[PATCH] [AArch64] Add nvcast patterns for v4f16 and v8f16

[Pirama Arumuga Nainar]

According to AArchISelLowering::LowerBUILD_VECTOR, nvcast from v2f32, v4f32, v2f64 can also be generated.  However, I couldn't create the correct constant pattern that creates these ops.

For completeness, I can add patterns for v2f32 to v4f16 and also v4f32 and v2f64 to v8f16, but I might need some assistance adding tests for them, though.


http://reviews.llvm.org/D9201

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/