github.com/afumu/libc@v0.0.6/musl/src/math/i386/sqrtl.c (about)

     1  #include <math.h>
     2  
     3  long double sqrtl(long double x)
     4  {
     5  	__asm__ ("fsqrt" : "+t"(x));
     6  	return x;
     7  }