On 05/18/2011 11:55 AM, Andrew Stubbs wrote: > > case SIGN_EXTEND: > + op = make_compound_operation (op, SET); > +
I would have expected that bit to go into the MULT case (doing it for both operands), so that the effect is limited to just making widening multiplies more obvious. Also, using make_compound_operation unchanged is probably not safe - it calls SUBST which I think is only valid during combine. I think you may have to break out the non-recursive part into a make_compound_operation_1 (probably to be placed into simplify-rtx.c). Bernd