| /* Print DEC PDP-11 instructions. |
| Copyright 2001, 2002 Free Software Foundation, Inc. |
| |
| This file 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" |
| #include "opcode/pdp11.h" |
| |
| #define AFTER_INSTRUCTION "\t" |
| #define OPERAND_SEPARATOR ", " |
| |
| #define JUMP 0x1000 /* flag that this operand is used in a jump */ |
| |
| #define FPRINTF (*info->fprintf_func) |
| #define F info->stream |
| |
| /* sign-extend a 16-bit number in an int */ |
| #define SIGN_BITS (8 * sizeof (int) - 16) |
| #define sign_extend(x) (((x) << SIGN_BITS) >> SIGN_BITS) |
| |
| static int read_word PARAMS ((bfd_vma memaddr, int *word, |
| disassemble_info *info)); |
| static void print_signed_octal PARAMS ((int n, disassemble_info *info)); |
| static void print_reg PARAMS ((int reg, disassemble_info *info)); |
| static void print_freg PARAMS ((int freg, disassemble_info *info)); |
| static int print_operand PARAMS ((bfd_vma *memaddr, int code, |
| disassemble_info *info)); |
| static int print_foperand PARAMS ((bfd_vma *memaddr, int code, |
| disassemble_info *info)); |
| int print_insn_pdp11 PARAMS ((bfd_vma memaddr, disassemble_info *info)); |
| |
| static int |
| read_word (memaddr, word, info) |
| bfd_vma memaddr; |
| int *word; |
| disassemble_info *info; |
| { |
| int status; |
| bfd_byte x[2]; |
| |
| status = (*info->read_memory_func) (memaddr, x, 2, info); |
| if (status != 0) |
| return -1; |
| |
| *word = x[1] << 8 | x[0]; |
| return 0; |
| } |
| |
| static void |
| print_signed_octal (n, info) |
| int n; |
| disassemble_info *info; |
| { |
| if (n < 0) |
| FPRINTF (F, "-%o", -n); |
| else |
| FPRINTF (F, "%o", n); |
| } |
| |
| static void |
| print_reg (reg, info) |
| int reg; |
| disassemble_info *info; |
| { |
| /* mask off the addressing mode, if any */ |
| reg &= 7; |
| |
| switch (reg) |
| { |
| case 0: case 1: case 2: case 3: case 4: case 5: |
| FPRINTF (F, "r%d", reg); break; |
| case 6: FPRINTF (F, "sp"); break; |
| case 7: FPRINTF (F, "pc"); break; |
| default: /* error */ |
| } |
| } |
| |
| static void |
| print_freg (freg, info) |
| int freg; |
| disassemble_info *info; |
| { |
| FPRINTF (F, "fr%d", freg); |
| } |
| |
| static int |
| print_operand (memaddr, code, info) |
| bfd_vma *memaddr; |
| int code; |
| disassemble_info *info; |
| { |
| int mode = (code >> 3) & 7; |
| int reg = code & 7; |
| int disp; |
| |
| switch (mode) |
| { |
| case 0: |
| print_reg (reg, info); |
| break; |
| case 1: |
| FPRINTF (F, "("); |
| print_reg (reg, info); |
| FPRINTF (F, ")"); |
| break; |
| case 2: |
| if (reg == 7) |
| { |
| int data; |
| if (read_word (*memaddr, &data, info) < 0) |
| return -1; |
| FPRINTF (F, "$"); |
| print_signed_octal (sign_extend (data), info); |
| *memaddr += 2; |
| } |
| else |
| { |
| FPRINTF (F, "("); |
| print_reg (reg, info); |
| FPRINTF (F, ")+"); |
| } |
| break; |
| case 3: |
| if (reg == 7) |
| { |
| int address; |
| if (read_word (*memaddr, &address, info) < 0) |
| return -1; |
| FPRINTF (F, "*$%o", address); |
| *memaddr += 2; |
| } |
| else |
| { |
| FPRINTF (F, "*("); |
| print_reg (reg, info); |
| FPRINTF (F, ")+"); |
| } |
| break; |
| case 4: |
| FPRINTF (F, "-("); |
| print_reg (reg, info); |
| FPRINTF (F, ")"); |
| break; |
| case 5: |
| FPRINTF (F, "*-("); |
| print_reg (reg, info); |
| FPRINTF (F, ")"); |
| break; |
| case 6: |
| case 7: |
| if (read_word (*memaddr, &disp, info) < 0) |
| return -1; |
| *memaddr += 2; |
| if (reg == 7) |
| { |
| bfd_vma address = *memaddr + sign_extend (disp); |
| if (mode == 7) |
| FPRINTF (F, "*"); |
| if (!(code & JUMP)) |
| FPRINTF (F, "$"); |
| (*info->print_address_func) (address, info); |
| } |
| else |
| { |
| if (mode == 7) |
| FPRINTF (F, "*"); |
| print_signed_octal (sign_extend (disp), info); |
| FPRINTF (F, "("); |
| print_reg (reg, info); |
| FPRINTF (F, ")"); |
| } |
| break; |
| } |
| |
| return 0; |
| } |
| |
| static int |
| print_foperand (memaddr, code, info) |
| bfd_vma *memaddr; |
| int code; |
| disassemble_info *info; |
| { |
| int mode = (code >> 3) & 7; |
| int reg = code & 7; |
| |
| if (mode == 0) |
| print_freg (reg, info); |
| else |
| return print_operand (memaddr, code, info); |
| |
| return 0; |
| } |
| |
| /* Print the PDP-11 instruction at address MEMADDR in debugged memory, |
| on INFO->STREAM. Returns length of the instruction, in bytes. */ |
