Search results
Results from the WOW.Com Content Network
Below is the full 8086/8088 instruction set of Intel (81 instructions total). [2] These instructions are also available in 32-bit mode, in which they operate on 32-bit registers (eax, ebx, etc.) and values instead of their 16-bit (ax, bx, etc.) counterparts.
x86 assembly language includes instructions for a stack-based floating-point unit (FPU). The FPU was an optional separate coprocessor for the 8086 through the 80386, it was an on-chip option for the 80486 series, and it is a standard feature in every Intel x86 CPU since the 80486, starting with the Pentium.
Whereas the 8086 was a 16-bit microprocessor, it used the same microarchitecture as Intel's 8-bit microprocessors (8008, 8080, and 8085). This allowed assembly language programs written in 8-bit to seamlessly migrate. [7] New instructions and features — such as signed integers, base+offset addressing, and self-repeating operations — were added.
In assembly languages these instructions are represented by mnemonics such as ADD/SUB, ADC/SBC (ADD/SUB including carry), SHL/SHR , ROL/ROR (bit rotates), RCR/RCL (rotate through carry), and so on. [2] The use of the carry flag in this manner enables multi-word add, subtract, shift, and rotate operations.
In computer programming, assembly language (alternatively assembler language [1] or symbolic machine code), [2] [3] [4] often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. [5]
Compared to typical software-implemented floating-point routines on an 8086 (without an 8087), the factors would be even larger, perhaps by another factor of 10 (i.e., a correct floating-point addition in assembly language may well consume over 1000 cycles).
The assembly instruction nop will most likely expand to mov r0, r0 which is encoded 0xE1A00000 (little-endian architecture). [4] ARM T32 (16 bit) NOP: 2 0xb000 Opcode for ADD SP, #0 - Add zero to the stack pointer (No operation). The assembly instruction nop will most likely expand to mov r8, r8 which is encoded 0x46C0. [5] ARM T32 (32 bit) NOP ...
In the x86 assembly language, the JMP instruction performs an unconditional jump. Such an instruction transfers the flow of execution by changing the program counter.There are a number of different opcodes that perform a jump; depending on whether the processor is in real mode or protected mode, and an override instruction is used, the instructions may take 16-bit, 32-bit, or segment:offset ...