diff options
Diffstat (limited to 'opcodes/vax-dis.c')
| -rw-r--r-- | opcodes/vax-dis.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/opcodes/vax-dis.c b/opcodes/vax-dis.c new file mode 100644 index 0000000..54b59f3 --- /dev/null +++ b/opcodes/vax-dis.c @@ -0,0 +1,299 @@ +/* Print VAX instructions. + Copyright (C) 1995, 1998 Free Software Foundation, Inc. + Contributed by Pauline Middelink <middelin@polyware.iaf.nl> + +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 "opcode/vax.h" +#include "dis-asm.h" + +/* Local function prototypes */ +static int +print_insn_arg PARAMS ((const char *, unsigned char *, bfd_vma, + disassemble_info *)); + +static int +print_insn_mode PARAMS ((int, unsigned char *, bfd_vma, disassemble_info *)); + +static char *reg_names[] = +{ + "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", + "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc" +}; + +/* Sign-extend an (unsigned char). */ +#if __STDC__ == 1 +#define COERCE_SIGNED_CHAR(ch) ((signed char)(ch)) +#else +#define COERCE_SIGNED_CHAR(ch) ((int)(((ch) ^ 0x80) & 0xFF) - 128) +#endif + +/* Get a 1 byte signed integer. */ +#define NEXTBYTE(p) \ + (p += 1, FETCH_DATA (info, p), \ + COERCE_SIGNED_CHAR(p[-1])) + +/* Get a 2 byte signed integer. */ +#define COERCE16(x) ((int) (((x) ^ 0x8000) - 0x8000)) +#define NEXTWORD(p) \ + (p += 2, FETCH_DATA (info, p), \ + COERCE16 ((p[-1] << 8) + p[-2])) + +/* Get a 4 byte signed integer. */ +#define COERCE32(x) ((int) (((x) ^ 0x80000000) - 0x80000000)) +#define NEXTLONG(p) \ + (p += 4, FETCH_DATA (info, p), \ + (COERCE32 ((((((p[-1] << 8) + p[-2]) << 8) + p[-3]) << 8) + p[-4]))) + +/* Maximum length of an instruction. */ +#define MAXLEN 25 + +#include <setjmp.h> + +struct private +{ + /* Points to first byte not fetched. */ + bfd_byte *max_fetched; + bfd_byte the_buffer[MAXLEN]; + bfd_vma insn_start; + jmp_buf bailout; +}; + +/* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive) + to ADDR (exclusive) are valid. Returns 1 for success, longjmps + on error. */ +#define FETCH_DATA(info, addr) \ + ((addr) <= ((struct private *)(info->private_data))->max_fetched \ + ? 1 : fetch_data ((info), (addr))) + +static int +fetch_data (info, addr) + struct disassemble_info *info; + bfd_byte *addr; +{ + int status; + struct private *priv = (struct private *) info->private_data; + bfd_vma start = priv->insn_start + (priv->max_fetched - priv->the_buffer); + + status = (*info->read_memory_func) (start, + priv->max_fetched, + addr - priv->max_fetched, + info); + if (status != 0) + { + (*info->memory_error_func) (status, start, info); + longjmp (priv->bailout, 1); + } + else + priv->max_fetched = addr; + + return 1; +} + +/* Print the vax instruction at address MEMADDR in debugged memory, + on INFO->STREAM. Returns length of the instruction, in bytes. */ + +int +print_insn_vax (memaddr, info) + bfd_vma memaddr; + disassemble_info *info; +{ + const struct vot *votp; + const char *argp = NULL; + unsigned char *arg; + struct private priv; + bfd_byte *buffer = priv.the_buffer; + + info->private_data = (PTR) &priv; + priv.max_fetched = priv.the_buffer; + priv.insn_start = memaddr; + if (setjmp (priv.bailout) != 0) + { + /* Error return. */ + return -1; + } + + FETCH_DATA (info, buffer + 2); + for (votp = &votstrs[0]; votp->name[0]; votp++) + { + register vax_opcodeT opcode = votp->detail.code; + + /* 2 byte codes match 2 buffer pos. */ + if ((bfd_byte) opcode == buffer[0] + && (opcode >> 8 == 0 || opcode >> 8 == buffer[1])) + { + argp = votp->detail.args; + break; + } + } + if (argp == NULL) + { + /* Handle undefined instructions. */ + (*info->fprintf_func) (info->stream, ".word 0x%x", + (buffer[0] << 8) + buffer[1]); + return 2; + } + + /* Point at first byte of argument data, and at descriptor for first + argument. */ + arg = buffer + ((votp->detail.code >> 8) ? 