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Re: [PATCH] Introduce abi_word_mode
> You're trying to argue we should fix the feature, but I don't think
> there's anything to salvage. You've also pointed out that the most
> obvious uses of this (mis)feature are in GCC itself -- and those we can
> fix, in a way that will help you achieve your goal of mixed
> 32-bit/64-bit code.
I think one of the reasons for the abi_word_mode idea was that we never
considered it feasible to get rid of attribute(mode(word)) completely and
without a longer deprecation phase. But if the middle-end maintainers agree
to remove it immediately abi_word_mode would be obsolete. In that case we
could go on trying to fix the other middle-end abuses of word_mode which stand
in the way and post the patches to introduce the 64bit optimizations for
I would like to work on a patch removing attribute(mode(word)) but currently
I don't see how the use of the attribute to define Unwind_Word can be replaced without
introducing another strange mechanism to statisfy all architectures. If we would
try to replace it with mode(SI) or mode(DI) I think we would have to add tons of
target macro checks to unwind.h to do the right thing for every back-end
configuration. Basically we would have to mimic the logic used in each backend
to define UNITS_PER_WORD (except for rs6000 and the modified S/390 back-end of
course where we would do what abi_word_mode would do).