1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <stdio.h> 30 #include <inttypes.h> 31 #include <string.h> 32 33 struct disasm_table_entry_t 34 { 35 uint32_t mask; 36 uint32_t value; 37 const char* instr_template; 38 }; 39 40 41 static disasm_table_entry_t disasm_table[] = 42 { 43 {0xff000000, 0x91000000, "add <xd|sp>, <xn|sp>, #<imm1>, <shift1>"}, 44 {0xff000000, 0xd1000000, "sub <xd|sp>, <xn|sp>, #<imm1>, <shift1>"}, 45 {0xff200000, 0x8b000000, "add <xd>, <xn>, <xm>, <shift2> #<amt1>"}, 46 {0xff200000, 0x0b000000, "add <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 47 {0xff200000, 0x4b000000, "sub <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 48 {0xff200000, 0x6b000000, "subs <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 49 {0xff200000, 0x0a000000, "and <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 50 {0xff200000, 0x2a000000, "orr <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 51 {0xff200000, 0x2a200000, "orn <wd>, <wn>, <wm>, <shift2> #<amt1>"}, 52 {0xff800000, 0x72800000, "movk <wd>, #<imm2>, lsl #<shift3>"}, 53 {0xff800000, 0x52800000, "movz <wd>, #<imm2>, lsl #<shift3>"}, 54 {0xff800000, 0xd2800000, "movz <xd>, #<imm2>, lsl #<shift3>"}, 55 {0xffe00c00, 0x1a800000, "csel <wd>, <wn>, <wm>, <cond1>"}, 56 {0xffe00c00, 0x9a800000, "csel <xd>, <xn>, <xm>, <cond1>"}, 57 {0xffe00c00, 0x5a800000, "csinv <wd>, <wn>, <wm>, <cond1>"}, 58 {0xffe08000, 0x1b000000, "madd <wd>, <wn>, <wm>, <wa>"}, 59 {0xffe08000, 0x9b200000, "smaddl <xd>, <wn>, <wm>, <xa>"}, 60 {0xffe04c00, 0xb8604800, "ldr <wt>, [<xn|sp>, <r1><m1>, <ext1> #<amt2>]"}, 61 {0xffe04c00, 0xb8204800, "str <wt>, [<xn|sp>, <r1><m1>, <ext1> #<amt2>]"}, 62 {0xffe04c00, 0xf8604800, "ldr <xt>, [<xn|sp>, <r1><m1>, <ext1> #<amt3>]"}, 63 {0xffe04c00, 0xf8204800, "str <xt>, [<xn|sp>, <r1><m1>, <ext1> #<amt3>]"}, 64 {0xffe04c00, 0x38604800, "ldrb <wt>, [<xn|sp>, <r1><m1>, <ext1> <amt5>]"}, 65 {0xffe04c00, 0x38204800, "strb <wt>, [<xn|sp>, <r1><m1>, <ext1> <amt5>]"}, 66 {0xffe04c00, 0x78604800, "ldrh <wt>, [<xn|sp>, <r1><m1>, <ext1> #<amt6>]"}, 67 {0xffe04c00, 0x78204800, "strh <wt>, [<xn|sp>, <r1><m1>, <ext1> #<amt6>]"}, 68 {0xffe00c00, 0xb8400400, "ldr <wt>, [<xn|sp>], #<simm1>"}, 69 {0xffe00c00, 0xb8000c00, "str <wt>, [<xn|sp>, #<simm1>]!"}, 70 {0xffc00000, 0x13000000, "sbfm <wd>, <wn>, #<immr1>, #<imms1>"}, 71 {0xffc00000, 0x53000000, "ubfm <wd>, <wn>, #<immr1>, #<imms1>"}, 72 {0xffc00000, 0xd3400000, "ubfm <xd>, <xn>, #<immr1>, #<imms1>"}, 73 {0xffe00000, 0x13800000, "extr <wd>, <wn>, <wm>, #<lsb1>"}, 74 {0xff000000, 0x54000000, "b.<cond2> <label1>"}, 75 {0xfffffc1f, 0xd65f0000, "ret <xn>"}, 76 {0xffe00000, 0x8b200000, "add <xd|sp>, <xn|sp>, <r2><m1>, <ext2> #<amt4>"}, 77 {0xffe00000, 0xcb200000, "sub <xd|sp>, <xn|sp>, <r2><m1>, <ext2> #<amt4>"} 78 }; 79 80 static int32_t bits_signed(uint32_t instr, uint32_t msb, uint32_t lsb) 81 { 82 int32_t value; 83 value = ((int32_t)instr) << (31 - msb); 84 value >>= (31 - msb); 85 value >>= lsb; 86 return value; 87 } 88 static uint32_t bits_unsigned(uint32_t instr, uint32_t msb, uint32_t lsb) 89 { 90 uint32_t width = msb - lsb + 1; 91 uint32_t mask = (1 << width) - 1; 92 return ((instr >> lsb) & mask); 93 } 94 95 static void get_token(const char *instr, uint32_t index, char *token) 96 { 97 uint32_t i, j; 98 for(i = index, j = 0; i < strlen(instr); ++i) 99 { 100 if(instr[index] == '<' && instr[i] == '>') 101 { 102 token[j++] = instr[i]; 103 break; 104 } 105 else if(instr[index] != '<' && instr[i] == '<') 106 { 107 break; 108 } 109 else 110 { 111 token[j++] = instr[i]; 112 } 113 } 114 token[j] = '\0'; 115 return; 116 } 117 118 119 static const char * token_cc_table[] = 120 { 121 "eq", "ne", "cs", "cc", "mi", 122 "pl", "vs", "vc", "hi", "ls", 123 "ge", "lt", "gt", "le", "al", "nv" 124 }; 125 126 static void decode_rx_zr_token(uint32_t reg, const char *prefix, char *instr_part) 127 { 128 if(reg == 31) 129 sprintf(instr_part, "%s%s", prefix, "zr"); 130 else 131 sprintf(instr_part, "%s%d", prefix, reg); 132 } 133 134 static void decode_token(uint32_t code, char *token, char *instr_part) 135 { 136 if(strcmp(token, "<imm1>") == 0) 137 sprintf(instr_part, "0x%x", bits_unsigned(code, 21,10)); 138 else if(strcmp(token, "<imm2>") == 0) 139 sprintf(instr_part, "0x%x", bits_unsigned(code, 20,5)); 140 else if(strcmp(token, "<shift1>") == 0) 141 sprintf(instr_part, "lsl #%d", bits_unsigned(code, 23,22) * 12); 142 else if(strcmp(token, "<shift2>") == 0) 143 { 144 static const char * shift2_table[] = { "lsl", "lsr", "asr", "ror"}; 145 sprintf(instr_part, "%s", shift2_table[bits_unsigned(code, 23,22)]); 146 } 147 else if(strcmp(token, "<shift3>") == 0) 148 sprintf(instr_part, "%d", bits_unsigned(code, 22,21) * 16); 149 else if(strcmp(token, "<amt1>") == 0) 150 sprintf(instr_part, "%d", bits_unsigned(code, 15,10)); 151 else if(strcmp(token, "<amt2>") == 0) 152 sprintf(instr_part, "%d", bits_unsigned(code, 12,12) * 2); 153 else if(strcmp(token, "<amt3>") == 0) 154 sprintf(instr_part, "%d", bits_unsigned(code, 12,12) * 3); 155 else if(strcmp(token, "<amt4>") == 0) 156 sprintf(instr_part, "%d", bits_unsigned(code, 12,10)); 157 else if(strcmp(token, "<amt5>") == 0) 158 { 159 static const char * amt5_table[] = {"", "#0"}; 160 sprintf(instr_part, "%s", amt5_table[bits_unsigned(code, 12,12)]); 161 } 162 else if(strcmp(token, "<amt6>") == 0) 163 sprintf(instr_part, "%d", bits_unsigned(code, 12,12)); 164 else if(strcmp(token, "<simm1>") == 0) 165 sprintf(instr_part, "%d", bits_signed(code, 20,12)); 166 else if(strcmp(token, "<immr1>") == 0) 167 sprintf(instr_part, "%d", bits_unsigned(code, 21,16)); 168 else if(strcmp(token, "<imms1>") == 0) 169 sprintf(instr_part, "%d", bits_unsigned(code, 15,10)); 170 else if(strcmp(token, "<lsb1>") == 0) 171 sprintf(instr_part, "%d", bits_unsigned(code, 15,10)); 172 else if(strcmp(token, "<cond1>") == 0) 173 sprintf(instr_part, "%s", token_cc_table[bits_unsigned(code, 15,12)]); 174 else if(strcmp(token, "<cond2>") == 0) 175 sprintf(instr_part, "%s", token_cc_table[bits_unsigned(code, 4,0)]); 176 else if(strcmp(token, "<r1>") == 0) 177 { 178 const char * token_r1_table[] = 179 { 180 "reserved", "reserved", "w", "x", 181 "reserved", "reserved", "w", "x" 182 }; 183 sprintf(instr_part, "%s", token_r1_table[bits_unsigned(code, 15,13)]); 184 } 185 else if(strcmp(token, "<r2>") == 0) 186 { 187 static const char * token_r2_table[] = 188 { 189 "w","w","w", "x", "w", "w", "w", "x" 190 }; 191 sprintf(instr_part, "%s", token_r2_table[bits_unsigned(code, 15,13)]); 192 } 193 else if(strcmp(token, "<m1>") == 0) 194 { 195 uint32_t reg = bits_unsigned(code, 20,16); 196 if(reg == 31) 197 sprintf(instr_part, "%s", "zr"); 