Add a Subtarget feature 'v8fp' to the ARM backend.

llvm-svn: 185073
diff --git a/llvm/lib/Target/ARM/ARM.td b/llvm/lib/Target/ARM/ARM.td
index 134b83c..46928dc 100644
--- a/llvm/lib/Target/ARM/ARM.td
+++ b/llvm/lib/Target/ARM/ARM.td
@@ -45,6 +45,9 @@
 def FeatureVFP4   : SubtargetFeature<"vfp4", "HasVFPv4", "true",
                                      "Enable VFP4 instructions",
                                      [FeatureVFP3, FeatureFP16]>;
+def FeatureV8FP : SubtargetFeature<"v8fp", "HasV8FP",
+                                   "true", "Enable ARMv8 FP",
+                                   [FeatureVFP4]>;
 def FeatureD16    : SubtargetFeature<"d16", "HasD16", "true",
                                      "Restrict VFP3 to 16 double registers">;
 def FeatureHWDiv  : SubtargetFeature<"hwdiv", "HasHardwareDivide", "true",