Am 19.01.2018 um 21:08 schrieb J. Gareth Moreton: > Hi everyone, > > So unless anyone has any objections, I would like to start experimenting to > implement a feature that allows > for per-type data alignment. The main purpose for this is to better support > x86-64 SIMD extensions, where > aligned data is far faster to process. While there is a compiler directive > that enforces byte alignment, > this risks causing conflicts with third party units and is a bit much of a > demand for a programmer wishing > to use an SIMD-tuned unit, say. > > Bug/feature details: https://bugs.freepascal.org/view.php?id=32780 > > The format would be as follows: > > type TypeName = TypeInfo [align ByteAmount]; > > The syntax for declaring a type is exactly the same, with a new optional > "align" keyword before the > terminating semicolon. "ByteAmount" has to be a power of 2, which I will > probably limit to 128 currently, > just so it doesn't cause ridiculous or malicious memory usage. There will > probably have to be a minimum > alignment as well, although this will probably just be automatically enforced > (e.g. Single is always aligned > on a 4-byte boundary minimum). > > The intention here is that this feature will be a stepping stone for properly > supporting vectorisation, > implementing some form of the "M128" and "M256" types, and the "vectorcall" > compiler directive for Windows.
In r38020 I committed a fix and an example tm128 how these records (m128/m256) can be implemented properly without any additional suffix. Please give it a try. _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
