The 32-bit product should be sign-extended, not zero-extended.
Fixes: ea96b37464
Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20190912183058.17947-1-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>