[PATCH] ADT: Remove misaligned pointeres from DenseMapInfo

[Alexey Samsonov]

Ping.

On Fri, Jan 2, 2015 at 6:41 PM, Alexey Samsonov <vonosmas at gmail.com> wrote:

> So, what do you think will be the correct resolution for this?
>
> On Mon, Dec 29, 2014 at 5:45 PM, Alexey Samsonov <vonosmas at gmail.com>
> wrote:
>
>> On Mon, Dec 29, 2014 at 5:41 PM, Chandler Carruth <chandlerc at gmail.com>
>> wrote:
>>
>>>
>>> On Mon, Dec 29, 2014 at 5:33 PM, Alexey Samsonov <vonosmas at gmail.com>
>>> wrote:
>>>
>>>> Casing (int*) to (float*) doesn't dereference a pointer. However,
>>>> upcast/downcast (in general case) does dereference a pointer - you may need
>>>> to read vtable and adjust the pointer value accordingly.
>>>
>>>
>>> I see, so the problem is we're up casting or down casting? I suspect
>>> such casts can be avoided? We should only be casting between integers and a
>>> single pointer type in the dense map stuff...
>>>
>>
>> If we have smth. like DenseMap<AssertingVH<T>, Foo> (or other ValueHandle
>> kinds), we would cast empty/tombstone keys (i.e. fake pointers) for T* to
>> Value*.
>>
>> --
>> Alexey Samsonov
>> vonosmas at gmail.com
>>
>
>
>
> --
> Alexey Samsonov
> vonosmas at gmail.com
>



-- 
Alexey Samsonov
vonosmas at gmail.com
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