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Re: include/dis-asm.h patch for cgen disassemblers


> Hi -
> 
> cagney wrote:
> 
>> What is the difference between an architecture, isa and machine?
> 
> 
> architecture ~= bfd architecture ~= family of processors


Hmm, archures.c contains:

         This enum gives the object file's CPU architecture, in a
         global sense---i.e., what processor family does it belong to?
         Another field indicates which processor within
         the family is in use.  The machine gives a number which
         distinguishes different versions of the architecture,
         containing, for example, 2 and 3 for Intel i960 KA and i960 KB,
         and 68020 and 68030 for Motorola 68020 and 68030.


> machine ~= bfd machine ~= implementation of an architecture




> isa ~= instruction set ~= group of machine instructions decodable;
>                           can be a function of cpu state


Er, ISA == Instruction Set Architecture which to me is bfd_architecture. 
  I think, here you're looking for something else.

For instance, Arm has thumb and MIPS has MIPS16.  They are modes but 
sill part of a single ISA.

Andrew





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