Michael Gottesman acfb3584c5 [objc-arc-opts] In the presense of an alloca unconditionally remove RR pairs if and only if we are both KnownSafeBU/KnownSafeTD rather than just either or. ... In the presense of a block being initialized, the frontend will emit the objc_retain on the original pointer and the release on the pointer loaded from the alloca. The optimizer will through the provenance analysis realize that the two are related (albiet different), but since we only require KnownSafe in one direction, will match the inner retain on the original pointer with the guard release on the original pointer. This is fixed by ensuring that in the presense of allocas we only unconditionally remove pointers if both our retain and our release are KnownSafe (i.e. we are KnownSafe in both directions) since we must deal with the possibility that the frontend will emit what (to the optimizer) appears to be unbalanced retain/releases. An example of the miscompile is: %A = alloca retain(%x) retain(%x) <--- Inner Retain store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) release(%x) <--- Guarding Release getting optimized to: %A = alloca retain(%x) store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) rdar://13750319 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181743 91177308-0d34-0410-b5e6-96231b3b80d8		2013-05-13 23:49:42 +00:00
..
CMakeLists.txt	Extracted ObjCARCContract from ObjCARCOpts into its own file.	2013-01-29 03:03:03 +00:00
DependencyAnalysis.cpp	Kill every call to @clang.arc.use in the ARC contract phase.	2013-03-22 21:38:36 +00:00
DependencyAnalysis.h	Extracted ObjCARCContract from ObjCARCOpts into its own file.	2013-01-29 03:03:03 +00:00
LLVMBuild.txt	Added missing dashes from header declaration comment.	2013-01-29 04:53:55 +00:00
Makefile
ObjCARC.cpp	This patch breaks up Wrap.h so that it does not have to include all of	2013-05-01 20:59:00 +00:00
ObjCARC.h	Add clang.arc.used to ModuleHasARC so ARC always runs if said call is present in a module.	2013-03-29 21:15:23 +00:00
ObjCARCAliasAnalysis.cpp	Sorted includes using utils/sort_includes.	2013-01-29 04:20:52 +00:00
ObjCARCAliasAnalysis.h	Added two missing headers from ObjCARCAliasAnalysis.h.	2013-01-29 04:09:24 +00:00
ObjCARCAPElim.cpp	Hopefully fix the Windows build failure introduced in r173769	2013-01-29 09:09:27 +00:00
ObjCARCContract.cpp	[objc-arc] Apply the RV optimization to retains next to calls in ObjCARCContract instead of ObjCARCOpts.	2013-04-29 06:53:53 +00:00
ObjCARCExpand.cpp	Sorted includes using utils/sort_includes.	2013-01-29 04:20:52 +00:00
ObjCARCOpts.cpp	[objc-arc-opts] In the presense of an alloca unconditionally remove RR pairs if and only if we are both KnownSafeBU/KnownSafeTD rather than just either or.	2013-05-13 23:49:42 +00:00
ObjCARCUtil.cpp	[ObjCARC Annotations] Added support for displaying the state of pointers at the bottom/top of BBs of the ARC dataflow analysis for both bottomup and topdown analyses.	2013-03-26 00:42:09 +00:00
ProvenanceAnalysis.cpp	Changed isStoredObjCPointer => IsStoredObjCPointer. No functionality change.	2013-02-12 23:35:08 +00:00
ProvenanceAnalysis.h	Fixed some whitespace/80+ violations. Also added a space after a namespace declaration.	2013-01-29 04:58:30 +00:00