霓虹灯代码运行比C代码慢得多?

I'm trying to implement Gauss-Newton optimization for a specific problem on iPhone ARM using NEON. The first function below is my original C function. The second is the NEON asm code I wrote. I ran each one 100,000 times and the NEON version takes 7-8 times longer than C version. I think the loading (vld1.32) is what takes most of the time. I experimented by taking removing some instructions.I'm trying to implement Gauss-Newton optimizati