private static int[] FindCandidate(byte[] input, int inputIndex, int inputLimit, int inputOffset, int shift, short[] table, int skip)
{
int candidateIndex = 0;
for (inputIndex += 1; inputIndex + BytesBetweenHashLookups(skip) <= inputLimit; inputIndex += BytesBetweenHashLookups(skip++))
{
int currentInt = DataHelper.LoadInt(input, inputIndex);
int hash = HashBytes(currentInt, shift);
candidateIndex = inputOffset + table[hash];
Debug.Assert(candidateIndex >= 0);
Debug.Assert(candidateIndex < inputIndex);
table[hash] = (short)(inputIndex - inputOffset);
if (currentInt == DataHelper.LoadInt(input, candidateIndex))
{
break;
}
}
return(new int[] { inputIndex, candidateIndex, skip });
}
private static int[] EmitCopies(
byte[] input,
int inputOffset,
int inputSize,
int inputIndex,
byte[] output,
int outputIndex,
short[] table,
int shift,
int candidateIndex)
{
int inputBytes;
do
{
int matched = 4 + FindMatchLength(input, candidateIndex + 4, input, inputIndex + 4, inputOffset + inputSize);
int offset = inputIndex - candidateIndex;
inputIndex += matched;
outputIndex = EmitCopy(output, outputIndex, offset, matched);
if (inputIndex >= inputOffset + inputSize - INPUT_MARGIN_BYTES)
{
return(new int[] { inputIndex, outputIndex });
}
int previous = DataHelper.LoadInt(input, inputIndex - 1);
inputBytes = DataHelper.LoadInt(input, inputIndex);
int previousHash = HashBytes(previous, shift);
table[previousHash] = (short)(inputIndex - inputOffset - 1);
int currentHash = HashBytes(inputBytes, shift);
candidateIndex = inputOffset + table[currentHash];
table[currentHash] = (short)(inputIndex - inputOffset);
} while (inputBytes == DataHelper.LoadInt(input, candidateIndex));
return(new int[] { inputIndex, outputIndex });
}
private static int ReadTrailer(byte[] data, int index, int bytes)
{
return(DataHelper.LoadInt(data, index) & _wordmask[bytes]);
}
