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FLDL2T

Calculates $st(1) = st(1) \times \log_2(st(0))$ and pops the value at $st(0)$ from the floating-point register stack.

The following table covers the source and destinations:

DO NOT support LOCK

This instruction is available in 64-bit mode and compatibility mode. It operates exclusively on the x87 FPU register stack; therefore, it is not applicable to XMM or YMM registers.

The instruction pops $st(0)$, which decrements the FPU TOP pointer. If the FPU stack is empty or contains only one element, a stack underflow exception may occur. Ensure that at least two values are present on the stack before execution to avoid #I. Precision and rounding control are governed by the FPU control word, and results may trigger #P, #U, or #O depending on the magnitude of the operands.