From d33bf3d6649ce049a12fcf7d629e551066f41c47 Mon Sep 17 00:00:00 2001 From: Yunqing Wang Date: Fri, 28 May 2010 14:34:39 -0400 Subject: [PATCH] Remove costly memory reads/writes in vp8_reset_mb_tokens_context() Tests on x86 showed this function costed 2.7% of total decoding time because of all the memory reads/writes. After modification, it only costs about 0.7% of decoding time, which gives a 2% gain. Change-Id: I5003ee30b6dc6dea0bfa42a6ad7e7c22fcc7b215 --- vp8/decoder/detokenize.c | 47 ++++++++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 14 deletions(-) diff --git a/vp8/decoder/detokenize.c b/vp8/decoder/detokenize.c index a42f18dd7..c081518fb 100644 --- a/vp8/decoder/detokenize.c +++ b/vp8/decoder/detokenize.c @@ -67,23 +67,42 @@ void vp8_reset_mb_tokens_context(MACROBLOCKD *x) ENTROPY_CONTEXT *l; int i; - for (i = 0; i < 24; i++) - { - - a = A[ vp8_block2context[i] ] + vp8_block2above[i]; - l = L[ vp8_block2context[i] ] + vp8_block2left[i]; - - *a = *l = 0; - } - + /* Clear entropy contexts for Y blocks */ + a = A[Y1CONTEXT]; + l = L[Y1CONTEXT]; + *a = 0; + *(a+1) = 0; + *(a+2) = 0; + *(a+3) = 0; + *l = 0; + *(l+1) = 0; + *(l+2) = 0; + *(l+3) = 0; + + /* Clear entropy contexts for U blocks */ + a = A[UCONTEXT]; + l = L[UCONTEXT]; + *a = 0; + *(a+1) = 0; + *l = 0; + *(l+1) = 0; + + /* Clear entropy contexts for V blocks */ + a = A[VCONTEXT]; + l = L[VCONTEXT]; + *a = 0; + *(a+1) = 0; + *l = 0; + *(l+1) = 0; + + /* Clear entropy contexts for Y2 blocks */ if (x->mbmi.mode != B_PRED && x->mbmi.mode != SPLITMV) { - a = A[Y2CONTEXT] + vp8_block2above[24]; - l = L[Y2CONTEXT] + vp8_block2left[24]; - *a = *l = 0; + a = A[Y2CONTEXT]; + l = L[Y2CONTEXT]; + *a = 0; + *l = 0; } - - } DECLARE_ALIGNED(16, extern const unsigned int, vp8dx_bitreader_norm[256]); #define NORMALIZE \ -- 2.40.0