cooked_read_unsigned (regs, regno++, &tmp); |
| 626 | store_unsigned_integer (valbuf, (len > 4 ? 4 : len), tmp, byte_order); |
| 627 | len -= 4; |
| 628 | valbuf += 4; |
| 629 | } |
| 630 | } |
| 631 | |
| 632 | /* Write into appropriate registers a function return value of type |
| 633 | TYPE, given in virtual format. */ |
| 634 | |
| 635 | static void |
| 636 | bfin_store_return_value (struct type *type, |
| 637 | struct regcache *regs, |
| 638 | const gdb_byte *src) |
| 639 | { |
| 640 | const bfd_byte *valbuf = src; |
| 641 | |
| 642 | /* Integral values greater than one word are stored in consecutive |
| 643 | registers starting with R0. This will always be a multiple of |
| 644 | the register size. */ |
| 645 | |
| 646 | int len = TYPE_LENGTH (type); |
| 647 | int regno = BFIN_R0_REGNUM; |
| 648 | |
| 649 | gdb_assert (len <= 8); |
| 650 | |
| 651 | while (len > 0) |
| 652 | { |
| 653 | regcache_cooked_write (regs, regno++, valbuf); |
| 654 | len -= 4; |
| 655 | valbuf += 4; |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | /* Determine, for architecture GDBARCH, how a return value of TYPE |
| 660 | should be returned. If it is supposed to be returned in registers, |
| 661 | and READBUF is nonzero, read the appropriate value from REGCACHE, |
| 662 | and copy it into READBUF. If WRITEBUF is nonzero, write the value |
| 663 | from WRITEBUF into REGCACHE. */ |
| 664 | |
| 665 | static enum return_value_convention |
| 666 | bfin_return_value (struct gdbarch *gdbarch, |
| 667 | struct type *func_type, |
| 668 | struct type *type, |
| 669 | struct regcache *regcache, |
| 670 | gdb_byte *readbuf, |
| 671 | const gdb_byte *writebuf) |
| 672 | { |
| 673 | if (TYPE_LENGTH (type) > 8) |
| 674 | return RETURN_VALUE_STRUCT_CONVENTION; |
| 675 | |
| 676 | if (readbuf) |
| 677 | bfin_extract_return_value (type, regcache, readbuf); |
| 678 | |
| 679 | if (writebuf) |
| 680 | bfin_store_return_value (type, regcache, writebuf); |
| 681 | |
| 682 | return RETURN_VALUE_REGISTER_CONVENTION; |
| 683 | } |
| 684 | |
| 685 | /* Return the BFIN register name corresponding to register I. */ |
| 686 | |
| 687 | static const char * |
| 688 | bfin_register_name (struct gdbarch *gdbarch, int i) |
| 689 | { |
| 690 | return bfin_register_name_strings[i]; |
| 691 | } |
| 692 | |
| 693 | static enum register_status |
| 694 | bfin_pseudo_register_read (struct gdbarch *gdbarch, struct regcache *regcache, |
| 695 | int regnum, gdb_byte *buffer) |
| 696 | { |
| 697 | gdb_byte *buf = (gdb_byte *) alloca (MAX_REGISTER_SIZE); |
| 698 | enum register_status status; |
| 699 | |
| 700 | if (regnum != BFIN_CC_REGNUM) |
| 701 | internal_error (__FILE__, __LINE__, |
| 702 | _("invalid register number %d"), regnum); |
| 703 | |
| 704 | /* Extract the CC bit from the ASTAT register. */ |
| 705 | status = regcache_raw_read (regcache, BFIN_ASTAT_REGNUM, buf); |
| 706 | if (status == REG_VALID) |
| 707 | { |
| 708 | buffer[1] = buffer[2] = buffer[3] = 0; |
| 709 | buffer[0] = !!(buf[0] & ASTAT_CC); |
| 710 | } |
| 711 | return status; |
