Intel 253666-024US Benutzerhandbuch
3-390 Vol. 2A
FSTCW/FNSTCW—Store x87 FPU Control Word
INSTRUCTION SET REFERENCE, A-M
Protected Mode Exceptions
#GP(0)
If the destination is located in a non-writable segment.
If a memory operand effective address is outside the CS, DS,
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
CR0.EM[bit 2] or CR0.TS[bit 3] = 1.
#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.
#UD
If the LOCK prefix is used.
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
CR0.EM[bit 2] or CR0.TS[bit 3] = 1.
#UD
If the LOCK prefix is used.
Virtual-8086 Mode Exceptions
#GP(0)
If a memory operand effective address is outside the CS, DS,
ES, FS, or GS segment limit.
#SS(0)
If a memory operand effective address is outside the SS
segment limit.
#NM
CR0.EM[bit 2] or CR0.TS[bit 3] = 1.
#PF(fault-code)
If a page fault occurs.
#AC(0)
If alignment checking is enabled and an unaligned memory
reference is made.
#UD
If the LOCK prefix is used.
Compatibility Mode Exceptions
Same exceptions as in protected mode.
64-Bit Mode Exceptions
#SS(0)
If a memory address referencing the SS segment is in a non-
canonical form.
#GP(0)
If the memory address is in a non-canonical form.