1 /* s390-dis.c -- Disassemble S390 instructions
2 Copyright 2000, 2001, 2002, 2003, 2005, 2007, 2008
3 Free Software Foundation, Inc.
4 Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
6 This file is part of the GNU opcodes library.
8 This library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 It is distributed in the hope that it will be useful, but WITHOUT
14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
16 License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this file; see the file COPYING. If not, write to the
20 Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
21 MA 02110-1301, USA. */
28 #include "opcode/s390.h"
30 static int init_flag = 0;
31 static int opc_index[256];
32 static int current_arch_mask = 0;
34 /* Set up index table for first opcode byte. */
37 init_disasm (struct disassemble_info *info)
39 const struct s390_opcode *opcode;
40 const struct s390_opcode *opcode_end;
43 memset (opc_index, 0, sizeof (opc_index));
44 opcode_end = s390_opcodes + s390_num_opcodes;
45 for (opcode = s390_opcodes; opcode < opcode_end; opcode++)
47 opc_index[(int) opcode->opcode[0]] = opcode - s390_opcodes;
48 while ((opcode < opcode_end) &&
49 (opcode[1].opcode[0] == opcode->opcode[0]))
53 for (p = info->disassembler_options; p != NULL; )
55 if (CONST_STRNEQ (p, "esa"))
56 current_arch_mask = 1 << S390_OPCODE_ESA;
57 else if (CONST_STRNEQ (p, "zarch"))
58 current_arch_mask = 1 << S390_OPCODE_ZARCH;
60 fprintf (stderr, "Unknown S/390 disassembler option: %s\n", p);
67 if (!current_arch_mask)
70 case bfd_mach_s390_31:
71 current_arch_mask = 1 << S390_OPCODE_ESA;
73 case bfd_mach_s390_64:
74 current_arch_mask = 1 << S390_OPCODE_ZARCH;
83 /* Extracts an operand value from an instruction. */
85 static inline unsigned int
86 s390_extract_operand (unsigned char *insn, const struct s390_operand *operand)
91 /* Extract fragments of the operand byte for byte. */
92 insn += operand->shift / 8;
93 bits = (operand->shift & 7) + operand->bits;
98 val |= (unsigned int) *insn++;
103 val &= ((1U << (operand->bits - 1)) << 1) - 1;
105 /* Check for special long displacement case. */
106 if (operand->bits == 20 && operand->shift == 20)
107 val = (val & 0xff) << 12 | (val & 0xfff00) >> 8;
109 /* Sign extend value if the operand is signed or pc relative. */
110 if ((operand->flags & (S390_OPERAND_SIGNED | S390_OPERAND_PCREL))
111 && (val & (1U << (operand->bits - 1))))
112 val |= (-1U << (operand->bits - 1)) << 1;
114 /* Double value if the operand is pc relative. */
115 if (operand->flags & S390_OPERAND_PCREL)
118 /* Length x in an instructions has real length x + 1. */
119 if (operand->flags & S390_OPERAND_LENGTH)
124 /* Print a S390 instruction. */
127 print_insn_s390 (bfd_vma memaddr, struct disassemble_info *info)
130 const struct s390_opcode *opcode;
131 const struct s390_opcode *opcode_end;
133 int status, opsize, bufsize;
139 /* The output looks better if we put 6 bytes on a line. */
140 info->bytes_per_line = 6;
142 /* Every S390 instruction is max 6 bytes long. */
143 memset (buffer, 0, 6);
144 status = (*info->read_memory_func) (memaddr, buffer, 6, info);
147 for (bufsize = 0; bufsize < 6; bufsize++)
148 if ((*info->read_memory_func) (memaddr, buffer, bufsize + 1, info) != 0)
152 (*info->memory_error_func) (status, memaddr, info);
155 /* Opsize calculation looks strange but it works
156 00xxxxxx -> 2 bytes, 01xxxxxx/10xxxxxx -> 4 bytes,
