Jakub Jelinek wrote: On Thu, Sep 15, 2016 at 03:16:52PM +0100, Szabolcs Nagy wrote: > > > > from libc point of view, rawmemchr is a rarely used > > nonstandard function that should be optimized for size. > > (glibc does not do this now, but it should in my opinion.) > > rawmemchr with 0 is to strlen conceptually like stpcpy is to strcpy. > Are you arguing that glibc should implement strcpy using stpcpy, or vice > versa?
stpcpy is not conceptually the same, but for mempcpy, yes. By default it's converted into memcpy in the GLIBC headers and the generic implementation. stpcpy uses strlen and memcpy which is generally the most efficient version (it even beat several assembler implementations). > rawmemchr is certainly not rarely used, strchr (p, 0) is optimized to >__rawmemchr by the glibc header macros, so it is very frequently used. That's pretty much its only use, so not an argument for rawmemchr really but for optimizing strchr (p, 0) better. Wilco
