Given by the opt guide(A72), cmgt(register) and cmgt(zero) have the same latency. The later can save a mov instruction, from core to floating-point register.

movi v16.4s, #0x0
cmgt v16.4s, v17.4s, v16.4s

The code above could be optimized to

cmgt v16.4s, v17.4s, #0x0
 

test case:
```
 import jdk.incubator.vector.*;
 
public class TestCmpZero {
     public static final int a = 0;
     public static VectorMask<Integer> testZero(IntVector va) {
        return va.compare(VectorOperators.LT, a);
      }
    public static void main(String[] args) {
        final IntVector va = IntVector.broadcast(IntVector.SPECIES_128, 1);
          for (int i = 0; i < 200000; i++) {
              testZero(va);
          }
      }
 }

```