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You can often increase speed by omitting the WAIT instruction. The WAIT instruction has three functions:
a. The old 8087 processor requires a WAIT before every floating point instruction to make sure the coprocessor is ready to receive it.
b. WAIT is used for coordinating memory access between the floating point unit and the integer unit.
Examples:
b.1. FISTP [mem32]
WAIT ; wait for FPU to write before..
MOV EAX,[mem32] ; reading the result with the integer unit
b.2. FILD [mem32]
WAIT ; wait for FPU to read value..
MOV [mem32],EAX ; before overwriting it with integer unit
b.3. FLD QWORD PTR [ESP]
WAIT ; prevent an accidental interrupt from..
ADD ESP,8 ; overwriting value on stack
