
Volume 4: Base IA-32 Instruction Reference
4:89
DEC—Decrement by 1
Description
Subtracts 1 from the operand, while preserving the state of the CF flag. The source
operand can be a register or a memory location. This instruction allows a loop counter
to be updated without disturbing the CF flag. (Use a SUB instruction with an immediate
operand of 1 to perform a decrement operation that does updates the CF flag.)
Operation
DEST
DEST - 1;
Flags Affected
The CF flag is not affected. The OF, SF, ZF, AF, and PF flags are set according to the
result.
Additional Itanium System Environment Exceptions
Itanium Reg Faults NaT Register Consumption Abort.
Itanium Mem FaultsVHPT Data Fault, Nested TLB Fault, Data TLB Fault, Alternate Data
TLB Fault, Data Page Not Present Fault, Data NaT Page Consumption
Abort, Data Key Miss Fault, Data Key Permission Fault, Data Access
Rights Fault, Data Access Bit Fault, Data Dirty Bit Fault
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 contains a null segment selector.
#SS(0)
If a memory operand effective address is outside the SS segment
limit.
#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.
Opcode
Instruction
Description
FE /1
DEC
r/m8
Decrement
r/m8
by 1
FF /1
DEC
r/m16
Decrement
r/m16
by 1
FF /1
DEC
r/m32
Decrement
r/m32
by 1
48+rw
DEC
r16
Decrement
r16
by 1
48+rd
DEC
r32
Decrement
r32
by 1
Содержание ITANIUM ARCHITECTURE
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Страница 7: ...402 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 199: ...4 192 Volume 4 Base IA 32 Instruction Reference FWAIT Wait See entry for WAIT ...
Страница 269: ...4 262 Volume 4 Base IA 32 Instruction Reference LES Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 270: ...Volume 4 Base IA 32 Instruction Reference 4 263 LFS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 273: ...4 266 Volume 4 Base IA 32 Instruction Reference LGS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 288: ...Volume 4 Base IA 32 Instruction Reference 4 281 LSS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 352: ...Volume 4 Base IA 32 Instruction Reference 4 345 ROL ROR Rotate See entry for RCL RCR ROL ROR ...
Страница 368: ...Volume 4 Base IA 32 Instruction Reference 4 361 SHL SHR Shift Instructions See entry for SAL SAR SHL SHR ...
Страница 373: ...4 366 Volume 4 Base IA 32 Instruction Reference SIDT Store Interrupt Descriptor Table Register See entry for SGDT SIDT ...
Страница 589: ...4 582 Volume 4 IA 32 SSE Instruction Reference ...
Страница 590: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 Index ...
Страница 591: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 603: ...INDEX Index 12 Index for Volumes 1 2 3 and 4 ...
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