6CONSTANTS AND HIGH-LEVEL LANGUAGES
Some programmers may not realize it, but many CPUs do not treat constant and variable data identically at the machine code level. Most CPUs provide a special immediate addressing mode that allows a language translator to embed a constant value directly into a machine instruction rather than storing it in a memory location and accessing it as a variable. However, the CPU’s ability to represent constant data efficiently varies by CPU and, in fact, by the type of the data. By understanding how a CPU treats constant data at the machine code level, you can choose appropriate ways to represent constants in your HLL ...
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