From 7ab27d194ac9a303a5cb43f7012880d3d067fb99 Mon Sep 17 00:00:00 2001 From: Shoaib Meenai Date: Fri, 20 Apr 2018 22:11:03 +0000 Subject: [PATCH] [ObjCARC] Account for funclet token in storeStrong transform When creating a call to storeStrong in ObjCARCContract, ensure the call gets the correct funclet token, otherwise WinEHPrepare will turn the call (and all subsequent instructions) into unreachable. We already have logic to do this for the ARC autorelease elision marker; factor that out into a common function that's used for both. These are the only two places in this transform that create call instructions. Differential Revision: https://reviews.llvm.org/D45857 llvm-svn: 330487 --- lib/Transforms/ObjCARC/ObjCARCContract.cpp | 43 ++++++++++++------- .../ObjCARC/contract-storestrong-funclet.ll | 37 ++++++++++++++++ 2 files changed, 64 insertions(+), 16 deletions(-) create mode 100644 test/Transforms/ObjCARC/contract-storestrong-funclet.ll diff --git a/lib/Transforms/ObjCARC/ObjCARCContract.cpp b/lib/Transforms/ObjCARC/ObjCARCContract.cpp index 9898c131c1f..741f07ecb4a 100644 --- a/lib/Transforms/ObjCARC/ObjCARCContract.cpp +++ b/lib/Transforms/ObjCARC/ObjCARCContract.cpp @@ -91,8 +91,9 @@ namespace { SmallPtrSetImpl &DependingInstructions, SmallPtrSetImpl &Visited); - void tryToContractReleaseIntoStoreStrong(Instruction *Release, - inst_iterator &Iter); + void tryToContractReleaseIntoStoreStrong( + Instruction *Release, inst_iterator &Iter, + const DenseMap &BlockColors); void getAnalysisUsage(AnalysisUsage &AU) const override; bool doInitialization(Module &M) override; @@ -306,6 +307,24 @@ findRetainForStoreStrongContraction(Value *New, StoreInst *Store, return Retain; } +/// Create a call instruction with the correct funclet token. Should be used +/// instead of calling CallInst::Create directly. +static CallInst * +createCallInst(Value *Func, ArrayRef Args, const Twine &NameStr, + Instruction *InsertBefore, + const DenseMap &BlockColors) { + SmallVector OpBundles; + if (!BlockColors.empty()) { + const ColorVector &CV = BlockColors.find(InsertBefore->getParent())->second; + assert(CV.size() == 1 && "non-unique color for block!"); + Instruction *EHPad = CV.front()->getFirstNonPHI(); + if (EHPad->isEHPad()) + OpBundles.emplace_back("funclet", EHPad); + } + + return CallInst::Create(Func, Args, OpBundles, NameStr, InsertBefore); +} + /// Attempt to merge an objc_release with a store, load, and objc_retain to form /// an objc_storeStrong. An objc_storeStrong: /// @@ -333,8 +352,9 @@ findRetainForStoreStrongContraction(Value *New, StoreInst *Store, /// (4). /// 2. We need to make sure that any re-orderings of (1), (2), (3), (4) are /// safe. -void ObjCARCContract::tryToContractReleaseIntoStoreStrong(Instruction *Release, - inst_iterator &Iter) { +void ObjCARCContract::tryToContractReleaseIntoStoreStrong( + Instruction *Release, inst_iterator &Iter, + const DenseMap &BlockColors) { // See if we are releasing something that we just loaded. auto *Load = dyn_cast(GetArgRCIdentityRoot(Release)); if (!Load || !Load->isSimple()) @@ -386,7 +406,7 @@ void ObjCARCContract::tryToContractReleaseIntoStoreStrong(Instruction *Release, if (Args[1]->getType() != I8X) Args[1] = new BitCastInst(Args[1], I8X, "", Store); Constant *Decl = EP.get(ARCRuntimeEntryPointKind::StoreStrong); - CallInst *StoreStrong = CallInst::Create(Decl, Args, "", Store); + CallInst *StoreStrong = createCallInst(Decl, Args, "", Store, BlockColors); StoreStrong->setDoesNotThrow(); StoreStrong->setDebugLoc(Store->getDebugLoc()); @@ -462,16 +482,7 @@ bool ObjCARCContract::tryToPeepholeInstruction( RVInstMarker->getString(), /*Constraints=*/"", /*hasSideEffects=*/true); - SmallVector OpBundles; - if (!BlockColors.empty()) { - const ColorVector &CV = BlockColors.find(Inst->getParent())->second; - assert(CV.size() == 1 && "non-unique color for block!"); - Instruction *EHPad = CV.front()->getFirstNonPHI(); - if (EHPad->isEHPad()) - OpBundles.emplace_back("funclet", EHPad); - } - - CallInst::Create(IA, None, OpBundles, "", Inst); + createCallInst(IA, None, "", Inst, BlockColors); } decline_rv_optimization: return false; @@ -496,7 +507,7 @@ bool ObjCARCContract::tryToPeepholeInstruction( case ARCInstKind::Release: // Try to form an objc store strong from our release. If we fail, there is // nothing further to do below, so continue. - tryToContractReleaseIntoStoreStrong(Inst, Iter); + tryToContractReleaseIntoStoreStrong(Inst, Iter, BlockColors); return true; case ARCInstKind::User: // Be conservative if the function has any alloca instructions. diff --git a/test/Transforms/ObjCARC/contract-storestrong-funclet.ll b/test/Transforms/ObjCARC/contract-storestrong-funclet.ll new file mode 100644 index 00000000000..2155a36db41 --- /dev/null +++ b/test/Transforms/ObjCARC/contract-storestrong-funclet.ll @@ -0,0 +1,37 @@ +; RUN: opt -mtriple=i686-unknown-windows-msvc -objc-arc-contract -S -o - %s | FileCheck %s + +declare void @f() +declare i32 @__CxxFrameHandler3(...) +declare dllimport i8* @objc_retain(i8*) +declare dllimport i8* @objc_retainAutoreleasedReturnValue(i8*) +declare dllimport void @objc_release(i8*) + +@x = external global i8* + +define void @g(i8* %p) personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*) { + invoke void @f() to label %invoke.cont unwind label %ehcleanup + +invoke.cont: + %call = tail call i8* @objc_retain(i8* %p) nounwind + %tmp = load i8*, i8** @x, align 4 + store i8* %call, i8** @x, align 4 + tail call void @objc_release(i8* %tmp) nounwind + ret void + +ehcleanup: + %1 = cleanuppad within none [] + %call1 = tail call i8* @objc_retain(i8* %p) nounwind [ "funclet"(token %1) ] + %tmp1 = load i8*, i8** @x, align 4 + store i8* %call1, i8** @x, align 4 + tail call void @objc_release(i8* %tmp1) nounwind [ "funclet"(token %1) ] + cleanupret from %1 unwind to caller +} + +; CHECK-LABEL: invoke.cont: +; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %p) #0{{$}} +; CHECK: ret void + +; CHECK-LABEL: ehcleanup: +; CHECK: %1 = cleanuppad within none [] +; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %p) #0 [ "funclet"(token %1) ] +; CHECK: cleanupret from %1 unwind to caller