Re: Reverse in std_vector.hh

[Han-Wen Nienhuys]

Ruud van Silfhout wrote:
> Hi,
>
> I have made an extension for the reverse function in std_vector.hh. The 
> code suggests to implement template specialisation for reverse vector<int>.
> This is what I have done, plus specialisation for float and double vectors.
> The code depends on the availability of memrev, which is not available 
> on all platforms.So a check is required (during configure) to 

on which platforms is it available?

address@hidden ~]$ grep memrev /usr/include/* /usr/include/c++/4.1.1/*/*
address@hidden ~]$

> In case memrev is not available there are two options:
> 1. skip the specialized template implementation for <int> <float> 
> <double> and keep the generic template code. This is what is implemented 
> now.
> 2. implement a replacement for memrev. a simple replacement is added 
> below. I don't know where to put it.

libc-extension.cc seems like a good place.

> it uses malloc to allocate memory for each item. This can also be done 
> using alloca, which allocates memory on the stack and, as a consequence, 

Why not simply swap byte by byte in an inner loop?

--

Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwen

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