Overview Why you should care about the ISA Instruction sets in the Arm architecture Instruction set resources Simple sequential execution Registers in AArch64 - general-purpose registers Registers in AArch64 - other registers Registers in AArch64 - system registers Data processing - arithmetic and logic operations Data processing - floating point Data processing - bit manipulation Data processing - extension and saturation Data processing - format conversion Data processing - vector data Loads and stores Loads and stores - size Loads and stores - zero and sign extension Loads and stores - addressing Loads and stores - load pair and store pair Loads and stores - using floating point registers Program flow Program flow - loops and decisions Program flow - generating condition code Program flow - conditional select instructions Function calls Procedure Call Standard System calls Check your knowledge Related information Next steps
Program flow
Ordinarily, a processor executes instructions in program order. This means that a processor executes instructions in the same order that they are set in memory. One way to change this order is to use branch instructions. Branch instructions change the program flow and are used for loops, decisions and function calls.
The A64 instruction set also has some conditional branch instructions. These are instructions that change the way they execute, based on the results of previous instructions.
Note: Armv8.3-A and Armv8.5-A introduced instructions to protect against return-oriented programming and jump-oriented programming.