1*c9945492SAndroid Build Coastguard Worker #include "libm.h" 2*c9945492SAndroid Build Coastguard Worker 3*c9945492SAndroid Build Coastguard Worker #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 nexttoward(double x,long double y)4*c9945492SAndroid Build Coastguard Workerdouble nexttoward(double x, long double y) 5*c9945492SAndroid Build Coastguard Worker { 6*c9945492SAndroid Build Coastguard Worker return nextafter(x, y); 7*c9945492SAndroid Build Coastguard Worker } 8*c9945492SAndroid Build Coastguard Worker #else nexttoward(double x,long double y)9*c9945492SAndroid Build Coastguard Workerdouble nexttoward(double x, long double y) 10*c9945492SAndroid Build Coastguard Worker { 11*c9945492SAndroid Build Coastguard Worker union {double f; uint64_t i;} ux = {x}; 12*c9945492SAndroid Build Coastguard Worker int e; 13*c9945492SAndroid Build Coastguard Worker 14*c9945492SAndroid Build Coastguard Worker if (isnan(x) || isnan(y)) 15*c9945492SAndroid Build Coastguard Worker return x + y; 16*c9945492SAndroid Build Coastguard Worker if (x == y) 17*c9945492SAndroid Build Coastguard Worker return y; 18*c9945492SAndroid Build Coastguard Worker if (x == 0) { 19*c9945492SAndroid Build Coastguard Worker ux.i = 1; 20*c9945492SAndroid Build Coastguard Worker if (signbit(y)) 21*c9945492SAndroid Build Coastguard Worker ux.i |= 1ULL<<63; 22*c9945492SAndroid Build Coastguard Worker } else if (x < y) { 23*c9945492SAndroid Build Coastguard Worker if (signbit(x)) 24*c9945492SAndroid Build Coastguard Worker ux.i--; 25*c9945492SAndroid Build Coastguard Worker else 26*c9945492SAndroid Build Coastguard Worker ux.i++; 27*c9945492SAndroid Build Coastguard Worker } else { 28*c9945492SAndroid Build Coastguard Worker if (signbit(x)) 29*c9945492SAndroid Build Coastguard Worker ux.i++; 30*c9945492SAndroid Build Coastguard Worker else 31*c9945492SAndroid Build Coastguard Worker ux.i--; 32*c9945492SAndroid Build Coastguard Worker } 33*c9945492SAndroid Build Coastguard Worker e = ux.i>>52 & 0x7ff; 34*c9945492SAndroid Build Coastguard Worker /* raise overflow if ux.f is infinite and x is finite */ 35*c9945492SAndroid Build Coastguard Worker if (e == 0x7ff) 36*c9945492SAndroid Build Coastguard Worker FORCE_EVAL(x+x); 37*c9945492SAndroid Build Coastguard Worker /* raise underflow if ux.f is subnormal or zero */ 38*c9945492SAndroid Build Coastguard Worker if (e == 0) 39*c9945492SAndroid Build Coastguard Worker FORCE_EVAL(x*x + ux.f*ux.f); 40*c9945492SAndroid Build Coastguard Worker return ux.f; 41*c9945492SAndroid Build Coastguard Worker } 42*c9945492SAndroid Build Coastguard Worker #endif 43