tcg: Optionally sign-extend 32-bit arguments for 64-bit hosts.

tcg: Optionally sign-extend 32-bit arguments for 64-bit hosts.

Some hosts (amd64, ia64) have an ABI that ignores the high bits
of the 64-bit register when passing 32-bit arguments.  Others
require the value to be properly sign-extended for the type.
I.e. "int32_t" must be sign-extended and "uint32_t" must be
zero-extended to 64-bits.

To effect this, extend the "sizemask" parameter to tcg_gen_callN
to include the signedness of the type of each parameter.  If the
tcg target requires it, extend each 32-bit argument into a 64-bit
temp and pass that to the function call.

This ABI feature is required by sparc64, ppc64 and s390x.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>