Re: using DCompute

2017-07-27 Thread James Dean via Digitalmars-d-learn

On Friday, 28 July 2017 at 00:23:35 UTC, Nicholas Wilson wrote:

On Thursday, 27 July 2017 at 21:33:29 UTC, James Dean wrote:
I'm interested in trying it out, says it's just for ldc. Can 
we simply compile it using ldc then import it and use dmd, 
ldc, or gdc afterwards?


The ability to write kernels is limited to LDC, though there is 
no practical reason that, once compiled, you couldn't use 
resulting generated files with GDC or DMD (as long as the 
mangling matches, which it should). This is not a priority to 
get working, since the assumption is if you're trying to use 
the GPU to boost your computing power, then you like care 
enough to use LDC, as opposed to DMD (GDC is still a bit behind 
DMD so I don't consider it) to get good optimisations in the 
first place.




Yes, but dmd is still good for development since LDC sometimes 
has problems.


Can we compile kernels in LDC and import them in to a D project 
seamlessly? Basically keep an LDC project that deals with the 
kernels while using dmd for the bulk of the program. I mean, is 
it a simple import/export type of issue?






using DCompute

2017-07-27 Thread James Dean via Digitalmars-d-learn
I'm interested in trying it out, says it's just for ldc. Can we 
simply compile it using ldc then import it and use dmd, ldc, or 
gdc afterwards?


---
a SPIRV capable LLVM (available here to build ldc to to support 
SPIRV (required for OpenCL)).
or LDC built with any LLVM 3.9.1 or greater that has the NVPTX 
backend enabled, to support CUDA.

---

Is the LDC from the download pages have these enabled?

Also, can DCompute or any GPU stuff efficiently render stuff 
because it is already on the GPU or does one sort of have to jump 
through hoops to, say, render a buffer?


e.g., suppose I want to compute a 3D mathematical function and 
visualize it's volume. Do I go in to the GPU, do the compute, 
back out to cpu, then to the graphics system(opengl/directX) or 
can I just essentially do it all from the gpu?




Randomed/encoded code

2017-07-27 Thread James Dean via Digitalmars-d-learn
I would like to encode code in such a way that each compilation 
produces "random" code as compared to what the previous 
compilation produced, but ultimately the same code is ran each 
time(same effect).


Basically we can code a function that does a job X in many 
different ways. Each way looks different in binary but does the 
same job(Same effect). I'd like a way to sort of randomly 
sample/generate the different functions that do the same job.



The easiest way to wrap your head around this is to realize that 
certain instructions and groups of instructions can be 
rearranged, producing a binary that is different but the effect 
is the same. Probably, ultimately, that is all that can be 
done(certain other tricks could possibly be added to increase the 
sampling coverage such as nop like instructions, dummy 
instructions, etc).


The main issue is how to take an actual D function and transform 
it in to a new D function, which, when ran, ultimately does the 
same thing as the original but is not the same "binary".


Encrypting is a subset of this problem as we can take any string 
and use it to encode the code then decrypt it. And this may be 
usable, but then the encryption and decryption instructions must 
somehow be randomizable, else we are back at square one. It might 
be easier though, to use the encryption method to randomize the 
original function since the encryption routine is known while the 
original function is not(as it could be any function).


I'm not looking for a mathematical solution, just something that 
works well in practice. i.e., The most skilled human reading the 
disassembly would find it very difficult to interpret what is 
going on. He might be able to figure out one encryption routine, 
say, but when he sees the "same code"(same effect) he will have 
to start from scratch to understand it because its been 
"randomized".


The best way I can see how to do this is to have a list of well 
known encoding routines that take an arbitrary function, encrypt 
it. Each routine can be "randomized" by using various techniques 
to disguise it such as those mentioned earlier. This expands the 
list of functions tremendously. If there are N functions and M 
different ways to alter each of those functions then there are 
N*M total functions that we can use to encrypt the original 
function. If we further allow function composition of these 
functions, then we can get several orders of magnitude of 
complexity with such as a few N.


The goal though, is to do this efficiently and effectively in a 
way that can be amended. It will be useful in copy protection and 
used with other techniques to make it much more effective. 
Ultimately the weak point with the encryption techniques is 
decryption the functions but by composing encryption routines 
makes it stronger.


Any ideas how to achieve this in D nicely?







