>> > http://gcc.gnu.org/ml/gcc-patches/2013-09/msg00884.html > > This patch seems resonable. (in fact I have pretty much same in my tree) > use_vector_fp_converts is actually trying to solve the same problem in AMD > hardware - you need to type the whole register when converting. > So it may work well for AMD chips too or may be the difference is that > Intel chips somehow handle "cvtpd2ps %xmm0, %xmm0" well even though > the upper half of xmm0 is ill defined, while AMD chips doesn't. > > The patch seems OK. I do not see rason for > && peep2_reg_dead_p (0, operands[0]) > test. Reg has to be dead since it is full destination of the operation.
Ok, I see. I will delete it. > > Lets wait few days before commit so we know effect of > individual changes. I will test it on AMD hardware and we can decide on > generic tuning then. > > Honza Ok, thanks. Wei Mi.