| 712 | } |
| 713 | |
| 714 | static void |
| 715 | bfin_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache, |
| 716 | int regnum, const gdb_byte *buffer) |
| 717 | { |
| 718 | gdb_byte *buf = (gdb_byte *) alloca (MAX_REGISTER_SIZE); |
| 719 | |
| 720 | if (regnum != BFIN_CC_REGNUM) |
| 721 | internal_error (__FILE__, __LINE__, |
| 722 | _("invalid register number %d"), regnum); |
| 723 | |
| 724 | /* Overlay the CC bit in the ASTAT register. */ |
| 725 | regcache_raw_read (regcache, BFIN_ASTAT_REGNUM, buf); |
| 726 | buf[0] = (buf[0] & ~ASTAT_CC) | ((buffer[0] & 1) << ASTAT_CC_POS); |
| 727 | regcache_raw_write (regcache, BFIN_ASTAT_REGNUM, buf); |
| 728 | } |
| 729 | |
| 730 | static CORE_ADDR |
| 731 | bfin_frame_base_address (struct frame_info *this_frame, void **this_cache) |
| 732 | { |
| 733 | struct bfin_frame_cache *cache = bfin_frame_cache (this_frame, this_cache); |
| 734 | |
| 735 | return cache->base; |
| 736 | } |
| 737 | |
| 738 | static CORE_ADDR |
| 739 | bfin_frame_local_address (struct frame_info *this_frame, void **this_cache) |
| 740 | { |
| 741 | struct bfin_frame_cache *cache = bfin_frame_cache (this_frame, this_cache); |
| 742 | |
| 743 | return cache->base - 4; |
| 744 | } |
| 745 | |
| 746 | static CORE_ADDR |
| 747 | bfin_frame_args_address (struct frame_info *this_frame, void **this_cache) |
| 748 | { |
| 749 | struct bfin_frame_cache *cache = bfin_frame_cache (this_frame, this_cache); |
| 750 | |
| 751 | return cache->base + 8; |
| 752 | } |
| 753 | |
| 754 | static const struct frame_base bfin_frame_base = |
| 755 | { |
| 756 | &bfin_frame_unwind, |
| 757 | bfin_frame_base_address, |
| 758 | bfin_frame_local_address, |
| 759 | bfin_frame_args_address |
| 760 | }; |
| 761 | |
| 762 | static struct frame_id |
| 763 | bfin_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame) |
| 764 | { |
| 765 | CORE_ADDR sp; |
| 766 | |
| 767 | sp = get_frame_register_unsigned (this_frame, BFIN_SP_REGNUM); |
| 768 | |
| 769 | return frame_id_build (sp, get_frame_pc (this_frame)); |
| 770 | } |
| 771 | |
| 772 | static CORE_ADDR |
| 773 | bfin_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) |
| 774 | { |
| 775 | return frame_unwind_register_unsigned (next_frame, BFIN_PC_REGNUM); |
| 776 | } |
| 777 | |
| 778 | static CORE_ADDR |
| 779 | bfin_frame_align (struct gdbarch *gdbarch, CORE_ADDR address) |
| 780 | { |
| 781 | return (address & ~0x3); |
| 782 | } |
| 783 | |
| 784 | enum bfin_abi |
| 785 | bfin_abi (struct gdbarch *gdbarch) |
| 786 | { |
| 787 | return gdbarch_tdep (gdbarch)->bfin_abi; |
| 788 | } |
| 789 | |
| 790 | /* Initialize the current architecture based on INFO. If possible, |
| 791 | re-use an architecture from ARCHES, which is a list of |
| 792 | architectures already created during this debugging session. |
| 793 | |
| 794 | Called e.g. at program startup, when reading a core file, and when |
| 795 | reading a binary file. */ |
| 796 | |
| 797 | static struct gdbarch * |
| 798 | bfin_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| 799 | { |
