Re: -Os versus -O2

From: Rene Herman <rene.herman@xxxxxxxxx>
Date: Mon, 25 Jun 2007 03:41:08 +0200

On 06/25/2007 03:33 AM, david@xxxxxxx wrote:

is the list of what's included in -O2 vs -Os different for different CPU's? what about within a single family of processors? (even in the x86 family the costs of jumps, loops, and cache misses varies drasticly)

At least not in the example Duron/Athlon case. Both -march=athlon{,-4) but 64K versus 256K L2 which I'd expect to be an important difference in the -Os versus -O2 behaviour.

Rene.
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References:
- [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Denis Cheng
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Oleg Verych
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: rae l
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Oleg Verych
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Arjan van de Ven
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Benjamin LaHaise
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Arjan van de Ven
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Benjamin LaHaise
- Re: [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization
  - From: Arjan van de Ven
- -Os versus -O2
  - From: Adrian Bunk
- Re: -Os versus -O2
  - From: Arjan van de Ven
- Re: -Os versus -O2
  - From: david
- Re: -Os versus -O2
  - From: Arjan van de Ven
- Re: -Os versus -O2
  - From: david

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