Re: help sought, possible asm/cpu/other problem???

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#235

From: Bob Gonder
Date: Thu, 17 Jul 2008 00:15

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1770 bytes

Dennis Cote wrote:

>>          lahf
>>     if(!(_EAX & 0x4000)) //0x40 set in AH
>
>I think you are using the wrong constant. LAHF loads the 16 bit flags 
>register into AH.

That would be hard to do as AH only has 8 bits.

> The zero flag is bit 6 in this register. To compare 

Correct.

>using EAX the extended 32 bit register you need to shift your mask, 
>0x0040 left by 16 bits to give 0x00400000.

Not correct.
AL is bits 0-7 of EAX.
AH is bits 8-15 of EAX ( 0x0100 to 0x8000 )
Bits 16-31 of EAX are not addressable.

The original code is correct for zf.
Though with all the assembly, it would
be clearer to continue with ASM.

         mov   edi, pAddr
         repe  scasb
         je return0
	};//end asm
        if(!MM3AdminData.survivalmode)
            if(MM3AdminData.callint3onerror) __asm int 3 ;
         return 1 ;
 return0:
	return 0;

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From: Bob Gonder <none@nowhere.invalid>
Newsgroups: borland.public.cppbuilder.nativeapi
Subject: Re: help sought, possible asm/cpu/other problem???
Date: Wed, 16 Jul 2008 17:15:33 -0700
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