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INSTRUCTION SET REFERENCE
FST/FSTPĀStore Real (Continued)
FPU Flags Affected
C1
Set to 0 if stack underflow occurred.
Indicates rounding direction of if the floating-point inexact exception (#P)
is generated: 0 = not roundup; 1 = roundup.
C0, C2, C3
Undefined.
Floating-Point Exceptions
#IS
Stack underflow occurred.
#IA
Source operand is an sNaN value or unsupported format.
#U
Result is too small for the destination format.
#O
Result is too large for the destination format.
#P
Value cannot be represented exactly in destination format.
Protected Mode Exceptions
#GP(0)
If the destination is located in a nonwritable segment.
If a memory operand effective address is outside the CS, DS, ES, FS, or
GS segment limit.
If the DS, ES, FS, or GS register is used to access memory and it contains
a null segment selector.
#SS(0)
If a memory operand effective address is outside the SS segment limit.
#NM
EM or TS in CR0 is set.
#PF(fault-code)If a page fault occurs.
#AC(0)
If alignment checking is enabled and an unaligned memory reference is
made while the current privilege level is 3.
Real-Address Mode Exceptions
#GP
If a memory operand effective address is outside the CS, DS, ES, FS, or
GS segment limit.
#SS
If a memory operand effective address is outside the SS segment limit.
#NM
EM or TS in CR0 is set.
