On Fri, Jun 22, 2012 at 11:57 AM, Uros Bizjak <ubiz...@gmail.com> wrote: > Please do not introduce new macro, just use #ifdef > HAVE_AS_IX86_REP_BSFBSR directly in i386.md.
Would you want the same #ifdef in two places if I extend this to handle 'rep ret' too, or would a macro then be preferable? To me, the macro is nicer because it avoids the temptation to repeat nontrivial bits on both sides of an #ifdef, as your example does. > OK for mainline SVN with this change. I'm not a GCC committer. > On a related note, gcc is also emitting "rep; ret". Do we need the > same treatment here too? I noticed that but ignored it because the variant target I'm working on avoids that case anyway (for unrelated reasons). I haven't extended the assembler to handle 'rep ret', but it would be trivial to do so and I think it would make sense to do that and then make GCC emit 'rep ret' when supported too, just on general principles. I'll see if I can make the assembler change today and follow up with a new version of this patch that handles the 'ret' case too. Thanks, Roland
