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zolkefli



Joined: 05 Mar 2005
Posts: 12
zolkefli 29 Mar 2006, 07:18
I look in FAQ but can find. This is a very simple why.
I try to use 64bit floating point. so I declare

var dq 0.0

then when I try to use the variable like this

MOV qword[var],123.3454

Its error. Where I done wrong.
Post 29 Mar 2006, 07:18
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vid
Verbosity in development


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vid 29 Mar 2006, 07:21
there just isn't such instruction. processor doesn't have one.
Post 29 Mar 2006, 07:21
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Reverend



Joined: 24 Aug 2004
Posts: 408
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Reverend 29 Mar 2006, 09:17
in 32-bit procedure you can move immediately only one dword. But you can try:
Code:
pushq 123.3454
movq mm0, qword [esp]
movq qword [var], mm0
add esp, 8

; or
pushq 123.3454
fld qword [esp]
fstp qword [var]
add esp, 8    
It is also possible to create macro which will convert such mov with qword as operand to two movs.
Post 29 Mar 2006, 09:17
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zolkefli



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Posts: 12
zolkefli 29 Mar 2006, 10:05
thanks
Post 29 Mar 2006, 10:05
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zolkefli



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zolkefli 29 Mar 2006, 11:27
I try

pushq 123.345

error pushq not valid instruction
Post 29 Mar 2006, 11:27
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vid
Verbosity in development


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Location: Slovakia
vid 29 Mar 2006, 13:23
you can use more advanced features:
Code:
macro movq destptr, value
{
   local ..LO, ..HO
   virtual at 0
      dq 123.456
      load ..LO dword from 0
      load ..HO dword from 4
   end virtual
   mov ptr dest, ..LO
   mov ptr dest+4, ..HO
}
dq var
...
movq var, 123.456
    

(not tested, but idea is there)
Post 29 Mar 2006, 13:23
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UCM



Joined: 25 Feb 2005
Posts: 285
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UCM 29 Mar 2006, 21:29
vid wrote:
you can use more advanced features:
Code:
macro movq destptr, value
{
   local ..LO, ..HO
   virtual at 0
      dq 123.456
      load ..LO dword from 0
      load ..HO dword from 4
   end virtual
   mov ptr dest, ..LO
   mov ptr dest+4, ..HO
}
dq var
...
movq var, 123.456
    

(not tested, but idea is there)


you mean:
Code:
macro movq destptr, value
{
   local ..LO, ..HO
   virtual at 0
      dq value ;not 123.456
      load ..LO dword from 0
      load ..HO dword from 4
   end virtual
   mov [dest], ..LO
   mov [dest+4], ..HO
}
dq var
...
movq var, 123.456
    

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Post 29 Mar 2006, 21:29
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vid
Verbosity in development


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Location: Slovakia
vid 30 Mar 2006, 00:54
yup, that's it. And i think ptr would work too Wink
Post 30 Mar 2006, 00:54
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Reverend



Joined: 24 Aug 2004
Posts: 408
Location: Poland
Reverend 30 Mar 2006, 22:03
Yes, that's a great idea, but don't forget that movq is an instruction and your macro overloads it making original one unachievable (eg. movq mm0, qword [esp])

pushq works similar as the movq macro above. I thought it was in official win32ax include, but maybe I'm wrong
Post 30 Mar 2006, 22:03
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RedGhost



Joined: 18 May 2005
Posts: 443
Location: BC, Canada
RedGhost 31 Mar 2006, 05:56
Reverend wrote:
Yes, that's a great idea, but don't forget that movq is an instruction and your macro overloads it making original one unachievable (eg. movq mm0, qword [esp])

pushq works similar as the movq macro above. I thought it was in official win32ax include, but maybe I'm wrong


Code:
match pushd =double num,pushd value \{ \local ..high,..low
   virtual at 0
    dq num
    load ..low dword from 0
    load ..high dword from 4
   end virtual
   push ..high
   push ..low
   pushd equ \}
    

and
Code:
 match pushd =double =ptr var,pushd value \{
   push dword [var+4]
   push dword [var]
   pushd equ \}
    


are both from win32ax, so you are indeed correct

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Post 31 Mar 2006, 05:56
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vid
Verbosity in development


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vid 31 Mar 2006, 07:55
Reverend: you are right, i forgot there is a movq instruction, i don't play with MMX/SSE stuff a lot. This macro should have another name.
Post 31 Mar 2006, 07:55
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Reverend



Joined: 24 Aug 2004
Posts: 408
Location: Poland
Reverend 31 Mar 2006, 13:42
zolkefli: According to RedGhost's post and FASM macro, you don't write 'pushq 123.345' but 'push double 123.345' instead.
Post 31 Mar 2006, 13:42
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UCM



Joined: 25 Feb 2005
Posts: 285
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UCM 01 Apr 2006, 02:23
or... pushd double 123.345
Post 01 Apr 2006, 02:23
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