Linux manages to have three separate orderings of the arguments to
the clone() syscall on different architectures. In the kernel these
are selected via CONFIG_CLONE_BACKWARDS and CONFIG_CLONE_BACKWARDS2.
Clean up our implementation of this to use similar #define names
rather than a TARGET_* ifdef ladder.

This includes behaviour changes fixing bugs on cris, x86-64, m68k,
openrisc and unicore32.  cris had explicit but wrong handling; the
others were just incorrectly using QEMU's default, which happened
to be the equivalent of CONFIG_CLONE_BACKWARDS. (unicore32 appears
to be broken in the mainline kernel in that it tries to use arg3 for
both parent_tidptr and newtls simultaneously -- we don't attempt
to emulate this bug...)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

N32 is a 64-bit cpu with a 32-bit address space.  We have
existing cpp defines for this situation, but weren't using them.

This does mean that the linux-user/mipsn32 directory must be
merged with the linux-user/mips64 directory, and differences
must be resolved via ifdefs.
Signed-off-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

Copied from mips/syscall.h.
Signed-off-by: NKhansa Butt <khansa@kics.edu.pk>
Signed-off-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3396 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3284 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2908 c046a42c-6fe2-441c-8c8c-71466251a162

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1668 c046a42c-6fe2-441c-8c8c-71466251a162