[fixed] fastcall macro issue

flat assembler
Message board for the users of flat assembler.

Index > Macroinstructions > [fixed] fastcall macro issue

Author

Thread

murder

Joined: 03 Nov 2011
Posts: 14

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]

27 Jul 2023, 12:06

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20309
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.

27 Jul 2023, 12:14

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
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.

27 Jul 2023, 12:31

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
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.

27 Jul 2023, 12:37

murder

Joined: 03 Nov 2011
Posts: 14

murder 27 Jul 2023, 12:45

WOW! You fixed it so fast! thanks a lot.

27 Jul 2023, 12:45

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8351
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].

27 Jul 2023, 12:56

< Last Thread | Next Thread >

Forum Rules:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum