Hi
I have problem with XMM register. I can't change value inside them even by using MOSD or MOVLDP
I have code in C and in ASM which should do exactly the same (school project).
Could you help mi with it?
http://pastebin.com/q4Z9UzTD
http://pastebin.com/vHVp0RwE
Hi Orzel,
1. your code assembles only if the last line is END aproxASM
2. then, it starts as follows:CPU Disasm
Address Hex dump Command Comments
<ModuleEntryPoi Ú$ 55 push ebp
00401001 ³. 8BEC mov ebp, esp
00401003 ³. BB 00000000 mov ebx, 0
00401008 ³. 660F1265 28 movlpd xmm4, [ebp+28]
0040100D ³. 660F1245 08 movlpd xmm0, [ebp+8]
00401012 ³. 660F124D 10 movlpd xmm1, [ebp+10]
... and all instructions work as expected. My advice: install Olly (http://www.ollydbg.de/version2.html) and debug your executable.
Welcome to the Forum :icon14:
thanks for answer
I'm using MS VS 2015 for dubbuging (Windows forms C# app with C++ & ASM .dll's)
When I add aproxASM at the end there is no changes, but when I replace my code with yours (don't know if I should actually) Ive got some errors
screenshots: https://1drv.ms/f/s!AhFXsdGfJyB21F2tZSEVSKwjDf_n
by the way: you mean
MOV eax,ebx
ret
aproxASM endp
END aproxASM
or just
MOV eax,ebx
END aproxASM
What I showed you is the disassembly, not the source. I have used your source with one single change: the last line, which is END in your code, becomes END aproxASM
Thus, the assembler (MASM = ML.exe) knows that aproxASM is the entry point. I do not use Visual S. for assembly, it's an overkill, so I don't know what VS actually does under the hood. Try \masm32\qEditor.exe, it's a better tool.
When I've tried to assembly my code in QEditor I get "syntax error : xmm"
When I open .dll in Ollydbg the code is completly different... https://1drv.ms/i/s!AhFXsdGfJyB21GAiSPipxuAKmU1o
Mateusz,
You get the "syntax error : xmm" because Masm32 ships with a very old version of MASM. RichMasm (http://masm32.com/board/index.php?topic=5314.0) would detect this and install automatically a new one when you hit F6, but with qEditor you will have to do it manually:
- download HJWasm32 (http://www.terraspace.co.uk/hjwasm218_x86.zip)
- extract HJWasm32.exe to \Masm32\bin
- rename \Masm32\bin\ml.exe to mlv614.exe
- rename \Masm32\bin\HJWasm32.exe to ml.exe
- retry console assembly and link in qEditor
Btw you don't need screenshots to show disassemblies. Just select the lines in Olly that are interesting in Olly and hit CtrlC; then paste them here inside code tags (the # icon).
Btw in your screenshot, you show the point after LoadLibrary. The interesting part is when you call the address received by GetProcAddress.
tested with ml.exe 10
DllEntry proc
MOV EAX, 1
RET
DllEntry endp
...
...
END DllEntryor_DllMainCRTStartup proc
MOV EAX, 1
RET
_DllMainCRTStartup endp
...
...
END _DllMainCRTStartupand use def-file for dlls.
Just get a later version of ML.EXE.
debuging is ok now and it compiles to .exe but after "create new .dll" in qEditor a pasting my code (by replacing all) I get sth like that:
ASM.asm: 50 lines, 2 passes, 69 ms, 0 warnings, 0 errors
Microsoft (R) Incremental Linker Version 5.12.8078
Copyright (C) Microsoft Corp 1992-1998. All rights reserved.
ASM.def : error LNK2001: unresolved external symbol aproxASM
ASM.lib : fatal error LNK1120: 1 unresolved externals
LINK : fatal error LNK1141: failure during build of exports file
Could Not Find C:\Users\Mateusz\Documents\Visual Studio 2015\Projects\Generator fraktali 2D\ASM\masmdll\ASM.exp
Volume in drive C is OS
Volume Serial Number is 8482-C98C
Directory of C:\Users\Mateusz\Documents\Visual Studio 2015\Projects\Generator fraktali 2D\ASM\masmdll
21.01.2017 10:34 1 662 ASM.asm
21.01.2017 10:36 31 ASM.def
2 File(s) 1 693 bytes
0 Dir(s) 35 056 488 448 bytes free
ASM.def is:
LIBRARY ASM
EXPORTS aproxASM
LIBRARY ASM
EXPORTS aproxASM=_aproxASM@40
Creating library ASM.lib and object ASM.exp
ASM.exp : error LNK2001: unresolved external symbol _aproxASM@40
ASM.dll : fatal error LNK1120: 1 unresolved externals
Your ASM.def file is OK. I would choose another file name, though ;-)
The normal structure of a DLL source is like this:
.code
LibMain proc instance:DWORD, reason:DWORD, unused:DWORD
mov eax, 1
ret
LibMain endp
aproxASM proc p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
MOV ebx,0
...
ret
aproxASM endp
end LibMain
its ok know, I have some errors (exception at the exit of procedure) but I hope (or not XD) it's logic issue (I don't know yet :/ )
last thing to make sure
1) to return integer value i must put it into EAX? Is this enought or shall I do sth more with it?
