1 /* ppc-dis.c -- Disassemble PowerPC instructions
2 Copyright 1994 Free Software Foundation, Inc.
3 Written by Ian Lance Taylor, Cygnus Support
4
5 This file is part of GDB, GAS, and the GNU binutils.
6
7 GDB, GAS, and the GNU binutils are free software; you can redistribute
8 them and/or modify them under the terms of the GNU General Public
9 License as published by the Free Software Foundation; either version
10 2, or (at your option) any later version.
11
12 GDB, GAS, and the GNU binutils are distributed in the hope that they
13 will be useful, but WITHOUT ANY WARRANTY; without even the implied
14 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 the GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this file; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 #include "nonstdio.h"
22 #include "ansidecl.h"
23 #include "ppc.h"
24
25 static int print_insn_powerpc PARAMS ((FILE *, unsigned long insn,
26 unsigned long memaddr, int dialect));
27
28 extern void print_address PARAMS((unsigned long memaddr));
29
30 /* Print a big endian PowerPC instruction. For convenience, also
31 disassemble instructions supported by the Motorola PowerPC 601. */
32
33 int
print_insn_big_powerpc(FILE * out,unsigned long insn,unsigned long memaddr)34 print_insn_big_powerpc (FILE *out, unsigned long insn, unsigned long memaddr)
35 {
36 return print_insn_powerpc (out, insn, memaddr,
37 PPC_OPCODE_PPC | PPC_OPCODE_601);
38 }
39
40 /* Print a PowerPC or POWER instruction. */
41
42 static int
print_insn_powerpc(FILE * out,unsigned long insn,unsigned long memaddr,int dialect)43 print_insn_powerpc (FILE *out, unsigned long insn, unsigned long memaddr,
44 int dialect)
45 {
46 const struct powerpc_opcode *opcode;
47 const struct powerpc_opcode *opcode_end;
48 unsigned long op;
49
50 /* Get the major opcode of the instruction. */
51 op = PPC_OP (insn);
52
53 /* Find the first match in the opcode table. We could speed this up
54 a bit by doing a binary search on the major opcode. */
55 opcode_end = powerpc_opcodes + powerpc_num_opcodes;
56 for (opcode = powerpc_opcodes; opcode < opcode_end; opcode++)
57 {
58 unsigned long table_op;
59 const unsigned char *opindex;
60 const struct powerpc_operand *operand;
61 int invalid;
62 int need_comma;
63 int need_paren;
64
65 table_op = PPC_OP (opcode->opcode);
66 if (op < table_op)
67 break;
68 if (op > table_op)
69 continue;
70
71 if ((insn & opcode->mask) != opcode->opcode
72 || (opcode->flags & dialect) == 0)
73 continue;
74
75 /* Make two passes over the operands. First see if any of them
76 have extraction functions, and, if they do, make sure the
77 instruction is valid. */
78 invalid = 0;
79 for (opindex = opcode->operands; *opindex != 0; opindex++)
80 {
81 operand = powerpc_operands + *opindex;
82 if (operand->extract)
83 (*operand->extract) (insn, &invalid);
84 }
85 if (invalid)
86 continue;
87
88 /* The instruction is valid. */
89 fprintf(out, "%s", opcode->name);
90 if (opcode->operands[0] != 0)
91 fprintf(out, "\t");
92
93 /* Now extract and print the operands. */
94 need_comma = 0;
95 need_paren = 0;
96 for (opindex = opcode->operands; *opindex != 0; opindex++)
97 {
98 long value;
99
100 operand = powerpc_operands + *opindex;
101
102 /* Operands that are marked FAKE are simply ignored. We
103 already made sure that the extract function considered
104 the instruction to be valid. */
105 if ((operand->flags & PPC_OPERAND_FAKE) != 0)
106 continue;
107
108 /* Extract the value from the instruction. */
109 if (operand->extract)
110 value = (*operand->extract) (insn, (int *) 0);
111 else
112 {
113 value = (insn >> operand->shift) & ((1 << operand->bits) - 1);
114 if ((operand->flags & PPC_OPERAND_SIGNED) != 0
115 && (value & (1 << (operand->bits - 1))) != 0)
116 value -= 1 << operand->bits;
117 }
118
119 /* If the operand is optional, and the value is zero, don't
120 print anything. */
121 if ((operand->flags & PPC_OPERAND_OPTIONAL) != 0
122 && (operand->flags & PPC_OPERAND_NEXT) == 0
123 && value == 0)
124 continue;
125
126 if (need_comma)
127 {
128 fprintf(out, ",");
129 need_comma = 0;
130 }
131
132 /* Print the operand as directed by the flags. */
133 if ((operand->flags & PPC_OPERAND_GPR) != 0)
134 fprintf(out, "r%ld", value);
135 else if ((operand->flags & PPC_OPERAND_FPR) != 0)
136 fprintf(out, "f%ld", value);
137 else if ((operand->flags & PPC_OPERAND_RELATIVE) != 0)
138 print_address (memaddr + value);
139 else if ((operand->flags & PPC_OPERAND_ABSOLUTE) != 0)
140 print_address (value & 0xffffffff);
141 else if ((operand->flags & PPC_OPERAND_CR) == 0
142 || (dialect & PPC_OPCODE_PPC) == 0)
143 fprintf(out, "%ld", value);
144 else
145 {
146 if (operand->bits == 3)
147 fprintf(out, "cr%d", value);
148 else
149 {
150 static const char *cbnames[4] = { "lt", "gt", "eq", "so" };
151 int cr;
152 int cc;
153
154 cr = value >> 2;
155 if (cr != 0)
156 fprintf(out, "4*cr%d", cr);
157 cc = value & 3;
158 if (cc != 0)
159 {
160 if (cr != 0)
161 fprintf(out, "+");
162 fprintf(out, "%s", cbnames[cc]);
163 }
164 }
165 }
166
167 if (need_paren)
168 {
169 fprintf(out, ")");
170 need_paren = 0;
171 }
172
173 if ((operand->flags & PPC_OPERAND_PARENS) == 0)
174 need_comma = 1;
175 else
176 {
177 fprintf(out, "(");
178 need_paren = 1;
179 }
180 }
181
182 /* We have found and printed an instruction; return. */
183 return 4;
184 }
185
186 /* We could not find a match. */
187 fprintf(out, ".long 0x%lx", insn);
188
189 return 4;
190 }
191