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

*** 15,25 ****
  # Copyright 2021 Tintri by DDN, Inc. All rights reserved.
  # Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
  # Copyright 2023 Oxide Computer Company
  #
  
! SUBDIRS_i386 = i386 imc zen_umc
  
  SUBDIRS =       \
                  cores \
                  ddi_ufm \
                  definit \
--- 15,25 ----
  # Copyright 2021 Tintri by DDN, Inc. All rights reserved.
  # Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
  # Copyright 2023 Oxide Computer Company
  #
  
! SUBDIRS_i386 = i386 imc zen_umc xsave
  
  SUBDIRS =       \
                  cores \
                  ddi_ufm \
                  definit \
*** 48,57 ****
--- 48,58 ----
          clock_gettime \
          eventfd \
          odirectory \
          OS-6097 \
          ucontext \
+         getcontext_extd \
          writev
  
  CPPFLAGS += -D_REENTRANT
  PROGS32 = $(PROGS:%=%.32)
  PROGS64 = $(PROGS:%=%.64)