This is the mail archive of the libc-hacker@sources.redhat.com mailing list for the glibc project.
Note that libc-hacker is a closed list. You may look at the archives of this list, but subscription and posting are not open.
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |
On Tue, Aug 21, 2001 at 10:46:30PM +0200, Jakub Jelinek wrote: > The attached strncpy.S beats them all for small strings (or sizes) or for > aligned strings, unfortunately for some strange reason strnlen+memcpy+memset > is faster for long unaligned strings (unaligned is ((dst^src) & 0x7) != 0). > Can any IA-64 assembly hacker look into it? (p5) ld1 c = [src], 1 // c = *src++ ;; st1 [dest] = c, 1 // *dest++ = c IA-64 won't write-combine smaller than 8 (or 4) bytes. You'll get something like a 6 cycle stall writing to sequential bytes like this. If you want to quickly copy unaligned data, you have to play word shifting games. r~
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |