汇编编程比高级语言(如c)花费更长的时间,更难编程,这似乎是一种主流观点。因此,出于这些原因以及更好的可移植性,似乎建议或假设用高级语言编写更好。

最近我一直在用x86汇编语言写作,我开始意识到这些原因可能都不是真的,除了可移植性。也许这更多的是一个熟悉的问题,知道如何写好汇编。我还注意到在汇编中编程与在HLL中编程有很大的不同。也许一个好的、有经验的汇编程序员可以像一个有经验的C程序员用C写程序一样轻松、快速地编写程序。

也许是因为汇编编程与hll有很大的不同,因此需要不同的思维、方法和方式,这使得对不熟悉的人编写程序看起来非常尴尬,因此给汇编编程带来了不好的名声。

如果可移植性不是问题,那么C语言比NASM这样的优秀汇编器有什么优势呢?

编辑: 我只是想指出。当你用汇编语言写作时,你不必只写指令代码。您可以使用宏、过程和您自己的约定来进行各种抽象,使程序更模块化、更可维护、更易于阅读。这就是熟悉如何编写好的汇编的原因。


当前回答

作为一名大部分时间都在嵌入式编程领域工作的开发人员,我认为汇编语言还远远没有成为一种死亡/过时的语言。有某种接近金属级别的编码(例如,在驱动程序中)有时不能用高级语言准确或有效地表达。我们几乎所有的硬件接口例程都是用汇编程序编写的。

That being said, this assembly code is wrapped such that it can be called from C code and is treated like a library. We don't write the entire program in assembly for many reasons. First and foremost is portability; our code base is used on several products that use different architectures and we want to maximize the amount of code that can be shared between them. Second is developer familiarity. Simply put, schools don't teach assembly like they used to, and our developers are far more productive in C than in assembly. Also, we have a wide variety of "extras" (things like libraries, debuggers, static analysis tools, etc) available for our C code that aren't available for assembly language code. Even if we wanted to write a pure-assembly program, we would not be able to because several critical hardware libraries are only available as C libs. In one sense, it's a chicken/egg problem. People are driven away from assembly because there aren't as many libraries and development/debug tools available for it, but the libs/tools don't exist because not enough people use assembly to warrant the effort creating them.

最后,任何语言都有适用的时间和地点。人们使用他们最熟悉和最有成效的东西。在程序员的程序库中可能总会有汇编的位置,但是大多数程序员会发现他们可以用一种高级语言编写代码,这种语言在更少的时间内几乎同样高效。

其他回答

跟我们不再去外面厕所的原因一样,也跟我们不再说拉丁语和阿拉姆语的原因一样。

技术的出现使事情变得更容易,更容易获得。

编辑——为了不冒犯别人,我删除了某些词语。

合理水平的汇编能力是一项有用的技能,特别是当您从事任何类型的系统级或嵌入式编程时,这并不是因为您必须编写那么多汇编程序,而是因为有时了解盒子的实际功能非常重要。如果您对汇编程序的概念和问题没有低级的理解,这可能会非常困难。

然而,至于在汇编器中实际编写大量代码,有几个原因导致它做得不多。

There's simply no (almost) need. Except for something like the very early system initialization and perhaps a few assembler fragments hidden in C functions or macros, all very low-level code that might once have been written in assembler can be written in C or C++ with no difficulty. Code in higher-level languages (even C and C++) condenses functionality into far fewer lines, and there is considerable research showing that the number of bugs correlates with the number of lines of source code. Ie, the same problem, solved in assembler and C, will have more bugs in assembler simply because its longer. The same argument motivates the move to higher level languages such as Perl, Python, etc. Writing in assembler, you have to deal with every single aspect of the problem, from detailed memory layout, instruction selection, algorithm choices, stack management, etc. Higher level languages take all this away from you, which is why are so much denser in terms of LOC.

从本质上讲,以上所有内容都与汇编程序与C或其他语言中可用的抽象级别有关。汇编程序迫使您自己制作所有的抽象,并通过您自己的自律来维护它们,而任何中级语言,如C,特别是高级语言,都可以为您提供开箱即用的抽象,以及相对容易地创建新抽象的能力。

C是一个宏汇编器!这是最好的一个!

它可以做几乎所有汇编程序可以做的事情,它是可移植的,在大多数极少数情况下,当它不能做一些事情时,你仍然可以使用嵌入式汇编代码。这就只留下了一小部分程序,你绝对需要用汇编来编写,而且只需要汇编。

更高层次的抽象和可移植性使大多数人更值得用c语言编写系统软件。尽管你现在可能不需要可移植性,但如果你在编写某个程序上投入了大量的时间和金钱,你可能不想把自己限制在将来可以使用它的地方。

我相信有很多原因,但我能想到的两个原因是

汇编代码肯定更难读(我肯定编写它也更耗时) 当您有一个庞大的开发团队在开发一个产品时,将代码划分为逻辑块并通过接口进行保护是很有帮助的。

汇编在不同的微处理器之间是不可移植的。