[AHK v2 64-bit] Compile C to memory using TCC

[oif2003]

Hi,

Here's a script for writing C functions inside AHK scripts. It uses TCC's libtcc.dll to compile C code to memory and returns a function pointer without saving temporary files to disk. Unlike MCode, code is compiled when an object of class tcc is instantiated. Code can be added either as a string literal or as a comment block. Requires TCC and AHK v2 64 bit.

https://bellard.org/tcc/
https://download.savannah.gnu.org/relea ... 64-bin.zip

Usage:

Code: Select all

;define a C function string
string1 := new tcc('
	(
		char* hello() {
			return "hello world";
		}
	)')
msgbox(DllCall(string1["hello"], "AStr"))

Code: Select all

;explicitly include User32.dll so MessageBox will work
comment2 := new tcc(parseC("Block 2"),,, "C:\Windows\System32\User32.dll") 
/*_C Block 2
	#include <stdio.h>
	#include <windows.h>
	
	int hello(char name[]) {
		char buf[256];
		snprintf(buf, sizeof buf, "Hello %s!", name);
		MessageBox(0, buf, "Greeting", 0);
	}
*/
DllCall(comment2["hello"], "AStr", A_UserName)

Full script:

Spoiler

Code: Select all

/*
	AHK v2 (64-bit) LIBTCC by oif2003 (16 Dec 2018)
	This script allows the use of C code within AHK. C code is compiled and loaded into 
	memory using libtcc.dll.  Function pointers are used for DllCall.
	Requires TCC: https://download.savannah.gnu.org/releases/tinycc/tcc-0.9.27-win64-bin.zip
	Place script in TCC folder or locate it when prompted. (or set tcc.__defPath)
	For more information on TCC: https://bellard.org/tcc/
*/
#singleinstance force

;----------------------------
;define C functions with strings
	string1 := new tcc('
		(
			#include <wchar.h>
			
			wchar_t* hello() {
				return L"hello world";
			}
		)'
	)
	MsgBox(DllCall(string1["hello"], 'Str'))

	haystack := "The quick brown fox jumps over the lazy dog."	,tcc.__StrPutVar(haystack, _haystack)
	needles  := "high"											,tcc.__StrPutVar(needles, _needles)
	string2 := new tcc('
		(
			#include <string.h>
			
			int match(char *haystack, char *needles) {
				int r = strpbrk(haystack, needles) - haystack + 1;
				return r > 0 ? r : 0;
			}
		)'
	)
	pos := DllCall(string2["match"], 'Str', _haystack, 'Str', _needles)
	MsgBox('Found "' SubStr(haystack, pos, 1) '" at position ' pos ' in haystack: "' haystack '" using needles: "' needles '"')

;---------------------------
;define C functions in comment blocks
	comment1 := new tcc(parseC("Block 1")) 
	;block tags ("Block 1" here) must not be followed by anything other than a new line
	/*_C Block 1
		#include <math.h>
		
		int inc() {
			static int i = 0;
			return ++i;
		}
		
		double Csqrt(double x) {
			return sqrt(x);
		}
	*/
	MsgBox("Csqrt(" format("{:.3g}", x := 3.14**2) ")"
			. " ~ " format("{:.3g}", DllCall(comment1["Csqrt"], 'Double', x, 'Double'))
	)
	
	;save function pointer to variable for speed
	f := comment1["inc"], t := A_TickCount
		loop 1000000
			x := DllCall(f)
	MsgBox("x = " x " (Time elapsed: " A_TickCount - t " ms)" )

	;explicitly include User32.dll so MessageBox will work
	comment2 := new tcc(parseC("Block 2"),,, "C:\Windows\System32\User32.dll") 
	/*_C Block 2
		#include <stdio.h>
		#include <windows.h>
		
		int hello(char name[]) {
			char buf[256];
			snprintf(buf, sizeof buf, "Hello %s!", name);
			MessageBox(0, buf, "Greeting", 0);
		}
	*/
	DllCall(comment2["hello"], 'AStr', A_UserName)

;===============================================================================================================
parseC(tag := "", path:="") {	;reads C code between labels
	static script, lastpos := 1
	return (
		path := path ? path : A_ScriptFullPath
		,startLabel := "/*_" "C " tag "`r" 			
		,endLabel   := "*/"
		,script || script := fileRead(A_ScriptFullPath) 
		,cStart  := InStr(script, startLabel, ,lastpos) + StrLen(startLabel)
		,lastpos++ := cEnd := InStr(script, endLabel, , cStart + 1)
		,SubStr(script, cStart, cEnd - cStart)
	)
}

class tcc {	
	static 	 __defPath := A_ScriptDir
			,__instanceCount := 0
			,__hModule := 0
			
	__New(cStr, tccPath := "", opts := "", addfiles*) {	;opts: literal option string, addfiles := variadic array of paths
		static	 _path := ""
				,tcc_add_file := 0x1B2B4
				,tcc_compile_string := 0x1CF83
				,tcc_free := 0x2FC4
				,tcc_new := 0xF703
				,tcc_relocate := 0x1C71C
				,tcc_set_options := 0xD8E5
				,tcc_set_output_type := 0xF5A9
				,TCC_OUTPUT_MEMORY := 1
				,TCC_RELOCATE_AUTO := 1

		tccPath := _path ? _path : (tccPath ? tccPath : tcc.__defPath)
		while !FileExist(tccPath "\libtcc.dll")
			_path := (tccPath := DirSelect(, , "Locate TCC folder.  Close to exit.")) ? tccPath : ExitApp()
		 
