FINIT
Usage: FINIT Modifies flags: See below
Sets the FPU control, status, tag, instruction pointer, and data pointer registers to their default states. The FPU control word is set to 037FH (round to nearest, all exceptions masked, 64-bit precision). The status word is cleared (no exception flags set, TOP is set to 0). The data registers in the register stack are left unchanged, but they are all tagged as empty (11B). Both the instruction and data pointers are cleared.
Initialize Floating-Point Unit
FINIT ; 9B DB E3 [8086,FPU]
FNINIT ; DB E3 [8086,FPU]
FINIT initializes the FPU to its default state. It flags all registers as empty, without actually changing their values, clears the top of stack pointer. FNINIT does the same, without first waiting for pending exceptions to clear.
As the FPU Stack can not hold more than eight Values, it is good programming practice to begin each chunk of FPU Instructions with a FINIT. Even more if your Code makes use of the new SSE extensions (MMX), that also use the FPU Registers.
FPU Flags Affected C0, C1, C2, C3 set to 0.
EXAMPLE:
finit