1 /* i370-dis.c -- Disassemble Instruction 370 (ESA/390) instructions
2 Copyright (C) 1994-2016 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 the GNU opcodes library.
7
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)
11 any later version.
12
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.
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 "sysdep.h"
24 #include <stdio.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