What is IDIV in assembly language?
Description. idiv executes signed division. idiv divides a 16-, 32-, or 64-bit register value (dividend) by a register or memory byte, word, or long (divisor). The size of the divisor (8-, 16- or 32-bit operand) determines the particular register used as the dividend, quotient, and remainder.
What is difference between div and IDIV instruction?
Using Division Instructions: The DIV instruction divides unsigned numbers, and IDIV divides signed numbers. Both return a quotient and a remainder.
What is EDX in assembly language?
A feature of assembly language is that each line in the source code usually contains a single instruction to the processor, for example MOV EAX,EDX will move the content of the EDX register into the EAX register. Here the “MOV” instruction is called a “mnemonic”.
What is the function of IDIV instruction?
IDIV is an arithmetic instruction that performs a division operation between two signed numbers. The source operand in the instruction is a signed divisor. It can be specified using any addressing mode except immediate mode of addressing.
How does Div work in 8086?
8086 DIV Instruction ( Unsigned Operands) The DIV instruction performs the division of two unsigned operands. The denominator resides in a source operand and it should not be immediate. However, it can be register or a memory location.
How does Div work in MASM?
Well, it is simple: DIV does divide the 64-bit value of EDX(bits 63-32):EAX(bits 31-0) by the operand of EBX (32-bits). Executing DIV EBX means dividing EDX:EAX (64-bit) by EBX (32-bit).
What does mov mean in assembly?
Data Movement Instructions
Data Movement Instructions mov — Move (Opcodes: 88, 89, 8A, 8B, 8C, 8E.) The mov instruction copies the data item referred to by its second operand (i.e. register contents, memory contents, or a constant value) into the location referred to by its first operand (i.e. a register or memory).
What is BX AX Al and CX register?
For example, in multiplication operation, one operand is stored in EAX or AX or AL register according to the size of the operand. BX is known as the base register, as it could be used in indexed addressing. CX is known as the count register, as the ECX, CX registers store the loop count in iterative operations.
What is IDIV instruction in C?
Description The idiv instruction divides the contents of the 64-bit integer EDX:EAX by the specified operand value. The quotient result of the division is stored into EAX The remainder is placed in EDX.
What does the idivq instruction Do?
The idivq instruction divides a 128-bit integer ( rdx:rax) by the given source operand. rax holds the lower 64-bits of the dividend.
What is the value of RDX in iDiv?
The first part of Mysticials answer is correct, idiv does a 128/64 bit division, so the value of rdx, which holds the upper 64 bit from the dividend must not contain a random value. But a zero extension is the wrong way to go.