HI Bero,
What I did was changing both Os and O2 to O3 in TARGET_linux-arm.mk. I did not change those O2/Os specified in each module internally. As there may be a reason for the module itself to specify the optimisation level. I think it is risky to change those. But I don't think it should be a big problem.
Thanks and regards Chao
On 19 August 2011 15:38, Bernhard Rosenkranzer < bernhard.rosenkranzer@linaro.org> wrote:
Hi,
On 18 August 2011 19:40, Chao Yang chao.yang@linaro.org wrote:
The results can be found at https://wiki.linaro.org/ChaoYang/Sandbox/gccoptimization.
Interesting... I'd have expected getting rid of -fno-strict-aliasing gives the biggest performance boost, but I'd have expected O3 to be a bit more effective than it is... Are you sure the relevant parts actually use O3 (keep in mind that e.g. -O3 + -Os = -Os -- whatever is specified later (LOCAL_CFLAGS, ...) is effective)?
Could you add another combination to the benchmark? I'm curious about -O3 -fno-inline-functions (function inlining is always a bit of a 2-edged sword because of the code size increases...)
ttyl bero