On Tuesday, 28 May 2013 at 13:33:39 UTC, Steven Schveighoffer
wrote:
I asked David Nadlinger at the conference whether we could
leverage this power in LDC, since LLVM is the compiler back-end
used by Apple, but he said all those optimization passes are in
the Objective-C front-end.
Hm, apparently I was imprecise or I slightly misunderstood your
question:
The actual optimizations _are_ done in LLVM, and are part of its
source tree (see lib/Transforms/ObjCARC). What I meant to say is
that they are tied to the ObjC runtime function calls emitted by
Clang – there is no notion of a "reference counted pointer" on
the LLVM level.
Thus, we could definitely base a similar implementation D on
this, which would recognize D runtime calls (potentially
accompanied by D-specific LLVM metadata) instead of Objective-C
ones. It's just that there would be quite a bit of adjusting
involved, as the ObjC ARC implementation isn't designed to be
language-agnostic.
David
