Re: [Tinycc-devel] Relative paths of include files are not normalised, which can break #pragma once

[Steffen Nurpmeso]

Detlef Riekenberg wrote in
 <trinity-3bcb06b1-9b2f-4bf0-8310-be13f02cdb7e-1688080498166@3c-app-webde\
 -bs37>:
 ...
 |I do not think, that we really need a 64bit hash (with 64bit multiply)
 |for the complete file content.
 |
 |In addition to the filename and the filesize, i suggest to use "st_mtime":
 | much cheaper and available for free.

How is it with file time resolution over there?
In general i see nanosecond stuff flying by.
I wouldn't really mind .. but other than that i still make heavy
use of Chris Torek's hash (as used by Berkeley DB), even though
i now mix the result as shown by Bret Mulvey.

                  for(; (c = *buf++) != '\0';)\
                          xh = (xh << 5) + xh + (unsigned char)c;\

          /* Since mixing matters mostly for pow2 spaced maps, mixing the \
           * lower 32-bit seems to be sufficient (? in practice) */\
          if(xh != 0){\
                  xh += xh << 13;\
                  xh ^= xh >> 7;\
                  xh += xh << 3;\
                  xh ^= xh >> 17;\
                  xh += xh << 5;\
          }\

Anyway faster than xxhash or siphash or something.  Even CRC-32?

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)