From 812c9c9758e1503bd1725af9c6fe9ede6a467506 Mon Sep 17 00:00:00 2001 From: Pekka Paalanen Date: Tue, 8 Sep 2015 13:35:33 +0300 Subject: [PATCH] implementation: add PIXMAN_DISABLE=wholeops Add a new option to PIXMAN_DISABLE: "wholeops". This option disables all whole-operation fast paths regardless of implementation level, except the general path (general_composite_rect). The purpose is to add a debug option that allows us to test optimized iterator paths specifically. With this, it is possible to see if: - fast paths mask bugs in iterators - compare fast paths with iterator paths for performance The effect was tested on x86_64 by running: $ PIXMAN_DISABLE='' ./test/lowlevel-blt-bench over_8888_8888 $ PIXMAN_DISABLE='wholeops' ./test/lowlevel-blt-bench over_8888_8888 In the first case time is spent in sse2_composite_over_8888_8888(), and in the latter in sse2_combine_over_u(). Signed-off-by: Pekka Paalanen Reviewed-by: Oded Gabbay --- pixman/pixman-implementation.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/pixman/pixman-implementation.c b/pixman/pixman-implementation.c index 5884054..2c7de4c 100644 --- a/pixman/pixman-implementation.c +++ b/pixman/pixman-implementation.c @@ -380,6 +380,11 @@ _pixman_disabled (const char *name) return FALSE; } +static const pixman_fast_path_t empty_fast_path[] = +{ + { PIXMAN_OP_NONE } +}; + pixman_implementation_t * _pixman_choose_implementation (void) { @@ -397,5 +402,16 @@ _pixman_choose_implementation (void) imp = _pixman_implementation_create_noop (imp); + if (_pixman_disabled ("wholeops")) + { + pixman_implementation_t *cur; + + /* Disable all whole-operation paths except the general one, + * so that optimized iterators are used as much as possible. + */ + for (cur = imp; cur->fallback; cur = cur->fallback) + cur->fast_paths = empty_fast_path; + } + return imp; } -- 2.34.1