mirror of
https://github.com/Ryujinx/Ryujinx.git
synced 2024-12-05 04:02:00 +00:00
8c85bdf2ed
* cpu-misc_opt * B = ~b * ;
111 lines
2.6 KiB
C#
111 lines
2.6 KiB
C#
namespace ARMeilleure.Common
|
|
{
|
|
static class BitUtils
|
|
{
|
|
private const int DeBrujinSequence = 0x77cb531;
|
|
|
|
private static readonly int[] DeBrujinLbsLut;
|
|
|
|
private static readonly sbyte[] HbsNibbleLut;
|
|
|
|
static BitUtils()
|
|
{
|
|
DeBrujinLbsLut = new int[32];
|
|
|
|
for (int index = 0; index < DeBrujinLbsLut.Length; index++)
|
|
{
|
|
uint lutIndex = (uint)(DeBrujinSequence * (1 << index)) >> 27;
|
|
|
|
DeBrujinLbsLut[lutIndex] = index;
|
|
}
|
|
|
|
HbsNibbleLut = new sbyte[] { -1, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3 };
|
|
}
|
|
|
|
public static int CountBits(int value)
|
|
{
|
|
int count = 0;
|
|
|
|
while (value != 0)
|
|
{
|
|
value &= ~(value & -value);
|
|
|
|
count++;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
public static long FillWithOnes(int bits)
|
|
{
|
|
return bits == 64 ? -1L : (1L << bits) - 1;
|
|
}
|
|
|
|
public static int HighestBitSet(int value)
|
|
{
|
|
if (value == 0)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
for (int bit = 31; bit >= 0; bit--)
|
|
{
|
|
if (((value >> bit) & 1) != 0)
|
|
{
|
|
return bit;
|
|
}
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
public static int HighestBitSetNibble(int value)
|
|
{
|
|
return HbsNibbleLut[value];
|
|
}
|
|
|
|
public static int LowestBitSet(int value)
|
|
{
|
|
if (value == 0)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
int lsb = value & -value;
|
|
|
|
return DeBrujinLbsLut[(uint)(DeBrujinSequence * lsb) >> 27];
|
|
}
|
|
|
|
public static long Replicate(long bits, int size)
|
|
{
|
|
long output = 0;
|
|
|
|
for (int bit = 0; bit < 64; bit += size)
|
|
{
|
|
output |= bits << bit;
|
|
}
|
|
|
|
return output;
|
|
}
|
|
|
|
public static int RotateRight(int bits, int shift, int size)
|
|
{
|
|
return (int)RotateRight((uint)bits, shift, size);
|
|
}
|
|
|
|
public static uint RotateRight(uint bits, int shift, int size)
|
|
{
|
|
return (bits >> shift) | (bits << (size - shift));
|
|
}
|
|
|
|
public static long RotateRight(long bits, int shift, int size)
|
|
{
|
|
return (long)RotateRight((ulong)bits, shift, size);
|
|
}
|
|
|
|
public static ulong RotateRight(ulong bits, int shift, int size)
|
|
{
|
|
return (bits >> shift) | (bits << (size - shift));
|
|
}
|
|
}
|
|
}
|