Summary: * Investigate automotive benchmark. * Linaro gcc 4.6 release
Details: 1. Automotive benchmark performance analysis for different branch cost for Cortex-A9. * Debug function WriteOut, which is called 12 times on average, leads common performance issue since the IF-THEN in the function is converted to IT block, which TRUE probability is less than 4%. * Identify the root cause of performance regression with IT block for bitmnp01, rspeed01, pntrch01 and ttsprk01. Overall, - The performance of a taken bpl is better than an ITTT. If this is a common sense, for IF-THEN, we'd set branch-cost to 1. - For IF-THEN-ELSE, we'd take branch probability into account when converting it to IT block. - ifcvt might generate useless IT block. 2. Try to do Linaro GCC release. But meet several issues: * Can not branch a clean lp:gcc-linaro/4.7. As a workaround, I had downloaded a clean bzr tree from other site. For next release, I can use the local tree to create the release tarball. * All a9hf-builder ubutests fail due to test environment issue.
Plan: * Investigate more benchmarks for different branch costs.
Planed leaves: * Feb. 9 - 15: Chinese Spring Festival.
Best Regards! -Zhenqiang