From: Michael Gottesman Date: Tue, 5 Nov 2013 16:02:40 +0000 (+0000) Subject: [objc-arc] Convert the one directional retain/release relation assert to a conditiona... X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f23af8bfd8609b9594947876209c3f0de070ea4f;p=oota-llvm.git [objc-arc] Convert the one directional retain/release relation assert to a conditional check + fail. Due to the previously added overflow checks, we can have a retain/release relation that is one directional. This occurs specifically when we run into an additive overflow causing us to drop state in only one direction. If that occurs, we should bail and not optimize that retain/release instead of asserting. Apologies for the size of the testcase. It is necessary to cause the additive cfg overflow to trigger. rdar://15377890 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194083 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/Transforms/ObjCARC/ObjCARCOpts.cpp b/lib/Transforms/ObjCARC/ObjCARCOpts.cpp index b419a7ecc8a..1cc665b2e02 100644 --- a/lib/Transforms/ObjCARC/ObjCARCOpts.cpp +++ b/lib/Transforms/ObjCARC/ObjCARCOpts.cpp @@ -2405,7 +2405,15 @@ ObjCARCOpt::ConnectTDBUTraversals(DenseMap if (Jt == Releases.end()) return false; const RRInfo &NewRetainReleaseRRI = Jt->second; - assert(NewRetainReleaseRRI.Calls.count(NewRetain)); + + // If the release does not have a reference to the retain as well, + // something happened which is unaccounted for. Do not do anything. + // + // This can happen if we catch an additive overflow during path count + // merging. + if (!NewRetainReleaseRRI.Calls.count(NewRetain)) + return false; + if (ReleasesToMove.Calls.insert(NewRetainRelease)) { // If we overflow when we compute the path count, don't remove/move @@ -2481,9 +2489,16 @@ ObjCARCOpt::ConnectTDBUTraversals(DenseMap if (Jt == Retains.end()) return false; const RRInfo &NewReleaseRetainRRI = Jt->second; - assert(NewReleaseRetainRRI.Calls.count(NewRelease)); - if (RetainsToMove.Calls.insert(NewReleaseRetain)) { + // If the retain does not have a reference to the release as well, + // something happened which is unaccounted for. Do not do anything. + // + // This can happen if we catch an additive overflow during path count + // merging. + if (!NewReleaseRetainRRI.Calls.count(NewRelease)) + return false; + + if (RetainsToMove.Calls.insert(NewReleaseRetain)) { // If we overflow when we compute the path count, don't remove/move // anything. const BBState &NRRBBState = BBStates[NewReleaseRetain->getParent()]; diff --git a/test/Transforms/ObjCARC/path-overflow.ll b/test/Transforms/ObjCARC/path-overflow.ll index e62a70da20a..3c14353947a 100644 --- a/test/Transforms/ObjCARC/path-overflow.ll +++ b/test/Transforms/ObjCARC/path-overflow.ll @@ -2,6 +2,7 @@ ; rdar://12277446 ; rdar://12480535 ; rdar://14590914 +; rdar://15377890 ; The total number of paths grows exponentially with the number of branches, and a ; computation of this number can overflow any reasonable fixed-sized @@ -15,6 +16,7 @@ target triple = "thumbv7-apple-ios5.0.0" %struct.CGPoint = type { float, float } @_unnamed_cfstring = external constant %struct.NSConstantString, section "__DATA,__cfstring" +@_unnamed_cfstring_2 = external constant %struct.NSConstantString, section "__DATA,__cfstring" declare i8* @objc_retain(i8*) nonlazybind declare i8* @objc_retainAutoreleasedReturnValue(i8*) nonlazybind @@ -24,6 +26,7 @@ declare i8* @objc_msgSend(i8*, i8*, ...) nonlazybind declare void @NSLog(i8*, ...) declare void @objc_msgSend_stret(i8*, i8*, ...) declare i32 @__gxx_personality_sj0(...) +declare i32 @__objc_personality_v0(...) define hidden void @test1() { @@ -1914,4 +1917,277 @@ eh.resume: ; preds = %lpad580, %ehcleanup resume { i8*, i32 } undef } +@"OBJC_EHTYPE_$_NSException" = external global i8 + +define void @test4() { +entry: + br i1 undef, label %if.end13, label %if.then10 + +if.then10: ; preds = %entry + br label %if.end13 + +if.end13: ; preds = %if.then10, %entry + %0 = call i8* bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to i8* (i8*, i8*, i8*, i64, i8*, i8)*)(i8* undef, i8* undef, i8* bitcast (%struct.NSConstantString* @_unnamed_cfstring to i8*), i64 2, i8* bitcast (%struct.NSConstantString* @_unnamed_cfstring_2 to i8*), i8 signext 0), !clang.arc.no_objc_arc_exceptions !0 + br i1 undef, label %if.then17, label %if.end18 + +if.then17: ; preds = %if.end13 + br label %if.end18 + +if.end18: ; preds = %if.then17, %if.end13 + br i1 undef, label %if.then64, label %if.end73 + +if.then64: ; preds = %if.end18 + br i1 undef, label %cond.end71, label %cond.true68 + +cond.true68: ; preds = %if.then64 + br label %cond.end71 + +cond.end71: ; preds = %cond.true68, %if.then64 + br i1 undef, label %cleanup.action, label %cleanup.done + +cleanup.action: ; preds = %cond.end71 + br label %cleanup.done + +cleanup.done: ; preds = %cleanup.action, %cond.end71 + br label %if.end73 + +if.end73: ; preds = %cleanup.done, %if.end18 + br i1 undef, label %forcoll.empty, label %forcoll.loopinit + +forcoll.loopinit: ; preds = %if.end73 + br label %forcoll.loopbody.outer + +forcoll.loopbody.outer: ; preds = %forcoll.refetch, %forcoll.loopinit + br label %forcoll.loopbody + +forcoll.loopbody: ; preds = %forcoll.notmutated, %forcoll.loopbody.outer + br i1 undef, label %forcoll.notmutated, label %forcoll.mutated + +forcoll.mutated: ; preds = %forcoll.loopbody + br label %forcoll.notmutated + +forcoll.notmutated: ; preds = %forcoll.mutated, %forcoll.loopbody + br i1 undef, label %forcoll.loopbody, label %forcoll.refetch + +forcoll.refetch: ; preds = %forcoll.notmutated + br i1 undef, label %forcoll.empty, label %forcoll.loopbody.outer + +forcoll.empty: ; preds = %forcoll.refetch, %if.end73 + br i1 undef, label %if.end85, label %if.then82 + +if.then82: ; preds = %forcoll.empty + br label %if.end85 + +if.end85: ; preds = %if.then82, %forcoll.empty + br i1 undef, label %if.then87, label %if.end102 + +if.then87: ; preds = %if.end85 + br i1 undef, label %if.end94, label %if.then91 + +if.then91: ; preds = %if.then87 + br label %if.end94 + +if.end94: ; preds = %if.then91, %if.then87 + br i1 undef, label %if.end101, label %if.then98 + +if.then98: ; preds = %if.end94 + br label %if.end101 + +if.end101: ; preds = %if.then98, %if.end94 + br label %if.end102 + +if.end102: ; preds = %if.end101, %if.end85 + br i1 undef, label %do.body113, label %if.then107 + +if.then107: ; preds = %if.end102 + br label %do.body113 + +do.body113: ; preds = %if.then107, %if.end102 + br i1 undef, label %if.then116, label %if.end117 + +if.then116: ; preds = %do.body113 + br label %if.end117 + +if.end117: ; preds = %if.then116, %do.body113 + br i1 undef, label %if.then125, label %if.end126 + +if.then125: ; preds = %if.end117 + br label %if.end126 + +if.end126: ; preds = %if.then125, %if.end117 + br i1 undef, label %do.end166, label %cond.true132 + +cond.true132: ; preds = %if.end126 + br i1 undef, label %do.body148, label %cond.true151 + +do.body148: ; preds = %cond.true132 + br i1 undef, label %do.end166, label %cond.true151 + +cond.true151: ; preds = %do.body148, %cond.true132 + br i1 undef, label %if.then162, label %do.end166 + +if.then162: ; preds = %cond.true151 + br label %do.end166 + +do.end166: ; preds = %if.then162, %cond.true151, %do.body148, %if.end126 + br i1 undef, label %if.then304, label %if.then170 + +if.then170: ; preds = %do.end166 + br i1 undef, label %do.end193, label %cond.true179 + +cond.true179: ; preds = %if.then170 + br i1 undef, label %if.then190, label %do.end193 + +if.then190: ; preds = %cond.true179 + br label %do.end193 + +do.end193: ; preds = %if.then190, %cond.true179, %if.then170 + br i1 undef, label %do.body200, label %do.body283 + +do.body200: ; preds = %do.end193 + br i1 undef, label %do.end254, label %cond.true203 + +cond.true203: ; preds = %do.body200 + br i1 undef, label %do.body218, label %cond.true221 + +do.body218: ; preds = %cond.true203 + br i1 undef, label %do.end254, label %cond.true221 + +cond.true221: ; preds = %do.body218, %cond.true203 + br i1 undef, label %if.then232, label %do.body236 + +if.then232: ; preds = %cond.true221 + br label %do.body236 + +do.body236: ; preds = %if.then232, %cond.true221 + br i1 undef, label %do.end254, label %cond.true239 + +cond.true239: ; preds = %do.body236 + br i1 undef, label %if.then250, label %do.end254 + +if.then250: ; preds = %cond.true239 + br label %do.end254 + +do.end254: ; preds = %if.then250, %cond.true239, %do.body236, %do.body218, %do.body200 + br i1 undef, label %do.end277, label %cond.true263 + +cond.true263: ; preds = %do.end254 + br i1 undef, label %if.then274, label %do.end277 + +if.then274: ; preds = %cond.true263 + unreachable + +do.end277: ; preds = %cond.true263, %do.end254 + br i1 undef, label %if.then280, label %do.body283 + +if.then280: ; preds = %do.end277 + br label %do.body283 + +do.body283: ; preds = %if.then280, %do.end277, %do.end193 + br i1 undef, label %if.end301, label %cond.true286 + +cond.true286: ; preds = %do.body283 + br i1 undef, label %if.then297, label %if.end301 + +if.then297: ; preds = %cond.true286 + br label %if.end301 + +if.end301: ; preds = %if.then297, %cond.true286, %do.body283 + br i1 undef, label %if.then304, label %do.body351 + +if.then304: ; preds = %if.end301, %do.end166 + br i1 undef, label %do.body309.lr.ph, label %do.body351 + +do.body309.lr.ph: ; preds = %if.then304 + br label %do.body309 + +do.body309: ; preds = %for.cond.backedge, %do.body309.lr.ph + br i1 undef, label %do.end328, label %cond.true312 + +cond.true312: ; preds = %do.body309 + br i1 undef, label %if.then323, label %do.end328 + +if.then323: ; preds = %cond.true312 + br label %do.end328 + +do.end328: ; preds = %if.then323, %cond.true312, %do.body309 + br i1 undef, label %for.cond.backedge, label %cond.true335 + +for.cond.backedge: ; preds = %if.then346, %cond.true335, %do.end328 + br i1 undef, label %do.body309, label %do.body351 + +cond.true335: ; preds = %do.end328 + br i1 undef, label %if.then346, label %for.cond.backedge + +if.then346: ; preds = %cond.true335 + br label %for.cond.backedge + +do.body351: ; preds = %for.cond.backedge, %if.then304, %if.end301 + br i1 undef, label %if.then354, label %if.end355 + +if.then354: ; preds = %do.body351 + br label %if.end355 + +if.end355: ; preds = %if.then354, %do.body351 + br i1 undef, label %if.else, label %if.then364 + +if.then364: ; preds = %if.end355 + br label %do.body366 + +if.else: ; preds = %if.end355 + br label %do.body366 + +do.body366: ; preds = %if.else, %if.then364 + br i1 undef, label %if.then369, label %if.end377.critedge + +if.then369: ; preds = %do.body366 + br label %if.end377 + +if.end377.critedge: ; preds = %do.body366 + br label %if.end377 + +if.end377: ; preds = %if.end377.critedge, %if.then369 + br i1 undef, label %if.then383, label %if.end392.critedge + +if.then383: ; preds = %if.end377 + br label %if.end392 + +if.end392.critedge: ; preds = %if.end377 + br label %if.end392 + +if.end392: ; preds = %if.end392.critedge, %if.then383 + br i1 undef, label %if.then398, label %if.end399 + +if.then398: ; preds = %if.end392 + br label %if.end399 + +if.end399: ; preds = %if.then398, %if.end392 + invoke void bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to void (i8*, i8*)*)(i8* undef, i8* undef) + to label %eh.cont unwind label %lpad, !clang.arc.no_objc_arc_exceptions !0 + +eh.cont: ; preds = %if.end399 + br i1 undef, label %if.then430, label %if.end439.critedge + +if.then430: ; preds = %eh.cont + %1 = call i8* @objc_retain(i8* %0) + br label %if.end439 + +lpad: ; preds = %if.end399 + %2 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__objc_personality_v0 to i8*) + catch i8* @"OBJC_EHTYPE_$_NSException" + unreachable + +if.end439.critedge: ; preds = %eh.cont + %3 = call i8* @objc_retain(i8* %0) + br label %if.end439 + +if.end439: ; preds = %if.end439.critedge, %if.then430 + call void @objc_release(i8* %0), !clang.imprecise_release !0 + unreachable + +return: ; No predecessors! + ret void +} + + !0 = metadata !{}