Bug swiftshader:23

Change-Id: Ifb2862e8358141f67a7974d3fa0a11e6fe41b904
Reviewed-on: https://swiftshader-review.googlesource.com/8290Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>