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Index > Compiler Internals > About FSAVE encoding

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Joined: 04 Mar 2008
Posts: 563
Location: Germany
After reading this,
i find it ok the reason, because of Fasm basic data types as definded in the manual. For FSAVE, for example
super_data db 94 dup (0) ; or 108
     db 94 dup (0)

   FSAVE [super_pointer] ;ok
   FSAVE [super_data]    ;err invalid operand

but,as you know,for example,
  FSAVE [EAX] ;ok
  FSAVE [EBP*4+EAX] ;ok
 ; ... etc... ok

because,actually, after having been opcoded, all of the (16/32) 256 type of MOD/RM could be used,(excluded MOD=11 i guess) depending only on the actual operand size

So, i had been thinking for a while..., Very Happy
why not simply
  FSAVE super_data

it is to say, avoiding type-checking in the declaration of super_data, because it is always implicitly depending on the operand size 66 or not 66 ?
Very Happy
Post 16 Jan 2010, 11:54
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