0,0 → 1,82 |
/* Bra86.c -- Converter for x86 code (BCJ) |
2013-11-12 : Igor Pavlov : Public domain */ |
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#include "Precomp.h" |
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#include "Bra.h" |
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#define Test86MSByte(b) ((((b) + 1) & 0xFE) == 0) |
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SizeT x86_Convert(Byte *data, SizeT size, UInt32 ip, UInt32 *state, int encoding) |
{ |
SizeT pos = 0; |
UInt32 mask = *state & 7; |
if (size < 5) |
return 0; |
size -= 4; |
ip += 5; |
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for (;;) |
{ |
Byte *p = data + pos; |
const Byte *limit = data + size; |
for (; p < limit; p++) |
if ((*p & 0xFE) == 0xE8) |
break; |
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{ |
SizeT d = (SizeT)(p - data - pos); |
pos = (SizeT)(p - data); |
if (p >= limit) |
{ |
*state = (d > 2 ? 0 : mask >> (unsigned)d); |
return pos; |
} |
if (d > 2) |
mask = 0; |
else |
{ |
mask >>= (unsigned)d; |
if (mask != 0 && (mask > 4 || mask == 3 || Test86MSByte(p[(mask >> 1) + 1]))) |
{ |
mask = (mask >> 1) | 4; |
pos++; |
continue; |
} |
} |
} |
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if (Test86MSByte(p[4])) |
{ |
UInt32 v = ((UInt32)p[4] << 24) | ((UInt32)p[3] << 16) | ((UInt32)p[2] << 8) | ((UInt32)p[1]); |
UInt32 cur = ip + (UInt32)pos; |
pos += 5; |
if (encoding) |
v += cur; |
else |
v -= cur; |
if (mask != 0) |
{ |
unsigned sh = (mask & 6) << 2; |
if (Test86MSByte((Byte)(v >> sh))) |
{ |
v ^= (((UInt32)0x100 << sh) - 1); |
if (encoding) |
v += cur; |
else |
v -= cur; |
} |
mask = 0; |
} |
p[1] = (Byte)v; |
p[2] = (Byte)(v >> 8); |
p[3] = (Byte)(v >> 16); |
p[4] = (Byte)(0 - ((v >> 24) & 1)); |
} |
else |
{ |
mask = (mask >> 1) | 4; |
pos++; |
} |
} |
} |