2)to load library from C# app I need
[DllImport("ASM.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
static extern int aproxASM(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
or just
[DllImport("ASM.dll")]
static extern int aproxASM(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
A small test:
using System;
using System.Runtime.InteropServices;
// c:\Windows\Microsoft.NET\Framework\v2.0.50727\csc.exe aproxTestCc.cs /platform:x86
class aproxTestCs
{
[DllImport("aproxC.dll")]
static extern int aproxC(double p_real, double p_imaginary, double c_real, double c_imaginary);
[DllImport("aproxASM.dll")]
static extern int aproxASM(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
static void Main()
{
double p_real = -1.5;
double p_imaginary = -1.5;
double c_real = 0.65;
double c_imaginary = -0.03;
double four = 4.0;
int ac = aproxC(p_real, p_imaginary, c_real, c_imaginary);
Console.WriteLine("ac={0}", ac);
int aa = aproxASM(p_real, p_imaginary, c_real, c_imaginary, four);
Console.WriteLine("aa={0}", aa);
}
}C version works, but ASM version crash.
But this outputs
ac=1
aa=360#include <stdio.h>
int __stdcall aproxC(double p_real, double p_imaginary, double c_real, double c_imaginary);
#pragma comment(lib, "aproxC.lib")
int __stdcall aproxASM(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
#pragma comment(lib, "aproxASM.lib")
int __cdecl main(void)
{
double p_real = -1.5;
double p_imaginary = -1.5;
double c_real = 0.65;
double c_imaginary = -0.03;
double four = 4.0;
int ac = aproxC(p_real, p_imaginary, c_real, c_imaginary);
printf("ac=%d\n", ac);
int aa = aproxASM(p_real, p_imaginary, c_real, c_imaginary, four);
printf("aa=%d\n", aa);
return 0;
}BTW ebx is reserved register, use ecx instead or push/pop ebx
I changed to ECX, create project with your code and add .lib files by properties -> linker -> Additional Library Directories
and I got:
LNK2028 unresolved token (0A00003C) "int __stdcall aproxC(double,double,double,double)" (?aproxC@@$$FYGHNNNN@Z) referenced in function "int __cdecl main(void)" (?main@@$$HYAHXZ) test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
LNK2028 unresolved token (0A000045) "int __stdcall aproxASM(double,double,double,double,double)" (?aproxASM@@$$FYGHNNNNN@Z) referenced in function "int __cdecl main(void)" (?main@@$$HYAHXZ) test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
LNK2019 unresolved external symbol "int __stdcall aproxC(double,double,double,double)" (?aproxC@@$$FYGHNNNN@Z) referenced in function "int __cdecl main(void)" (?main@@$$HYAHXZ) test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
LNK2019 unresolved external symbol "int __stdcall aproxASM(double,double,double,double,double)" (?aproxASM@@$$FYGHNNNNN@Z) referenced in function "int __cdecl main(void)" (?main@@$$HYAHXZ) test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
LNK1120 4 unresolved externals test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\Debug\test 2.exe 1
edit: sory for such trivial (I think) things but it's my first touch to DLLs and Assembler (semester must be passed XD but its quite interesting)
My second code example is C code, not C++. Compile it as C source (*.c).
so again i've got
Error LNK2019 unresolved external symbol _aproxC@32 referenced in function _main test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
Error LNK2019 unresolved external symbol _aproxASM@40 referenced in function _main test 2 C:\Users\Mateusz\documents\visual studio 2015\Projects\test 2\test 2\Source.obj 1
first time it was caused by lack of libMain part but now I have it in ASM (but in C++ dll is error too)
Try building it without a def file but with aproxASM proc syscall export p_real: REAL8, ...
Orzel94,
Just make sure you write the correct prototypes for your C code calling either object modules written in assembler OR a DLL written in assembler. 32 bit MASM supports both STDCALL and C calling conventions, make sure you get this right and look up your compiler reference for "extern c" for the prototypes. In 64 bit the calling convention is FASTCALL and you have to get this right.
I am confused. I thought C returns to ST(0) for 32-bit floaty things.
