[ARM64] Enable feature predicates for NEON / FP / CRYPTO.

AArch64 has feature predicates for NEON, FP and CRYPTO instructions.
This allows the compiler to generate code without using FP, NEON
or CRYPTO instructions.

llvm-svn: 206949

1 files changed, 10 insertions, 6 deletions

diff --git a/llvm/lib/Target/ARM64/ARM64TargetTransformInfo.cpp b/llvm/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
index f4116891809..40228021e42 100644
--- a/llvm/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
+++ b/llvm/lib/Target/ARM64/ARM64TargetTransformInfo.cpp
@@ -87,16 +87,20 @@ public:
   /// @{
 
   unsigned getNumberOfRegisters(bool Vector) const override {
-    if (Vector)
-      return 32;
-
+    if (Vector) {
+      if (ST->hasNEON())
+        return 32;
+      return 0;
+    }
     return 31;
   }
 
   unsigned getRegisterBitWidth(bool Vector) const override {
-    if (Vector)
-      return 128;
-
+    if (Vector) {
+      if (ST->hasNEON())
+        return 128;
+      return 0;
+    }
     return 64;
   }