Simplest way to check if two integers have same sign?

bool SameSign(int x, int y)
{
    return (x >= 0) ^ (y < 0);
}

template <typename valueType>
bool SameSign(typename valueType x, typename valueType y)
{
    return (x >= 0) ^ (y < 0);
}

return ((x<0) ==(y<0));

bool same = ((x ^ y) & >> 31) != 1;

bool same = !((x ^ y) & >> 31);

inline bool same_sign(int x, int y) {
    return (x^y) >= 0;
}

inline bool same_sign(int x, int y) {
    return (x<0) == (y<0);
}

#define SIGNBIT (~((unsigned int)-1 >> 1))
if ((x & SIGNBIT) == (y & SIGNBIT))
    // signs are the same

int mask = 1 << 31;
(a & mask) ^ (b & mask) < 0;

bool compare(T left, T right)
{
    return (left < 0) && (right < 0);
}

int sameSign(int a, int b) {
    return ~(a^b) & (1<<(sizeof(int)*8-1));
}

template <typename T> T sameSign(T a, T b) {
    return ~(a^b) & (1<<(sizeof(T)*8-1));
}