A mechanism is disclosed for detecting underflow conditions for speculative floating-point operations. A floating-point status register includes a status flag which is set when a result generated by a floating-point instruction is 'tiny'. The status flag is cleared, all exceptions are masked, and the instruction is executed speculatively. The 'tiny' exception flag is read to determine whether the speculatively executed instruction should raise an unmasked underflow exception. The exception may be raised if the processor reaches a point of registration associated with the instruction. The exception may be ignored if this point is not reached.