Higher-Level Programming Languages vs. Assembly: Why Efficiency Often Takes a Back Seat
The question of whether to use higher-level programming languages like Java and C instead of assembly language, which is often perceived as faster, has intrigued developers for decades. While assembly language offers unparalleled performance, the choice of programming language is not solely determined by execution speed. Key factors like maintainability, portability across multiple platforms, and rapid development cycles often play critical roles in decision-making.
Personal Experience: Assembly vs. High-Level Languages
Back in the 80s, I had the unique opportunity to write production code using assembly language on systems like the Atari and an 800-byte assembly program on a PDP-11. Despite the assembly code being faster in execution, it took considerably longer to develop, around six months, compared to a few weeks using a high-level language. The assembly code could execute in seconds, whereas the basic version would take minutes. This highlights the fundamental trade-off between development time and execution speed.
Development Speed vs. Execution Speed
In today's world, computer time is inexpensive, and programmer time is costly. It's crucial to strike a balance between these factors. While high-level languages like Java and C are slower in execution, they offer significant advantages in development speed and code readability. Getting a working program up and running much faster is a significant benefit, especially in today's fast-paced development environments.
Historic Context: The Evolution of Computing
Back in the late 70s and early 80s, computing was vastly different. Core memory, which was both expensive and limited in capacity, made assembly language a necessity. For instance, in 1974, the PDP-11 had 28k words of 16-bit memory and execution time of 1.2 microseconds per instruction. Contrast this with modern PCs that boast gigabytes of memory and processors running at 2-3 GHz, completing operations in a fraction of a second. With memory and performance so much more accessible today, the need for assembly code has significantly diminished.
Dependencies and Portability
Even if you use assembly language, the underlying system requires operating system dependencies, which are typically written in C, C , or Objective-C. This means that even if you had a system designed entirely in assembly, it would still depend on the underlying C or C code to manage essential functionalities like GUI, file systems, clipboard management, and more. This dependency is what ensures the system behaves uniformly across different platforms.
The Role of High-Level Languages in Modern Systems
Java, for example, is a prime example of a higher-level language that is used extensively in modern systems. When you open the Java source code, you will find numerous C or C files, .dlls, and .h headers. This interdependence is essential for the system to function correctly. Even assembly language, if used, would need to rely on simulators or tools that are ultimately written in higher-level languages.
Summary
While assembly language can offer significant performance benefits, the choice of programming language is influenced by a complex interplay of factors, including development speed, code maintainability, and portability across multiple platforms. Modern high-level programming languages like Java and C are optimized for these aspects, making them the preferred choice in most scenarios.
Conclusion
Ultimately, the decision to use higher-level programming languages or assembly should be guided by the specific requirements and constraints of the project. While assembly language might offer a slight performance edge in certain contexts, the advantages of using a higher-level language in terms of development speed and ease of maintenance often outweigh this benefit.