Denis Chertykov schrieb: > 2011/6/21 Georg-Johann Lay: >> Ok. d_register_operand or satisfies_constraint_d would do. But I >> preferred to introduce a new constraint for 4 and avoid splitting >> *extzv altogether to keep it simple. Complexity of splitting is not a >> real advantage over writing things down directly. >> >> As avr is running out of constraint letters, I started 3-letter >> constraints 'Y**' in the style of bfin. Would be nice if 'K' was not >> already occupied or could be deprecated (is'n not really useful in >> inline asm)... > > Better to choose starting letter different to pointer register names X,Y,Z. > May be better to use underscore '_' ? > > Denis.
My preference would be to change 'K' to 'K02' and thus deprecate 'K'. Other letters are 'A', 'B', 'C', D', 'R', 'S', 'T', 'U', 'W', 'Z'. I do not like '_' as constraint. 'R' might be needed in the future for more register constraints (r24, r24-r25, r22-25, ...) and 'R' is a nice prefix. 'C' looks appealing for constant. Johann
