1 /* alpha-dis.c -- Disassemble Alpha AXP instructions
2 Copyright (C) 1996-2023 Free Software Foundation, Inc.
3 Contributed by Richard Henderson <rth@tamu.edu>,
4 patterned after the PPC opcode handling written by Ian Lance Taylor.
5
6 This file is part of libopcodes.
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, MA
21 02110-1301, USA. */
22
23 #include "sysdep.h"
24 #include <stdio.h>
25 #include "disassemble.h"
26 #include "opcode/alpha.h"
27
28 /* OSF register names. */
29
30 static const char * const osf_regnames[64] = {
31 "v0", "t0", "t1", "t2", "t3", "t4", "t5", "t6",
32 "t7", "s0", "s1", "s2", "s3", "s4", "s5", "fp",
33 "a0", "a1", "a2", "a3", "a4", "a5", "t8", "t9",
34 "t10", "t11", "ra", "t12", "at", "gp", "sp", "zero",
35 "$f0", "$f1", "$f2", "$f3", "$f4", "$f5", "$f6", "$f7",
36 "$f8", "$f9", "$f10", "$f11", "$f12", "$f13", "$f14", "$f15",
37 "$f16", "$f17", "$f18", "$f19", "$f20", "$f21", "$f22", "$f23",
38 "$f24", "$f25", "$f26", "$f27", "$f28", "$f29", "$f30", "$f31"
39 };
40
41 /* VMS register names. */
42
43 static const char * const vms_regnames[64] = {
44 "R0", "R1", "R2", "R3", "R4", "R5", "R6", "R7",
45 "R8", "R9", "R10", "R11", "R12", "R13", "R14", "R15",
46 "R16", "R17", "R18", "R19", "R20", "R21", "R22", "R23",
47 "R24", "AI", "RA", "PV", "AT", "FP", "SP", "RZ",
48 "F0", "F1", "F2", "F3", "F4", "F5", "F6", "F7",
49 "F8", "F9", "F10", "F11", "F12", "F13", "F14", "F15",
50 "F16", "F17", "F18", "F19", "F20", "F21", "F22", "F23",
51 "F24", "F25", "F26", "F27", "F28", "F29", "F30", "FZ"
52 };
53
54 /* Disassemble Alpha instructions. */
55
56 int
57 print_insn_alpha (bfd_vma memaddr, struct disassemble_info *info)
58 {
59 static const struct alpha_opcode *opcode_index[AXP_NOPS+1];
60 const char * const * regnames;
61 const struct alpha_opcode *opcode, *opcode_end;
62 const unsigned char *opindex;
63 unsigned insn, op, isa_mask;
64 int need_comma;
65
66 /* Initialize the majorop table the first time through */
67 if (!opcode_index[0])
68 {
69 opcode = alpha_opcodes;
70 opcode_end = opcode + alpha_num_opcodes;
71
72 for (op = 0; op < AXP_NOPS; ++op)
73 {
74 opcode_index[op] = opcode;
75 while (opcode < opcode_end && op == AXP_OP (opcode->opcode))
76 ++opcode;
77 }
78 opcode_index[op] = opcode;
79 }
80
81 if (info->flavour == bfd_target_evax_flavour)
82 regnames = vms_regnames;
83 else
84 regnames = osf_regnames;
85
86 isa_mask = AXP_OPCODE_NOPAL;
87 switch (info->mach)
88 {
89 case bfd_mach_alpha_ev4:
90 isa_mask |= AXP_OPCODE_EV4;
91 break;
92 case bfd_mach_alpha_ev5:
93 isa_mask |= AXP_OPCODE_EV5;
94 break;
95 case bfd_mach_alpha_ev6:
96 isa_mask |= AXP_OPCODE_EV6;
97 break;
98 }
99
100 /* Read the insn into a host word */
101 {
102 bfd_byte buffer[4];
103 int status = (*info->read_memory_func) (memaddr, buffer, 4, info);
104 if (status != 0)
105 {
106 (*info->memory_error_func) (status, memaddr, info);
107 return -1;
108 }
109 insn = bfd_getl32 (buffer);
110 }
111
112 /* Get the major opcode of the instruction. */
113 op = AXP_OP (insn);
114
115 /* Find the first match in the opcode table. */
116 opcode_end = opcode_index[op + 1];
117 for (opcode = opcode_index[op]; opcode < opcode_end; ++opcode)
118 {
119 if ((insn ^ opcode->opcode) & opcode->mask)
120 continue;
121
122 if (!(opcode->flags & isa_mask))
123 continue;
124
125 /* Make two passes over the operands. First see if any of them
126 have extraction functions, and, if they do, make sure the
127 instruction is valid. */
128 {
129 int invalid = 0;
130 for (opindex = opcode->operands; *opindex != 0; opindex++)
131 {
132 const struct alpha_operand *operand = alpha_operands + *opindex;
133 if (operand->extract)
134 (*operand->extract) (insn, &invalid);
135 }
136 if (invalid)
137 continue;
138 }
139
140 /* The instruction is valid. */
141 goto found;
142 }
143
144 /* No instruction found */
145 (*info->fprintf_func) (info->stream, ".long %#08x", insn);
146
147 return 4;
148
149 found:
150 (*info->fprintf_func) (info->stream, "%s", opcode->name);
151 if (opcode->operands[0] != 0)
152 (*info->fprintf_func) (info->stream, "\t");
153
154 /* Now extract and print the operands. */
155 need_comma = 0;
156 for (opindex = opcode->operands; *opindex != 0; opindex++)
157 {
158 const struct alpha_operand *operand = alpha_operands + *opindex;
159 int value;
160
161 /* Operands that are marked FAKE are simply ignored. We
162 already made sure that the extract function considered
163 the instruction to be valid. */
164 if ((operand->flags & AXP_OPERAND_FAKE) != 0)
165 continue;
166
167 /* Extract the value from the instruction. */
168 if (operand->extract)
169 value = (*operand->extract) (insn, (int *) NULL);
170 else
171 {
172 value = (insn >> operand->shift) & ((1 << operand->bits) - 1);
173 if (operand->flags & AXP_OPERAND_SIGNED)
174 {
175 int signbit = 1 << (operand->bits - 1);
176 value = (value ^ signbit) - signbit;
177 }
178 }
179
180 if (need_comma &&
181 ((operand->flags & (AXP_OPERAND_PARENS | AXP_OPERAND_COMMA))
182 != AXP_OPERAND_PARENS))
183 {
184 (*info->fprintf_func) (info->stream, ",");
185 }
186 if (operand->flags & AXP_OPERAND_PARENS)
187 (*info->fprintf_func) (info->stream, "(");
188
189 /* Print the operand as directed by the flags. */
190 if (operand->flags & AXP_OPERAND_IR)
191 (*info->fprintf_func) (info->stream, "%s", regnames[value]);
192 else if (operand->flags & AXP_OPERAND_FPR)
193 (*info->fprintf_func) (info->stream, "%s", regnames[value + 32]);
194 else if (operand->flags & AXP_OPERAND_RELATIVE)
195 (*info->print_address_func) (memaddr + 4 + value, info);
196 else if (operand->flags & AXP_OPERAND_SIGNED)
197 (*info->fprintf_func) (info->stream, "%d", value);
198 else
199 (*info->fprintf_func) (info->stream, "%#x", value);
200
201 if (operand->flags & AXP_OPERAND_PARENS)
202 (*info->fprintf_func) (info->stream, ")");
203 need_comma = 1;
204 }
205
206 return 4;
207 }