Mesen/SevenZip/BraIA64.c

70 lines
1.7 KiB
C

/* BraIA64.c -- Converter for IA-64 code
2013-11-12 : Igor Pavlov : Public domain */
#include "Precomp.h"
#include "Bra.h"
static const Byte kBranchTable[32] =
{
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
4, 4, 6, 6, 0, 0, 7, 7,
4, 4, 0, 0, 4, 4, 0, 0
};
SizeT IA64_Convert(Byte *data, SizeT size, UInt32 ip, int encoding)
{
SizeT i;
if (size < 16)
return 0;
size -= 16;
for (i = 0; i <= size; i += 16)
{
UInt32 instrTemplate = data[i] & 0x1F;
UInt32 mask = kBranchTable[instrTemplate];
UInt32 bitPos = 5;
int slot;
for (slot = 0; slot < 3; slot++, bitPos += 41)
{
UInt32 bytePos, bitRes;
UInt64 instruction, instNorm;
int j;
if (((mask >> slot) & 1) == 0)
continue;
bytePos = (bitPos >> 3);
bitRes = bitPos & 0x7;
instruction = 0;
for (j = 0; j < 6; j++)
instruction += (UInt64)data[i + j + bytePos] << (8 * j);
instNorm = instruction >> bitRes;
if (((instNorm >> 37) & 0xF) == 0x5 && ((instNorm >> 9) & 0x7) == 0)
{
UInt32 src = (UInt32)((instNorm >> 13) & 0xFFFFF);
UInt32 dest;
src |= ((UInt32)(instNorm >> 36) & 1) << 20;
src <<= 4;
if (encoding)
dest = ip + (UInt32)i + src;
else
dest = src - (ip + (UInt32)i);
dest >>= 4;
instNorm &= ~((UInt64)(0x8FFFFF) << 13);
instNorm |= ((UInt64)(dest & 0xFFFFF) << 13);
instNorm |= ((UInt64)(dest & 0x100000) << (36 - 20));
instruction &= (1 << bitRes) - 1;
instruction |= (instNorm << bitRes);
for (j = 0; j < 6; j++)
data[i + j + bytePos] = (Byte)(instruction >> (8 * j));
}
}
}
return i;
}