/* s390-dis.c -- Disassemble S390 instructions Copyright 2000, 2001 Free Software Foundation, Inc. Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). This file is part of GDB, GAS and the GNU binutils. 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 <stdio.h> #include "ansidecl.h" #include "sysdep.h" #include "dis-asm.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 (info) struct disassemble_info *info ATTRIBUTE_UNUSED; { const struct s390_opcode *opcode; const struct s390_opcode *opcode_end; 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++; } switch (info->mach) { case bfd_mach_s390_esa: current_arch_mask = 1 << S390_OPCODE_ESA; break; case bfd_mach_s390_esame: current_arch_mask = 1 << S390_OPCODE_ESAME; break; default: abort (); } init_flag = 1; } /* Extracts an operand value from an instruction. */ static inline unsigned int s390_extract_operand (insn, 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; /* 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; /* Double value if the operand is pc relative. */ if (operand->flags & S390_OPERAND_PCREL) val <<= 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 (memaddr, info) 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) { /* 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->architecture & 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; /* 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++) { unsigned int value; 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, info); else if (operand->flags & S390_OPERAND_SIGNED) (*info->fprintf_func) (info->stream, "%i", (int) value); else (*info->fprintf_func) (info->stream, "%i", 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; } }