On Thu, Jun 08, 2006 at 08:50:13AM -0700, Andrew Pinski wrote: > > On Jun 7, 2006, at 11:13 PM, Uros Bizjak wrote: > > >Hello! > > > >Current mainline gcc can efficiently disable x87 instruction when > >-mno-80387 switch is used. In this case, MMX registers can be used for > >the autovectorisation even without emms or femms instructions to > >switch back to x87 mode. > > I don't think so, because another function could use x87 instructions > even without you knowing it.
But it would not be difficult to check regs_ever_live[] and emit the (f)emms instruction in the epilogue if an MMX register was ever used. -- Rask Ingemann Lambertsen