? (0xe2.0x9a.0x9b@gmail.com) on 6/24/10 wrote:
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>Gabriele Svelto (gabriele.svelto@gmail.com) on 6/23/10 wrote:
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>>As for optimizations effort there's been
>>a lot going on in GCC and both its baseline and peak performance have improved a
>>lot (at least in the applications I care about) even if some features were integrated very late (LTO!).
>
>1. My impression is that the Linux programs typically found in a Linux distribution
>have approximately the *same* performance regardless of whether they are compiled
>with GCC 3.4, 4.0, 4.1, 4.2, 4.3, 4.4 or 4.5. As another example, when I switched
>my application from GCC 4.4 to GCC 4.5 I did *not* notice any significant performance
>boost. Is your experience different?
>
>2. As far as my experience goes, LTO:
>
>- does not bring about the expected results (assembler code)
>- is buggy
>
>Again, is your experience with LTO different? I don't mean guesswork, I mean experience.
>
>-----
>
>Bottom line: Not counting the support for new C/C++ features, how exactly is GCC 4.5 better than GCC 3.4 ?
>

SSE intrinsics and/or C++ templates improved a lot in 4.2