diff options
Diffstat (limited to 'build2/variable.txx')
-rw-r--r-- | build2/variable.txx | 58 |
1 files changed, 34 insertions, 24 deletions
diff --git a/build2/variable.txx b/build2/variable.txx index 5b212f0..5a1b79c 100644 --- a/build2/variable.txx +++ b/build2/variable.txx @@ -557,13 +557,14 @@ namespace build2 // template <typename K> pair<value&, ulock> variable_cache<K>:: - insert (K k, const lookup& stem) + insert (K k, const lookup& stem, size_t ver) { - const variable_map* vars (stem.vars); // NULL if undefined. - size_t ver ( - stem.defined () - ? static_cast<const variable_map::value_data*> (stem.value)->version - : 0); + using value_data = variable_map::value_data; + + const variable_map* svars (stem.vars); // NULL if undefined. + size_t sver (stem.defined () + ? static_cast<const value_data*> (stem.value)->version + : 0); shared_mutex& m ( variable_cache_mutex_shard[ @@ -576,9 +577,10 @@ namespace build2 // Cache hit. // - if (i != m_.end () && - i->second.stem_vars == vars && - i->second.stem_version == ver) + if (i != m_.end () && + i->second.version == ver && + i->second.stem_vars == svars && + i->second.stem_version == sver) return pair<value&, ulock> (i->second.value, move (ul)); // Relock for exclusive access. Note that it is entirely possible @@ -593,30 +595,38 @@ namespace build2 pair<typename map_type::iterator, bool> p (i, i == m_.end ()); if (p.second) - p = m_.emplace (move (k), entry_type {value (nullptr), vars, ver}); + p = m_.emplace (move (k), + entry_type {value_data (nullptr), ver, svars, sver}); entry_type& e (p.first->second); - // Cache miss. - // if (p.second) - ; - // - // Cache invalidation. - // - else if (e.stem_vars != vars || e.stem_version != ver) { - if (e.stem_vars != vars) - e.stem_vars = vars; + // Cache miss. + // + e.value.version++; // New value. + } + else if (e.version != ver || + e.stem_vars != svars || + e.stem_version != sver) + { + // Cache invalidation. + // + assert (e.version <= ver); + e.version = ver; + + if (e.stem_vars != svars) + e.stem_vars = svars; else - assert (e.stem_version <= ver); + assert (e.stem_version <= sver); + + e.stem_version = sver; - e.stem_version = ver; + e.value.version++; // Value changed. } - // - // Cache hit. - // else + // Cache hit. + // ul.unlock (); return pair<value&, ulock> (e.value, move (ul)); |