You can now say
expr_move(?dst, ?src) | expr_assign(?dst, ?src) { ... }
to match both expr_move and expr_assign. The names, types, and number
of bound names have to match in all the patterns.
Closes#449.
This adds support for dropping cleanups for temporary values when they
are moved somewhere else. It then adds wraps most copy operations
(return, put in data structure, box, etc) in a way that will fall back
to a move when it is safe.
This saves a lot of taking/dropping, shaving over a megabyte off the
stage2/rustc binary size.
In some cases, most notably function returns, we could detect that the
returned value is a local variable, and can thus be safely moved even
though it is not a temporary. This will require putting some more
information in lvals.
I did not yet handle function arguments, since the logic for passing
them looked too convoluted to touch. I'll probably try that in the
near future, since it's bound to be a big win.
The duplication of upcalls is due to the fact that the runtime is
shared between stage0/rustc and stage1/rustc. Once snapshots are
updated, they should be de-duplicated.
src/comp/syntax is currently just a sub-module of rustc, but it will,
in the near future, be its own crate. This includes:
- The AST data structure
- The parser
- The pretty-printer
- Visit, walk, and fold
- The syntax extension system
- Some utility stuff that should be in the stdlib*
*) Stdlib extensions currently require a snapshot before they can be
used, and the win build is very broken right now. This is temporary
and will be cleaned up when one of those problems goes away.
A lot of code was moved by this patch, mostly towards a more organized
layout. Some package paths did get longer, and I guess the new layout
will take some getting used to. Sorry about that!
Please try not to re-introduce any dependencies in syntax/ on any of
the other src/comp/ subdirs.
