4 votes
Accepted

How are processor instructions stored in RAM?

Some processors - generally, 32-bit RISC ones - make sure that all instructions fit in one location in memory. This works for them because 32 bits is enough to fit plenty of instructions, and it makes ...
user253751's user avatar
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3 votes
Accepted

Is a CPU with a hybrid Instruction Set Architecture (ISA) possible?

What you're talking about is known as asymmetric multiprocessing, where you have multiple logical cores with different ISAs. Not only is it possible, you might have one. Many consumer-grade CPUs have ...
Pseudonym's user avatar
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3 votes

How does a CPU jump to a instruction thats no longer in ram?

The program counter holds an address. Period. The CPU fetches an instruction from that address. Period. Most CPUs today have a hardware unit called an MMU (memory management unit) which sits between ...
user253751's user avatar
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3 votes

What is a procedure?

Almost every programming language has a way to specify sequences of instructions that can be reused (or used once). But programming languages don't agree on what these are called. Sometimes they are ...
user253751's user avatar
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3 votes
Accepted

What is a procedure?

A lot of this comes down to specific semantics. There are some core ideas that are switched around depending mostly on the language, I'll share the version that I'm used to and how they're different ...
Exalted Toast's user avatar
3 votes
Accepted

How can an instruction be fetched every cycle?

So, how does the CPU fetch a new instruction every cycle, if it takes more than one cycle to even fetch an instruction? It could be done by starting the next fetch before the previous one completed. ...
harold's user avatar
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2 votes
Accepted

What kind of binary compatibility is present for 2 processors sharing an Instruction Set?

Most binaries compiled for x86 will work on x86 because all x86 processors have the same binary instruction format. Instruction set extensions are quite rare and happen after several consultations ...
user123's user avatar
  • 1,102
2 votes
Accepted

How many operands does the NOP instruction have?

A 0-operand instruction is simply an instruction that takes no operand. As a result, if such an instruction changes some data either in memory or in some register, the corresponding address or ...
Steven's user avatar
  • 29.4k
1 vote

How many operands does the NOP instruction have?

To name one example, one of the NOPs in x86 (there's a bunch!) is encoded as 90. It's a special case of the family of instructions encoded as ...
harold's user avatar
  • 2,028
1 vote

What is the reason or advantage of having special purpose status flags for the result of comparisons?

You have two choices. Either you have separate compare instructions for ==, !=, <, <= etc. which all create 0 or 1, or you have one compare instruction creating flags and various branch ...
gnasher729's user avatar
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1 vote

What is a procedure?

Outside computing, a procedure is a way of doing things. It usually has specific steps in a specific order, possibly to be executed by different parties. In computing, an algorithm is a way of ...
reinierpost's user avatar
  • 5,499
1 vote

Why scopes in general do not have prologue and epilogue instructions?

At every point in time, the space on the stack must be large enough to handle all variables that are in scope. And you generally don't want to use more stack space than needed to avoid wasting space. ...
gnasher729's user avatar
  • 29.4k
1 vote
Accepted

Why scopes in general do not have prologue and epilogue instructions?

You have made an assumption about scopes in the C language which is not correct. Unlike general Algol family languages, C does not have infinitely nested scopes for every statement block. Although ...
Brian Tompsett - 汤莱恩's user avatar

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