K 10 svn:author V 3 bsd K 8 svn:date V 27 2001-07-26T02:29:10.000000Z K 7 svn:log V 326 MFC revisions 1.464 and 1.115 of machdep.c and swtch.s respectively to provide better handling of reserved debug register bits; allows debuggers to write back the unmodified value of dr7 that they received from the traced process's PCB without it failing with EINVAL, while still preserving reserved bit settings for the CPU. END