rs6000.c: Add handling for early expansion of vector multiply builtins.

rs6000.c: Add handling for early expansion of vector multiply builtins.

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

        *  config/rs6000/rs6000.c: Add handling for early expansion of
        vector multiply builtins.

[gcc/testsuite]

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

        *  gcc.dg/vmx/mult-even-odd-be-order.c : Mark
        variables as volatile.
        *  gcc.target/powerpc/fold-vec-mult-char.c : New.
        *  gcc.target/powerpc/fold-vec-mult-float.c : New.
        *  gcc.target/powerpc/fold-vec-mult-floatdouble.c : New.
        *  gcc.target/powerpc/fold-vec-mult-int.c : New.
        *  gcc.target/powerpc/fold-vec-mult-int128-p8.c : New.
        *  gcc.target/powerpc/fold-vec-mult-int128-p9.c : New.
        *  gcc.target/powerpc/fold-vec-mult-longlong.c : New.
        *  gcc.target/powerpc/fold-vec-mult-short.c : New.

From-SVN: r243807