		(tcc.__hModule) || tcc.__hModule := DllCall("LoadLibrary", 'Str', tccPath "\libtcc.dll", 'Ptr') 
		,libtcc := tcc.__hModule
		,context := DllCall(libtcc + tcc_new, 'Ptr') 

		,(opts) && (this.__StrPutVar(opts, options), DllCall(libtcc + tcc_set_options, 'Ptr', context, 'Str', options))
		for _, v in addfiles
			this.__StrPutVar(v, filename), DllCall(libtcc + tcc_add_file, 'Ptr', context, 'Str', filename)
		
		 DllCall(libtcc + tcc_set_output_type, 'Ptr', context, 'UInt', TCC_OUTPUT_MEMORY, 'Int')
		,this.__StrPutVar(cStr, _cStr), DllCall(libtcc + tcc_compile_string, 'Ptr', context, 'Str', _cStr, 'Int')
		,DllCall(libtcc + tcc_relocate, 'Ptr', context, 'Ptr', TCC_RELOCATE_AUTO, 'Int')
		
		,this.__context := context
		,this.__symbols := {}
		,tcc.__instanceCount++
	}
	
	__Get(f) {
		static tcc_get_symbol := 0x80E2
		return (
			this.__symbols[f] ? (
				 this.__symbols[f]					
			):(
				 this.__StrPutVar(f, _f)
				,this.__symbols[f] := DllCall(tcc.__hModule + tcc_get_symbol, 'Ptr', this.__context, 'Str', _f, 'Ptr')
			)
		)
	}
	
	__Delete() {
		static tcc_delete := 0xD543
		 DllCall(tcc.__hModule + tcc_delete, 'Ptr', this.__context)
		,(--tcc.__instanceCount == 0) && DllCall("FreeLibrary", 'Ptr', tcc.__hModule)
	}
	
	__StrPutVar(ByRef str, ByRef var) {    
		return (VarSetCapacity(var, StrPut(str, "UTF-8")), StrPut(str, &var, "UTF-8"))
	}
}

Edit: Minor fixes

[nnnik]

Nice - I can already see this replacing MCode.

[Helgef]

Great job, works great .

Cheers.

[nnnik]

How does TCC compare to compiled code by VSC++ or gcc performance wise?

[Helgef]

As far as I remember TCC does almost no optimisations, unlike gcc which has great optimisation capabilities. However, this makes TCC fast, so in that regard it performs superior to both gcc and VS.

Cheers.

[nnnik]

As far as I can tell the compilation time is irrelevant when compared to gcc and VS.
gcc and VS are roughly similar with gcc being slightly ahead in most cases.

No optimization is kind of bad - so I guess MCode still has its uses.

[Helgef]

Yes ofc, compilation time doesn't matter once compiled .

Cheers.

[oif2003]

Thanks! Indeed, this was not intended to be a replacement for MCode, instead it's more like a scripting solution in C.

At the moment I see these potential uses:
1) for testing out C snippets as potential candidates for MCode/Dll,
2) to offer maximum transparency (as no compiled code is provided),
3) for JIT solutions that require C code to be generated at runtime

For computationally intensive tasks where portability is not required, Julia offers a viable alternative. It is fast enough to be used as a scripting language for some tasks, and it's exceptionally good at handling math. Here's a very primitive example using Julia's libjulia.dll to evaluate a string from AHK v2:
(Requires installation of Julia Language: https://julialang.org/downloads/)

Spoiler

Code: Select all

/*	
	A very primitive example of embedding Julia in AHK v2 64-bit
	by passing a string to be evaluated and getting the return value as a string
	Returning "Double" also works, and one can always execute a Julia file (.jl)
	with include("C:\\Directory\\JuliaFile.jl")
	
	Calling Julia functions directly is also possible, but requires "boxing" (not shown here)
	Reference:
		https://docs.julialang.org/en/v1/manual/embedding/#High-Level-Embedding-1
*/
#singleinstance force

;Set this to julia\bin
juliaPath := "C:\Users\" A_UserName "\AppData\Local\Julia-1.0.3\bin"	;point to  \Julia-x.x.x\bin

;Julia code string to be evaluated
s := '
(
	# Function declaration
	function test(n)
		s = ""
		for i=1:n
			s *= string(sqrt(i)) * "\n"
		end
		s
	end
	
	# Run function
	test(20)
)'

;initialize Julia
_WorkingDir := A_WorkingDir
A_WorkingDir := juliaPath
libjulia := DllCall("LoadLibrary", "Str", A_WorkingDir "\libjulia.dll", "Ptr")
DllCall("libjulia.dll\jl_init__threading", "Str", A_WorkingDir)

strAdd := (StrPutVar(s, _s, "UTF-8"), DllCall("libjulia.dll\jl_eval_string", "Str", _s))
retStr := StrGet(strAdd + A_PtrSize, NumGet(strAdd, "Int64"), "UTF-8")	;first 8 bytes is length of string
MsgBox(retStr)

;cleanup and signal Julia we are about to exit
DllCall("libjulia.dll\jl_atexit_hook", "Int", 0)
DllCall("FreeLibrary", "Ptr", libjulia)
A_WorkingDir := _WorkingDir


StrPutVar(ByRef string, ByRef var, encoding := "cp0") {    
	return (
		 VarSetCapacity(var, StrPut(string, encoding) * ((encoding="utf-16"||encoding="cp1200") ? 2 : 1))
		,StrPut(string, &var, encoding)
	)
}

Edit: Fixed typo
Edit2: Fixed code example

[CyL0N]

Dope stuff, a good enough reason to finally get on with v2. I've been putting it off for too long. Thanks dude.