rs6000.c (rs6000_gimple_fold_builtin): Add handling for early expansion of vector subtract builtins.


2016-12-19  Will Schmidt  <will_schmidt@vnet.ibm.com>

        * config/rs6000/rs6000.c (rs6000_gimple_fold_builtin): Add handling for
        early expansion of vector subtract builtins.
    
[gcc/testsuite]

2016-12-19  Will Schmidt  <will_schmidt@vnet.ibm.com>

      * gcc.target/powerpc/fold-vec-sub-char.c: New.
      * gcc.target/powerpc/fold-vec-sub-float.c: New.
      * gcc.target/powerpc/fold-vec-sub-floatdouble.c: New.
      * gcc.target/powerpc/fold-vec-sub-int.c: New.
      * gcc.target/powerpc/fold-vec-sub-int128.c: New.
      * gcc.target/powerpc/fold-vec-sub-longlong.c: New.
      * gcc.target/powerpc/fold-vec-sub-short.c: New.

From-SVN: r243806