where we weren't accounting for the possibility that a @finally block might
have internal cleanups and therefore might write to the cleanup destination slot.
Fixes <rdar://problem/8293901>.
llvm-svn: 110760
ObjC exceptions:
- don't enter a try for the catch blocks unless there's a finally
- put the setjmp buffer in the locals set for liveness reasons
- dump the sync object into an alloca in the locals set for liveness reasons
Some of this can go away if the backend starts to properly calculate liveness
in the presence of setjmp (which would also be a *much* stabler solution).
llvm-svn: 110188
the magic of inline assembly. Essentially we use read and write hazards
on the set of local variables to force flushing locals to memory
immediately before any protected calls and to inhibit optimizing locals
across the setjmp->catch edge. Fixes rdar://problem/8160285
llvm-svn: 109960
self-host. Hopefully these results hold up on different platforms.
I tried to keep the GNU ObjC runtime happy, but it's hard for me to test.
Reimplement how clang generates IR for exceptions. Instead of creating new
invoke destinations which sequentially chain to the previous destination,
push a more semantic representation of *why* we need the cleanup/catch/filter
behavior, then collect that information into a single landing pad upon request.
Also reorganizes how normal cleanups (i.e. cleanups triggered by non-exceptional
control flow) are generated, since it's actually fairly closely tied in with
the former. Remove the need to track which cleanup scope a block is associated
with.
Document a lot of previously poorly-understood (by me, at least) behavior.
The new framework implements the Horrible Hack (tm), which requires every
landing pad to have a catch-all so that inlining will work. Clang no longer
requires the Horrible Hack just to make exceptions flow correctly within
a function, however. The HH is an unfortunate requirement of LLVM's EH IR.
llvm-svn: 107631
