A.5.91 FLDENV: Load Floating-Point Environment
FLDENV mem ; D9 /4 [8086,FPU]
FLDENV loads the FPU operating environment (control word, status word,
tag word, instruction pointer, data pointer and last opcode) from
memory. The memory area is 14 or 28 bytes long, depending on the CPU
mode at the time. See also FSTENV (section A.5.104).