More on C++ stack arrays

[Iain Buclaw]

On 20 October 2013 20:15, David Nadlinger <code at klickverbot.at> wrote:
> On Sunday, 20 October 2013 at 18:42:06 UTC, Walter Bright wrote:
>>
>> If your optimizing compiler is that good, it can optimize "new T[n]" to be
>> on the stack as well.
>
>
> Just a side note: LDC actually does this if it can prove statically that the
> size is bounded. Unfortunately, the range detection is rather conservative
> (unless your allocation size turns out to be a constant due to inlining,
> LLVM is unlikely to get it).
>
> One idea that might be interesting to think about is to insert a run-time
> check for the size if an allocation is known not to be escaped, but the size
> is not yet determined. As a GC allocation is very expensive anyway, this
> probably wouldn't even be much of a pessimization in the general case.
>

David, can you check the code generation of:

http://dpaste.dzfl.pl/3e333df6


PS:  Walter, looks the above causes an ICE in DMD?


-- 
Iain Buclaw

*(p < e ? p++ : p) = (c & 0x0f) + '0';