gnupic: [gnupic] Different hex file generated by gpasm and mpasm
Subject:
Re: [gnupic] Different hex file generated by gpasm and mpasm
From:
Rob Hamerling ####@####.####
Date:
20 Sep 2005 11:07:21 +0100
Message-Id: <432FDF45.4060602@hccnet.nl>
Martyn Welch wrote:
> ----- Original Message ----------
> On Tuesday 20 September 2005 01:11, Chen Xiao Fan wrote:
>
>
>>The file in question is a single relocatable assembly
>>file and I do not expect too much difference in the
>>generated assmebly. Since both are working in the final
>>application, both must be correct. Still I am just
>>a bit curious what is the difference between gpasm
>>and MPASM.
>
>
> One is open source,the other isn't.
>
> As far as I understand, some consideration has been made to keep the syntax
> for gputils the same or at least similar to mpasm. As a result the operation
> of the application should be broadly the same, however gputils is not a
> cloned implementation of mpasm (this assumes the logic used during
> compilation doesn't change between revisions).
An assembler is not a compiler! With an assembler there is a one-to-one
relationship between a source statement and a machine instruction. A
compiler must translate the high level symbolic language to a machine
instructions and it has much freedom how it wants to reach the goal.
> There is more than one way to get the approximately the same point. For
> example, could you tell the difference between these two blocks of code once
> compiled and running?:
>
> 1)
> int main(){
> char i = 0;
> while(i<10){
> print("%d",i);
> i++;
> }
> return(0);
> }
>
> 2)
> int main(){
> char i;
> for(i=0,i<10,i++){
> print("%d",i);
> }
> return(0);
> }
1. Not a fair comparison with assembler!
2. The second example will give compilation errors! ;-)
Regards, Rob.
--
Rob Hamerling, Vianen, NL phone +31-347-322822
homepage: http://www.robh.nl/
