Which is a more efficient x86 assembly language instruction to increment an integer by 1 Inc or add?

ADD is not always faster than INC , but it is almost always at least as fast (there are a few corner cases on certain older micro-architectures, but they are exceedingly rare), and sometimes significantly faster.

What does pusha do in assembly?

PUSHA/PUSHAD–Push All General-Purpose Registers Pushes the contents of the general-purpose registers onto the stack.

What are the two codes x86 registers?

Data register (DX). Used in arithmetic operations and I/O operations. Base register (BX). Used as a pointer to data (located in segment register DS, when in segmented mode).

What are the two main parts of an x86 instruction called?

The x86 instruction set includes string load, store, move, scan and compare instructions ( lods , stos , movs , scas and cmps ) which perform each operation to a specified size ( b for 8-bit byte, w for 16-bit word, d for 32-bit double word) then increments/decrements (depending on DF, direction flag) the implicit …

What registers does pusha push?

PUSHA pushes all 16-bit general-purpose registers onto the stack. This instruction is present on the 286 and later CPUs and is not available in the 8086/8088. The registers are pushed in this order: AX, CX, DX, BX, SP, BP, SI, DI.

Which other instruction can be used instead of PUSH A?

For example, push rax has a single-byte encoding of 0x50 . But yes you can emulate it using other instructions like sub rsp, 8 and a mov store.

What number representation is used by today’s x86 processors?

In the 1980s and early 1990s, when the 8088 and 80286 were still in common use, the term x86 usually represented any 8086-compatible CPU. Today, however, x86 usually implies a binary compatibility also with the 32-bit instruction set of the 80386.

Is x64 better than x86?

Is x64 faster than x86? Yes, x64 is faster than x86 systems as they can allocate a lot more RAM and has parallel processing with a more significant 64-bit memory and data bus. It also has larger registers, and the overall performance with 64-bit OS and processors is a lot faster than 32-bit systems.

Is push and pop a register or not?

The explicit operand for push and pop is r/m, not just register, so you can push dword [esi]. Or even pop dword [esp]to load and then store the same value back to the same address. (github.com/HJLebbink/asm-dude/wiki/POP). I only mention this because you say “not necessarily a register”.

Are Pusha and Popa functionally equivalent?

Yes, pusha and popa are functionally equivalent, if only because they push/pop all registers. However, is it necessary to do so for a simple DOS Interrupt call?

What is a PUSH instruction in x86?

A push is a single instruction in x86, which does two things internally. Decrement the ESP register by the size of pushed value. Store the pushed value at current address of ESP register.

What is the difference between push and pop in C++?

pushing a value (not necessarily stored in a register) means writing it to the stack. popping means restoring whatever is on top of the stack into a register. Those are basic instructions: The explicit operand for push and pop is r/m, not just register, so you can push dword [esi].

https://www.youtube.com/watch?v=vcfQVwtoyHY