1 /* BraIA64.c -- Converter for IA-64 code
2 2013-11-12 : Igor Pavlov : Public domain */
3 
4 #include "Precomp.h"
5 
6 #include "Bra.h"
7 
8 static const Byte kBranchTable[32] =
9 {
10   0, 0, 0, 0, 0, 0, 0, 0,
11   0, 0, 0, 0, 0, 0, 0, 0,
12   4, 4, 6, 6, 0, 0, 7, 7,
13   4, 4, 0, 0, 4, 4, 0, 0
14 };
15 
IA64_Convert(Byte * data,SizeT size,UInt32 ip,int encoding)16 SizeT IA64_Convert(Byte *data, SizeT size, UInt32 ip, int encoding)
17 {
18   SizeT i;
19   if (size < 16)
20     return 0;
21   size -= 16;
22   for (i = 0; i <= size; i += 16)
23   {
24     UInt32 instrTemplate = data[i] & 0x1F;
25     UInt32 mask = kBranchTable[instrTemplate];
26     UInt32 bitPos = 5;
27     int slot;
28     for (slot = 0; slot < 3; slot++, bitPos += 41)
29     {
30       UInt32 bytePos, bitRes;
31       UInt64 instruction, instNorm;
32       int j;
33       if (((mask >> slot) & 1) == 0)
34         continue;
35       bytePos = (bitPos >> 3);
36       bitRes = bitPos & 0x7;
37       instruction = 0;
38       for (j = 0; j < 6; j++)
39         instruction += (UInt64)data[i + j + bytePos] << (8 * j);
40 
41       instNorm = instruction >> bitRes;
42       if (((instNorm >> 37) & 0xF) == 0x5 && ((instNorm >> 9) & 0x7) == 0)
43       {
44         UInt32 src = (UInt32)((instNorm >> 13) & 0xFFFFF);
45         UInt32 dest;
46         src |= ((UInt32)(instNorm >> 36) & 1) << 20;
47 
48         src <<= 4;
49 
50         if (encoding)
51           dest = ip + (UInt32)i + src;
52         else
53           dest = src - (ip + (UInt32)i);
54 
55         dest >>= 4;
56 
57         instNorm &= ~((UInt64)(0x8FFFFF) << 13);
58         instNorm |= ((UInt64)(dest & 0xFFFFF) << 13);
59         instNorm |= ((UInt64)(dest & 0x100000) << (36 - 20));
60 
61         instruction &= (1 << bitRes) - 1;
62         instruction |= (instNorm << bitRes);
63         for (j = 0; j < 6; j++)
64           data[i + j + bytePos] = (Byte)(instruction >> (8 * j));
65       }
66     }
67   }
68   return i;
69 }
70