I am a bit confused :(
ml.exe -FeaproxASM.dll aproxASM.asm -link -dll -export:aproxASM=_aproxASM@40
cl.exe -Gz -GS- -MD -FeaproxC.dll aproxC.c -link -dll -export:aproxC=_aproxC@32
cl.exe -GS- -MD aprox_test.c
aprox_test.obj : error LNK2019: unresolved external symbol _aproxC@32 referenced in function _main
aprox_test.obj : error LNK2019: unresolved external symbol _aproxASM@40 referenced in function _main
aprox_test.exe : fatal error LNK1120: 2 unresolved externals
Even after reading these:
EXPORTS
https://msdn.microsoft.com/en-us/library/aa278935(v=vs.60).aspx
-export
https://msdn.microsoft.com/en-us/library/aa235424(v=vs.60).aspx
polink.exe works as documented.
EDIT:
EXPORTS
https://msdn.microsoft.com/en-us/library/hyx1zcd3(v=vs.140).aspx
This syntax should be still validentryname[=internalname] [@ordinal [NONAME]] [[PRIVATE] | [DATA]]
EDIT:
With polib.exe or def2lib.exe we can have correct libs.LIBRARY aproxC.dll
EXPORTS
;aproxC=_aproxC@32
"_aproxC@32"LIBRARY aproxASM.dll
EXPORTS
;aproxASM=_aproxASM@40
"_aproxASM@40"
Quote from: coder on January 22, 2017, 03:56:43 PM
I am confused. I thought C returns to ST(0) for 32-bit floaty things.
That's correct. In assembly, you must do it by hand. Here are two options:
push eax ; return int(eax) in ST(0)
fild dword ptr [esp]
pop eax
ret
sub esp, 8 ; create a REAL8 slot
movlps qword ptr [esp], xmm0 ; move the value to be returned from xmm0 to the stack
fld REAL8 ptr [esp]
add esp, 8
retAs to building Mateusz' dll code, see reply #17. It works.
I have now completely mess in mind...
Without .def file i can only compile it to .exe file not .dll
even when I compile asm code which do simply nothing but returnig integer value
;-------------------------------------------------------------------------
.686
.MMX
.XMM
.MODEL FLAT, STDCALL
OPTION CASEMAP:NONE
.DATA
circle DD 360
.CODE
LibMain proc instance:DWORD, reason:DWORD, unused:DWORD
mov eax, 1
ret
LibMain endp
aproxASM proc p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
MOV eax,12
ret
aproxASM endp
end LibMain
or like jj2007 mentioned
;-------------------------------------------------------------------------
.686
.MMX
.XMM
.MODEL FLAT, STDCALL
OPTION CASEMAP:NONE
.DATA
circle DD 360
.CODE
LibMain proc instance:DWORD, reason:DWORD, unused:DWORD
mov eax, 1
ret
LibMain endp
aproxASM proc p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
MOV eax,12
push eax ; return int(eax) in ST(0)
fild dword ptr [esp]
pop eax
ret
aproxASM endp
end LibMain
I've got stack balance error
You function return int.
jj2007 comment was for float, so not for your code, if that return int.
BTW
use eax in your code as it is free register, so return value is already in right place.
That syscall tip works to decoration issue, but read this:
http://masm32.com/board/index.php?topic=3640.msg38361#msg38361
Otherwise you need some export manipulation for undecorated name.
It seems I got a solution (no def file needed):
aproxASM proc c export p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
...
ret
Attached testbed needs MasmBasic (http://masm32.com/board/index.php?topic=94.0) to build, but you can test the DLL with your C compiler as well.
@OP: It would help if you provided a usage example, i.e. five float arguments, and the expected result.
CheckMateusz.exe loads the DLL and executes aproxASM with 5 dummy args, it returns 123456789 and checks if the stack is balanced.
In case you want to test the build:
- create an empty TmpDllEx.def in the source folder, and write-protect it (sorry, this is a hack, I know)
- open Mateusz.asc in RichMasm (http://masm32.com/board/index.php?topic=5314.0)
- hit F6 to a) build the DLL and b) run CheckMateusz.exe to test it
It works also with stdcall, see second attachment.
test program in C for dll#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <stdio.h>
//int aproxASM(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
typedef int (APROXASM)(double p_real, double p_imaginary, double c_real, double c_imaginary, double four);
typedef APROXASM*PAPROXASM;
int __cdecl main(void)
{
double p_real = -1.5;
double p_imaginary = -1.5;
double c_real = 0.65;
double c_imaginary = -0.03;
double four = 4.0;
HANDLE hLib;
static PAPROXASM aproxASM;
hLib = LoadLibrary("Mateusz.dll");
aproxASM = (PAPROXASM)GetProcAddress(hLib, "aproxASM");
int aa = aproxASM(p_real, p_imaginary, c_real, c_imaginary, four);
printf("aa=%d\n", aa);
return 0;
}
YES!
it's working! (jj2007 solution) it's returning values! It's returning 360 instead of 1 but It does not matter it's working afer 3 days of fighting with it!
