xref: /openbmc/qemu/target/avr/disas.c (revision 235fe6d0)
1 /*
2  * AVR disassembler
3  *
4  * Copyright (c) 2019-2020 Richard Henderson <rth@twiddle.net>
5  * Copyright (c) 2019-2020 Michael Rolnik <mrolnik@gmail.com>
6  *
7  * This program is free software: you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation, either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * 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 program.  If not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "cpu.h"
23 
24 typedef struct {
25     disassemble_info *info;
26     uint16_t next_word;
27     bool next_word_used;
28 } DisasContext;
29 
30 static int to_regs_16_31_by_one(DisasContext *ctx, int indx)
31 {
32     return 16 + (indx % 16);
33 }
34 
35 static int to_regs_16_23_by_one(DisasContext *ctx, int indx)
36 {
37     return 16 + (indx % 8);
38 }
39 
40 static int to_regs_24_30_by_two(DisasContext *ctx, int indx)
41 {
42     return 24 + (indx % 4) * 2;
43 }
44 
45 static int to_regs_00_30_by_two(DisasContext *ctx, int indx)
46 {
47     return (indx % 16) * 2;
48 }
49 
50 static uint16_t next_word(DisasContext *ctx)
51 {
52     ctx->next_word_used = true;
53     return ctx->next_word;
54 }
55 
56 static int append_16(DisasContext *ctx, int x)
57 {
58     return x << 16 | next_word(ctx);
59 }
60 
61 /* Include the auto-generated decoder.  */
62 static bool decode_insn(DisasContext *ctx, uint16_t insn);
63 #include "decode-insn.c.inc"
64 
65 #define output(mnemonic, format, ...) \
66     (pctx->info->fprintf_func(pctx->info->stream, "%-9s " format, \
67                               mnemonic, ##__VA_ARGS__))
68 
69 int avr_print_insn(bfd_vma addr, disassemble_info *info)
70 {
71     DisasContext ctx;
72     DisasContext *pctx = &ctx;
73     bfd_byte buffer[4];
74     uint16_t insn;
75     int status;
76 
77     ctx.info = info;
78 
79     status = info->read_memory_func(addr, buffer, 4, info);
80     if (status != 0) {
81         info->memory_error_func(status, addr, info);
82         return -1;
83     }
84     insn = bfd_getl16(buffer);
85     ctx.next_word = bfd_getl16(buffer + 2);
86     ctx.next_word_used = false;
87 
88     if (!decode_insn(&ctx, insn)) {
89         output(".db", "0x%02x, 0x%02x", buffer[0], buffer[1]);
90     }
91 
92     return ctx.next_word_used ? 4 : 2;
93 }
94 
95 
96 #define INSN(opcode, format, ...)                                       \
97 static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a)        \
98 {                                                                       \
99     output(#opcode, format, ##__VA_ARGS__);                             \
100     return true;                                                        \
101 }
102 
103 #define INSN_MNEMONIC(opcode, mnemonic, format, ...)                    \
104 static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a)        \
105 {                                                                       \
106     output(mnemonic, format, ##__VA_ARGS__);                            \
107     return true;                                                        \
108 }
109 
110 /*
111  *   C       Z       N       V       S       H       T       I
112  *   0       1       2       3       4       5       6       7
113  */
114 static const char brbc[][5] = {
115     "BRCC", "BRNE", "BRPL", "BRVC", "BRGE", "BRHC", "BRTC", "BRID"
116 };
117 
118 static const char brbs[][5] = {
119     "BRCS", "BREQ", "BRMI", "BRVS", "BRLT", "BRHS", "BRTS", "BRIE"
120 };
121 
122 static const char bset[][4] = {
123     "SEC",  "SEZ",  "SEN",  "SEZ",  "SES",  "SEH",  "SET",  "SEI"
124 };
125 
126 static const char bclr[][4] = {
127     "CLC",  "CLZ",  "CLN",  "CLZ",  "CLS",  "CLH",  "CLT",  "CLI"
128 };
129 
130 /*
131  * Arithmetic Instructions
132  */
133 INSN(ADD,    "r%d, r%d", a->rd, a->rr)
