🚀 go-pugleaf

A hand-transcription error butchered a line in the code previously posted.
Here is the full, unmolested test version used to derive the previous posting.
Many thanks to Dave Hudson (tdh@ksr.com) for bringing this to light.

   /Alan Paeth

----
int sparsebit(i)
    long i;
    {
    int p;
    p = 0;
/* return position 'p' on range [0..31] of a "lone bit" integer (value 2^p) */
/* otherwise, return -1. This is "little-Endian form" as the lsb is at p=0. */
    if (i == 0) return(-1);		/* no bits set */
    if ((i & (-i)) != i) return(-1);	/* two or more bits set */
    if (i & 0xAAAAAAAA) p++;
    if (i & 0xCCCCCCCC) p += 2;
    if (i & 0xF0F0F0F0) p += 4;
    if (i & 0xFF00FF00) p += 8;
    if (i & 0xFFFF0000) p += 16;
    return(p);
    }

int msbbit(i)
    long i;
    {
    long i2;
/* return the bit position of the msb as [0..31]; return -1 on arg of zero */
/*  if (i<0) return(31); */ /* speed-up assumes a 'long's msb is at pos 31 */
    while (i2 = (i & (i-1))) i = i2;
    return(sparsebit(i));
    }

main(argc, argv)
    char *argv[];
    {
    printf("%d\n", msbbit(atoi(argv[1])));
    }