On 02/13/2013 05:31 PM, Linus Torvalds wrote: > On Wed, Feb 13, 2013 at 4:54 PM, H. Peter Anvin <hpa@xxxxxxxxx> wrote: >> >> It does for the callee, but only on a whole-file basis. It would be a >> lot nicer if we could do it with function attributes. > > A way to just set the callee-clobbered list on a per-function basis > would be lovely. Gcc has limited support for this on some > architectures, where you can specify "save every register for this > function" in order to do things like interrupt handlers etc without > even resorting to asm. But there is no generic (or even just x86) > support for anything like it :-( > > There are other calling-convention attributes that make me suspect gcc > could easily do this (it already supports per-function ABI > specification, so presumably it already has some concept of > callee-saved registers being different for different attributes), but > from my reading you currently have to generate asm wrappers by hand > (and call them by hand with inline asm) if you want to do something > like this. > I just filed a gcc bugzilla on this: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56314 -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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