9.9 Exception Summary 异常汇总
Table 9-6 summarizes the exceptions recognized by the 386.
Table 9-6. Exception Summary
Description Interrupt Return Address Exception Function That Can Generate
Number Points to Type the Exception
Faulting
Instruction
Divide error 0 YES FAULT DIV, IDIV
Debug exceptions 1
Some debug exceptions are traps and some are faults. The exception
handler can determine which has occurred by examining DR6. (Refer to Chapter 12.)
Some debug exceptions are traps and some are faults. The exception
handler can determine which has occurred by examining DR6. (Refer to Chapter 12.) Any instruction
Breakpoint 3 NO TRAP One-byte INT 3
Overflow 4 NO TRAP INTO
Bounds check 5 YES FAULT BOUND
Invalid opcode 6 YES FAULT Any illegal instruction
Coprocessor not available 7 YES FAULT ESC, WAIT
Double fault 8 YES ABORT Any instruction that can
generate an exception
Coprocessor Segment
Overrun 9 NO ABORT Any operand of an ESC
instruction that wraps around
the end of a segment.
Invalid TSS 10 YES FAULT
An invalid-TSS fault is not restartable if it occurs during the
processing of an external interrupt. JMP, CALL, IRET, any interrupt
Segment not present 11 YES FAULT Any segment-register modifier
Stack exception 12 YES FAULT Any memory reference thru SS
General Protection 13 YES FAULT/ABORT
All GP faults are restartable. If the fault occurs while attempting to
vector to the handler for an external interrupt, the interrupted program is
restartable, but the interrupt may be lost. Any memory reference or code
fetch
Page fault 14 YES FAULT Any memory reference or code
fetch
Coprocessor error 16 YES FAULT
Coprocessor errors are reported as a fault on the first ESC or WAIT
instruction executed after the ESC instruction that caused the error. ESC, WAIT
Two-byte SW Interrupt 0-255 NO TRAP INT n
9.10 Error Code Summary 错误代码汇总
Table 9-7 summarizes the error information that is available with each exception.
Table 9-7. Error-Code Summary
Description Interrupt Error Code
Number
Divide error 0 No
Debug exceptions 1 No
Breakpoint 3 No
Overflow 4 No
Bounds check 5 No
Invalid opcode 6 No
Coprocessor not available 7 No
System error 8 Yes (always 0)
Coprocessor Segment Overrun 9 No
Invalid TSS 10 Yes
Segment not present 11 Yes
Stack exception 12 Yes
General protection fault 13 Yes
Page fault 14 Yes
Coprocessor error 16 No
Two-byte SW interrupt 0-255 No