performance: Cache CLI2::canonicalize lookups

Canonicalization of attributes or attribute prefixes happens once per
every single task considered in the filtering process. It maps short,
prefixed names to their full-length versions, for example:

"pro" -> "project" in the expression "project:Home"

It follows that such process is not task-dependant and as such the
lookups can be cached.
This commit is contained in:
Tomas Babej 2021-04-23 22:35:04 -04:00
parent ab7f5b0b51
commit a19773873a
2 changed files with 17 additions and 2 deletions

View file

@ -699,8 +699,19 @@ const std::vector <std::string> CLI2::getWords ()
bool CLI2::canonicalize (
std::string& canonicalized,
const std::string& category,
const std::string& value) const
const std::string& value)
{
// Utilize a cache mapping of (category, value) -> canonicalized value.
// This cache does not need to be invalidated, because entities are defined
// only once per initialization of the Context object.
int cache_key = 31 * std::hash<std::string>{} (category) + std::hash<std::string>{} (value);
auto cache_result = _canonical_cache.find (cache_key);
if (cache_result != _canonical_cache.end())
{
canonicalized = cache_result->second;
return true;
}
// Extract a list of entities for category.
std::vector <std::string> options;
auto c = _entities.equal_range (category);
@ -710,6 +721,7 @@ bool CLI2::canonicalize (
if (value == e->second)
{
canonicalized = value;
_canonical_cache[cache_key] = value;
return true;
}
@ -721,6 +733,7 @@ bool CLI2::canonicalize (
if (autoComplete (value, options, matches, minimumMatchLength) == 1)
{
canonicalized = matches[0];
_canonical_cache[cache_key] = matches[0];
return true;
}