Revert "Revert "add some optimization tags""

This reverts commit 980745a2223627afbd6e9d45538bed26452d57e3.
Revert "fix linaro memset 2"

This reverts commit eb4b21272afa70ca25cd610d5dbf9598ff376753.
Revert "fix linaro memset"

This reverts commit 19d26dc6af53461a4cb77f9fafe96602a2ce886c.
compile with arm-eabi- gcc 3.7
version 1.5.8