From 5b70e7e2df94410e7e3ceeb6e54f4ebe72b87b7d Mon Sep 17 00:00:00 2001 From: "commit-bot@chromium.org" Date: Thu, 6 Mar 2014 14:57:46 +0000 Subject: [PATCH] Manually set fFilterValues in SkConvolutionFilter1D. Using fFilterValues.reset() or a loop of fFilterValues.push_back() is about 5x slower than calling fFilterValues.resize_back() and then looping using primitive [] and =. This is only going to show up if you apply https://codereview.chromium.org/183763047/, where it yields about 2.5% speedup in the bitmap resize microbenchmarks on a Linux desktop. Ceteris paribus, it should actually improve rasterization time of drawBitmapRectToRect() with a resize by about 5% in Chromium. BUG=skia:2258 R=humper@google.com, tomhudson@google.com Author: tomhudson@chromium.org Review URL: https://codereview.chromium.org/184323003 git-svn-id: http://skia.googlecode.com/svn/trunk@13681 2bbb7eff-a529-9590-31e7-b0007b416f81 --- src/core/SkConvolver.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/core/SkConvolver.cpp b/src/core/SkConvolver.cpp index 7666e6fadc..e26c8e79e6 100644 --- a/src/core/SkConvolver.cpp +++ b/src/core/SkConvolver.cpp @@ -294,8 +294,10 @@ void SkConvolutionFilter1D::AddFilter(int filterOffset, filterLength = lastNonZero + 1 - firstNonZero; SkASSERT(filterLength > 0); + // Calling fFilterValues.reset(), or push_back() in a loop, are expensive. + fFilterValues.resize_back(filterLength); for (int i = firstNonZero; i <= lastNonZero; i++) { - fFilterValues.push_back(filterValues[i]); + fFilterValues[i - firstNonZero] = filterValues[i]; } } else { // Here all the factors were zeroes.