Improving performance of byte pointer copy

[infratec]

Copy is working:

Code: Select all

EnableExplicit


Procedure CopyMemoryOso(*src, *dest, len.i)
  
  Structure TypeArray_Structure
    StructureUnion
      a.a
      u.u
      l.l
      q.q
    EndStructureUnion
  EndStructure
  
  Protected CopyLen.i
  Protected.TypeArray_Structure *srcptr, *destptr
  
  
  *srcptr  = *src        ; Set starting pointer
  *destptr = *dest       ; Set destination pointer
  
  CopyLen = len
  While CopyLen
    If CopyLen > 8
      *destptr\q = *srcptr\q      ; Copy the character
      *srcptr + 8                 ; Advance source pointer
      *destptr + 8                ; Advance destination pointer
      CopyLen - 8
    ElseIf CopyLen > 4
      *destptr\l = *srcptr\l      ; Copy the character
      *srcptr + 4                 ; Advance source pointer
      *destptr + 4                ; Advance destination pointer
      CopyLen - 4
    ElseIf CopyLen > 2
      *destptr\u = *srcptr\u      ; Copy the character
      *srcptr + 2                 ; Advance source pointer
      *destptr + 2                ; Advance destination pointer
      CopyLen - 2
    Else
      *destptr\a = *srcptr\a      ; Copy the character
      *srcptr + 1                 ; Advance source pointer
      *destptr + 1                ; Advance destination pointer
      CopyLen - 1
    EndIf
  Wend
  
EndProcedure


Define *Src, *Dest
Define t1.q, t2.q

*Src = AllocateMemory(20001, #PB_Memory_NoClear)
PokeQ(*Src, $0123456789ABCDEF)
PokeQ(*Src + MemorySize(*Src) - 8, $FEDCBA9876543210)
*Dest = AllocateMemory(MemorySize(*Src))

DisableDebugger
t1 = ElapsedMilliseconds()
CopyMemoryOso(*Src, *Dest, MemorySize(*Src))
t2 = ElapsedMilliseconds()
EnableDebugger
Debug t2 - t1
ShowMemoryViewer(*Dest, MemorySize(*Src))

[idle]

Copy is working:

Code: Select all

EnableExplicit


Procedure CopyMemoryOso(*src, *dest, len.i)
  
  Structure TypeArray_Structure
    StructureUnion
      a.a
      u.u
      l.l
      q.q
    EndStructureUnion
  EndStructure
  
  Protected CopyLen.i
  Protected.TypeArray_Structure *srcptr, *destptr
  
  
  *srcptr  = *src        ; Set starting pointer
  *destptr = *dest       ; Set destination pointer
  
  CopyLen = len
  While CopyLen
    If CopyLen > 8
      *destptr\q = *srcptr\q      ; Copy the character
      *srcptr + 8                 ; Advance source pointer
      *destptr + 8                ; Advance destination pointer
      CopyLen - 8
    ElseIf CopyLen > 4
      *destptr\l = *srcptr\l      ; Copy the character
      *srcptr + 4                 ; Advance source pointer
      *destptr + 4                ; Advance destination pointer
      CopyLen - 4
    ElseIf CopyLen > 2
      *destptr\u = *srcptr\u      ; Copy the character
      *srcptr + 2                 ; Advance source pointer
      *destptr + 2                ; Advance destination pointer
      CopyLen - 2
    Else
      *destptr\a = *srcptr\a      ; Copy the character
      *srcptr + 1                 ; Advance source pointer
      *destptr + 1                ; Advance destination pointer
      CopyLen - 1
    EndIf
  Wend
  
EndProcedure


Define *Src, *Dest
Define t1.q, t2.q

*Src = AllocateMemory(20001, #PB_Memory_NoClear)
PokeQ(*Src, $0123456789ABCDEF)
PokeQ(*Src + MemorySize(*Src) - 8, $FEDCBA9876543210)
*Dest = AllocateMemory(MemorySize(*Src))

DisableDebugger
t1 = ElapsedMilliseconds()
CopyMemoryOso(*Src, *Dest, MemorySize(*Src))
t2 = ElapsedMilliseconds()
EnableDebugger
Debug t2 - t1
ShowMemoryViewer(*Dest, MemorySize(*Src))

It's a good solution 1st branch will be favored so the additional cmps won't hurt to much.

[Oso]

I've just been testing with random data also and yes it seems to work perfectly.

It seemed to successfully copy any type of raw data, not only strings, hence my earlier question about whether \c could copy passively.

[infratec]

The question is ... why

CopyMemory() is inbuild and working.

[Oso]

The question is ... why

CopyMemory() is inbuild and working.

In some cases I have to manipulate the data, so it isn't always a straight copy.