On 10/10/13 03:25, Zhenqiang Chen wrote:
It comes from Coremark. The code is:
if (NEXT_SYMBOL == '+' || NEXT_SYMBOL == '-')
I should have guessed ;-)
For ARM, there are three instructions rather than 4 (in thumb state).
For some older gcc, I got performance improvement on ARM chromebook. But I
can not reproduce the performance gain now.
I will collect logs during GCC bootstrap.
Thanks. It doesn't have to be anything particularly complex. When I'm
looking at a transformation I usually just put a printf when it triggers
and grep for the string in a make log.
Depending on what I'm doing, I may dig more deeply into the situations
where its triggering to make sure I fully understand the primary and
secondary effects of a transformation which often leads to tweaking the
implementation. I don't think that level of rigor is needed here.
Jeff