Asm volatile causing performance regressions on ARM

Eric Botcazou
Fri Feb 28 08:52:00 GMT 2014

>  So, the main question is not about triggering condition, but about the
> behavior itself. Is it correct to flush and reload all constants ? They are
> constants after all, they are even not stored in .data section but inlined
> in the code, and thus cannot be modified.

I'd think that everyone more or less agrees that this behavior of RTL CSE is 
overly conservative and ought to be relaxed.  The question is whether this can 
be done in a sensible way without totally getting rid of the barrier.

Eric Botcazou

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