h/fish-shell
1
Fork 0
mirror of https://github.com/fish-shell/fish-shell.git synced 2026-06-18 03:41:16 -03:00
Code Issues Packages Projects Releases Wiki Activity

Optimize function calls by reducing inherit vars heap allocations and copies

Browse Source 
* Convert `function_get_inherit_vars()` to return a reference to the
  (possibly) existing map, rather than a copy;
* Preallocate and reuse a static (read-only) map for the (very) common
  case of no inherited vars;
* Pass references to the inherit vars map around thereafter, never
  triggering the map copy (or even move) constructor.

NB: If it turns out the reference is unsafe, we can switch the inherit vars
to be a shared_ptr and return that instead.
This commit is contained in:
Mahmoud Al-Qudsi
2019-04-13 11:26:10 -05:00
parent 56125f73e4
commit cdce8511a1
4 changed files with 7 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/function.h
View File

@@ -102,7 +102,7 @@ int function_get_definition_lineno(const wcstring &name);
/// Returns a mapping of all variables of the specified function that were inherited from the scope
/// of the function definition to their values.
std::map<wcstring, env_var_t> function_get_inherit_vars(const wcstring &name);
const std::map<wcstring, env_var_t> &function_get_inherit_vars(const wcstring &name);
/// Creates a new function using the same definition as the specified function. Returns true if copy
/// is successful.