------- Comment #7 from vmakarov at redhat dot com 2009-06-29 19:44 ------- Paolo, Steven, thanks for looking into this problem. Using the mips approach is a good idea. Although the costs of FLOAT_REGS and SSE_REGS are the same in ira-costs.c, IRA should prefer SSE_REGS or FLOAT_REGS depending on -fpmath= option.
The implementation will take some time because choosing a cover class depends not only on order of them in IRA_COVER_CLASSES macro but also on order of them in enum reg_class. I hope I'll have a patch on this week. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37488
