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[Cyan~Fire]

I'm just nearing the end of modding the MERV source for it to compile under MinGW (Dev-C++). I just have one linker error left, and that's with converting the ASM code into AT&T syntax. Here's the code:

Code: Show/Hide Uint32 IMULHIDWORD(Uint32 A, Uint32 B) {    Uint32 HDW;     #ifdef __GNUC__ //Cyan~Fire: Added GCC-style asm     __asm("movl _A, %eax");     __asm("imull _B");     __asm("movl %edx, _HDW"); #else    __asm    {       mov      eax, A       imul   B       mov      HDW, edx    } #endif    return HDW; }

The errors I get are:
algorithms.cpp: undefined reference to `A'
algorithms.cpp: undefined reference to `B'
algorithms.cpp: undefined reference to `HDW'

Anybody know why?

Thanks,
Cyan
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[Mr Ekted]

You can do the same operation if the compiler supports 64-bit operators. In VC this would be something like:

Code: Show/Hide Uint32 IMULHIDWORD(Uint32 A, Uint32 B) { unsigned __int64 product; product = (unsigned __int64)A * (unsigned __int64)B; return ((Uint32)(product >> 32)); }

Of course it's much less efficient unless the compiler is really good at optimization.[/code]
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[Cyan~Fire]

Well I'm trying to leave this code as near to the original as possible... thanks, though.

[Grelminar]

First, that's not a linker error. Second, that's not valid gcc inline asm syntax. This page should help.

[Cyan~Fire]

It was a linker error, but I did solve it now with that site. I had seen a similar site before, but it hadn't addressed how to address (lol) local vars. Thanks

Just for anyone who's curious:

Code: Show/Hide Uint32 IMULHIDWORD(Uint32 A, Uint32 B) {    Uint32 HDW;     #ifdef __GNUC__ //Cyan~Fire: Added GCC-style asm     asm("imull %0" : "=d"(HDW) : "a"(A), "q"(B)); #else    __asm    {       mov      eax, A       imul   B       mov      HDW, edx    } #endif    return HDW; }

So much simpler in GCC...

[Mr Ekted]

MS conforms to Intel ASM spec. That GCC stuff is like reading hex data.

[Cyan~Fire]

Eh, it's easy to read once you understand what it's doing.

[Smong]

You might want to put "memory" in the clober section.

After reading the page that was linked to I am thinking why does this say numwords when the suffix is 'l'?

Code: Show/Hide #define rep_stosl(value, dest, numwords) \ __asm__ __volatile__ ( \   "cld\n\t" \   "rep\n\t" \   "stosl" \   : : "a" (value), "D" (dest), "c" (numwords) \   : "%ecx", "%edi" )

[Cyan~Fire]

I probably should just to be safe, but I've already tested the build and sent the source to Catid, so I think I'll just leave it alone for now.

[Mr Ekted]

[Cyan~Fire]

Yeah, just like C and PERL and ASM and all those other stupid high-level languages! Bah! Let's just write in machine code!!

[Mr Ekted]

Sigh. When you write in ASM, you are trying to talk directly to the machine you are targetting. In the case of Intel/AMD, the instruction set is a known. Trying to disguise instructions with crazy symbols or pretending it's higher level than it is is not helpful. One line, one instruction, one opcode.

[D1st0rt]

Cyan, why write in machine code when you can use 0's and 1's? $$

Some old guy> What?! You had 0's?! Back in my day, we had to use the letter 'O'
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[Mine GO BOOM]

I've actually used someone's machine in which it required you to toggle switches to talk to it. They made their own computer, like back in the original computer type days. Much easier to do now.

[Grelminar]