FNSTSW

X87_ALU X87 x86_64

3 encoding forms.

X86_FNSTSW_X86_LEGACY_ONEBYTE_DF_75700
ax
X86_LEGACY DF FPU
XED_FNSTSW_X86_LEGACY_ONEBYTE_DD_716326
MEM0:w:mem16 REG0=XED_REG_X87STATUS:rw:SUPP
X86_LEGACY DD /7 X87
XED_FNSTSW_X86_LEGACY_ONEBYTE_DF_420511
REG0=XED_REG_AX:w:IMPL REG1=XED_REG_X87STATUS:rw:SUPP
X86_LEGACY DF /4 X87