2 : 1); + + /* Make sure we have it in mem */ + FETCH_DATA (info, arg); + + (*info->fprintf_func) (info->stream, "%s", votp->name); + if (*argp) + (*info->fprintf_func) (info->stream, " "); + + while (*argp) + { + arg += print_insn_arg (argp, arg, memaddr + arg - buffer, info); + argp += 2; + if (*argp) + (*info->fprintf_func) (info->stream, ","); + } + + return arg - buffer; +} + +/* Returns number of bytes "eaten" by the operand, or return -1 if an + invalid operand was found, or -2 if an opcode tabel error was + found. */ + +static int +print_insn_arg (d, p0, addr, info) + const char *d; + unsigned char *p0; + bfd_vma addr; /* PC for this arg to be relative to */ + disassemble_info *info; +{ + int arg_len; + + /* check validity of addressing length */ + switch (d[1]) + { + case 'b' : arg_len = 1; break; + case 'd' : arg_len = 8; break; + case 'f' : arg_len = 4; break; + case 'g' : arg_len = 8; break; + case 'h' : arg_len = 16; break; + case 'l' : arg_len = 4; break; + case 'o' : arg_len = 16; break; + case 'w' : arg_len = 2; break; + case 'q' : arg_len = 8; break; + default : abort(); + } + + /* branches have no mode byte */ + if (d[0] == 'b') + { + unsigned char *p = p0; + + if (arg_len == 1) + (*info->print_address_func) (addr + 1 + NEXTBYTE (p), info); + else + (*info->print_address_func) (addr + 2 + NEXTWORD (p), info); + + return p - p0; + } + + return print_insn_mode (arg_len, p0, addr, info); +} + +static int +print_insn_mode (size, p0, addr, info) + int size; + unsigned char *p0; + bfd_vma addr; /* PC for this arg to be relative to */ + disassemble_info *info; +{ + unsigned char *p = p0; + unsigned char mode, reg; + + /* fetch and interpret mode byte */ + mode = (unsigned char) NEXTBYTE (p); + reg = mode & 0xF; + switch (mode & 0xF0) + { + case 0x00: + case 0x10: + case 0x20: + case 0x30: /* literal mode $number */ + (*info->fprintf_func) (info->stream, "$0x%x", mode); + break; + case 0x40: /* index: base-addr[Rn] */ + p += print_insn_mode (size, p0 + 1, addr + 1, info); + (*info->fprintf_func) (info->stream, "[%s]", reg_names[reg]); + break; + case 0x50: /* register: Rn */ + (*info->fprintf_func) (info->stream, "%s", reg_names[reg]); + break; + case 0x60: /* register deferred: (Rn) */ + (*info->fprintf_func) (info->stream, "(%s)", reg_names[reg]); + break; + case 0x70: /* autodecrement: -(Rn) */ + (*info->fprintf_func) (info->stream, "-(%s)", reg_names[reg]); + break; + case 0x80: /* autoincrement: (Rn)+ */ + if (reg == 0xF) + { /* immediate? */ + int i; + + FETCH_DATA (info, p + size); + (*info->fprintf_func) (info->stream, "$0x"); + for (i = 0; i < size; i++) + (*info->fprintf_func) (info->stream, "%02x", p[size - i - 1]); + p += size; + } + else + (*info->fprintf_func) (info->stream, "(%s)+", reg_names[reg]); + break; + case 0x90: /* autoincrement deferred: @(Rn)+ */ + if (reg == 0xF) + (*info->fprintf_func) (info->stream, "*0x%x", NEXTLONG (p)); + else + (*info->fprintf_func) (info->stream, "@(%s)+", reg_names[reg]); + break; + case 0xB0: /* displacement byte deferred: *displ(Rn) */ + (*info->fprintf_func) (info->stream, "*"); + case 0xA0: /* displacement byte: displ(Rn) */ + if (reg == 0xF) + (*info->print_address_func) (addr + 2 + NEXTBYTE (p), info); + else + (*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTBYTE (p), + reg_names[reg]); + break; + case 0xD0: /* displacement word deferred: *displ(Rn) */ + (*info->fprintf_func) (info->stream, "*"); + case 0xC0: /* displacement word: displ(Rn) */ + if (reg == 0xF) + (*info->print_address_func) (addr + 3 + NEXTWORD (p), info); + else + (*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTWORD (p), + reg_names[reg]); + break; + case 0xF0: /* displacement long deferred: *displ(Rn) */ + (*info->fprintf_func) (info->stream, "*"); + case 0xE0: /* displacement long: displ(Rn) */ + if (reg == 0xF) + (*info->print_address_func) (addr + 5 + NEXTLONG (p), info); + else + (*info->fprintf_func) (info->stream, "0x%x(%s)", NEXTLONG (p), + reg_names[reg]); + break; + } + + return p - p0; +} |