1 /* Bcj2Enc.c -- BCJ2 Encoder (Converter for x86 code) 2 2014-11-10 : Igor Pavlov : Public domain */ 3 4 #include "Precomp.h" 5 6 /* #define SHOW_STAT */ 7 8 #ifdef SHOW_STAT 9 #include <stdio.h> 10 #define PRF(x) x 11 #else 12 #define PRF(x) 13 #endif 14 15 #include <windows.h> 16 #include <string.h> 17 18 #include "Bcj2.h" 19 #include "CpuArch.h" 20 21 #define CProb UInt16 22 23 #define kTopValue ((UInt32)1 << 24) 24 #define kNumModelBits 11 25 #define kBitModelTotal (1 << kNumModelBits) 26 #define kNumMoveBits 5 27 28 void Bcj2Enc_Init(CBcj2Enc *p) 29 { 30 unsigned i; 31 32 p->state = BCJ2_ENC_STATE_OK; 33 p->finishMode = BCJ2_ENC_FINISH_MODE_CONTINUE; 34 35 p->prevByte = 0; 36 37 p->cache = 0; 38 p->range = 0xFFFFFFFF; 39 p->low = 0; 40 p->cacheSize = 1; 41 42 p->ip = 0; 43 44 p->fileIp = 0; 45 p->fileSize = 0; 46 p->relatLimit = BCJ2_RELAT_LIMIT; 47 48 p->tempPos = 0; 49 50 p->flushPos = 0; 51 52 for (i = 0; i < sizeof(p->probs) / sizeof(p->probs[0]); i++) 53 p->probs[i] = kBitModelTotal >> 1; 54 } 55 56 static Bool MY_FAST_CALL RangeEnc_ShiftLow(CBcj2Enc *p) 57 { 58 if ((UInt32)p->low < (UInt32)0xFF000000 || (UInt32)(p->low >> 32) != 0) 59 { 60 Byte *buf = p->bufs[BCJ2_STREAM_RC]; 61 do 62 { 63 if (buf == p->lims[BCJ2_STREAM_RC]) 64 { 65 p->state = BCJ2_STREAM_RC; 66 p->bufs[BCJ2_STREAM_RC] = buf; 67 return True; 68 } 69 *buf++ = (Byte)(p->cache + (Byte)(p->low >> 32)); 70 p->cache = 0xFF; 71 } 72 while (--p->cacheSize); 73 p->bufs[BCJ2_STREAM_RC] = buf; 74 p->cache = (Byte)((UInt32)p->low >> 24); 75 } 76 p->cacheSize++; 77 p->low = (UInt32)p->low << 8; 78 return False; 79 } 80 81 static void Bcj2Enc_Encode_2(CBcj2Enc *p) 82 { 83 if (BCJ2_IS_32BIT_STREAM(p->state)) 84 { 85 Byte *cur = p->bufs[p->state]; 86 if (cur == p->lims[p->state]) 87 return; 88 SetBe32(cur, p->tempTarget); 89 p->bufs[p->state] = cur + 4; 90 } 91 92 p->state = BCJ2_ENC_STATE_ORIG; 93 94 for (;;) 95 { 96 if (p->range < kTopValue) 97 { 98 if (RangeEnc_ShiftLow(p)) 99 return; 100 p->range <<= 8; 101 } 102 103 { 104 { 105 const Byte *src = p->src; 106 const Byte *srcLim; 107 Byte *dest; 108 SizeT num = p->srcLim - src; 109 110 if (p->finishMode == BCJ2_ENC_FINISH_MODE_CONTINUE) 111 { 112 if (num <= 4) 113 return; 114 num -= 4; 115 } 116 else if (num == 0) 117 break; 118 119 dest = p->bufs[BCJ2_STREAM_MAIN]; 120 if (num > (SizeT)(p->lims[BCJ2_STREAM_MAIN] - dest)) 121 { 122 num = p->lims[BCJ2_STREAM_MAIN] - dest; 123 if (num == 0) 124 { 125 p->state = BCJ2_STREAM_MAIN; 126 return; 127 } 128 } 129 130 srcLim = src + num; 131 132 if (p->prevByte == 0x0F && (src[0] & 0xF0) == 0x80) 133 *dest = src[0]; 134 else for (;;) 135 { 136 Byte b = *src; 137 *dest = b; 138 if (b != 0x0F) 139 { 140 if ((b & 0xFE) == 0xE8) 141 break; 142 dest++; 143 if (++src != srcLim) 144 continue; 145 break; 146 } 147 dest++; 148 if (++src == srcLim) 149 break; 150 if ((*src & 0xF0) != 0x80) 151 continue; 152 *dest = *src; 153 break; 154 } 155 156 num = src - p->src; 157 158 if (src == srcLim) 159 { 160 p->prevByte = src[-1]; 161 p->bufs[BCJ2_STREAM_MAIN] = dest; 162 p->src = src; 163 p->ip += (UInt32)num; 164 continue; 165 } 166 167 { 168 Byte context = (Byte)(num == 0 ? p->prevByte : src[-1]); 