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Re: Add znver2 scheduler model
> this patch adds znver2 scheduler model. Znver2 is close enough to znver1
> that I have decided to implement it in one automaton. The main
> difference is extra AGU unit that seems to be used for store only
> (according to CPU diagram), the fact that 256bit vector operations are
> no longer split (and thus they behave like 128bit) and reduced latency
> of fp multiply and conversion operations.
> The patch seems to have very little effect on overall performance but
> since we do not model the out of order core and thus we think that the
> CPU is mostly starved by not having enough parallelism to exectue.
> Still it is better to be precise.
> Bootstrapped/regtested x86_64-linux, commited.
> * common/config/i386/i386-common.c: Use PROCESSOR_ZNVER2 scheduler for
> * config/i386/znver1.md: Enable patterns for znver2 and add store
> variants which use extra AGU unit.
I have backported this patch to gcc 9 branch now too.