On Sunday, 23 June 2013 at 21:22:40 UTC, Walter Bright wrote:
https://github.com/D-Programming-Language/dmd/blob/master/src/root/stringtable.c#L21
Profiling shows the calcHash function is a significant
contributor to compilation time (3.25% of total time). So
making it faster is a win. Even making dmd 1% faster would be a
nice win - all those little drops add up.
There are many, many string hash functions findable through
google. Anyone want to spend the effort to make a faster one?
Remember, ya gotta prove it's faster!
A nice timing test would be the time expending compiling
Phobos. I would suggest that the 64 bit build of dmd be used
for timing tests.
Also, be careful, many of those hash functions on the intarnets
have a license that makes it unusable for dmd.
My first idea was to look at Python, since it requires a lot of
hash calculation dynamically and probably is one of the most
tuned implementations. Interesting how naive it is:
http://hg.python.org/cpython/file/7aab60b70f90/Objects/object.c#l759
Just a simple for loop over chars. No switch.
Wikipedia: "Python Software Foundation License (PSFL) is a
BSD-style permissive free software license"