169 Bool needConvert; 170 171 p->bufs[BCJ2_STREAM_MAIN] = dest + 1; 172 p->ip += (UInt32)num + 1; 173 src++; 174 175 needConvert = False; 176 177 if ((SizeT)(p->srcLim - src) >= 4) 178 { 179 UInt32 relatVal = GetUi32(src); 180 if ((p->fileSize == 0 || (UInt32)(p->ip + 4 + relatVal - p->fileIp) < p->fileSize) 181 && ((relatVal + p->relatLimit) >> 1) < p->relatLimit) 182 needConvert = True; 183 } 184 185 { 186 UInt32 bound; 187 unsigned ttt; 188 Byte b = src[-1]; 189 CProb *prob = p->probs + (unsigned)(b == 0xE8 ? 2 + (unsigned)context : (b == 0xE9 ? 1 : 0)); 190 191 ttt = *prob; 192 bound = (p->range >> kNumModelBits) * ttt; 193 194 if (!needConvert) 195 { 196 p->range = bound; 197 *prob = (CProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits)); 198 p->src = src; 199 p->prevByte = b; 200 continue; 201 } 202 203 p->low += bound; 204 p->range -= bound; 205 *prob = (CProb)(ttt - (ttt >> kNumMoveBits)); 206 207 { 208 UInt32 relatVal = GetUi32(src); 209 UInt32 absVal; 210 p->ip += 4; 211 absVal = p->ip + relatVal; 212 p->prevByte = src[3]; 213 src += 4; 214 p->src = src; 215 { 216 unsigned cj = (b == 0xE8) ? BCJ2_STREAM_CALL : BCJ2_STREAM_JUMP; 217 Byte *cur = p->bufs[cj]; 218 if (cur == p->lims[cj]) 219 { 220 p->state = cj; 221 p->tempTarget = absVal; 222 return; 223 } 224 SetBe32(cur, absVal); 225 p->bufs[cj] = cur + 4; 226 } 227 } 228 } 229 } 230 } 231 } 232 } 233 234 if (p->finishMode != BCJ2_ENC_FINISH_MODE_END_STREAM) 235 return; 236 237 for (; p->flushPos < 5; p->flushPos++) 238 if (RangeEnc_ShiftLow(p)) 239 return; 240 p->state = BCJ2_ENC_STATE_OK; 241 } 242 243 244 void Bcj2Enc_Encode(CBcj2Enc *p) 245 { 246 PRF(printf("\n")); 247 PRF(printf("---- ip = %8d tempPos = %8d src = %8d\n", p->ip, p->tempPos, p->srcLim - p->src)); 248 249 if (p->tempPos != 0) 250 { 251 unsigned extra = 0; 252 253 for (;;) 254 { 255 const Byte *src = p->src; 256 const Byte *srcLim = p->srcLim; 257 unsigned finishMode = p->finishMode; 258 259 p->src = p->temp; 260 p->srcLim = p->temp + p->tempPos; 261 if (src != srcLim) 262 p->finishMode = BCJ2_ENC_FINISH_MODE_CONTINUE; 263 264 PRF(printf(" ip = %8d tempPos = %8d src = %8d\n", p->ip, p->tempPos, p->srcLim - p->src)); 265 266 Bcj2Enc_Encode_2(p); 267 268 { 269 unsigned num = (unsigned)(p->src - p->temp); 270 unsigned tempPos = p->tempPos - num; 271 unsigned i; 272 p->tempPos = tempPos; 273 for (i = 0; i < tempPos; i++) 274 p->temp[i] = p->temp[i + num]; 275 276 p->src = src; 277 p->srcLim = srcLim; 278 p->finishMode = finishMode; 279 280 if (p->state != BCJ2_ENC_STATE_ORIG || src == srcLim) 281 return; 282 283 if (extra >= tempPos) 284 { 285 p->src = src - tempPos; 286 p->tempPos = 0; 287 break; 288 } 289 290 p->temp[tempPos] = src[0]; 291 p->tempPos = tempPos + 1; 292 p->src = src + 1; 293 extra++; 294 } 295 } 296 } 297 298 PRF(printf("++++ ip = %8d tempPos = %8d src = %8d\n", p->ip, p->tempPos, p->srcLim - p->src)); 299 300 Bcj2Enc_Encode_2(p); 301 302 if (p->state == BCJ2_ENC_STATE_ORIG) 303 { 304 const Byte *src = p->src; 305 unsigned rem = (unsigned)(p->srcLim - src); 306 unsigned i; 307 for (i = 0; i < rem; i++) 308 p->temp[i] = src[i]; 309 p->tempPos = rem; 310 p->src = src + rem; 311 } 312 } 313