157 11xxxxxx -> 6 bytes. */
158 opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
159 status = opsize > bufsize;
164 opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
169 /* Find the first match in the opcode table. */
170 opcode_end = s390_opcodes + s390_num_opcodes;
171 for (opcode = s390_opcodes + opc_index[(int) buffer[0]];
172 (opcode < opcode_end) && (buffer[0] == opcode->opcode[0]);
175 const struct s390_operand *operand;
176 const unsigned char *opindex;
178 /* Check architecture. */
179 if (!(opcode->modes & current_arch_mask))
181 /* Check signature of the opcode. */
182 if ((buffer[1] & opcode->mask[1]) != opcode->opcode[1]
183 || (buffer[2] & opcode->mask[2]) != opcode->opcode[2]
184 || (buffer[3] & opcode->mask[3]) != opcode->opcode[3]
185 || (buffer[4] & opcode->mask[4]) != opcode->opcode[4]
186 || (buffer[5] & opcode->mask[5]) != opcode->opcode[5])
189 /* The instruction is valid. */
190 if (opcode->operands[0] != 0)
191 (*info->fprintf_func) (info->stream, "%s\t", opcode->name);
193 (*info->fprintf_func) (info->stream, "%s", opcode->name);
195 /* Extract the operands. */
197 for (opindex = opcode->operands; *opindex != 0; opindex++)
201 operand = s390_operands + *opindex;
202 value = s390_extract_operand (buffer, operand);
204 if ((operand->flags & S390_OPERAND_INDEX) && value == 0)
206 if ((operand->flags & S390_OPERAND_BASE) &&
207 value == 0 && separator == '(')
214 (*info->fprintf_func) (info->stream, "%c", separator);
216 if (operand->flags & S390_OPERAND_GPR)
217 (*info->fprintf_func) (info->stream, "%%r%i", value);
218 else if (operand->flags & S390_OPERAND_FPR)
219 (*info->fprintf_func) (info->stream, "%%f%i", value);
220 else if (operand->flags & S390_OPERAND_AR)
221 (*info->fprintf_func) (info->stream, "%%a%i", value);
222 else if (operand->flags & S390_OPERAND_CR)
223 (*info->fprintf_func) (info->stream, "%%c%i", value);
224 else if (operand->flags & S390_OPERAND_PCREL)
225 (*info->print_address_func) (memaddr + (int) value, info);
226 else if (operand->flags & S390_OPERAND_SIGNED)
227 (*info->fprintf_func) (info->stream, "%i", (int) value);
229 (*info->fprintf_func) (info->stream, "%u", value);
231 if (operand->flags & S390_OPERAND_DISP)
235 else if (operand->flags & S390_OPERAND_BASE)
237 (*info->fprintf_func) (info->stream, ")");
244 /* Found instruction, printed it, return its size. */
247 /* No matching instruction found, fall through to hex print. */
252 value = (unsigned int) buffer[0];
253 value = (value << 8) + (unsigned int) buffer[1];
254 value = (value << 8) + (unsigned int) buffer[2];
255 value = (value << 8) + (unsigned int) buffer[3];
256 (*info->fprintf_func) (info->stream, ".long\t0x%08x", value);
259 else if (bufsize >= 2)
261 value = (unsigned int) buffer[0];
262 value = (value << 8) + (unsigned int) buffer[1];
263 (*info->fprintf_func) (info->stream, ".short\t0x%04x", value);
268 value = (unsigned int) buffer[0];
269 (*info->fprintf_func) (info->stream, ".byte\t0x%02x", value);
275 print_s390_disassembler_options (FILE *stream)
277 fprintf (stream, _("\n\
278 The following S/390 specific disassembler options are supported for use\n\
279 with the -M switch (multiple options should be separated by commas):\n"));
281 fprintf (stream, _(" esa Disassemble in ESA architecture mode\n"));
282 fprintf (stream, _(" zarch Disassemble in z/Architecture mode\n"));