1 /* i370-dis.c -- Disassemble Instruction 370 (ESA/390) instructions
2 Copyright 1994, 2000, 2003, 2005 Free Software Foundation, Inc.
3 PowerPC version written by Ian Lance Taylor, Cygnus Support
4 Rewritten for i370 ESA/390 support by Linas Vepstas <linas@linas.org>
5
6 This file is part of GDB, GAS, and the GNU binutils.
7
8 GDB, GAS, and the GNU binutils are free software; you can redistribute
9 them and/or modify them under the terms of the GNU General Public
10 License as published by the Free Software Foundation; either version
11 2, or (at your option) any later version.
12
13 GDB, GAS, and the GNU binutils are distributed in the hope that they
14 will be useful, but WITHOUT ANY WARRANTY; without even the implied
15 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 the GNU General Public License for more details.
17
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 Free
20 Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
21 MA 02110-1301, USA. */
22
23 #include <stdio.h>
24 #include "sysdep.h"
25 #include "dis-asm.h"
26 #include "opcode/i370.h"
27
28 /* This file provides several disassembler functions, all of which use
29 the disassembler interface defined in dis-asm.h. */
30
31 int
print_insn_i370(bfd_vma memaddr,struct disassemble_info * info)32 print_insn_i370 (bfd_vma memaddr, struct disassemble_info *info)
33 {
34 bfd_byte buffer[8];
35 int status;
36 i370_insn_t insn;
37 const struct i370_opcode *opcode;
38 const struct i370_opcode *opcode_end;
39
40 status = (*info->read_memory_func) (memaddr, buffer, 6, info);
41 if (status != 0)
42 {
43 (*info->memory_error_func) (status, memaddr, info);
44 return -1;
45 }
46
47 /* Cast the bytes into the insn (in a host-endian indep way). */
48 insn.i[0] = (buffer[0] << 24) & 0xff000000;
49 insn.i[0] |= (buffer[1] << 16) & 0xff0000;
50 insn.i[0] |= (buffer[2] << 8) & 0xff00;
51 insn.i[0] |= buffer[3] & 0xff;
52 insn.i[1] = (buffer[4] << 24) & 0xff000000;
53 insn.i[1] |= (buffer[5] << 16) & 0xff0000;
54
55 /* Find the first match in the opcode table. We could speed this up
56 a bit by doing a binary search on the major opcode. */
57 opcode_end = i370_opcodes + i370_num_opcodes;
58 for (opcode = i370_opcodes; opcode < opcode_end; opcode++)
59 {
60 const unsigned char *opindex;
61 const struct i370_operand *operand;
62 i370_insn_t masked;
63 int invalid;
64
65 /* Mask off operands, and look for a match ... */
66 masked = insn;
67 if (2 == opcode->len)
68 {
69 masked.i[0] >>= 16;
70 masked.i[0] &= 0xffff;
71 }
72 masked.i[0] &= opcode->mask.i[0];
73 if (masked.i[0] != opcode->opcode.i[0])
74 continue;
75
76 if (6 == opcode->len)
77 {
78 masked.i[1] &= opcode->mask.i[1];
79 if (masked.i[1] != opcode->opcode.i[1])
80 continue;
81 }
82
83 /* Found a match. adjust a tad. */
84 if (2 == opcode->len)
85 {
86 insn.i[0] >>= 16;
87 insn.i[0] &= 0xffff;
88 }
89
90 /* Make two passes over the operands. First see if any of them
91 have extraction functions, and, if they do, make sure the
92 instruction is valid. */
93 invalid = 0;
94 for (opindex = opcode->operands; *opindex != 0; opindex++)
95 {
96 operand = i370_operands + *opindex;
97 if (operand->extract)
98 (*operand->extract) (insn, &invalid);
99 }
100 if (invalid)
101 continue;
102
103 /* The instruction is valid. */
104 (*info->fprintf_func) (info->stream, "%s", opcode->name);
105 if (opcode->operands[0] != 0)
106 (*info->fprintf_func) (info->stream, "\t");
107
108 /* Now extract and print the operands. */
109 for (opindex = opcode->operands; *opindex != 0; opindex++)
110 {
111 long value;
112
113 operand = i370_operands + *opindex;
114
115 /* Extract the value from the instruction. */
116 if (operand->extract)
117 value = (*operand->extract) (insn, (int *) NULL);
118 else
119 value = (insn.i[0] >> operand->shift) & ((1 << operand->bits) - 1);
120
121 /* Print the operand as directed by the flags. */
122 if ((operand->flags & I370_OPERAND_OPTIONAL) != 0)
123 {
124 if (value)
125 (*info->fprintf_func) (info->stream, "(r%ld)", value);
126 }
127 else if ((operand->flags & I370_OPERAND_SBASE) != 0)
128 {
129 (*info->fprintf_func) (info->stream, "(r%ld)", value);
130 }
131 else if ((operand->flags & I370_OPERAND_INDEX) != 0)
132 {
133 if (value)
134 (*info->fprintf_func) (info->stream, "(r%ld,", value);
135 else
136 (*info->fprintf_func) (info->stream, "(,");
137 }
138 else if ((operand->flags & I370_OPERAND_LENGTH) != 0)
139 {
140 (*info->fprintf_func) (info->stream, "(%ld,", value);
141 }
142 else if ((operand->flags & I370_OPERAND_BASE) != 0)
143 (*info->fprintf_func) (info->stream, "r%ld)", value);
144 else if ((operand->flags & I370_OPERAND_GPR) != 0)
145 (*info->fprintf_func) (info->stream, "r%ld,", value);
146 else if ((operand->flags & I370_OPERAND_FPR) != 0)
147 (*info->fprintf_func) (info->stream, "f%ld,", value);
148 else if ((operand->flags & I370_OPERAND_RELATIVE) != 0)
149 (*info->fprintf_func) (info->stream, "%ld", value);
150 else
151 (*info->fprintf_func) (info->stream, " %ld, ", value);
152 }
153
154 return opcode->len;
155 }
156
157 /* We could not find a match. */
158 (*info->fprintf_func) (info->stream, ".short 0x%02x%02x", buffer[0], buffer[1]);
159
160 return 2;
161 }
162