What are lock instructions?
What are lock instructions?
4 Answers
- LOCK is not an instruction itself: it is an instruction prefix, which applies to the following instruction.
- This code copies the address of the variable to be incremented off the stack into the ecx register, then it does lock incl (ìx) to atomically increment that variable by 1.
What is the lock prefix?
The LOCK prefix is typically used with the BTS instruction to perform a read-modify-write operation on a memory location in shared memory environment. The integrity of the LOCK prefix is not affected by the alignment of the memory field. Memory locking is observed for arbitrarily misaligned fields.
What is lock processor?
A CPU lock or CPU locking is the process of locking down a CPU’s clock multiplier, either permanently or until the lock is removed. The main purpose of this is to prevent users from overclocking the CPUs, making them operate in conditions that they were not designed for, and then possibly damaging them.
What is IA 32 instruction set?
IA-32 (short for “Intel Architecture, 32-bit”, sometimes also called i386) is the 32-bit version of the x86 instruction set architecture, designed by Intel and first implemented in the 80386 microprocessor in 1985.
What are the parts to a door lock?
Parts of a door lock
- Trim: Sometimes called a rose, the trim is a decorative plate attached to the door under the knob or lever.
- Deadbolt:
- Escutcheon:
- Faceplate.
- Backplate:
- Latch bolt:
- Spindle:
- Strike plate:
Are x86 instructions Atomic?
x86 guarantees that aligned loads and stores up to 64 bits are atomic, but not wider accesses.
Which are the registers used by the multiply and divide instructions?
Description. The single-operand form of imul executes a signed multiply of a byte, word, or long by the contents of the AL, AX, or EAX register and stores the product in the AX, DX:AX or EDX:EAX register respectively.
Which instruction is often used to set the flags just before a jump instruction?
This is performed by a set of jump instructions j depending upon the condition….Conditional Jump.
| Instruction | Description | Flags tested |
|---|---|---|
| JO | Jump If Overflow | OF |
| JNO | Jump If No Overflow | OF |
| JP/JPE | Jump Parity or Jump Parity Even | PF |
| JNP/JPO | Jump No Parity or Jump Parity Odd | PF |
What is the difference between a locked and unlocked Intel processor?
Answer: An unlocked CPU comes with an unlocked clock multiplier, meaning that it can be overclocked quickly and easily. A locked CPU cannot be overclocked this way and can only be overclocked via BCLK overclocking. One such feature that many will focus on when choosing a CPU is whether the CPU is locked or unlocked.
What is 64-bit instruction set?
The x64 architecture is a backwards-compatible extension of x86. It provides a legacy 32-bit mode, which is identical to x86, and a new 64-bit mode. The term “x64” includes both AMD 64 and Intel64. The instruction sets are close to identical.
What is IA32 64 Intel CPU?
Intel® 64 Architecture refers to systems based on IA-32 architecture processors which have 64-bit architectural extensions, for example, Intel® CoreTM2 processor family), running a 64-bit operating system such as Microsoft Windows XP* Professional x64 Edition or Microsoft Windows Vista* x64.
What is the point of the LOCK prefix of Intel instruction?
LOCK prefix of Intel instruction. What is the point? Ask Question Asked9 years, 2 months ago Active4 years, 11 months ago Viewed12k times 6 9 I read the Intel manual and found there is a lock prefix for instructions, which can prevent processors writing to the same memory location at the same time.
What is x86 instruction set in microprocessor?
x86 integer instructions. This is the full 8086/8088 instruction set of Intel. Most if not all of these instructions are available in 32-bit mode; they just operate on 32-bit registers (eax, ebx, etc.) and values instead of their 16-bit (ax, bx, etc.) counterparts.
How many instructions are in the 8086 instruction set?
Below is the full 8086/8088 instruction set of Intel (81 instructions total). Most if not all of these instructions are available in 32-bit mode; they just operate on 32-bit registers ( eax, ebx, etc.) and values instead of their 16-bit ( ax, bx, etc.) counterparts.