| |
| int |
| print_insn_pdp11 (memaddr, info) |
| bfd_vma memaddr; |
| disassemble_info *info; |
| { |
| bfd_vma start_memaddr = memaddr; |
| int opcode; |
| int src, dst; |
| int i; |
| |
| info->bytes_per_line = 6; |
| info->bytes_per_chunk = 2; |
| info->display_endian = BFD_ENDIAN_LITTLE; |
| |
| if (read_word (memaddr, &opcode, info) != 0) |
| return -1; |
| memaddr += 2; |
| |
| src = (opcode >> 6) & 0x3f; |
| dst = opcode & 0x3f; |
| |
| for (i = 0; i < pdp11_num_opcodes; i++) |
| { |
| #define OP pdp11_opcodes[i] |
| if ((opcode & OP.mask) == OP.opcode) |
| switch (OP.type) |
| { |
| case PDP11_OPCODE_NO_OPS: |
| FPRINTF (F, OP.name); |
| goto done; |
| case PDP11_OPCODE_REG: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| print_reg (dst, info); |
| goto done; |
| case PDP11_OPCODE_OP: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (strcmp (OP.name, "jmp") == 0) |
| dst |= JUMP; |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| case PDP11_OPCODE_FOP: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (strcmp (OP.name, "jmp") == 0) |
| dst |= JUMP; |
| if (print_foperand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| case PDP11_OPCODE_REG_OP: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| print_reg (src, info); |
| FPRINTF (F, OPERAND_SEPARATOR); |
| if (strcmp (OP.name, "jsr") == 0) |
| dst |= JUMP; |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| case PDP11_OPCODE_REG_OP_REV: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| FPRINTF (F, OPERAND_SEPARATOR); |
| print_reg (src, info); |
| goto done; |
| case PDP11_OPCODE_AC_FOP: |
| { |
| int ac = (opcode & 0xe0) >> 6; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| print_freg (ac, info); |
| FPRINTF (F, OPERAND_SEPARATOR); |
| if (print_foperand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| } |
| case PDP11_OPCODE_FOP_AC: |
| { |
| int ac = (opcode & 0xe0) >> 6; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (print_foperand (&memaddr, dst, info) < 0) |
| return -1; |
| FPRINTF (F, OPERAND_SEPARATOR); |
| print_freg (ac, info); |
| goto done; |
| } |
| case PDP11_OPCODE_AC_OP: |
| { |
| int ac = (opcode & 0xe0) >> 6; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| print_freg (ac, info); |
| FPRINTF (F, OPERAND_SEPARATOR); |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| } |
| case PDP11_OPCODE_OP_AC: |
| { |
| int ac = (opcode & 0xe0) >> 6; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| FPRINTF (F, OPERAND_SEPARATOR); |
| print_freg (ac, info); |
| goto done; |
| } |
| case PDP11_OPCODE_OP_OP: |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| if (print_operand (&memaddr, src, info) < 0) |
| return -1; |
| FPRINTF (F, OPERAND_SEPARATOR); |
| if (print_operand (&memaddr, dst, info) < 0) |
| return -1; |
| goto done; |
| case PDP11_OPCODE_DISPL: |
| { |
| int displ = (opcode & 0xff) << 8; |
| bfd_vma address = memaddr + (sign_extend (displ) >> 7); |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| (*info->print_address_func) (address, info); |
| goto done; |
| } |
| case PDP11_OPCODE_REG_DISPL: |
| { |
| int displ = (opcode & 0x3f) << 10; |
| bfd_vma address = memaddr + (sign_extend (displ) >> 9); |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| print_reg (src, info); |
| FPRINTF (F, OPERAND_SEPARATOR); |
| (*info->print_address_func) (address, info); |
| goto done; |
| } |
| case PDP11_OPCODE_IMM8: |
| { |
| int code = opcode & 0xff; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| FPRINTF (F, "%o", code); |
| goto done; |
| } |
| case PDP11_OPCODE_IMM6: |
| { |
| int code = opcode & 0x3f; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| FPRINTF (F, "%o", code); |
| goto done; |
| } |
| case PDP11_OPCODE_IMM3: |
| { |
| int code = opcode & 7; |
| FPRINTF (F, OP.name); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| FPRINTF (F, "%o", code); |
| goto done; |
| } |
| case PDP11_OPCODE_ILLEGAL: |
| { |
| FPRINTF (F, ".word"); |
| FPRINTF (F, AFTER_INSTRUCTION); |
| FPRINTF (F, "%o", opcode); |
| goto done; |
| } |
| default: |
| /* TODO: is this a proper way of signalling an error? */ |
| FPRINTF (F, "<internal error: unrecognized instruction type>"); |
| return -1; |
| } |
| #undef OP |
| } |
| done: |
| |
| return memaddr - start_memaddr; |
| } |