arithmetic standard pattern using only memory_operand

[BELBACHIR Selim]

Hi,

My target has arithmetic instruction whose operands can ONLY be memory (offseted, post/pre inc, ...).

For example 'add' can only have a memory operand as its first operand :

add mem($C1), $C2, $C3



I tried to simply write the addsi3 pattern with using memory_operand as predicate for operand 2 but gcc often (always?) tries to use a register instead of memory and finally send the error message : 

unrecognizable insn :
set (reg:SI 0) (plus:SI (reg SI 1) (reg SI 2))


Is it possible to define arithmetic standard parttern with operands matched by memory_operand only ? How ?
Maybe I forgot a important MACRO in may <target>.h ?


	Regards,

		Selim