So now it's look like this
when I compile it with VS it's working and returning value to C# and I know that VS dubbuger has SH** value because it show no changes in XMM registersand it shows that in EAX is 168 but it returns 360 (when I put only one instruction MOV eax,12 it returns 12 so I thing its debugger showing sth wrong)
OllyDGB some assembler code but it completly don't look like mine (matter if I compile it in debug mode?)
when I compile the same code by QEditor using Makeit.bat it don't work with C# (exception is thrown) but in OllyDGB I see my code but I don't know how tu put parameters tu the procedure when using Call DLL export (it says only integer values can be put)
So I have pretty working code but I have no idea how tu debug it XD
Quote from: Orzel94 on January 23, 2017, 01:12:34 AMin EAX is 168 but it returns 360
168 is the hex representation of 360 decimal. Olly shows hex most of the time, except if the values have a dot, like 123
.If you want symbols in the debugger:
; OPT_Symbols 1 ; for RichMasm, somewhere in the source
Otherwise, add
/Zi /Zf to the assembler,
/debug to the linker commandline
There are not many symbols to see in the debugger, but if the symbols work properly, you will see for example:
72E81095 660F2FE2 comisd xmm4, xmm2
72E81099 77 C7 ja short 72E81062
72E8109B B8 68010000 mov eax, 168
72E810A0 391D 0040E872 cmp [circle], ebx ; <<<<<<<<<<<<<<<<<<<<<<<<
72E810A6 7F BA jg short 72E81062
72E810A8 8BC3 mov eax, ebx
72E810AA 5B pop ebx
72E810AB 5D pop ebp
72E810AC C3 retnNote the mov eax, 168 - it's 360, of course. Now that the building and testing process is OK, maybe it's time to look at the code again? ;-)
aproxASM_stdcall proc stdcall export uses ebx p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
xor eax, eax ; zero
movlpd xmm4, four
movlpd xmm0, p_real
movlpd xmm1, p_imaginary
doloop: ; real_part
inc eax ; loop indexer
vmulsd xmm2, xmm0, xmm0
vmulsd xmm3, xmm1, xmm1
subsd xmm2, xmm3
addsd xmm2, c_real
; imaginary_part
vmulsd xmm3, xmm0, xmm1
addsd xmm3, xmm3
addsd xmm3, c_imaginary
movsd xmm0, xmm2
movsd xmm1, xmm3
; complexMod
vmulsd xmm2, xmm0, xmm0
vmulsd xmm3, xmm1, xmm1
addsd xmm2, xmm3
; while (modulo < 4 && i < 360);
comisd xmm4, xmm2
ja doloop
cmp circle, 360 ; makes no sense at all, circle is DD 360!
jg doloop
ret
aproxASM_stdcall endp
here it's how the code looks now
;-------------------------------------------------------------------------
.686
.MMX
.XMM
.MODEL FLAT, STDCALL
OPTION CASEMAP:NONE
.DATA
circle DD 360
.CODE
LibMain proc instance:DWORD, reason:DWORD, unused:DWORD
mov eax, 1
ret
LibMain endp
;-------------------------------------------------------------------------
aproxASM proc c export p_real: REAL8, p_imaginary: REAL8, c_real:REAL8, c_imaginary:REAL8, four:REAL8
MOV ecx,0
MOVLPD XMM4,[four]
MOVLPD XMM0,[p_real]
MOVLPD XMM1,[p_imaginary]
do:
;real_part
VMULSD XMM2,XMM0,XMM0
VMULSD XMM3,XMM1,XMM1
SUBSD XMM2,XMM3
ADDSD XMM2,c_real
;imaginary_part
VMULSD XMM3,XMM0,XMM1
ADDSD XMM3,XMM3
ADDSD XMM3,[c_imaginary]
MOVSD XMM0,XMM2
MOVSD XMM1,XMM3
INC ecx ;loop indexer
;complexMod
VMULSD XMM2,XMM0,XMM0
VMULSD XMM3,XMM1,XMM1
ADDSD XMM2,XMM3
;while (modulo < 4 && i < 360);
COMISD XMM4,XMM2
JG second
JMP done
;MOV eax,360
second:
CMP circle,ecx
JG do
done:
MOV eax,ecx
;MOV eax,12
ret
aproxASM endp
end LibMain
this cmp ccircle,360 disapeared earlier
I fix issue with "while" implementation and now its working excatly as code in C (only difference is result i ASM == result in C + ~10 or + ~11 (I thing) I don't know why yet but the only thing it changes it move a little bit color in HSV (instead of red is more orange (i wrote 2D fractal generator)) so I can say to teacher that I have planned it XD )
So thank you very much ;)