Mercurial > hg > index.cgi
diff lwlib/lw_expr.h @ 337:3b5a45c6ab92
Speed improvement to lw_expr
Instead of using a singly linked list and doing the slow append algorithm
when adding an operand to an expression (scan from the start to find the
end), now maintain a tail pointer. Also maintain a previous pointer in each
entry. Benchmarking suggests this yields a rougly 30% improvement in
runtime.
Also refactor some of the code in lw_expr.c to make it somewhat clearer to
understand. For some values of clearer and understand.
| author | William Astle <lost@l-w.ca> |
|---|---|
| date | Sat, 02 Aug 2014 10:08:01 -0600 |
| parents | 1f1a28b797e1 |
| children | 6138e304ab9a |
line wrap: on
line diff
--- a/lwlib/lw_expr.h Thu Jul 31 17:20:11 2014 -0600 +++ b/lwlib/lw_expr.h Sat Aug 02 10:08:01 2014 -0600 @@ -58,6 +58,7 @@ { lw_expr_t p; struct lw_expr_opers *next; + struct lw_expr_opers *prev; }; struct lw_expr_priv @@ -66,6 +67,7 @@ int value; // integer value void *value2; // misc pointer value struct lw_expr_opers *operands; // ptr to list of operands (for operators) + struct lw_expr_opers *operand_tail; // ptr to last operand }; typedef lw_expr_t lw_expr_fn_t(int t, void *ptr, void *priv);