/* Instruction printing code for the ARM Copyright (C) 1994, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc. Contributed by Richard Earnshaw (rwe@pegasus.esprit.ec.org) Modification by James G. Smith (jsmith@cygnus.co.uk) This file is part of libopcodes. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "sysdep.h" #include "dis-asm.h" #define DEFINE_TABLE #include "arm-opc.h" #include "coff/internal.h" #include "libcoff.h" #include "opintl.h" /* FIXME: This shouldn't be done here */ #include "elf-bfd.h" #include "elf/internal.h" #include "elf/arm.h" #ifndef streq #define streq(a,b) (strcmp ((a), (b)) == 0) #endif #ifndef strneq #define strneq(a,b,n) (strncmp ((a), (b), (n)) == 0) #endif #ifndef NUM_ELEM #define NUM_ELEM(a) (sizeof (a) / sizeof (a)[0]) #endif static char * arm_conditional[] = {"eq", "ne", "cs", "cc", "mi", "pl", "vs", "vc", "hi", "ls", "ge", "lt", "gt", "le", "", "nv"}; typedef struct { const char * name; const char * description; const char * reg_names[16]; } arm_regname; static arm_regname regnames[] = { { "raw" , "Select raw register names", { "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"}}, { "std", "Select register names used in ARM's ISA documentation", { "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "sp", "lr", "pc" }}, { "apcs", "Select register names used in the APCS", { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "v4", "v5", "v6", "sl", "fp", "ip", "sp", "lr", "pc" }}, { "atpcs", "Select register names used in the ATPCS", { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v8", "IP", "SP", "LR", "PC" }}, { "atpcs-special", "Select special register names used in the ATPCS", { "a1", "a2", "a3", "a4", "v1", "v2", "v3", "WR", "v5", "SB", "SL", "FP", "IP", "SP", "LR", "PC" }} }; /* Default to standard register name set. */ static unsigned int regname_selected = 1; #define NUM_ARM_REGNAMES NUM_ELEM (regnames) #define arm_regnames regnames[regname_selected].reg_names static boolean force_thumb = false; static char * arm_fp_const[] = {"0.0", "1.0", "2.0", "3.0", "4.0", "5.0", "0.5", "10.0"}; static char * arm_shift[] = {"lsl", "lsr", "asr", "ror"}; /* Forward declarations. */ static void arm_decode_shift PARAMS ((long, fprintf_ftype, void *)); static int print_insn_arm PARAMS ((bfd_vma, struct disassemble_info *, long)); static int print_insn_thumb PARAMS ((bfd_vma, struct disassemble_info *, long)); static void parse_disassembler_options PARAMS ((char *)); static int print_insn PARAMS ((bfd_vma, struct disassemble_info *, boolean)); /* Functions. */ static void arm_decode_shift (given, func, stream) long given; fprintf_ftype func; void * stream; { func (stream, "%s", arm_regnames[given & 0xf]); if ((given & 0xff0) != 0) { if ((given & 0x10) == 0) { int amount = (given & 0xf80) >> 7; int shift = (given & 0x60) >> 5; if (amount == 0) { if (shift == 3) { func (stream, ", rrx"); return; } amount = 32; } func (stream, ", %s #%d", arm_shift[shift], amount); } else func (stream, ", %s %s", arm_shift[(given & 0x60) >> 5], arm_regnames[(given & 0xf00) >> 8]); } } /* Print one instruction from PC on INFO->STREAM. Return the size of the instruction (always 4 on ARM). */ static int print_insn_arm (pc, info, given) bfd_vma pc; struct disassemble_info * info; long given; { struct arm_opcode * insn; void * stream = info->stream; fprintf_ftype func = info->fprintf_func; for (insn = arm_opcodes; insn->assembler; insn++) { if ((given & insn->mask) == insn->value) { char * c; for (c = insn->assembler; *c; c++) { if (*c == '%') { switch (*++c) { case '%': func (stream, "%%"); break; case 'a': if (((given & 0x000f0000) == 0x000f0000) && ((given & 0x02000000) == 0)) { int offset = given & 0xfff; func (stream, "[pc"); if (given & 0x01000000) { if ((given & 0x00800000) == 0) offset = - offset; /* pre-indexed */ func (stream, ", #%x]", offset); offset += pc + 8; /* Cope with the possibility of write-back being used. Probably a very dangerous thing for the programmer to do, but who are we to argue ? */ if (given & 0x00200000) func (stream, "!"); } else { /* Post indexed. */ func (stream, "], #%x", offset); offset = pc + 8; /* ie ignore the offset. */ } func (stream, "\t; "); info->print_address_func (offset, info); } else { func (stream, "[%s", arm_regnames[(given >> 16) & 0xf]); if ((given & 0x01000000) != 0) { if ((given & 0x02000000) == 0) { int offset = given & 0xfff; if (offset) func (stream, ", %s#%d", (((given & 0x00800000) == 0) ? "-" : ""), offset); } else { func (stream, ", %s", (((given & 0x00800000) == 0) ? "-" : "")); arm_decode_shift (given, func, stream); } func (stream, "]%s", ((given & 0x00200000) != 0) ? "!" : ""); } else { if ((given & 0x02000000) == 0) { int offset = given & 0xfff; if (offset) func (stream, "], %s#%d", (((given & 0x00800000) == 0) ? "-" : ""), offset); else func (stream, "]"); } else { func (stream, "], %s", (((given & 0x00800000) == 0) ? "-" : "")); arm_decode_shift (given, func, stream); } } } break; case 's': if ((given & 0x004f0000) == 0x004f0000) { /* PC relative with immediate offset. */ int offset = ((given & 0xf00) >> 4) | (given & 0xf); if ((given & 0x00800000) == 0) offset = -offset; func (stream, "[pc, #%x]\t; ", offset); (*info->print_address_func) (offset + pc + 8, info); } else { func (stream, "[%s", arm_regnames[(given >> 16) & 0xf]); if ((given & 0x01000000) != 0) { /* Pre-indexed. */ if ((given & 0x00400000) == 0x00400000) { /* Immediate. */ int offset = ((given & 0xf00) >> 4) | (given & 0xf); if (offset) func (stream, ", %s#%d", (((given & 0x00800000) == 0) ? "-" : ""), offset); } else { /* Register. */ func (stream, ", %s%s", (((given & 0x00800000) == 0) ? "-" : ""), arm_regnames[given & 0xf]); } func (stream, "]%s", ((given & 0x00200000) != 0) ? "!" : ""); } else { /* Post-indexed. */ if ((given & 0x00400000) == 0x00400000) { /* Immediate. */ int offset = ((given & 0xf00) >> 4) | (given & 0xf); if (offset) func (stream, "], %s#%d", (((given & 0x00800000) == 0) ? "-" : ""), offset); else func (stream, "]"); } else { /* Register. */ func (stream, "], %s%s", (((given & 0x00800000) == 0) ? "-" : ""), arm_regnames[given & 0xf]); } } } break; case 'b': (*info->print_address_func) (BDISP (given) * 4 + pc + 8, info); break; case 'c': func (stream, "%s", arm_conditional [(given >> 28) & 0xf]); break; case 'm': { int started = 0; int reg; func (stream, "{"); for (reg = 0; reg < 16; reg++) if ((given & (1 << reg)) != 0) { if (started) func (stream, ", "); started = 1; func (stream, "%s", arm_regnames[reg]); } func (stream, "}"); } break; case 'o': if ((given & 0x02000000) != 0) { int rotate = (given & 0xf00) >> 7; int immed = (given & 0xff); immed = (((immed << (32 - rotate)) | (immed >> rotate)) & 0xffffffff); func (stream, "#%d\t; 0x%x", immed, immed); } else arm_decode_shift (given, func, stream); break; case 'p': if ((given & 0x0000f000) == 0x0000f000) func (stream, "p"); break; case 't': if ((given & 0x01200000) == 0x00200000) func (stream, "t"); break; case 'h': if ((given & 0x00000020) == 0x00000020) func (stream, "h"); else func (stream, "b"); break; case 'A': func (stream, "[%s", arm_regnames [(given >> 16) & 0xf]); if ((given & 0x01000000) != 0) { int offset = given & 0xff; if (offset) func (stream, ", %s#%d]%s", ((given & 0x00800000) == 0 ? "-" : ""), offset * 4, ((given & 0x00200000) != 0 ? "!" : "")); else func (stream, "]"); } else { int offset = given & 0xff; if (offset) func (stream, "], %s#%d", ((given & 0x00800000) == 0 ? "-" : ""), offset * 4); else func (stream, "]"); } break; case 'C': switch (given & 0x00090000) { default: func (stream, "_???"); break; case 0x90000: func (stream, "_all"); break; case 0x10000: func (stream, "_ctl"); break; case 0x80000: func (stream, "_flg"); break; } break; case 'F': switch (given & 0x00408000) { case 0: func (stream, "4"); break; case 0x8000: func (stream, "1"); break; case 0x00400000: func (stream, "2"); break; default: func (stream, "3"); } break; case 'P': switch (given & 0x00080080) { case 0: func (stream, "s"); break; case 0x80: func (stream, "d"); break; case 0x00080000: func (stream, "e"); break; default: func (stream, _("")); break; } break; case 'Q': switch (given & 0x00408000) { case 0: func (stream, "s"); break; case 0x8000: func (stream, "d"); break; case 0x00400000: func (stream, "e"); break; default: func (stream, "p"); break; } break; case 'R': switch (given & 0x60) { case 0: break; case 0x20: func (stream, "p"); break; case 0x40: func (stream, "m"); break; default: func (stream, "z"); break; } break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': { int bitstart = *c++ - '0'; int bitend = 0; while (*c >= '0' && *c <= '9') bitstart = (bitstart * 10) + *c++ - '0'; switch (*c) { case '-': c++; while (*c >= '0' && *c <= '9') bitend = (bitend * 10) + *c++ - '0'; if (!bitend) abort (); switch (*c) { case 'r': { long reg; reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; func (stream, "%s", arm_regnames[reg]); } break; case 'd': { long reg; reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; func (stream, "%d", reg); } break; case 'x': { long reg; reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; func (stream, "0x%08x", reg); /* Some SWI instructions have special meanings. */ if ((given & 0x0fffffff) == 0x0FF00000) func (stream, "\t; IMB"); else if ((given & 0x0fffffff) == 0x0FF00001) func (stream, "\t; IMBRange"); } break; case 'X': { long reg; reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; func (stream, "%01x", reg & 0xf); } break; case 'f': { long reg; reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; if (reg > 7) func (stream, "#%s", arm_fp_const[reg & 7]); else func (stream, "f%d", reg); } break; default: abort (); } break; case '`': c++; if ((given & (1 << bitstart)) == 0) func (stream, "%c", *c); break; case '\'': c++; if ((given & (1 << bitstart)) != 0) func (stream, "%c", *c); break; case '?': ++c; if ((given & (1 << bitstart)) != 0) func (stream, "%c", *c++); else func (stream, "%c", *++c); break; default: abort (); } break; default: abort (); } } } else func (stream, "%c", *c); } return 4; } } abort (); } /* Print one instruction from PC on INFO->STREAM. Return the size of the instruction. */ static int print_insn_thumb (pc, info, given) bfd_vma pc; struct disassemble_info * info; long given; { struct thumb_opcode * insn; void * stream = info->stream; fprintf_ftype func = info->fprintf_func; for (insn = thumb_opcodes; insn->assembler; insn++) { if ((given & insn->mask) == insn->value) { char * c = insn->assembler; /* Special processing for Thumb 2 instruction BL sequence: */ if (!