Implement the SG instruction, which we emulate 'by hand' in the
exception handling code path.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-3-git-send-email-peter.maydell@linaro.org