Code Construction

2017-07-14 Thread James Dean via Digitalmars-d-learn
Heres a module I just started working on, completely 
incompletely, but demonstrates an ideas that might be very useful 
in D: Code Construction.


The idea is very simple: We have code strings like "class 
%%name%% { }"


and %%name%% is replaced with the name of a type T.

The idea is that we can map a type to a code string and have the 
type "fill in the blanks" rather than having to do it all in D, 
which is far more verbose and terse, we can do it using a 
different method.


Eventually the idea is that we can take any type T, map it in to 
a code string, then map that string to a new type that relates to 
T.


What I use this for is to simplify generating related members.

enum eState
{
Ready,
Starting,
Running,
Pausing,
Paused,
Unpausing,
Stopping,   
Stopped,
Finished,
}


Can be used to generate new stuff:


mixin(sCodeConstruction.MemberMap!("\t\tsMultiCallback!callbackSignature 
Callback_%%name%%;\n", eState));

Generates the following code:

sMultiCallback!callbackSignature Callback_Ready;
sMultiCallback!callbackSignature Callback_Starting;
sMultiCallback!callbackSignature Callback_Running;
sMultiCallback!callbackSignature Callback_Pausing;
sMultiCallback!callbackSignature Callback_Paused;
sMultiCallback!callbackSignature Callback_Unpausing;
sMultiCallback!callbackSignature Callback_Stopping;
sMultiCallback!callbackSignature Callback_Stopped;
sMultiCallback!callbackSignature Callback_Finished;


and if the enum changes, one does not have to regenerate the 
callbacks. (Obviously this is a simple case and D can handle this 
reasonably easily, but the more complex cases are far more 
verbose than what can be done by substitutions)


Using a substitution grammar is a lot easier IMO and D needs 
something like. Unfortunately, I won't be finishing it anytime 
soon so I thought I'd mention the idea and maybe someone else 
could tackle it.




module mCodeConstruction;
import std.meta, std.traits, std.string, std.algorithm, 
std.array, std.conv;




/*
Code construction that simplifies common tasks. 
*/

struct sCodeConstruction
{
		//[ For examples, let X in myModule.myClass.X represents the 
member `int X = 4;` and Y in myModule.myClass.Y be `bool Y(double 
q)`]

public static:
enum Tokens : string
{
		Name= "%%name%%",	// The member name (X => "X", Y => 
"Y")
		FullName			= "%%fullName%%",// The full member name (X => 
"myClass.X", Y => "myClass.Y")
		CompleteName		= "%%completeName%%",			// The complete member 
name (X => "myModule.myClass.X", Y => "myModule.myClass.Y")
		Value= "%%value%%",	// The default value of the member 
(X => 4, Y => "")
		Type= "%%type%%",	// The type of the member (X => int, 
Y => bool delegate(double))
		Module= "%%module%%",	// The module the member is in (X 
=> "myModule", Y => "myModule")
		ParentType			= "%%parentType%%",// The type of the parent 
(X => "class", Y => "class")
		MethodReturn		= "%%method/return%%",			// The return type of a 
member if it has one (X => "", Y => "bool")
		MethodParamNName	= "%%methodParam/N/Name%%",		// The Nth 
parameter's name (Y => "q")
		MethodParamNType	= "%%methodParam/N/type%%",		// The Nth 
parameter's type (Y => "double")

DoublePercent   = "%%%",
  // the %% symbol
}


/*
		A Resolver is a function takes a grammar symbol and returns the 
corresponding element for it from T.

The following list of resolvers are provided for common use:

		MemberResolver: Resolves member information: 
MemeberResolver("%%name%%", myClass.X) = "X".

*/
auto MemberResolver(string S, alias T)()
{
mixin("import "~moduleName!(T)~";");
mixin("alias val = " ~ fullyQualifiedName!(T) ~ ";");

switch(S)
{
case Tokens.Name : return to!string( 
__traits(identifier, T));

}

//pragma(msg, name);
		static if (is(typeof(T) == function) || is(typeof(*T) == 
function))

{

// Get the parameters in a (w)string array.
			enum p = split(Parameters!(member).stringof[1..$-1], 
",").map!(n => strip(n));

Tuple!(S,S)[] params;
foreach(a; aliasSeqOf!(p))
{
}
}   

return "";
}

auto StandardResolver(string S, alias