*c) /* Check for empty (not NULL) assembler string. */ { info->bytes_per_chunk = 4; info->bytes_per_line = 4; func (stream, "bl\t"); info->print_address_func (BDISP23 (given) * 2 + pc + 4, info); return 4; } else { info->bytes_per_chunk = 2; info->bytes_per_line = 4; given &= 0xffff; for (; *c; c++) { if (*c == '%') { int domaskpc = 0; int domasklr = 0; switch (*++c) { case '%': func (stream, "%%"); break; case 'S': { long reg; reg = (given >> 3) & 0x7; if (given & (1 << 6)) reg += 8; func (stream, "%s", arm_regnames[reg]); } break; case 'D': { long reg; reg = given & 0x7; if (given & (1 << 7)) reg += 8; func (stream, "%s", arm_regnames[reg]); } break; case 'T': func (stream, "%s", arm_conditional [(given >> 8) & 0xf]); break; case 'N': if (given & (1 << 8)) domasklr = 1; /* Fall through. */ case 'O': if (*c == 'O' && (given & (1 << 8))) domaskpc = 1; /* Fall through. */ case 'M': { int started = 0; int reg; func (stream, "{"); /* It would be nice if we could spot ranges, and generate the rS-rE format: */ for (reg = 0; (reg < 8); reg++) if ((given & (1 << reg)) != 0) { if (started) func (stream, ", "); started = 1; func (stream, "%s", arm_regnames[reg]); } if (domasklr) { if (started) func (stream, ", "); started = 1; func (stream, "lr"); } if (domaskpc) { if (started) func (stream, ", "); func (stream, "pc"); } func (stream, "}"); } break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': { int bitstart = *c++ - '0'; int bitend = 0; while (*c >= '0' && *c <= '9') bitstart = (bitstart * 10) + *c++ - '0'; switch (*c) { case '-': { long reg; c++; while (*c >= '0' && *c <= '9') bitend = (bitend * 10) + *c++ - '0'; if (!bitend) abort (); reg = given >> bitstart; reg &= (2 << (bitend - bitstart)) - 1; switch (*c) { case 'r': func (stream, "%s", arm_regnames[reg]); break; case 'd': func (stream, "%d", reg); break; case 'H': func (stream, "%d", reg << 1); break; case 'W': func (stream, "%d", reg << 2); break; case 'a': /* PC-relative address -- the bottom two bits of the address are dropped before the calculation. */ info->print_address_func (((pc + 4) & ~3) + (reg << 2), info); break; case 'x': func (stream, "0x%04x", reg); break; case 'I': reg = ((reg ^ (1 << bitend)) - (1 << bitend)); func (stream, "%d", reg); break; case 'B': reg = ((reg ^ (1 << bitend)) - (1 << bitend)); (*info->print_address_func) (reg * 2 + pc + 4, info); break; default: abort (); } } break; case '\'': c++; if ((given & (1 << bitstart)) != 0) func (stream, "%c", *c); break; case '?': ++c; if ((given & (1 << bitstart)) != 0) func (stream, "%c", *c++); else func (stream, "%c", *++c); break; default: abort (); } } break; default: abort (); } } else func (stream, "%c", *c); } } return 2; } } /* No match. */ abort (); } /* Parse an individual disassembler option. */ void parse_arm_disassembler_option (option) char * option; { if (option == NULL) return; if (strneq (option, "reg-names-", 10)) { int i; option += 10; for (i = NUM_ARM_REGNAMES; i--;) if (streq (option, regnames[i].name)) { regname_selected = i; break; } if (i < 0) fprintf (stderr, _("Unrecognised register name set: %s\n"), option); } else if (streq (option, "force-thumb")) force_thumb = 1; else if (streq (option, "no-force-thumb")) force_thumb = 0; else fprintf (stderr, _("Unrecognised disassembler option: %s\n"), option); return; } /* Parse the string of disassembler options, spliting it at whitespaces. */ static void parse_disassembler_options (options) char * options; { char * space; if (options == NULL) return; do { space = strchr (options, ' '); if (space) { * space = '\0'; parse_arm_disassembler_option (options); * space = ' '; options = space + 1; } else parse_arm_disassembler_option (options); } while (space); } /* NOTE: There are no checks in these routines that the relevant number of data bytes exist. */ static int print_insn (pc, info, little) bfd_vma pc; struct disassemble_info * info; boolean little; { unsigned char b[4]; long given; int status; int is_thumb; if (info->disassembler_options) { parse_disassembler_options (info->disassembler_options); /* To avoid repeated parsing of these options, we remove them here. */ info->disassembler_options = NULL; } is_thumb = force_thumb; if (!is_thumb && info->symbols != NULL) { if (bfd_asymbol_flavour (*info->symbols) == bfd_target_coff_flavour) { coff_symbol_type * cs; cs = coffsymbol (*info->symbols); is_thumb = ( cs->native->u.syment.n_sclass == C_THUMBEXT || cs->native->u.syment.n_sclass == C_THUMBSTAT || cs->native->u.syment.n_sclass == C_THUMBLABEL || cs->native->u.syment.n_sclass == C_THUMBEXTFUNC || cs->native->u.syment.n_sclass == C_THUMBSTATFUNC); } else if (bfd_asymbol_flavour (*info->symbols) == bfd_target_elf_flavour) { elf_symbol_type * es; unsigned int type; es = *(elf_symbol_type **)(info->symbols); type = ELF_ST_TYPE (es->internal_elf_sym.st_info); is_thumb = (type == STT_ARM_TFUNC) || (type == STT_ARM_16BIT); } } info->bytes_per_chunk = 4; info->display_endian = little ? BFD_ENDIAN_LITTLE : BFD_ENDIAN_BIG; if (little) { status = info->read_memory_func (pc, (bfd_byte *) &b[0], 4, info); if (status != 0 && is_thumb) { info->bytes_per_chunk = 2; status = info->read_memory_func (pc, (bfd_byte *) b, 2, info); b[3] = b[2] = 0; } if (status != 0) { info->memory_error_func (status, pc, info); return -1; } given = (b[0]) | (b[1] << 8) | (b[2] << 16) | (b[3] << 24); } else { status = info->read_memory_func (pc & ~ 0x3, (bfd_byte *) &b[0], 4, info); if (status != 0) { info->memory_error_func (status, pc, info); return -1; } if (is_thumb) { if (pc & 0x2) { given = (b[2] << 8) | b[3]; status = info->read_memory_func ((pc + 4) & ~ 0x3, (bfd_byte *) b, 4, info); if (status != 0) { info->memory_error_func (status, pc + 4, info); return -1; } given |= (b[0] << 24) | (b[1] << 16); } else given = (b[0] << 8) | b[1] | (b[2] << 24) | (b[3] << 16); } else given = (b[0] << 24) | (b[1] << 16) | (b[2] << 8) | (b[3]); } if (is_thumb) status = print_insn_thumb (pc, info, given); else status = print_insn_arm (pc, info, given); return status; } int print_insn_big_arm (pc, info) bfd_vma pc; struct disassemble_info * info; { return print_insn (pc, info, false); } int print_insn_little_arm (pc, info) bfd_vma pc; struct disassemble_info * info; { return print_insn (pc, info, true); } void print_arm_disassembler_options (FILE * stream) { int i; fprintf (stream, _("\n\ The following ARM specific disassembler options are supported for use with\n\ the -M switch:\n")); for (i = NUM_ARM_REGNAMES; i--;) fprintf (stream, " reg-names-%s %*c%s\n", regnames[i].name, 14 - strlen (regnames[i].name), ' ', regnames[i].description); fprintf (stream, " force-thumb Assume all insns are Thumb insns\n"); fprintf (stream, " no-force-thumb Examine preceeding label to determine an insn's type\n\n"); }