Bug swiftshader:17

Change-Id: Idc1ea72f71770eb1378afb850d16026430adef60
Reviewed-on: https://swiftshader-review.googlesource.com/7754Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-on: https://swiftshader-review.googlesource.com/8135Reviewed-by: Alexis Hétu <sugoi@google.com>