On a 64bit machine, we recognize that an resolve is 8 bytes. However, ns am not completely clear how countless bytes of information is in one address.Does every byte in virtual memory have actually an address? Or go every 64 bits in memory have actually an address?Or walk it depend on the architecture? If it counts on the architecture, then just how should I find out?


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Or go it depend on the architecture?

Yes. It counts on the architecture:

For most CPUs one attend to represents 8 bits.

Each byte in the memory has actually an individual address.

The TMS320 DSP is an instance for a CPU wherein one address represents 16 bits.

This way that each 16-bit word (uint16) in the memory has an separation, personal, instance address.

There are also computers (many of castle historic) whereby each deal with represents 12, 13, 14, 16, 24 or 36 bits (and maybe also more) ...

(Unfortunately, ns don"t know an example for a CPU utilizing 64-bit addresses not using 8 bits per address but I"m fairly sure such CPUs additionally exist.)

Then there are memory species where not all addresses exist. This might look the following way:

Addresses which space divisible by 4 represent 32 bits the information; various other addresses can not be provided - which means that these addresses stand for no information in ~ all.

So the "average" end the addresses is 8 bits yet there is no deal with that represents 8 bits.

Typically you watch such a behavior in a computer system where 2 different species of memory room installed and one form allows both 8- and also 32-bit access while the other form only enables 32-bit access.

And this is frequently the case for the memory of peripheral devices - for instance the storage of the Ethernet controller in part microcontrollers.

Is much as i remember correctly, I have actually seen a PCI SCSI controller for computers that also showed this behavior. Install that SCSI controller right into your 64-bit computer and your computer system contains some variety of addresses wherein 25% of every addresses represent 32 bits the data and also 75% of every addresses don"t represent any type of data at all.

I"ve likewise seen CPUs draft by college student of colleges where the "commercial original" enables 8- and 32-bit accessibility to the memory yet the student"s replica enables only 32-bit access. In this case the entirety address selection shows this behavior.

By the way:

On a 64bit machine, we know that an attend to is 8 bytes.

Even this is not necessarily true:

As far as i know, one x86-64 CPU uses only 48-bit addresses. Thus it would be possible for a compiler manufacturer to store each resolve in only 6 bytes the memory.

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And of course CPU cores for installed devices could be design to usage a subset of the x86-64 instruction collection but it is registered that typically hold an deal with (such as rsp) are just 48 bits wide.