GLM_FUNC_QUALIFIER double nextafter()

in endless-tunnel/app/src/main/cpp/glm/gtc/ulp.inl [141:189]
47 lines of code
23 McCabe index (conditional complexity)

	GLM_FUNC_QUALIFIER double nextafter(double x, double y)
	{
		volatile double t;
		glm::detail::int32 hx, hy, ix, iy;
		glm::detail::uint32 lx, ly;

		GLM_EXTRACT_WORDS(hx, lx, x);
		GLM_EXTRACT_WORDS(hy, ly, y);
		ix = hx & 0x7fffffff;             // |x| 
		iy = hy & 0x7fffffff;             // |y| 

		if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) ||   // x is nan
			((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0))     // y is nan
			return x+y;
		if(x==y) return y;              // x=y, return y
		if((ix|lx)==0) {                        // x == 0 
			GLM_INSERT_WORDS(x, hy & 0x80000000, 1);    // return +-minsubnormal
			t = x*x;
			if(t==x) return t; else return x;   // raise underflow flag 
		}
		if(hx>=0) {                             // x > 0 
			if(hx>hy||((hx==hy)&&(lx>ly))) {    // x > y, x -= ulp 
				if(lx==0) hx -= 1;
				lx -= 1;
			} else {                            // x < y, x += ulp
				lx += 1;
				if(lx==0) hx += 1;
			}
		} else {                                // x < 0 
			if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){// x < y, x -= ulp
				if(lx==0) hx -= 1;
				lx -= 1;
			} else {                            // x > y, x += ulp
				lx += 1;
				if(lx==0) hx += 1;
			}
		}
		hy = hx&0x7ff00000;
		if(hy>=0x7ff00000) return x+x;  // overflow
		if(hy<0x00100000) {             // underflow
			t = x*x;
			if(t!=x) {          // raise underflow flag
				GLM_INSERT_WORDS(y,hx,lx);
				return y;
			}
		}
		GLM_INSERT_WORDS(x,hx,lx);
		return x;
	}