Re: -Os versus -O2

From: Rene Herman
Date: Sun Jun 24 2007 - 21:35:06 EST


On 06/25/2007 03:23 AM, Rene Herman wrote:

On 06/25/2007 02:41 AM, Adrian Bunk wrote:

The interesting questions are:
Does -Os still sometimes generate faster code with gcc 4.2?
If yes, why?

I would wager that the CPU type makes more of a difference than the compiler version. That is, I'd expect my Duron with it's "puny" 64K L1 to have a very different profile than it's Athlon brother with 256K L1.

Sorry, that should've been L2. And "its" ...

> Not to mention CPUs with as little as 8K L1 (P1).

I can't quote numbers -- it's a bit hard to test those things anyway as it's a system-global effect and not su much that's easily isolated in a dedicated benchmark.

And while I'm at it, "and not so much one that's [ ...]".

Rene.
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