vulkan: implement neox mode for rope

kompute/op_rope.comp

@@ -63,6 +63,25 @@ void main() {
             out_[dst_data+1] = x0*sin_theta + x1*cos_theta;
         }
     } else {
-        // TODO: implement
+        const float inv_ndims = -1.f/pcs.n_dims;
+        for (uint ib = 0; ib < pcs.ne0/pcs.n_dims; ++ib) {
+            for (uint ic = 0; ic < pcs.n_dims; ic += 2) {
+                const float cos_theta = cos(theta);
+                const float sin_theta = sin(theta);
+
+                theta *= theta_scale;
+
+                const uint i0 = ib*pcs.n_dims + ic/2;
+
+                const uint src = uint((i3*pcs.nb03 + i2*pcs.nb02 + i1*pcs.nb01 + i0*pcs.nb00) / 4) + pcs.inOff; // Based from in
+                const uint dst_data = uint((i3*pcs.nb3  + i2*pcs.nb2  + i1*pcs.nb1  + i0*pcs.nb0) / 4) + pcs.outOff; // Based from out_
+
+                const float x0 = in_[src];
+                const float x1 = in_[src+pcs.n_dims/2];
+
+                out_[dst_data] = x0*cos_theta - x1*sin_theta;
+                out_[dst_data+pcs.n_dims/2] = x0*sin_theta + x1*cos_theta;
+            }
+        }
     }
 }