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What does push offset mean?

What does push offset mean?

So, OFFSET means simply that the offset of the address of some variable “Hello_Wo.??_ C@_0M@KPLPPDAC@H” is pushed in the stack. This directive is from the MASM syntax where “push variable” means push the value of the variable and “push offset variable” means push the offset of the variable.

What is push in x86?

The push instruction places its operand onto the top of the hardware supported stack in memory. Specifically, push first decrements ESP by 4, then places its operand into the contents of the 32-bit location at address [ESP].

What does x86 call do?

CALL stores the address of the next instruction on the stack, and starts executing the first instruction at the address specified. When the CPU encouters the accompanying RET instruction (or RETF, for a far call), it retrieves the address to return to from the stack, and continues execution from there.

What are the push instructions in x86 assembly?

Description 1 The push instruction is used to push values on the stack. 2 The pusha instruction is used to push the 16-bit registers in the following order: AX, CX, DX, BX, SP, BP, SI, DI 3 The pushad instruction is used to push the 32-bit registers in the following order: EAX, ECX, EDX, EBX, ESP, EBP, ESI,… More

What does offset mean in x86 assembly language?

Answer Wiki. 3 Answers. “Offset” is an assembler directive in x86 assembly language. It actually means “address” and is a way of handling the overloading of the “mov” instruction.

How do you push 32-bit registers in x86?

The pushad instruction is used to push the 32-bit registers in the following order: EAX, ECX, EDX, EBX, ESP, EBP, ESI, EDI; Syntax push value pusha pushad Examples Example 1 push 0xdebf ; push a value to the stack pop eax ; eax is now 0xdebf Example 2; swap content of registers push eax mov eax, ebx pop ebx Example 3

How is the stack pointer decremented in x86?

ESP (the stack pointer) is decremented by push since the x86 stack grows down — i.e. the stack grows from high addresses to lower addresses. The pop instruction removes the 4-byte data element from the top of the hardware-supported stack into the specified operand (i.e. register or memory location).