passes/pmgen/ice40_wrapcarry.pmg - third_party/yosys - Git at Google

 pattern ice40_wrapcarry

 match carry
 	select carry->type.in(\SB_CARRY)
 endmatch

 match lut
 	select lut->type.in(\SB_LUT4)
 	index <SigSpec> port(lut, \I1) === port(carry, \I0)
 	index <SigSpec> port(lut, \I2) === port(carry, \I1)
 endmatch
	pattern ice40_wrapcarry

	match carry
	select carry->type.in(\SB_CARRY)
	endmatch

	match lut
	select lut->type.in(\SB_LUT4)
	index <SigSpec> port(lut, \I1) === port(carry, \I0)
	index <SigSpec> port(lut, \I2) === port(carry, \I1)
	endmatch