On Mon, Feb 12, 2018 at 11:23:05AM +0000, Andrew Cooper wrote: > .macro ALTERNATIVE oldinstr, newinstr, feature > .L\@_orig_s: > \oldinstr > .L\@_orig_e: > + .skip (-((repl_len(1) - orig_len) > 0) * (repl_len(1) - orig_len)), 0x90
clang chokes on this expression, because of the negation at the beginning and I'm also failing to see why are you adding such negation. AFAICT using: .skip (((repl_len(1) - orig_len) > 0) * (repl_len(1) - orig_len)), 0x90 Is correct: it adds the right padding if the alternative code is bigger than the original one, while not adding anything is the original code is greater than the alternative one. The negation just turns the 1 to -1, thus converting the result of the whole expression into a negative value. Roger. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
