DeferCleanup pushes a new temporary cleanup to catch non-local returns
from the defer block, so we have to use stable iterators while emitting
cleanups.
There's no good deterministic test case for this -- it would manifest
as memory corruption if the underlying storage of the DiverseStack
grew beyond the inline storage. Add a reduced version of the original
user-reported test case that triggers it reliably -- I had a hard time
coming up with anything simpler.
Fixes <rdar://problem/21437203>.
Swift SVN r29658
The other part of rdar://problem/21444126. This is a little trickier since SIL doesn't track uses of witness tables in a principled way. Track uses in SILGen by putting a "SILGenBuilder" wrapper in front of SILBuilder, which marks conformances from apply, existential erasure, and metatype lookup instructions as used, so we can avoid emitting shared Clang importer witnesses when they aren't needed.
Swift SVN r29544
in terms of the pattern binding/emission facilities that are currently
used for switches. They are more general (handling all patterns,
not hacked up just for optionals).
This leads to us producing better code for if/let bindings, because we
don't alloc_stack a temporary and deal with memory for non-address-only
types (e.g. the common case of an optional pointer). Instead, the code
emits a select_enum{_addr} on the value.
While this changes the generated code in the compiler, there is no exposed
behavioral change to the developer.
Swift SVN r26142
rdar://problem/19450969
Undo reverts r24381..24384 with one fix: pull cleanup blocks from the
back of the list. When breaking out of a while loop, an extra release
could over-release a reference.
Swift SVN r24553
completely destroyed when forwarded.
Also, make forwarding a cleanup a first-class operation
on cleanups, rather than setting the cleanup state directly.
Swift SVN r19332
state of a cleanup to be restored after emitting
a path that may have e.g. activated it.
This should be used very carefully, because it makes
it quite simple to foul up your cleanup logic.
To be useful for temporarily deactivating cleanups,
we need a state that prevents forwarding from killing
the cleanup.
Swift SVN r19331
The cleanup stack pointer is not reset when there are only dead cleanups in a scope, so relax this assertion to check that there are no live cleanups instead of that the cleanup handles are at the same height. Fixes <rdar://problem/16203107>.
Swift SVN r14674
I've decided to keep only the location of the scope AST node that corresponds to the cleanup. (Currently, there is no user that needs the originator expression, which caused the cleanup. So keeping things simple.)
Added the cleanup location to the Scope and JumpDest classes, which gets assigned on construction of those. The Scope's and JumpDest locations are used when we emit the cleanup instructions.
We now give better location info for 2 existing tests for definitive initialization.
(+ Rather sparse testing of all this.)
Swift SVN r7764
We mark the branch instructions leading into single epilog code with ReturnLocation/ImplicitReturnLocation. If SIL Gen simplifies the code and merges the code representing the return into the epilog block, the terminator of the epilog block (the ReturnInst) will have the return location info on it. Otherwise, the ReturnInst has the RegularLocation, which represents the enclosing FunctionExpr or Constructor/Destructor Decls.
(I've discussed dropping the optimization from SILGen, and keeping the epilog code canonical, with Adrian; but he said that there might not be any wins in doing so, so keeping it for now.)
Added AutoGeneratedLocation to represent segments of code generated by SILGen. This will be used for thunks and other auto-generated segments.
Swift SVN r7634
