Add popcount builtin function for OpenCL v1.2

OpenCL v1.2 defines the builtin popcount, which counts the number of
one bits in the argument.

Extra care is taken to avoid sign extension in casting from the smaller
signed types (char,short) to uint, the argument of __builting_popcount().

This commit enables the Khronos conformance test to PASS:
  % test_integer_ops popcount

Signed-off-by: Gil Pitney <gil.pitney@linaro.org>

0 files changed, 0 insertions, 0 deletions