------- Comment #15 from thutt at vmware dot com 2009-02-10 15:35 ------- (In reply to comment #14) > > > OTOH, constraints should be used to support correct register > > > allocation for machine instructions, not to emulate ABI in order to > > > support calls from inside asm statements. > > > > Please indulge me for a moment. > > > > What exactly is a call? > > > > Are you considering the only method of transferring control to be the > > standard 'near call' & 'near ret' instructions on the x86? > > I was referring at the procedure call, where you need to setup outgoing > arguments on the calling point and setup incoming arguments on caller point. > gcc will magically match these two no matter what ABI-changing compile flag > (i.e. -mregparm) you use. When you call procedure from inside asm, gcc does > not > know about that, and there is no way that gcc will know where arguments are to > be found.
I understand. I'm not expecting gcc to handle those aspects of the inline assembly. My request is just to be able to specify any GP hardware register in a constraint. Both input & output. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16331
