need to provide a 'dominating IP' which is guaranteed to
dominate the (de)activation point but which cannot be avoided
along any execution path from the (de)activation point to
the push-point of the cleanup. Using the entry block is
bad mojo.
llvm-svn: 144276
a previously-inactive cleanup, not only do we need a
flag variable, but we should also force the cleanup to
query the flag variable. However, we only need to do
this when we're activating in a context that's
conditionally executed; otherwise, we may safely
assume that the cleanup is dominated by the activation
point.
llvm-svn: 144271
full-expression. Naturally they're inactive before we enter
the block literal expression. This restores the intended
behavior that blocks belong to their enclosing scope.
There's a useful -O0 / compile-time optimization that we're
missing here with activating cleanups following straight-line
code from their inactive beginnings.
llvm-svn: 144268
block-typed __block variables using objc_retainBlock
and objc_dispose. Previously we were using
_Block_object_assign and _Block_object_destroy
with BLOCK_BYREF_CALLER, which causes the runtime
to completely ignore the retain and release.
In most cases this doesn't cause catastrophe
because the retain/release are balanced and
because the block in the variable was copied
upon assignment there. However, the stack
copy of the variable will be released when
it goes out of scope, which is a problem if
that value was released due to an assignment
to the heap copy. Similarly, a leak can occur
if the variable is assigned after the copy to
the heap.
llvm-svn: 144162