198 else 199 sprintf(instr_part, "%d", reg); 200 } 201 else if(strcmp(token, "<ext1>") == 0) 202 { 203 static const char * token_ext1_table[] = 204 { 205 "reserved","reserved","uxtw", "lsl", 206 "reserved","reserved", "sxtw", "sxtx" 207 }; 208 sprintf(instr_part, "%s", token_ext1_table[bits_unsigned(code, 15,13)]); 209 } 210 else if(strcmp(token, "<ext2>") == 0) 211 { 212 static const char * token_ext2_table[] = 213 { 214 "uxtb","uxth","uxtw","uxtx", 215 "sxtb","sxth","sxtw","sxtx" 216 }; 217 sprintf(instr_part, "%s", token_ext2_table[bits_unsigned(code, 15,13)]); 218 } 219 else if (strcmp(token, "<label1>") == 0) 220 { 221 int32_t offset = bits_signed(code, 23,5) * 4; 222 if(offset > 0) 223 sprintf(instr_part, "#.+%d", offset); 224 else 225 sprintf(instr_part, "#.-%d", -offset); 226 } 227 else if (strcmp(token, "<xn|sp>") == 0) 228 { 229 uint32_t reg = bits_unsigned(code, 9, 5); 230 if(reg == 31) 231 sprintf(instr_part, "%s", "sp"); 232 else 233 sprintf(instr_part, "x%d", reg); 234 } 235 else if (strcmp(token, "<xd|sp>") == 0) 236 { 237 uint32_t reg = bits_unsigned(code, 4, 0); 238 if(reg == 31) 239 sprintf(instr_part, "%s", "sp"); 240 else 241 sprintf(instr_part, "x%d", reg); 242 } 243 else if (strcmp(token, "<xn>") == 0) 244 decode_rx_zr_token(bits_unsigned(code, 9, 5), "x", instr_part); 245 else if (strcmp(token, "<xd>") == 0) 246 decode_rx_zr_token(bits_unsigned(code, 4, 0), "x", instr_part); 247 else if (strcmp(token, "<xm>") == 0) 248 decode_rx_zr_token(bits_unsigned(code, 20, 16), "x", instr_part); 249 else if (strcmp(token, "<xa>") == 0) 250 decode_rx_zr_token(bits_unsigned(code, 14, 10), "x", instr_part); 251 else if (strcmp(token, "<xt>") == 0) 252 decode_rx_zr_token(bits_unsigned(code, 4, 0), "x", instr_part); 253 else if (strcmp(token, "<wn>") == 0) 254 decode_rx_zr_token(bits_unsigned(code, 9, 5), "w", instr_part); 255 else if (strcmp(token, "<wd>") == 0) 256 decode_rx_zr_token(bits_unsigned(code, 4, 0), "w", instr_part); 257 else if (strcmp(token, "<wm>") == 0) 258 decode_rx_zr_token(bits_unsigned(code, 20, 16), "w", instr_part); 259 else if (strcmp(token, "<wa>") == 0) 260 decode_rx_zr_token(bits_unsigned(code, 14, 10), "w", instr_part); 261 else if (strcmp(token, "<wt>") == 0) 262 decode_rx_zr_token(bits_unsigned(code, 4, 0), "w", instr_part); 263 else 264 { 265 sprintf(instr_part, "error"); 266 } 267 return; 268 } 269 270 int arm64_disassemble(uint32_t code, char* instr) 271 { 272 uint32_t i; 273 char token[256]; 274 char instr_part[256]; 275 276 if(instr == NULL) 277 return -1; 278 279 bool matched = false; 280 disasm_table_entry_t *entry = NULL; 281 for(i = 0; i < sizeof(disasm_table)/sizeof(disasm_table_entry_t); ++i) 282 { 283 entry = &disasm_table[i]; 284 if((code & entry->mask) == entry->value) 285 { 286 matched = true; 287 break; 288 } 289 } 290 if(matched == false) 291 { 292 strcpy(instr, "Unknown Instruction"); 293 return -1; 294 } 295 else 296 { 297 uint32_t index = 0; 298 uint32_t length = strlen(entry->instr_template); 299 instr[0] = '\0'; 300 do 301 { 302 get_token(entry->instr_template, index, token); 303 if(token[0] == '<') 304 { 305 decode_token(code, token, instr_part); 306 strcat(instr, instr_part); 307 } 308 else 309 { 310 strcat(instr, token); 311 } 312 index += strlen(token); 313 }while(index < length); 314 return 0; 315 } 316 } 317
