This model uses the 'landingpad' instruction, which is pinned to the top of the
landing pad. (A landing pad is defined as the destination of the unwind branch
of an invoke instruction.) All of the information needed to generate the correct
exception handling metadata during code generation is encoded into the
landingpad instruction.
The new 'resume' instruction takes the place of the llvm.eh.resume intrinsic
call. It's lowered in much the same way as the intrinsic is.
llvm-svn: 140049
possible for that to matter right now, but eventually I think we'll
need to unify this better, and then it might. Also, use a more
efficient looping structure.
llvm-svn: 139788
single code path. Use atomic loads and stores where necessary. Load and
store anything of the appropriate size and alignment with primitive
operations instead of going through the call.
llvm-svn: 139580
Use a more portable heuristic for deciding when to emit a single
atomic store; it's possible that I've lost information here, but
I'm not sure how much of the logic before was intentionally arch-specific
and how much was just not quite consistent.
llvm-svn: 139468
emit call results into potentially aliased slots. This allows us
to properly mark indirect return slots as noalias, at the cost
of requiring an extra memcpy when assigning an aggregate call
result into a l-value. It also brings us into compliance with
the x86-64 ABI.
llvm-svn: 138599
hierarchy of delegation, and that EH selector values are meaningful
function-wide (good thing, too, or inlining wouldn't work).
2,3d
1a
hierarchy of delegation and that EH selector values have the same
meaning everywhere in the function instead of being meaningful only
in the context of a specific selector.
This removes the need for routing edges through EH cleanups,
since a cleanup simply always branches to its enclosing scope.
llvm-svn: 137293
- an off-by-one error in emission of irregular array limits for
InitListExprs
- use an EH partial-destruction cleanup within the normal
array-destruction cleanup
- get the branch destinations right for the empty check
Also some refactoring which unfortunately obscures these changes.
llvm-svn: 134890
- Emit default-initialization of arrays that were partially initialized
with initializer lists with a loop, rather than emitting the default
initializer N times;
- support destroying VLAs of non-trivial type, although this is not
yet exposed to users; and
- support the partial destruction of arrays initialized with
initializer lists when an initializer throws an exception.
llvm-svn: 134784
retain/release the temporary object appropriately. Previously, we
would only perform the retain/release operations when the reference
would extend the lifetime of the temporary, but this does the wrong
thing across calls.
llvm-svn: 133620
existence by always threading an edge from the catchall. Not doing
this was previously causing a crash in the very extreme case where
neither the normal cleanup nor the EH catchall was actually reachable:
we would delete the catchall entry block, which would cause us to
delete the entry block of the finally cleanup as well because the
cleanup logic would merge the blocks, which in turn triggered an assert
because later blocks in the finally would still be using values from the
entry. Laziness turns out to be the most elegant solution to the problem.
llvm-svn: 133601
MaterializeTemporaryExpr captures a reference binding to a temporary
value, making explicit that the temporary value (a prvalue) needs to
be materialized into memory so that its address can be used. The
intended AST invariant here is that a reference will always bind to a
glvalue, and MaterializeTemporaryExpr will be used to convert prvalues
into glvalues for that binding to happen. For example, given
const int& r = 1.0;
The initializer of "r" will be a MaterializeTemporaryExpr whose
subexpression is an implicit conversion from the double literal "1.0"
to an integer value.
IR generation benefits most from this new node, since it was
previously guessing (badly) when to materialize temporaries for the
purposes of reference binding. There are likely more refactoring and
cleanups we could perform there, but the introduction of
MaterializeTemporaryExpr fixes PR9565, a case where IR generation
would effectively bind a const reference directly to a bitfield in a
struct. Addresses <rdar://problem/9552231>.
llvm-svn: 133521
they should still be officially __strong for the purposes of errors,
block capture, etc. Make a new bit on variables, isARCPseudoStrong(),
and set this for 'self' and these enumeration-loop variables. Change
the code that was looking for the old patterns to look for this bit,
and change IR generation to find this bit and treat the resulting
variable as __unsafe_unretained for the purposes of init/destroy in
the two places it can come up.
llvm-svn: 133243
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
to be careful to emit landing pads that are always prepared to handle a
cleanup path. This is correct mostly because of the fix to the LLVM
inliner, r132200.
llvm-svn: 132209
As far as I know, this implementation is complete but might be missing a
few optimizations. Exceptions and virtual bases are handled correctly.
Because I'm an optimist, the web page has appropriately been updated. If
I'm wrong, feel free to downgrade its support categories.
llvm-svn: 130642
__block object copy/dispose helpers for C++ objects with those for
different variables with completely different semantics simply because
they happen to both be no more aligned than a pointer.
Found by inspection.
Also, internalize most of the helper generation logic within CGBlocks.cpp,
and refactor it to fit my peculiar aesthetic sense.
llvm-svn: 128618
simplify the logic of initializing function parameters so that we don't need
both a variable declaration and a type in FunctionArgList. This also means
that we need to propagate the CGFunctionInfo down in a lot of places rather
than recalculating it from the FAL. There's more we can do to eliminate
redundancy here, and I've left FIXMEs behind to do it.
llvm-svn: 127314