134 INSN(ADC,    "r%d, r%d", a->rd, a->rr)
135 INSN(ADIW,   "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
136 INSN(SUB,    "r%d, r%d", a->rd, a->rr)
137 INSN(SUBI,   "r%d, %d", a->rd, a->imm)
138 INSN(SBC,    "r%d, r%d", a->rd, a->rr)
139 INSN(SBCI,   "r%d, %d", a->rd, a->imm)
140 INSN(SBIW,   "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
141 INSN(AND,    "r%d, r%d", a->rd, a->rr)
142 INSN(ANDI,   "r%d, %d", a->rd, a->imm)
143 INSN(OR,     "r%d, r%d", a->rd, a->rr)
144 INSN(ORI,    "r%d, %d", a->rd, a->imm)
145 INSN(EOR,    "r%d, r%d", a->rd, a->rr)
146 INSN(COM,    "r%d", a->rd)
147 INSN(NEG,    "r%d", a->rd)
148 INSN(INC,    "r%d", a->rd)
149 INSN(DEC,    "r%d", a->rd)
150 INSN(MUL,    "r%d, r%d", a->rd, a->rr)
151 INSN(MULS,   "r%d, r%d", a->rd, a->rr)
152 INSN(MULSU,  "r%d, r%d", a->rd, a->rr)
153 INSN(FMUL,   "r%d, r%d", a->rd, a->rr)
154 INSN(FMULS,  "r%d, r%d", a->rd, a->rr)
155 INSN(FMULSU, "r%d, r%d", a->rd, a->rr)
156 INSN(DES,    "%d", a->imm)
157 
158 /*
159  * Branch Instructions
160  */
161 INSN(RJMP,   ".%+d", a->imm * 2)
162 INSN(IJMP,   "")
163 INSN(EIJMP,  "")
164 INSN(JMP,    "0x%x", a->imm * 2)
165 INSN(RCALL,  ".%+d", a->imm * 2)
166 INSN(ICALL,  "")
167 INSN(EICALL, "")
168 INSN(CALL,   "0x%x", a->imm * 2)
169 INSN(RET,    "")
170 INSN(RETI,   "")
171 INSN(CPSE,   "r%d, r%d", a->rd, a->rr)
172 INSN(CP,     "r%d, r%d", a->rd, a->rr)
173 INSN(CPC,    "r%d, r%d", a->rd, a->rr)
174 INSN(CPI,    "r%d, %d", a->rd, a->imm)
175 INSN(SBRC,   "r%d, %d", a->rr, a->bit)
176 INSN(SBRS,   "r%d, %d", a->rr, a->bit)
177 INSN(SBIC,   "$%d, %d", a->reg, a->bit)
178 INSN(SBIS,   "$%d, %d", a->reg, a->bit)
179 INSN_MNEMONIC(BRBS,  brbs[a->bit], ".%+d", a->imm * 2)
180 INSN_MNEMONIC(BRBC,  brbc[a->bit], ".%+d", a->imm * 2)
181 
182 /*
183  * Data Transfer Instructions
184  */
185 INSN(MOV,    "r%d, r%d", a->rd, a->rr)
186 INSN(MOVW,   "r%d:r%d, r%d:r%d", a->rd + 1, a->rd, a->rr + 1, a->rr)
187 INSN(LDI,    "r%d, %d", a->rd, a->imm)
188 INSN(LDS,    "r%d, %d", a->rd, a->imm)
189 INSN(LDX1,   "r%d, X", a->rd)
190 INSN(LDX2,   "r%d, X+", a->rd)
191 INSN(LDX3,   "r%d, -X", a->rd)
192 INSN(LDY2,   "r%d, Y+", a->rd)
193 INSN(LDY3,   "r%d, -Y", a->rd)
194 INSN(LDZ2,   "r%d, Z+", a->rd)
195 INSN(LDZ3,   "r%d, -Z", a->rd)
196 INSN(LDDY,   "r%d, Y+%d", a->rd, a->imm)
197 INSN(LDDZ,   "r%d, Z+%d", a->rd, a->imm)
198 INSN(STS,    "%d, r%d", a->imm, a->rd)
199 INSN(STX1,   "X, r%d", a->rr)
200 INSN(STX2,   "X+, r%d", a->rr)
201 INSN(STX3,   "-X, r%d", a->rr)
202 INSN(STY2,   "Y+, r%d", a->rd)
203 INSN(STY3,   "-Y, r%d", a->rd)
204 INSN(STZ2,   "Z+, r%d", a->rd)
205 INSN(STZ3,   "-Z, r%d", a->rd)
206 INSN(STDY,   "Y+%d, r%d", a->imm, a->rd)
207 INSN(STDZ,   "Z+%d, r%d", a->imm, a->rd)
208 INSN(LPM1,   "")
209 INSN(LPM2,   "r%d, Z", a->rd)
210 INSN(LPMX,   "r%d, Z+", a->rd)
211 INSN(ELPM1,  "")
212 INSN(ELPM2,  "r%d, Z", a->rd)
213 INSN(ELPMX,  "r%d, Z+", a->rd)
214 INSN(SPM,    "")
215 INSN(SPMX,   "Z+")
216 INSN(IN,     "r%d, $%d", a->rd, a->imm)
217 INSN(OUT,    "$%d, r%d", a->imm, a->rd)
218 INSN(PUSH,   "r%d", a->rd)
219 INSN(POP,    "r%d", a->rd)
220 INSN(XCH,    "Z, r%d", a->rd)
221 INSN(LAC,    "Z, r%d", a->rd)
222 INSN(LAS,    "Z, r%d", a->rd)
223 INSN(LAT,    "Z, r%d", a->rd)
224 
225 /*
226  * Bit and Bit-test Instructions
227  */
228 INSN(LSR,    "r%d", a->rd)
229 INSN(ROR,    "r%d", a->rd)
230 INSN(ASR,    "r%d", a->rd)
231 INSN(SWAP,   "r%d", a->rd)
232 INSN(SBI,    "$%d, %d", a->reg, a->bit)
233 INSN(CBI,    "%d, %d", a->reg, a->bit)
234 INSN(BST,    "r%d, %d", a->rd, a->bit)
235 INSN(BLD,    "r%d, %d", a->rd, a->bit)
236 INSN_MNEMONIC(BSET,  bset[a->bit], "")
237 INSN_MNEMONIC(BCLR,  bclr[a->bit], "")
238 
239 /*
240  * MCU Control Instructions
241  */
242 INSN(BREAK,  "")
243 INSN(NOP,    "")
244 INSN(SLEEP,  "")
245 INSN(WDR,    "")
246