Jim, After further reading, the Internals document answered my question. I realized that CONST_OK_FOR_LETTER_P is under the "Obsolete Macros for Defining Constraints" section, which states: "Machine-specific constraints can be defined with these macros instead of the machine description constructs described in Section 14.8.6 [Define Constraints], page 274. This mechanism is obsolete. New ports should not use it..." So, to answer myself: Yes, define_constraint definitions are used instead of the CONST_OK_FOR_LETTER_P macro. Thanks for your patience! -Omar On Tue, Apr 8, 2008 at 1:33 PM, Omar <gcc.omar@xxxxxxxxx> wrote: > > Jim, > First, thanks a lot for your comments. > > > It current sources, you want to define a > > $target/constraints.md file that has a (define_contraint "I" ...) pattern. > I have been looking at other targets, and they seem to use the > CONST_OK_FOR_LETTER_P macro for this purpose. > Is the define_constraint equivalent to what the macro CONST_OK_FOR > _LETTER_P used to stand for? > I am trying to understand is define_constraint replaces this macro's > functionality. > > Your comment confirms my suspicion: > > Most gcc internals stuff like this is not well documented. > > You just try it, and if it works fine, if > > it doesn't, then change it. > > -Omar >
