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Index > Macroinstructions > [fixed] fastcall macro issue

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murder



Joined: 03 Nov 2011
Posts: 13
murder 27 Jul 2023, 12:06
fastcal macro for this code
Code:
fastcall 0,dword[rax+r8]    

will be generate this and throw a error
Code:
mov cl,dword[rax+r8]    


but for this code all works right
Code:
fastcall 0,qword[rax+r8]    
Post 27 Jul 2023, 12:06
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 20137
Location: In your JS exploiting you and your system
revolution 27 Jul 2023, 12:14
Code:
use64
include 'win64a.inc'
fastcall 0,dword[rax+r8]    
Code:
flat assembler  version 1.73.31  (16384 kilobytes memory)
test.asm [3]:
fastcall 0,dword[rax+r8]
<path>/proc64.inc [130] fastcall [122]:
          mov cl,param
<path>/proc64.inc [130] match [74]:
          mov cl,param
processed: mov cl,dword[rax+r8]
error: operand sizes do not match.    
Post 27 Jul 2023, 12:14
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 8344
Location: Kraków, Poland
Tomasz Grysztar 27 Jul 2023, 12:31
The same source does assemble correctly with fasm2 (which uses the "fastcall" macro from the basic fasm compatibility package for fasmg). It is a bug in the old macro.
Post 27 Jul 2023, 12:31
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 8344
Location: Kraków, Poland
Tomasz Grysztar 27 Jul 2023, 12:37
Changing the line 76 of PROC64.INC:
Code:
         if opcode = 67h | opcode = 41h    
to include one more case:
Code:
         if opcode = 67h | opcode = 41h | opcode = 42h    
seems to correct the issue. I'm updating the fasmw package.
Post 27 Jul 2023, 12:37
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murder



Joined: 03 Nov 2011
Posts: 13
murder 27 Jul 2023, 12:45
WOW! You fixed it so fast! thanks a lot.
Post 27 Jul 2023, 12:45
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Tomasz Grysztar



Joined: 16 Jun 2003
Posts: 8344
Location: Kraków, Poland
Tomasz Grysztar 27 Jul 2023, 12:56
I updated the package with an extended fix:
Code:
         if opcode = 67h | ( opcode > 40h & opcode < 48h )    
Otherwise similar bugs would happen for other combinations of registers like [r8+r9].
Post 27 Jul 2023, 12:56
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