| /* s390-dis.c -- Disassemble S390 instructions |
| Copyright 2000, 2001, 2002, 2003, 2005, 2007, 2008 |
| Free Software Foundation, Inc. |
| Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). |
| |
| This file is part of the GNU opcodes library. |
| |
| This library 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 3, or (at your option) |
| any later version. |
| |
| It 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 file; see the file COPYING. If not, write to the |
| Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| #include <stdio.h> |
| #include "ansidecl.h" |
| #include "sysdep.h" |
| #include "dis-asm.h" |
| #include "opintl.h" |
| #include "opcode/s390.h" |
| |
| static int init_flag = 0; |
| static int opc_index[256]; |
| static int current_arch_mask = 0; |
| |
| /* Set up index table for first opcode byte. */ |
| |
| static void |
| init_disasm (struct disassemble_info *info) |
| { |
| const struct s390_opcode *opcode; |
| const struct s390_opcode *opcode_end; |
| const char *p; |
| |
| memset (opc_index, 0, sizeof (opc_index)); |
| opcode_end = s390_opcodes + s390_num_opcodes; |
| for (opcode = s390_opcodes; opcode < opcode_end; opcode++) |
| { |
| opc_index[(int) opcode->opcode[0]] = opcode - s390_opcodes; |
| while ((opcode < opcode_end) && |
| (opcode[1].opcode[0] == opcode->opcode[0])) |
| opcode++; |
| } |
| |
| for (p = info->disassembler_options; p != NULL; ) |
| { |
| if (CONST_STRNEQ (p, "esa")) |
| current_arch_mask = 1 << S390_OPCODE_ESA; |
| else if (CONST_STRNEQ (p, "zarch")) |
| current_arch_mask = 1 << S390_OPCODE_ZARCH; |
| else |
| fprintf (stderr, "Unknown S/390 disassembler option: %s\n", p); |
| |
| p = strchr (p, ','); |
| if (p != NULL) |
| p++; |
| } |
| |
| if (!current_arch_mask) |
| switch (info->mach) |
| { |
| case bfd_mach_s390_31: |
| current_arch_mask = 1 << S390_OPCODE_ESA; |
| break; |
| case bfd_mach_s390_64: |
| current_arch_mask = 1 << S390_OPCODE_ZARCH; |
| break; |
| default: |
| abort (); |
| } |
| |
| init_flag = 1; |
| } |
| |
| /* Extracts an operand value from an instruction. */ |
| /* We do not perform the shift operation for larl-type address |
| operands here since that would lead to an overflow of the 32 bit |
| integer value. Instead the shift operation is done when printing |
| the operand in print_insn_s390. */ |
| |
| static inline unsigned int |
| s390_extract_operand (unsigned char *insn, const struct s390_operand *operand) |
| { |
| unsigned int val; |
| int bits; |
| |
| /* Extract fragments of the operand byte for byte. */ |
| insn += operand->shift / 8; |
| bits = (operand->shift & 7) + operand->bits; |
| val = 0; |
| do |
| { |
| val <<= 8; |
| val |= (unsigned int) *insn++; |
| bits -= 8; |
| } |
| while (bits > 0); |
| val >>= -bits; |
| val &= ((1U << (operand->bits - 1)) << 1) - 1; |
| |
| /* Check for special long displacement case. */ |
| if (operand->bits == 20 && operand->shift == 20) |
| val = (val & 0xff) << 12 | (val & 0xfff00) >> 8; |
| |
| /* Sign extend value if the operand is signed or pc relative. */ |
| if ((operand->flags & (S390_OPERAND_SIGNED | S390_OPERAND_PCREL)) |
| && (val & (1U << (operand->bits - 1)))) |
| val |= (-1U << (operand->bits - 1)) << 1; |
| |
| /* Length x in an instructions has real length x + 1. */ |
| if (operand->flags & S390_OPERAND_LENGTH) |
| val++; |
| return val; |
| } |
| |
| /* Print a S390 instruction. */ |
| |
| int |
| print_insn_s390 (bfd_vma memaddr, struct disassemble_info *info) |
| { |
| bfd_byte buffer[6]; |
| const struct s390_opcode *opcode; |
| const struct s390_opcode *opcode_end; |
| unsigned int value; |
| int status, opsize, bufsize; |
| char separator; |
| |
| if (init_flag == 0) |
| init_disasm (info); |
| |
| /* The output looks better if we put 6 bytes on a line. */ |
| info->bytes_per_line = 6; |
| |
| /* Every S390 instruction is max 6 bytes long. */ |
| memset (buffer, 0, 6); |
| status = (*info->read_memory_func) (memaddr, buffer, 6, info); |
| if (status != 0) |
| { |
| for (bufsize = 0; bufsize < 6; bufsize++) |
| if ((*info->read_memory_func) (memaddr, buffer, bufsize + 1, info) != 0) |
| break; |
| if (bufsize <= 0) |
| { |
| (*info->memory_error_func) (status, memaddr, info); |
| return -1; |
| } |
| /* Opsize calculation looks strange but it works |
| 00xxxxxx -> 2 bytes, 01xxxxxx/10xxxxxx -> 4 bytes, |
| 11xxxxxx -> 6 bytes. */ |
| opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1; |
| status = opsize > bufsize; |
| } |
| else |
| { |
| bufsize = 6; |
| opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1; |
| } |
| |
| if (status == 0) |
| { |
| const struct s390_opcode *op; |
| |
| /* Find the first match in the opcode table. */ |
| opcode_end = s390_opcodes + s390_num_opcodes; |
| for (opcode = s390_opcodes + opc_index[(int) buffer[0]]; |
| (opcode < opcode_end) && (buffer[0] == opcode->opcode[0]); |
| opcode++) |
| { |
| const struct s390_operand *operand; |
| const unsigned char *opindex; |
| |
| /* Check architecture. */ |
| if (!(opcode->modes & current_arch_mask)) |
| continue; |
| |
| /* Check signature of the opcode. */ |
| if ((buffer[1] & opcode->mask[1]) != opcode->opcode[1] |
| || (buffer[2] & opcode->mask[2]) != opcode->opcode[2] |
| || (buffer[3] & opcode->mask[3]) != opcode->opcode[3] |
| || (buffer[4] & opcode->mask[4]) != opcode->opcode[4] |
| || (buffer[5] & opcode->mask[5]) != opcode->opcode[5]) |
| continue; |
| |
| /* Advance to an opcode with a more specific mask. */ |
| for (op = opcode + 1; op < opcode_end; op++) |
| { |
| if ((buffer[0] & op->mask[0]) != op->opcode[0]) |
| break; |
| |
| if ((buffer[1] & op->mask[1]) != op->opcode[1] |
| || (buffer[2] & op->mask[2]) != op->opcode[2] |
| || (buffer[3] & op->mask[3]) != op->opcode[3] |
| || (buffer[4] & op->mask[4]) != op->opcode[4] |
| || (buffer[5] & op->mask[5]) != op->opcode[5]) |
| continue; |
| |
| if (((int)opcode->mask[0] + opcode->mask[1] + |
| opcode->mask[2] + opcode->mask[3] + |
| opcode->mask[4] + opcode->mask[5]) < |
| ((int)op->mask[0] + op->mask[1] + |
| op->mask[2] + op->mask[3] + |
| op->mask[4] + op->mask[5])) |
| opcode = op; |
| } |
| |
| /* The instruction is valid. */ |
| if (opcode->operands[0] != 0) |
| (*info->fprintf_func) (info->stream, "%s\t", opcode->name); |
| else |
| (*info->fprintf_func) (info->stream, "%s", opcode->name); |
| |
| /* Extract the operands. */ |
| separator = 0; |
| for (opindex = opcode->operands; *opindex != 0; opindex++) |
| { |
| operand = s390_operands + *opindex; |
| value = s390_extract_operand (buffer, operand); |
| |
| if ((operand->flags & S390_OPERAND_INDEX) && value == 0) |
| continue; |
| if ((operand->flags & S390_OPERAND_BASE) && |
| value == 0 && separator == '(') |
| { |
| separator = ','; |
| continue; |
| } |
| |
| if (separator) |
| (*info->fprintf_func) (info->stream, "%c", separator); |
| |
| if (operand->flags & S390_OPERAND_GPR) |
| (*info->fprintf_func) (info->stream, "%%r%i", value); |
| else if (operand->flags & S390_OPERAND_FPR) |
| (*info->fprintf_func) (info->stream, "%%f%i", value); |
| else if (operand->flags & S390_OPERAND_AR) |
| (*info->fprintf_func) (info->stream, "%%a%i", value); |
| else if (operand->flags & S390_OPERAND_CR) |
| (*info->fprintf_func) (info->stream, "%%c%i", value); |
| else if (operand->flags & S390_OPERAND_PCREL) |
| (*info->print_address_func) (memaddr + (int)value + (int)value, |
| info); |
| else if (operand->flags & S390_OPERAND_SIGNED) |
| (*info->fprintf_func) (info->stream, "%i", (int) value); |
| else |
| (*info->fprintf_func) (info->stream, "%u", value); |
| |
| if (operand->flags & S390_OPERAND_DISP) |
| { |
| separator = '('; |
| } |
| else if (operand->flags & S390_OPERAND_BASE) |
| { |
| (*info->fprintf_func) (info->stream, ")"); |
| separator = ','; |
| } |
| else |
| separator = ','; |
| } |
| |
| /* Found instruction, printed it, return its size. */ |
| return opsize; |
| } |
| /* No matching instruction found, fall through to hex print. */ |
| } |
| |
| if (bufsize >= 4) |
| { |
| value = (unsigned int) buffer[0]; |
| value = (value << 8) + (unsigned int) buffer[1]; |
| value = (value << 8) + (unsigned int) buffer[2]; |
| value = (value << 8) + (unsigned int) buffer[3]; |
| (*info->fprintf_func) (info->stream, ".long\t0x%08x", value); |
| return 4; |
| } |
| else if (bufsize >= 2) |
| { |
| value = (unsigned int) buffer[0]; |
| value = (value << 8) + (unsigned int) buffer[1]; |
| (*info->fprintf_func) (info->stream, ".short\t0x%04x", value); |
| return 2; |
| } |
| else |
| { |
| value = (unsigned int) buffer[0]; |
| (*info->fprintf_func) (info->stream, ".byte\t0x%02x", value); |
| return 1; |
| } |
| } |
| |
| void |
| print_s390_disassembler_options (FILE *stream) |
| { |
| fprintf (stream, _("\n\ |
| The following S/390 specific disassembler options are supported for use\n\ |
| with the -M switch (multiple options should be separated by commas):\n")); |
| |
| fprintf (stream, _(" esa Disassemble in ESA architecture mode\n")); |
| fprintf (stream, _(" zarch Disassemble in z/Architecture mode\n")); |
| } |