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Speed up generation of Unicode hash functions.

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Sets of Unicode keys are picky about the primes used when generating
a perfect hash function for them. Callers can spend many seconds
iterating through all the possible combinations of candidate
multipliers and seeds to find one that works.

Unicode updates typically happen only once a year, but it still makes
development and testing of Unicode scripts unnecessarily slow. To fix,
iterate over the primes in the innermost loop. This does not change
any existing functions checked into the tree.
This commit is contained in:
John Naylor 2021-08-12 09:08:56 -04:00
parent b05f7ecec4
commit ba958299ea
1 changed files with 4 additions and 4 deletions
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8
src/tools/PerfectHash.pm
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@ -87,13 +87,13 @@ sub generate_hash_function
my $hash_seed2;
my @subresult;
FIND_PARAMS:
foreach (17, 31, 127, 8191)
for ($hash_seed1 = 0; $hash_seed1 < 10; $hash_seed1++)
{
$hash_mult2 = $_; # "foreach $hash_mult2" doesn't work
for ($hash_seed1 = 0; $hash_seed1 < 10; $hash_seed1++)
for ($hash_seed2 = 0; $hash_seed2 < 10; $hash_seed2++)
{
for ($hash_seed2 = 0; $hash_seed2 < 10; $hash_seed2++)
foreach (17, 31, 127, 8191)
{
$hash_mult2 = $_; # "foreach $hash_mult2" doesn't work
@subresult = _construct_hash_table(
$keys_ref, $hash_mult1, $hash_mult2,
$hash_seed1, $hash_seed2);