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Testing Inline ASM-VB
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Using inline ASM
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Testing Inline ASM-VB
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Using inline ASM
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A simple array additionEven with simple things as adding one number to every tiem to the array, VB proves no competition against inline ASM
the simple ASM code easily beats VB with 400%. Also note that if I'd cache the pointer to the array, it would be even higher.
Since then, I only have to call VarPtr only once, instead of every iteration. But I thought this would be more fair "against" VB.
I used an array which contained 20.000 items.
User contributed notes:
the simple ASM code easily beats VB with 400%. Also note that if I'd cache the pointer to the array, it would be even higher.
Since then, I only have to call VarPtr only once, instead of every iteration. But I thought this would be more fair "against" VB.
I used an array which contained 20.000 items.
'//How-to use: Simply call it like: '//Call mdlASM.UpdateArrayASM(VarPtr(myArray(0)), UBound(myArray), lngNumber) '//lngNumber is the number to add to the array. Public Function UpdateArrayASM(ByVal lngPointer As Long, ByVal lngUbound As Long, ByVal lngNumber As Long) As Long '#ASM_START ' push ebp ' mov ebp, esp ' push ecx ' push edx ' push eax ' mov eax, dword ptr[ebp+8] ;Array pointer ' mov ecx, [ebp+12] ;Elements ' mov edx, [ebp+16] ;Number to add ' ;Loop label 'LoopArray: ' add dword ptr[eax], edx ;Add lngNumber to the pointer ' add eax, 4 ;Increase our position in the array (element, steps of 4 because of long) ' ' dec ecx ;Decrease ecx with one (like ecx--) ' jnz LoopArray ;"goto" LoopArray label.. as long as ecx is not zero ' pop eax ' pop edx ' pop ecx ' mov esp, ebp ;MOV/POP is much faster ' pop ebp ;on 486 and Pentium than Leave ' ret 8 '#ASM_END End Function Public Function UpdateArrayVB(myArray() As Long, ByVal lngNumber As Long) As Long Dim Y As Long For Y = 0 To UBound(myArray) myArray(Y) = myArray(Y) + lngNumber Next Y End Function |
| VBArrayAdd % faster than ASMArrayAdd | VBArrayAdd (sec) | ASMArrayAdd (sec) |
| 449.8% | 4.882183 | 0.888067 |
| 350.2% | 4.809162 | 1.068218 |
| 446.4% | 4.831393 | 0.88426 |
| 413.1% | 4.890543 | 0.9531 |
| 441.1% | 4.854989 | 0.89723 |
| VBArrayAdd % faster than ASMArrayAdd | VBArrayAdd (sec) | ASMArrayAdd (sec) |
| 436.4% | 9.784413 | 1.824087 |
| 456.1% | 9.761054 | 1.755358 |
| 450.4% | 9.902339 | 1.799235 |
| 468.8% | 10.117369 | 1.778716 |
| 447.8% | 9.757736 | 1.781121 |
User contributed notes:
| Author: Tom (hurendo_kun at hotmail dot com) | Date: 19:07 14/07/2005 |
| You're only calling VarPtr once, in the initial function call. The value is cached automatically when it's passed ByVal. So, this test is really as fast as it can get. | |
| Author: Percephone () | Date: 15:01 18/01/2009 |
| I think you should distribute the source code or make its location known, Before VB6 becomes extinct. Heck, we might even be able to further the optimization of the library in the public domain. | |