1// BranchX86_2.c 2 3#include "BranchX86_2.h" 4 5#include "../../Alloc.h" 6 7#ifdef _LZMA_PROB32 8#define CProb UInt32 9#else 10#define CProb UInt16 11#endif 12 13#define IsJcc(b0, b1) ((b0) == 0x0F && ((b1) & 0xF0) == 0x80) 14#define IsJ(b0, b1) ((b1 & 0xFE) == 0xE8 || IsJcc(b0, b1)) 15 16#define kNumTopBits 24 17#define kTopValue ((UInt32)1 << kNumTopBits) 18 19#define kNumBitModelTotalBits 11 20#define kBitModelTotal (1 << kNumBitModelTotalBits) 21#define kNumMoveBits 5 22 23#define RC_READ_BYTE (*Buffer++) 24 25#define RC_INIT2 Code = 0; Range = 0xFFFFFFFF; \ 26 { int i; for(i = 0; i < 5; i++) { RC_TEST; Code = (Code << 8) | RC_READ_BYTE; }} 27 28#define RC_TEST { if (Buffer == BufferLim) return BCJ2_RESULT_DATA_ERROR; } 29 30#define RC_INIT(buffer, bufferSize) Buffer = buffer; BufferLim = buffer + bufferSize; RC_INIT2 31 32#define RC_NORMALIZE if (Range < kTopValue) { RC_TEST; Range <<= 8; Code = (Code << 8) | RC_READ_BYTE; } 33 34#define IfBit0(p) RC_NORMALIZE; bound = (Range >> kNumBitModelTotalBits) * *(p); if (Code < bound) 35#define UpdateBit0(p) Range = bound; *(p) += (kBitModelTotal - *(p)) >> kNumMoveBits; 36#define UpdateBit1(p) Range -= bound; Code -= bound; *(p) -= (*(p)) >> kNumMoveBits; 37// #define UpdateBit0(p) Range = bound; *(p) = (CProb)(*(p) + ((kBitModelTotal - *(p)) >> kNumMoveBits)); 38// #define UpdateBit1(p) Range -= bound; Code -= bound; *(p) = (CProb)(*(p) - (*(p) >> kNumMoveBits)); 39 40int x86_2_Decode( 41 const Byte *buf0, SizeT size0, 42 const Byte *buf1, SizeT size1, 43 const Byte *buf2, SizeT size2, 44 const Byte *buf3, SizeT size3, 45 Byte *outBuf, SizeT outSize) 46{ 47 CProb p[256 + 2]; 48 SizeT inPos = 0, outPos = 0; 49 50 const Byte *Buffer, *BufferLim; 51 UInt32 Range, Code; 52 Byte prevByte = 0; 53 54 unsigned int i; 55 for (i = 0; i < sizeof(p) / sizeof(p[0]); i++) 56 p[i] = kBitModelTotal >> 1; 57 RC_INIT(buf3, size3); 58 59 if (outSize == 0) 60 return BCJ2_RESULT_OK; 61 62 for (;;) 63 { 64 Byte b; 65 CProb *prob; 66 UInt32 bound; 67 68 SizeT limit = size0 - inPos; 69 if (outSize - outPos < limit) 70 limit = outSize - outPos; 71 while (limit != 0) 72 { 73 Byte b = buf0[inPos]; 74 outBuf[outPos++] = b; 75 if (IsJ(prevByte, b)) 76 break; 77 inPos++; 78 prevByte = b; 79 limit--; 80 } 81 82 if (limit == 0 || outPos == outSize) 83 break; 84 85 b = buf0[inPos++]; 86 87 if (b == 0xE8) 88 prob = p + prevByte; 89 else if (b == 0xE9) 90 prob = p + 256; 91 else 92 prob = p + 257; 93 94 IfBit0(prob) 95 { 96 UpdateBit0(prob) 97 prevByte = b; 98 } 99 else 100 { 101 UInt32 dest; 102 const Byte *v; 103 UpdateBit1(prob) 104 if (b == 0xE8) 105 { 106 v = buf1; 107 if (size1 < 4) 108 return BCJ2_RESULT_DATA_ERROR; 109 buf1 += 4; 110 size1 -= 4; 111 } 112 else 113 { 114 v = buf2; 115 if (size2 < 4) 116 return BCJ2_RESULT_DATA_ERROR; 117 buf2 += 4; 118 size2 -= 4; 119 } 120 dest = (((UInt32)v[0] << 24) | ((UInt32)v[1] << 16) | 121 ((UInt32)v[2] << 8) | ((UInt32)v[3])) - ((UInt32)outPos + 4); 122 outBuf[outPos++] = (Byte)dest; 123 if (outPos == outSize) 124 break; 125 outBuf[outPos++] = (Byte)(dest >> 8); 126 if (outPos == outSize) 127 break; 128 outBuf[outPos++] = (Byte)(dest >> 16); 129 if (outPos == outSize) 130 break; 131 outBuf[outPos++] = prevByte = (Byte)(dest >> 24); 132 } 133 } 134 return (outPos == outSize) ? BCJ2_RESULT_OK : BCJ2_RESULT_DATA_ERROR; 135} 136