[AArch64] Add a fp128 shuffle test. NFC

These legalize to scalar types, so it's useful to have a test case that
covers them.

Author: davemgreen

llvm/test/Analysis/CostModel/AArch64/shuffle-other.ll

@@ -15,6 +15,7 @@ define void @shuffle() {
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %v15 = shufflevector <4 x i32> undef, <4 x i32> undef, <4 x i32> <i32 1, i32 3, i32 2, i32 0>
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v16 = shufflevector <2 x float> undef, <2 x float> undef, <2 x i32> <i32 1, i32 0>
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %v17 = shufflevector <4 x float> undef, <4 x float> undef, <4 x i32> <i32 1, i32 3, i32 2, i32 0>
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %v18 = shufflevector <2 x fp128> undef, <2 x fp128> undef, <2 x i32> <i32 1, i32 0>
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
   %v7 = shufflevector <2 x i8> undef, <2 x i8> undef, <2 x i32> <i32 1, i32 0>
@@ -33,6 +34,8 @@ define void @shuffle() {
   %v16 = shufflevector <2 x float> undef, <2 x float> undef, <2 x i32> <i32 1, i32 0>
   %v17 = shufflevector <4 x float> undef, <4 x float> undef, <4 x i32> <i32 1, i32 3, i32 2, i32 0>
 
+  %v18 = shufflevector <2 x fp128> undef, <2 x fp128> undef, <2 x i32> <i32 1, i32 0>
+
   ret void
 }