Bug swiftshader:6

Change-Id: I6443479e34b0819de45196c61a2e9fc0bf0e84d7
Reviewed-on: https://swiftshader-review.googlesource.com/7752Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-on: https://swiftshader-review.googlesource.com/8134Reviewed-by: Alexis Hétu <sugoi@google.com>