With the Flash Player 10, Adobe added a new set of instructions allowing to compile C/C++ in a way the AVM2 could execute. By wrapping a little bit of glue code in C, Alchemy allows to reuse some of the numerous open source C libraries available.
And when you appreciate the speed of Alchemy-compiled C code, you can wonder how it can possibly be so much faster than AS3. Unfair!
What makes Alchemy code so fast? The main secret is a faster memory management, because obviously C/C++ is all about pointers & malloc’ing. ByteArray in AS3 is kind of slow so Adobe had to hack the AVM2 to remove this bottleneck or Alchemy would have been pointless.
And the good news for us AS3 geeks is that it is possible to use this fast memory in AS3…