On Sun, Dec 05, 2010 at 09:16:53AM -0000, pet...@apache.org wrote: > Author: peters > Date: Sun Dec 5 09:15:42 2010 > New Revision: 1042294 > > URL: http://svn.apache.org/viewvc?rev=1042294&view=rev > Log: > Optimize and simplify svn_checksum_parse_hex(). In my tests, the new > version is 20% to 30% faster. The EBCDIC port would probably need an > #ifdef here. > > Also happens to fix the case of input with uppercase A-F characters. > We neither parsed them correctly nor rejected them as invalid. > Now we accept _and_ parse them correctly. > > * subversion/libsvn_subr/checksum.c > (svn_checksum_parse_hex): Rewrite to do a single table lookup to find > the validity and value of a hex byte, rather than two lookups > (svn_ctype_isxdigit, svn_ctype_isalpha) plus some ASCII math. > Also, don't bother to qualify char as unsigned except where actually > needed, and rename is_zeros to is_nonzero to match its meaning. > > Modified: > subversion/trunk/subversion/libsvn_subr/checksum.c > - is_zeros |= (*checksum)->digest[i]; > + is_nonzero |= ((char *)(*checksum)->digest)[i] = x1 << 4 | x2;
At the very least, this needs parenthesis unless you want everyone to pull out their copy of K&R to check operator precedence rules. Can we do one assignment per line instead? Maybe that's easier to parse. Stefan
