15254 %ymm registers not restored after signal handler
15367 x86 getfpregs() summons corrupting %xmm ghosts
15333 want x86 /proc xregs support (libc_db, libproc, mdb, etc.)
15336 want libc functions for extended ucontext_t
15334 want ps_lwphandle-specific reg routines
15328 FPU_CW_INIT mistreats reserved bit
15335 i86pc fpu_subr.c isn't really platform-specific
15332 setcontext(2) isn't actually noreturn
15331 need <sys/stdalign.h>
Change-Id: I7060aa86042dfb989f77fc3323c065ea2eafa9ad
Conflicts:
    usr/src/uts/common/fs/proc/prcontrol.c
    usr/src/uts/intel/os/archdep.c
    usr/src/uts/intel/sys/ucontext.h
    usr/src/uts/intel/syscall/getcontext.c

*** 200,209 ****
--- 200,210 ----
                  fstatvfs.2                      \
                  futimes.2                       \
                  futimesat.2                     \
                  futimens.2                      \
                  getaudit_addr.2                 \
+                 getcontext_extd.2               \
                  getegid.2                       \
                  geteuid.2                       \
                  getgid.2                        \
                  getpgid.2                       \
                  getpgrp.2                       \
*** 318,327 ****
--- 319,329 ----
  setaudit.2                      := LINKSRC = getaudit.2
  setaudit_addr.2                 := LINKSRC = getaudit.2
  
  setauid.2                       := LINKSRC = getauid.2
  
+ getcontext_extd.2               := LINKSRC = getcontext.2
  setcontext.2                    := LINKSRC = getcontext.2
  
  setgroups.2                     := LINKSRC = getgroups.2
  
  setitimer.2                     := LINKSRC = getitimer.2