Re: Array vs Vector performance

tni <nobody@[EMAIL PROTECTED]
> wrote:
>> There appears to be significant performance difference between the
>> array and the vector.
> 
> This is just the case for Visual C++. For GCC/MinGW, the execution time
> is exactly the same.
> 
> Part of the problem are checked iterators (MS made the poor decision to
> enable them by default; if you disable them, you have to do so in any
> library you link to as well). If they are disabled, the array version is
> still faster. Looking at the assembly code, the array version is really
> clever (twice as fast as a naive assembly version), the vector version
> is lousy. The MingW assembly looks almost like a straightforward
> assembly version I would do.

Out of curiosity: Could you show the three versions of assembly code
- or if this is deemed too much Off Topic - sent them as private mail?
I'd really like to see what halves the time over a "straightforward"
assembly.

{ As used to clarify or discuss C++ implementation issues assembly code
would 
not be off-topic. -mod }


> VC8 array : 937ms
> VC8 vector (checked iterators) : 3484ms
> VC8 vector (checked iterators disabled) : 2391ms
> MinGW 4.1 : 2031ms

Andre'

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