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Re: loop hoisting fails
On 10/02/11 17:59, Richard Henderson wrote:
If constants are never valid as the source of a store,
They are but it really depends to which registers they are going to. If
the destination belongs to a certain class it is ok, for all the others
it is not. It is tricky even to define costs when you are given:
rtx_costs of (const_int 0), outer_code SET.
This might be very, very cheap or very, very expensive for certain
classes of registers.