For example, here is a line of machine code: The first few bits (10110) are an instruction to copy a value into a register. This is performed by a set of jump instructions j depending upon the condition. Let us discuss the CMP instruction before discussing the conditional instructions. This is performed by the JMP instruction. Inversely, the results of the computation might need to be stored in memory, where the array resides. It does not disturb the destination or source operands. It is used along with the conditional jump instruction for decision making. Conditional execution in assembly language is accomplished by several looping and branching instructions. Transfer of control may be forward, to execute a new set of instructions or backward, to re-execute the same steps. These can be arith- metic (sum, subtraction, multiplication), … The instruction statements are the working part of the language andare divided into the following three groups: Machine instructions.

If some specified condition is satisfied in conditional jump, the control flow is transferred to a target instruction. Lab Objective. In this lab, we will learn some basic ARM assembly language instructions and write a simple programs in assembly language. Conditional execution in assembly language is accomplished by several looping and branching instructions. CMP is often used for comparing whether a counter value has reached the number of times a loop needs to be run. The three variables num1, num2 and num3 have values 47, 22 and 31, respectively −, When the above code is compiled and executed, it produces the following result −.

Data processing instructions manipulate the data within the registers. MASM uses the standard Intel syntax for writing x86 assembly code. This instruction basically subtracts one operand from the other for comparing whether the operands are equal or not. Consider the following typical condition −. The destination operand could be either in register or in memory. The syntax for the MUL/IMUL instructions is as follows − MUL/IMUL multiplier ARM Assembly Instructions. The one we will use in CS216 is the Microsoft Macro Assembler (MASM) assembler. A microprocessor is a mechanical calculator. Both instructions affect the Carry and Overflow flag. Macro instructions.

There are numerous conditional jump instructions depending upon the condition and data. Figure 1 shows the 32 bits found in an ARM data-processing instruction; each bit has a specific purpose, either individually or as part of a group. Syntax. Conditional execution is observed in two scenarios −. The rest of it (01100001) is the value which is to be copied. Since most of the instructions we'll go over are for data operations, I've grabbed the data-processing instruction out of the ARMV7 manual. The variables are double-digit variables. instructions and assembler directives. Conditional execution is observed in two scenarios − Let us discuss the CMP instruction before discussing the conditional instructions. Each instruction consists of an operation code (opcode). The MUL (Multiply) instruction handles unsigned data and the IMUL (Integer Multiply) handles signed data.