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Re: How to correctly determine a small object?
From: |
David Chisnall |
Subject: |
Re: How to correctly determine a small object? |
Date: |
Fri, 7 Jun 2013 21:10:23 +0100 |
On 7 Jun 2013, at 16:29, Luboš Doležel <address@hidden> wrote:
> for toll-free bridging in CoreBase, I need a way to detect whether the
> incoming pointer is a small object encoded in a pointer and act accordingly
> (treat it as an ObjC object and avoid reading it).
In objc/runtime.h, there is a constant SMALL_OBJECT_MASK. If ptr &
SMALL_OBJECT_MASK == 0, then the pointer is not a small object.
On 32-bit platforms, the low bit of the pointer will be 0. On 64-bit
platforms, the low 3 bits will always be zero.
David
- How to correctly determine a small object?, Luboš Doležel, 2013/06/07
- Re: How to correctly determine a small object?, Stefan Bidi, 2013/06/07
- Re: How to correctly determine a small object?,
David Chisnall <=
- Re: How to correctly determine a small object?, David Chisnall, 2013/06/07
- Re: How to correctly determine a small object?, Luboš Doležel, 2013/06/08
- Re: How to correctly determine a small object?, Maxthon Chan, 2013/06/08
- Re: How to correctly determine a small object?, David Chisnall, 2013/06/08
- Re: How to correctly determine a small object?, Chan Maxthon, 2013/06/08
- Re: How to correctly determine a small object?, Ivan Vučica, 2013/06/08
- Re: How to correctly determine a small object?, Chan Maxthon, 2013/06/08
- Re: How to correctly determine a small object?, Ivan Vučica, 2013/06/08
- Re: How to correctly determine a small object?, Chan Maxthon, 2013/06/08
- Re: How to correctly determine a small object?, David Chisnall, 2013/06/09