bwtIntrosortFrom

private fn

void bwtIntrosortFrom(uint[]  indices,  const(ubyte)[]  block,
       size_t lo,  size_t hi,  size_t depthLimit,  size_t compareOffset)

pure nothrow

Introsort implementation that skips already-compared prefix bytes.

When called from radix sort, we know the first compareOffset bytes are already equal, so we can skip comparing them.

`indices`	Array of indices to sort.
`block`	The data block.
`lo`	Start of range (inclusive).
`hi`	End of range (exclusive).
`depthLimit`	Recursion depth limit before switching to heapsort.
`compareOffset`	Number of prefix bytes to skip in comparisons.