Commit Graph

13 Commits

Author SHA1 Message Date
Fariborz Jahanian fbd19749a3 objective-C arc: load of a __weak object happens via call to
objc_loadWeak. This retains and autorelease the weakly-refereced
object. This hidden autorelease sometimes makes __weak variable alive even
after the weak reference is erased, because the object is still referenced
by an autorelease pool. This patch overcomes this behavior by loading a 
weak object via call to objc_loadWeakRetained(), followng it by objc_release
at appropriate place, thereby removing the hidden autorelease. // rdar://10849570

llvm-svn: 168740
2012-11-27 23:02:53 +00:00
John McCall e68b8f4dcc At -O0, prefer objc_storeStrong with a null new value to the
combination of a load+objc_release;  this is generally better
for tools that try to track why values are retained and
released.  Also use objc_storeStrong when copying a block
(again, only at -O0), which requires us to do a preliminary
store of null in order to compensate for objc_storeStrong's
assign semantics.

llvm-svn: 166085
2012-10-17 02:28:37 +00:00
John McCall e63abb5d2b Fix a subtle bug with cleanups: when activating
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
2011-11-10 09:22:44 +00:00
John McCall 08ef466048 Enter the cleanups for a block outside the enclosing
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
2011-11-10 08:15:53 +00:00
John McCall 9b0a7cea0f Make -fobjc-nonfragile-abi the -cc1 default, since it's the
increasingly prevailing case to the point that new features
like ARC don't even support the fragile ABI anymore.

This required a little bit of reshuffling with exceptions
because a check was assuming that ObjCNonFragileABI was
only being set in ObjC mode, and that's actually a bit
obnoxious to do.

Most, though, it involved a perl script to translate a ton
of test cases.

Mostly no functionality change for driver users, although
there are corner cases with disabling language-specific
exceptions that we should handle more correctly now.

llvm-svn: 140957
2011-10-02 01:16:38 +00:00
John McCall 91e82dd477 The continue label in an ARC for-in loop should not involve
releasing the collection.

llvm-svn: 136949
2011-08-05 00:14:38 +00:00
John McCall 538482373b Clean up the analysis of the collection operand to ObjC
for-in statements;  specifically, make sure to close over any
temporaries or cleanups it might require.  In ARC, this has
implications for the lifetime of the collection, so emit it
with a retain and release it upon exit from the loop.

rdar://problem/9817306

llvm-svn: 136204
2011-07-27 01:07:15 +00:00
Chris Lattner 117b724b59 keep track of whether being in a RS_StructPointer state
caused us to skip layout out a function accurately.  If
so, flush the type cache for both the function and struct
case to ensure that any pointers to the functions get
recomputed.  This is overconservative, but with this patch
clang can build itself again.

llvm-svn: 134863
2011-07-10 05:39:13 +00:00
Chris Lattner d1f1158203 Fix the clang bootstrap and Jay's testcase from llvm-dev by being completely
conservative when converting a functiontype to IR when in a "pointer within
a struct" context.  This has the unfortunate sideeffect of compiling all 
function pointers inside of structs into "{}*" which, though correct, is
ugly.  This has the positive side effect of being correct, and it is pretty
straight-forward to improve on this.

llvm-svn: 134861
2011-07-10 03:47:27 +00:00
Chris Lattner a5f58b05e8 clang side to match the LLVM IR type system rewrite patch.
llvm-svn: 134831
2011-07-09 17:41:47 +00:00
John McCall 24fc0decfe Change the driver's logic about Objective-C runtimes: abstract out a
structure to hold inferred information, then propagate each invididual
bit down to -cc1.  Separate the bits of "supports weak" and "has a native
ARC runtime";  make the latter a CodeGenOption.

The tool chain is still driving this decision, because it's the place that
has the required deployment target information on Darwin, but at least it's
better-factored now.

llvm-svn: 134453
2011-07-06 00:26:06 +00:00
John McCall d463132f27 Objective-C fast enumeration loop variables are not retained in ARC, but
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
2011-06-17 06:42:21 +00:00
John McCall 31168b077c Automatic Reference Counting.
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
2011-06-15 23:02:42 +00:00