Peek/Poke commands in assembly?

[Mistrel]

Does anyone know where I can find the ASM equivalents of the Peek/Poke commands for long, float, and string?

[Trond]

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; PokeL(@A, 7)
!mov [v_a], 7

; PokeL(A, 7)
!mov eax, [v_a]
!mov [eax], 7

; PokeF(@F, 7)
!mov [v_f], 1088421888

Peek is the same, you just mov the other way. For strings there's a loop to PokeB() the individual characters.

[Mistrel]

I don't know assembly well at all but isn't this the correct way to mov a variable?

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!mov eax,[v_a]
!mov [eax],dword 7

[Trond]

I prefer "!mov dword [eax], 7", but that two-step way is if the variable is a pointer, so you move 7 into the address pointed to by a.

[Psychophanta]

there is another way often used in z80 times:

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A.l
;PokeL(@A,-789):
!push dword -789
!pop dword[v_A]
Debug A.l

b.q
;PokeQ(@b,-123789):
!push dword -1 dword -123789
!pop dword[v_b] dword[v_b+4]
Debug b.q

[Trond]

There's no reason to use push when you can use mov, as it's way faster.

[Trond]

Here's the full PokeL function by the way:

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!mypokel2: ; (Address+4, Value+8)
!mov  edx, [esp+4]
!mov  eax, [esp+8]
!mov  [edx], eax
!ret  8

; PokeL(@A, 7)
  !pushd 7
  !push v_a
  !call mypokel2

; PokeL(A, 7)
  !pushd 7
  !pushd [v_a]
  !call mypokel2

[Psychophanta]

Indeed you are right 'mov' is faster than using stack, so there should be an improvement to redesign the way PB performs Poke and Peek.

[superadnim]

Why the need to repost?
http://www.purebasic.fr/english/viewtopic.php?t=29895

I thought people gave good answers in there, enough to implement my own peek/poke set in asm x86 without trouble.

But anyway, for string you will have to ask yourself "do I want to support unicode?", then try about coding it.

[Mistrel]

Why the need to repost?
http://www.purebasic.fr/english/viewtopic.php?t=29895

I thought people gave good answers in there, enough to implement my own peek/poke set in asm x86 without trouble.

But anyway, for string you will have to ask yourself "do I want to support unicode?", then try about coding it.

That post did not cover floats or strings.

[Trond]

Floats are exactly the same as longs - 4 bytes. Only the interpretation of the contents is different.