Compiler optimizations

[Nick B]

Don wrote:
> dsimcha wrote:
>> Does anyone know of a decent guide that has information on what types of
>> optimizations compilers typically perform and what they aren't capable of
>> performing automatically?  I figure it would be useful to know 
>> something like
>> this because, when micro-optimizing performance-critical code, it's 
>> silly to
>> do a low-level optimization that makes the code less readable if the
>> compiler's already probably doing it.  On the other hand, it would be 
>> nice to
>> know exactly what optimizations (besides the obvious stuff like 
>> high-level
>> design and algorithm optimizations) the compiler can't possibly be
>> sufficiently smart to do, so I can spend time looking for 
>> opportunities to do
>> those.
> 
> As always -- Agner Fog. www.agner.org. Chapter 1 of his optimisation 
> manual lists the optimisations performed for Microsoft, Borland, Intel, 
> GCC, DMC, Watcom, and Codeplay C++ compilers. DMD is basically the same 
> as DMC, except that it's better at constant propagation.

Don

Thanks for the great link. The "Optimizing software in C++" is a 
interesting read. It even mentions "D".

Nick B.