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Email Address. All Sign in options. Enter a Email Address. Choose your interests Get the latest news, expert insights and market research, sent straight to your inbox. Newsletter Topics Select minimum 1 topic. Anonymous October 21, 0 Comments. Compilers now are smart enough that they do optimization better than somebody else. Michael S. Anuroop Jesu Posted October 25, 0 Comments. Yes, there is lot of code written in the assembly if you look at the Linux kernel code.
Regards Anuroop. Paul Pedant Posted October 26, 0 Comments. Whatever value will make the CPU do a subtraction. So a program could look like this don't try to understand it, since I made up this particular version of machine code to explain things :.
Does this suck to read? But we need it for the CPU. Well, if every machine code corresponds to a particular action, lets just make a simple "English" shorthand, and then once we understand what the program is doing, convert it into real binary machine code and give it to the CPU to run. Note that this English version has an exact mapping to machine code.
So when we write a line of this "English", we're really just writting friendlier and more understandable machine code. Well, this is assembly language. That's why it exists, and why it was originally created.
To understand why we need it now, read the above answers, but the key this to understand is this: High level languages do not have a single representation is machine code. This sounds just like our addition from above, assuming x is in register 1, y is in register 2, and z should end up in register 3. But what about this line? Try representing that line in 16 bits of binary and telling a CPU "go".
You can't. Machine code has no single operation instruction to perform an addition, subtraction, and whatever else with 4 or 5 variables at once. So it has to be converted to a sequence of machine code first. This is what you do when you "compile" or "interpret" a high level language. Well, we have programs to do that, so why do we need assembly now?
Well say your program is running more slowly than you expect, and you want to know why. Looking at the machine language "output" of this line, it might look like:. Just to get that one line of Python done. So you really want to debug that?!?!?! Rather, you ask your compiler to kindly give you the output in the form you can actually understand easily, which is the assembly language version corresponding exactly to that machine code. Then you can figure out if your compiler is doing something dumb and try to fix it.
For practical purposes though, we really have stuck to binary. Each assembly language was created for just one processor or family of processors as the instructions mapped directly to opcodes run by the processor.
If you need to program device drivers or write compilers then understanding how a processor works is invaluable, if not required. The best way to understand this is to write some code in assembly. If you take a look at how a compiler writes code it is common to see options for calling conventions which without knowing assembly probably can't be understood. If you have to resolve a bug and the only input you have is a core dump , then you definitely need to know assembly to understand the output which is assembly code and if lucky augmented with higher level statements of a high level language.
Let me add one less practical aspect. This is probably not a historic reason but a reason for you, today. Assembly compared to high-level languages is naked. It does not hide anything that is done in software , and it is simple in the sense that it has a relatively small, fixed set of operations. This can be helpful for exact algorithm analysis. Semantics and control flow are so simple that counting all operations or the expected number can be done by annotating the control flow graph with transition counts probabilities.
Knuth does this in his TAoCP books to great effect, demonstrating some of the most rigorous algorithm analyses there are. When do we need assembly language? Why assembly language is still needed if we have high level languages offering sophisticated tools? Why Study Assembly language? This whilst true completely misses the point. As far as translation goes assembly language and the numeric binary, hex whatever are one and the same thing.
Grok it or drop it If you grok assembly you know how an actual computer works. If you grok assembly you well have a nearly complete picture of how the CPU connected to your keyboard works. You need to use this knowledge like a brain surgeon uses his scalpel. Don't need no stinking abstractions Unless you grok assembly and thus the CPU on the operating table you will never be free of the clutches of the abstractions of the RAM machine or god forbid the Turing machine the horror.
L33t Hax0r 5k1llz Assembly also helps to you understand how the thax0r manages to defeat the protection schemes. Q: why does ASLR not work? The 0. If you want to know the machine, you must understand it and that means speaking the language of the machine. Assembly Language mainly consists of mnemonic processor instructions or data and other statements or instructions.
Assembly Language helps in fine-tuning the program. Assembly language helps programmers to write human-readable code that is almost similar to machine language. Machine language is difficult to understand and read as it is just a series of numbers. Assembly language helps in providing full control of what tasks a computer is performing.
The learning of assembly language is still important for programmers. It helps in taking complete control over the system and its resources. By learning assembly language, the programmer can write the code to access registers and retrieve the memory address of pointers and values.
It mainly helps in speed optimization that increases efficiency and performance. Assembly language learning helps in understanding the processor and memory functions. If the programmer is writing any program that needs to be a compiler, that means the programmer should have a complete understanding of the processor.
Assembly language helps in understanding the work of processors and memory. It is cryptic and symbolic language. Assembly Language helps in contacting the hardware directly. This language is mainly based on computer architecture, and it recognizes a certain type of processor and its different for different CPUs.
Assembly language refers to transparency compared to other high-level languages.
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