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Re: [PATCH] Fix PR middle-end/28690, indexed load/store performance + reload bug


>>>>> Michael Matz writes:

Michael> Yes, but in this case you _forbid_ some operands (namely some specific 
Michael> hardware registers), the opposite of what's allowed by the above docu.

Michael> The above docu refers to cases like allowing all constants and registers 
Michael> in the predicate, where the constraint then only allows restricted 
Michael> constants (and at least one register to make necessary reloads).

	The hardware does not allow some special registers.  The
constraints correctly restrict the operands.  The predicate tries to match
the constraints more closely than allowing all registers.  I do not see
how this contradicts the documentation.

David



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