Flexible Instruction Set Encoding.

Look up the transmeta code-morphing system. It handled the 16/32-bit problem by hoisting the mode check out of each instruction.

Now see my first post why this is slow.

Bye, Skybuck.

Apperently my first post wasn't clear enough for ya.

The idea is to:

Have the CPU implement the IF statement in it's logic circuits so that the IF overhead is prevented.

And the boolean is replaced by some integer for more mode support.

This was the program will use fast 32 bit instructions when possible or use slower 64 bit emulated instructions.

The cpu must provide 64 bit emulated instructions as well.

Future processors could then replace those under water with true 64 bit operations possibly, and ofcourse 128 bit in the future etc.

Well it's too late for that now I think, we stuck with current stuff, or maybe not who knows ?! ;)

Bye, Skybuck.

You completely missed the compatibility requirement.

The application must have 64 bit support even on 32 bit systems. Think NTFS.

Simply recompiling int to int64 won't work !

Bye, Skybuck.

Hi, thanks very much for your suggestion.

It might be possible to create three libraries:

1. A 32 bit version.

1. A true 64 bit version.

2. A emulated 64 bit version.

Problem 1:

Passing parameters to the routines.

The different versions have different parameters.

Problem 2:

Calling the routines

^^^ Different parameters requires different calls ^^^

Lastly:

This still requires an easy method to generate the 3 libraries with just one source code:

This could be as simple as redeclaring a type:

Type // TgenericInteger = int32; TgenericInteger = int64;

And then rebuilding the library.

Now a solution has to be found for problem 1 and problem 2.

Without adding to much overhead.

Bye, Skybuck.

You starting to grasp the concept.

It's not so much about telling routines what to do.

It's telling the cpu what to do.

It could be on a routine to routine basis.

Use the BitMode variable in front of the routine to tell the cpu all instructions in the routine should be interpreted using the specified bitmode.

Bye, Skybuck.

Actually there is a third problem kinda:

The program loads a certain library at runtime:

It could be a 32 bit or emulated 64 bit.

This creates a debugging problem.

Suppose the code was lastly compiled in 64 bit.

And the program chooses 32 bit.

(Or vice versa)

Then the source code does not match the loaded library.

Bye, Skybuck.

Yes that's another benefit.

Shorter instruction encodings me thinks ;)

Bye, Skybuck.

Show me an application, source code, asm, anything which:

1. Runs single 32 bit instructions on 32 bit operating system.

1. Runs single 64 bit instructions on 64 bit operating system.

2. Runs multiple 32 bit instructions for 64 bit emulation on 32 bit operating system.

1. Has the same source code for all three cases.

2. Needs to compile once. (I'll throw in some slack three times).

1. Switches to the optimal/necessary instructions mentioned above at runtime.

Bye, Skybuck.

Any decent C compiler has a 64-bit integer type regardless of what CPU it's targeted at; it's a requirement of ISO C99. If targeted at a 32-bit (or 16- or 8-bit) CPU, the compiler emulates 64-bit operations. This is not novel; C89 compilers targeting 8- and 16-bit CPUs provided the same emulation for

I'm not familiar with many other languages, but I believe the same is true. If you use a 64-bit integer type, the compiler or interpreter does whatever's needed to provide the illusion of a machine that natively supports such.

The cost of determining whether 64-bit emulation is needed on a 32-bit system and falling back to 32-bit operations when it's not is higher than the cost of just using it all the time.

If you're on a true 64-bit system, run the binary that was recompiled for that architecture. The source will be identical if it's properly written (well, except for ASM; I'm talking HLLs).

That logic is already there; the same opcodes are used for 16-, 32-, and

The problem, which you keep refusing to acknowledge, is that you can't load or store data of indeterminate size because the compiler (or assembly coder) needs to know how much space to reserve for objects at compile time. And, of course, loads are by far the biggest consumer of CPU time in a typical application -- some spend up to 80% of their time waiting on memory. Worrying about a few extra _nano_seconds to execute emulated 64-bit operations on a 32-bit machine is pointless when that same machine just waited tens of _micro_seconds for the data to show up. Any unpredictable branches, like doing run-time checks on data to see whether or not to use emulation, will stall the pipeline and cost up to tens of microseconds again to save a few nanoseconds of execution time.

If the CPU provides 64-bit operations, it's not emulation -- it's a 64-bit CPU. It may take longer to process 64-bit ops than 32-bit ops, but reality shows that's not the case in shipping CPUs. Either the CPU doesn't do

It's obvious you don't even understand the "current stuff". Go read a book or ten, get some real world experience, and quit wasting others' time with your inane ideas.

I refuse and reject this argument of yours !

Object Oriented languages have objects which are created at runtime !

The data/memory for the objects are reserved at runtime !

During the constructor/create calls, enough memory can be reserved.

If the programmer can somehow tell the object what it needs the object can reserve the necessary ammount of memory !

The only thing left to do is tell the cpu how much memory it's supposed to operate on !

The real problem is with the cpu and the instruction encoding it uses.

Each instruction must specify register(s) to operate on.

This implicitly means the instruction encoding is fixed bit, and can not be changed.

Some people refuse this explanation and say that this is not true...

They say 16/32 had some kind of bit mode flags.

Some people say: 64 bit has bit mode flags.

I told them:

Show me an example !

Their reponse:

NOTHING.

I will believe it, when I SEE IT !

(alt.lang.asm included, since they might know something)

Bye, Skybuck.

Most programming languages have that concept, whether they're designed to make OO easy or not. Dynamic memory allocation has been old news for, what,

If you're using a constructor, you've already lost the performance war vs. a compiler's (and CPU's) built-in types, even ones that have to be emulated.

No, there's a lot of other things. For instance, your "flexible" objects that you proposed in your C++ implementation actually result in multiple static code paths that you select between using incredibly inefficient (for this purpose) virtual method calls and operator overloading. Simply emulating 64-bit operations on CPUs that don't have such is going to be faster.

Irrelevant. The actual math operations have the same opcodes for 16-, 32-, and 64-bit values, and they do the exact same things to all three types of data.

Sort of. The mode flags only really control load/store operations. But they're there.

Actually, people have given you exact references, but you know so little about the x86 and AMD64 architectures that you didn't understand or even recognize them.

Oh gee... lemme crank out some POC here... oh wait... that's right... it is not our job to spoon-feed you source code, it is your job to RTFM and hopefully learn from them.

yes.

for example, there is also a non-standard extension feature (I think maybe in gcc in 32-bit land as well, but not checked) known as '__int128', or a full on 128 bit integer type.

my compiler has a placeholder for this, but as of yet does not implement this type (can declare variables, but can't assign them or do arithmetic on them...).

Actually, only 2 and 3 are relevant here, because you first have to figure out if you need 32-bit or 64-bit data. If you don't know that, then your problem is either not well enough specified for you to start coding, or is so vague and general that you are better off using abstract types rather than fixed sizes (and probably better using a language such as Python, which has direct support for arbitrarily long integers, and can be combined with psyco to generate reasonably good machine code on the fly).

This solves your problems, since you are only ever passing 64-bit data.

Generating the different dlls (or other types of libraries or code) is easy - it's just a compiler flag to target x86 or amd64 code generation.

You should read it yourself because you clearly don't understand it.

Bye, Skybuck.

Oh wait that was steven who wrote rex prefix is for extra registers.

The rex prefix is also necessary to specify the operand size is 64 bit !

The manual says so ;)

Bye, Skybuck.