F2XM1
Usage: F2XM1 Modifies flags: None
Computes the exponential value of 2 to the power of the source operand minus 1. The source operand is located in register ST(0) and the result is also stored in ST(0). The value of the source operand must lie in the range -1.0 to +1.0. If the source value is outside this range, the result is undefined.
Calculate 2**X-1
F2XM1 ; D9 F0 [8086,FPU]
F2XM1 raises 2 to the power of ST0, subtracts one, and stores the result back into ST0. The initial contents of ST0 must be a number in the range -1.0 to +1.0.
EXAMPLE:
f2mfx1