1 // an implementation of sqrtf for Thumb using hardware VFP instructions
2 
3 #include <math.h>
4 
sqrtf(float x)5 float sqrtf(float x) {
6     asm volatile (
7             "vsqrt.f32  %[r], %[x]\n"
8             : [r] "=t" (x)
9             : [x] "t"  (x));
10     return x;
11 }
12