Re: optimized code


"Daniel O'Connell [C# MVP]" <onyxkirx@xxxxxxxxxxxxxxxxxxxxx> wrote in
message news:eNZ5Ljq%23FHA.1676@xxxxxxxxxxxxxxxxxxxxxxx
>
> "Mike" <vimakefile@xxxxxxxxx> wrote in message
> news:Oj7acNp%23FHA.2424@xxxxxxxxxxxxxxxxxxxxxxx
>> Is it still true that the managed C++ compiler will produce much better
>> opimizations than the C# compiler, or have some of the more
>> global/aggressive opimizations been rolled into the 2005 compiler?
>>
>
> Yes, the Managed C++ compiler should still be better. the C# compiler
> still doesn't go very far as far as optimizations go, AFAIK anyway. They
> are left to the JIT.
>
>
The same applies to the "managed C++" compiler, common sub-expressions and
loop invariants are handled by the JIT not by the compiler fron-ends.
The managed C++ compiler generates IL, sometimes it does a better job, but
I've seen IL code that was better optimized by the C# compiler. Anyway the
differences are < 5% (both sides), MS said that they will focus on the JIT
to further optimize, not in the C++ front-end.


Willy.


.

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