From 6d6fce257cf666113e982c0887121739dff5bf1d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Sun, 1 Apr 2012 09:28:34 +0200 Subject: Eliminate prefetch for conditional instructions Not pre-fetching in conditional instructions (instructions that use -fail_action) seems to improve performance slightly. The reason for that is that conditional instructions may jump to the failure label, wasting the pre-fetched instruction. Another reason is that that many conditional instructions do a function call, and the register pressure is therefore high. Avoiding the pre-fetch may reduce the register pressure and pontentially result in more efficient code. --- erts/emulator/beam/ops.tab | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'erts/emulator/beam') diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab index bce6bacd5c..3d52da77d3 100644 --- a/erts/emulator/beam/ops.tab +++ b/erts/emulator/beam/ops.tab @@ -477,7 +477,7 @@ i_is_ne_exact_literal f x c i_is_ne_exact_literal f y c is_eq_exact Lbl Y=y X=x => is_eq_exact Lbl X Y -%macro: is_eq_exact EqualExact -fail_action +%macro: is_eq_exact EqualExact -fail_action -pack is_eq_exact f x x is_eq_exact f x y is_eq_exact f s s -- cgit v1.2.3