| 800 | struct gdbarch_tdep *tdep; |
| 801 | struct gdbarch *gdbarch; |
| 802 | int elf_flags; |
| 803 | enum bfin_abi abi; |
| 804 | |
| 805 | /* Extract the ELF flags, if available. */ |
| 806 | if (info.abfd && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour) |
| 807 | elf_flags = elf_elfheader (info.abfd)->e_flags; |
| 808 | else |
| 809 | elf_flags = 0; |
| 810 | |
| 811 | abi = BFIN_ABI_FLAT; |
| 812 | |
| 813 | /* If there is already a candidate, use it. */ |
| 814 | |
| 815 | for (arches = gdbarch_list_lookup_by_info (arches, &info); |
| 816 | arches != NULL; |
| 817 | arches = gdbarch_list_lookup_by_info (arches->next, &info)) |
| 818 | { |
| 819 | if (gdbarch_tdep (arches->gdbarch)->bfin_abi != abi) |
| 820 | continue; |
| 821 | return arches->gdbarch; |
| 822 | } |
| 823 | |
| 824 | tdep = XMALLOC (struct gdbarch_tdep); |
| 825 | gdbarch = gdbarch_alloc (&info, tdep); |
| 826 | |
| 827 | tdep->bfin_abi = abi; |
| 828 | |
| 829 | set_gdbarch_num_regs (gdbarch, BFIN_NUM_REGS); |
| 830 | set_gdbarch_pseudo_register_read (gdbarch, bfin_pseudo_register_read); |
| 831 | set_gdbarch_pseudo_register_write (gdbarch, bfin_pseudo_register_write); |
| 832 | set_gdbarch_num_pseudo_regs (gdbarch, BFIN_NUM_PSEUDO_REGS); |
| 833 | set_gdbarch_sp_regnum (gdbarch, BFIN_SP_REGNUM); |
| 834 | set_gdbarch_pc_regnum (gdbarch, BFIN_PC_REGNUM); |
| 835 | set_gdbarch_ps_regnum (gdbarch, BFIN_ASTAT_REGNUM); |
| 836 | set_gdbarch_dwarf2_reg_to_regnum (gdbarch, bfin_reg_to_regnum); |
| 837 | set_gdbarch_register_name (gdbarch, bfin_register_name); |
| 838 | set_gdbarch_register_type (gdbarch, bfin_register_type); |
| 839 | set_gdbarch_dummy_id (gdbarch, bfin_dummy_id); |
| 840 | set_gdbarch_push_dummy_call (gdbarch, bfin_push_dummy_call); |
| 841 | set_gdbarch_believe_pcc_promotion (gdbarch, 1); |
| 842 | set_gdbarch_return_value (gdbarch, bfin_return_value); |
| 843 | set_gdbarch_skip_prologue (gdbarch, bfin_skip_prologue); |
| 844 | set_gdbarch_inner_than (gdbarch, core_addr_lessthan); |
| 845 | set_gdbarch_breakpoint_from_pc (gdbarch, bfin_breakpoint_from_pc); |
| 846 | set_gdbarch_decr_pc_after_break (gdbarch, 2); |
| 847 | set_gdbarch_frame_args_skip (gdbarch, 8); |
| 848 | set_gdbarch_unwind_pc (gdbarch, bfin_unwind_pc); |
| 849 | set_gdbarch_frame_align (gdbarch, bfin_frame_align); |
| 850 | set_gdbarch_print_insn (gdbarch, print_insn_bfin); |
| 851 | |
| 852 | /* Hook in ABI-specific overrides, if they have been registered. */ |
| 853 | gdbarch_init_osabi (info, gdbarch); |
| 854 | |
| 855 | dwarf2_append_unwinders (gdbarch); |
| 856 | |
| 857 | frame_base_set_default (gdbarch, &bfin_frame_base); |
| 858 | |
| 859 | frame_unwind_append_unwinder (gdbarch, &bfin_frame_unwind); |
| 860 | |
| 861 | return gdbarch; |
| 862 | } |
| 863 | |
| 864 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 865 | extern initialize_file_ftype _initialize_bfin_tdep; |
| 866 | |
| 867 | void |
| 868 | _initialize_bfin_tdep (void) |
| 869 | { |
| 870 | register_gdbarch_init (bfd_arch_bfin, bfin_gdbarch_init); |
| 871 | } |