diff options
Diffstat (limited to 'llvm/lib')
-rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/EHStreamer.cpp | 15 | ||||
-rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/EHStreamer.h | 17 | ||||
-rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp | 149 | ||||
-rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/Win64Exception.h | 4 | ||||
-rw-r--r-- | llvm/lib/CodeGen/MachineModuleInfo.cpp | 8 | ||||
-rw-r--r-- | llvm/lib/CodeGen/Passes.cpp | 2 | ||||
-rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 33 | ||||
-rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h | 2 | ||||
-rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 64 |
9 files changed, 276 insertions, 18 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.cpp b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.cpp index f112120c1ab..1bc86f6c222 100644 --- a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.cpp @@ -121,7 +121,8 @@ computeActionsTable(const SmallVectorImpl<const LandingPadInfo*> &LandingPads, for (unsigned J = NumShared, M = TypeIds.size(); J != M; ++J) { int TypeID = TypeIds[J]; assert(-1 - TypeID < (int)FilterOffsets.size() && "Unknown filter id!"); - int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID; + int ValueForTypeID = + isFilterEHSelector(TypeID) ? FilterOffsets[-1 - TypeID] : TypeID; unsigned SizeTypeID = getSLEB128Size(ValueForTypeID); int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0; @@ -269,14 +270,14 @@ computeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites, CallSiteEntry Site = { BeginLabel, LastLabel, - LandingPad->LandingPadLabel, + LandingPad, FirstActions[P.PadIndex] }; // Try to merge with the previous call-site. SJLJ doesn't do this if (PreviousIsInvoke && !IsSJLJ) { CallSiteEntry &Prev = CallSites.back(); - if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) { + if (Site.LPad == Prev.LPad && Site.Action == Prev.Action) { // Extend the range of the previous entry. Prev.EndLabel = Site.EndLabel; continue; @@ -576,15 +577,15 @@ void EHStreamer::emitExceptionTable() { // Offset of the landing pad, counted in 16-byte bundles relative to the // @LPStart address. - if (!S.PadLabel) { + if (!S.LPad) { if (VerboseAsm) Asm->OutStreamer.AddComment(" has no landing pad"); Asm->OutStreamer.EmitIntValue(0, 4/*size*/); } else { if (VerboseAsm) Asm->OutStreamer.AddComment(Twine(" jumps to ") + - S.PadLabel->getName()); - Asm->EmitLabelDifference(S.PadLabel, EHFuncBeginSym, 4); + S.LPad->LandingPadLabel->getName()); + Asm->EmitLabelDifference(S.LPad->LandingPadLabel, EHFuncBeginSym, 4); } // Offset of the first associated action record, relative to the start of @@ -681,7 +682,7 @@ void EHStreamer::emitTypeInfos(unsigned TTypeEncoding) { unsigned TypeID = *I; if (VerboseAsm) { --Entry; - if (TypeID != 0) + if (isFilterEHSelector(TypeID)) Asm->OutStreamer.AddComment("FilterInfo " + Twine(Entry)); } diff --git a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h index e93055ce865..9b316ff00e9 100644 --- a/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h +++ b/llvm/lib/CodeGen/AsmPrinter/EHStreamer.h @@ -23,6 +23,8 @@ class MachineModuleInfo; class MachineInstr; class MachineFunction; class AsmPrinter; +class MCSymbol; +class MCSymbolRefExpr; template <typename T> class SmallVectorImpl; @@ -60,11 +62,11 @@ protected: /// Structure describing an entry in the call-site table. struct CallSiteEntry { // The 'try-range' is BeginLabel .. EndLabel. - MCSymbol *BeginLabel; // zero indicates the start of the function. - MCSymbol *EndLabel; // zero indicates the end of the function. + MCSymbol *BeginLabel; // Null indicates the start of the function. + MCSymbol *EndLabel; // Null indicates the end of the function. - // The landing pad starts at PadLabel. - MCSymbol *PadLabel; // zero indicates that there is no landing pad. + // LPad contains the landing pad start labels. + const LandingPadInfo *LPad; // Null indicates that there is no landing pad. unsigned Action; }; @@ -112,6 +114,13 @@ protected: virtual void emitTypeInfos(unsigned TTypeEncoding); + // Helpers for for identifying what kind of clause an EH typeid or selector + // corresponds to. Negative selectors are for filter clauses, the zero + // selector is for cleanups, and positive selectors are for catch clauses. + static bool isFilterEHSelector(int Selector) { return Selector < 0; } + static bool isCleanupEHSelector(int Selector) { return Selector == 0; } + static bool isCatchEHSelector(int Selector) { return Selector > 0; } + public: EHStreamer(AsmPrinter *A); virtual ~EHStreamer(); diff --git a/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp b/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp index 0f0ad755835..2138cb9514f 100644 --- a/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp @@ -99,9 +99,156 @@ void Win64Exception::endFunction(const MachineFunction *) { if (shouldEmitPersonality) { Asm->OutStreamer.PushSection(); + + // Emit an UNWIND_INFO struct describing the prologue. Asm->OutStreamer.EmitWinEHHandlerData(); - emitExceptionTable(); + + // Emit either MSVC-compatible tables or the usual Itanium-style LSDA after + // the UNWIND_INFO struct. + if (Asm->MAI->getExceptionHandlingType() == ExceptionHandling::MSVC) { + const Function *Per = MMI->getPersonalities()[MMI->getPersonalityIndex()]; + if (Per->getName() == "__C_specific_handler") + emitCSpecificHandlerTable(); + else + report_fatal_error(Twine("unexpected personality function: ") + + Per->getName()); + } else { + emitExceptionTable(); + } + Asm->OutStreamer.PopSection(); } Asm->OutStreamer.EmitWinCFIEndProc(); } + +const MCSymbolRefExpr *Win64Exception::createImageRel32(const MCSymbol *Value) { + return MCSymbolRefExpr::Create(Value, MCSymbolRefExpr::VK_COFF_IMGREL32, + Asm->OutContext); +} + +/// Emit the language-specific data that __C_specific_handler expects. This +/// handler lives in the x64 Microsoft C runtime and allows catching or cleaning +/// up after faults with __try, __except, and __finally. The typeinfo values +/// are not really RTTI data, but pointers to filter functions that return an +/// integer (1, 0, or -1) indicating how to handle the exception. For __finally +/// blocks and other cleanups, the landing pad label is zero, and the filter +/// function is actually a cleanup handler with the same prototype. A catch-all +/// entry is modeled with a null filter function field and a non-zero landing +/// pad label. +/// +/// Possible filter function return values: +/// EXCEPTION_EXECUTE_HANDLER (1): +/// Jump to the landing pad label after cleanups. +/// EXCEPTION_CONTINUE_SEARCH (0): +/// Continue searching this table or continue unwinding. +/// EXCEPTION_CONTINUE_EXECUTION (-1): +/// Resume execution at the trapping PC. +/// +/// Inferred table structure: +/// struct Table { +/// int NumEntries; +/// struct Entry { +/// imagerel32 LabelStart; +/// imagerel32 LabelEnd; +/// imagerel32 FilterOrFinally; // Zero means catch-all. +/// imagerel32 LabelLPad; // Zero means __finally. +/// } Entries[NumEntries]; +/// }; +void Win64Exception::emitCSpecificHandlerTable() { + const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads(); + + // Simplifying assumptions for first implementation: + // - Cleanups are not implemented. + // - Filters are not implemented. + + // The Itanium LSDA table sorts similar landing pads together to simplify the + // actions table, but we don't need that. + SmallVector<const LandingPadInfo *, 64> LandingPads; + LandingPads.reserve(PadInfos.size()); + for (const auto &LP : PadInfos) + LandingPads.push_back(&LP); + + // Compute label ranges for call sites as we would for the Itanium LSDA, but + // use an all zero action table because we aren't using these actions. + SmallVector<unsigned, 64> FirstActions; + FirstActions.resize(LandingPads.size()); + SmallVector<CallSiteEntry, 64> CallSites; + computeCallSiteTable(CallSites, LandingPads, FirstActions); + + MCSymbol *EHFuncBeginSym = + Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber()); + MCSymbol *EHFuncEndSym = + Asm->GetTempSymbol("eh_func_end", Asm->getFunctionNumber()); + + // Emit the number of table entries. + unsigned NumEntries = 0; + for (const CallSiteEntry &CSE : CallSites) { + if (!CSE.LPad) + continue; // Ignore gaps. + for (int Selector : CSE.LPad->TypeIds) { + // Ignore C++ filter clauses in SEH. + // FIXME: Implement cleanup clauses. + if (isCatchEHSelector(Selector)) + ++NumEntries; + } + } + Asm->OutStreamer.EmitIntValue(NumEntries, 4); + + // Emit the four-label records for each call site entry. The table has to be + // sorted in layout order, and the call sites should already be sorted. + for (const CallSiteEntry &CSE : CallSites) { + // Ignore gaps. Unlike the Itanium model, unwinding through a frame without + // an EH table entry will propagate the exception rather than terminating + // the program. + if (!CSE.LPad) + continue; + const LandingPadInfo *LPad = CSE.LPad; + + // Compute the label range. We may reuse the function begin and end labels + // rather than forming new ones. + const MCExpr *Begin = + createImageRel32(CSE.BeginLabel ? CSE.BeginLabel : EHFuncBeginSym); + const MCExpr *End; + if (CSE.EndLabel) { + // The interval is half-open, so we have to add one to include the return + // address of the last invoke in the range. + End = MCBinaryExpr::CreateAdd(createImageRel32(CSE.EndLabel), + MCConstantExpr::Create(1, Asm->OutContext), + Asm->OutContext); + } else { + End = createImageRel32(EHFuncEndSym); + } + + // These aren't really type info globals, they are actually pointers to + // filter functions ordered by selector. The zero selector is used for + // cleanups, so slot zero corresponds to selector 1. + const std::vector<const GlobalValue *> &SelectorToFilter = MMI->getTypeInfos(); + + // Do a parallel iteration across typeids and clause labels, skipping filter + // clauses. + assert(LPad->TypeIds.size() == LPad->ClauseLabels.size()); + for (size_t I = 0, E = LPad->TypeIds.size(); I < E; ++I) { + // AddLandingPadInfo stores the clauses in reverse, but there is a FIXME + // to change that. + int Selector = LPad->TypeIds[E - I - 1]; + MCSymbol *ClauseLabel = LPad->ClauseLabels[I]; + + // Ignore C++ filter clauses in SEH. + // FIXME: Implement cleanup clauses. + if (!isCatchEHSelector(Selector)) + continue; + + Asm->OutStreamer.EmitValue(Begin, 4); + Asm->OutStreamer.EmitValue(End, 4); + if (isCatchEHSelector(Selector)) { + assert(unsigned(Selector - 1) < SelectorToFilter.size()); + const GlobalValue *TI = SelectorToFilter[Selector - 1]; + if (TI) // Emit the filter function pointer. + Asm->OutStreamer.EmitValue(createImageRel32(Asm->getSymbol(TI)), 4); + else // Otherwise, this is a "catch i8* null", or catch all. + Asm->OutStreamer.EmitIntValue(0, 4); + } + Asm->OutStreamer.EmitValue(createImageRel32(ClauseLabel), 4); + } + } +} diff --git a/llvm/lib/CodeGen/AsmPrinter/Win64Exception.h b/llvm/lib/CodeGen/AsmPrinter/Win64Exception.h index 538e1328157..b2d5d1bce56 100644 --- a/llvm/lib/CodeGen/AsmPrinter/Win64Exception.h +++ b/llvm/lib/CodeGen/AsmPrinter/Win64Exception.h @@ -29,6 +29,10 @@ class Win64Exception : public EHStreamer { /// Per-function flag to indicate if frame moves info should be emitted. bool shouldEmitMoves; + void emitCSpecificHandlerTable(); + + const MCSymbolRefExpr *createImageRel32(const MCSymbol *Value); + public: //===--------------------------------------------------------------------===// // Main entry points. diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp index baad411e2c5..32d511285eb 100644 --- a/llvm/lib/CodeGen/MachineModuleInfo.cpp +++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp @@ -452,6 +452,14 @@ void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) { LP.TypeIds.push_back(0); } +MCSymbol * +MachineModuleInfo::addClauseForLandingPad(MachineBasicBlock *LandingPad) { + MCSymbol *ClauseLabel = Context.CreateTempSymbol(); + LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); + LP.ClauseLabels.push_back(ClauseLabel); + return ClauseLabel; +} + /// TidyLandingPads - Remap landing pad labels and remove any deleted landing /// pads. void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) { diff --git a/llvm/lib/CodeGen/Passes.cpp b/llvm/lib/CodeGen/Passes.cpp index e53e874cb17..28e9f847a9d 100644 --- a/llvm/lib/CodeGen/Passes.cpp +++ b/llvm/lib/CodeGen/Passes.cpp @@ -449,9 +449,9 @@ void TargetPassConfig::addPassesToHandleExceptions() { case ExceptionHandling::DwarfCFI: case ExceptionHandling::ARM: case ExceptionHandling::ItaniumWinEH: + case ExceptionHandling::MSVC: // FIXME: Needs preparation. addPass(createDwarfEHPass(TM)); break; - case ExceptionHandling::MSVC: // FIXME: Add preparation. case ExceptionHandling::None: addPass(createLowerInvokePass()); diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 151bc724df6..86a63eea7c2 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -2071,10 +2071,14 @@ void SelectionDAGBuilder::visitLandingPad(const LandingPadInst &LP) { // Get the two live-in registers as SDValues. The physregs have already been // copied into virtual registers. SDValue Ops[2]; - Ops[0] = DAG.getZExtOrTrunc( - DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), - FuncInfo.ExceptionPointerVirtReg, TLI.getPointerTy()), - getCurSDLoc(), ValueVTs[0]); + if (FuncInfo.ExceptionPointerVirtReg) { + Ops[0] = DAG.getZExtOrTrunc( + DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), + FuncInfo.ExceptionPointerVirtReg, TLI.getPointerTy()), + getCurSDLoc(), ValueVTs[0]); + } else { + Ops[0] = DAG.getConstant(0, TLI.getPointerTy()); + } Ops[1] = DAG.getZExtOrTrunc( DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), FuncInfo.ExceptionSelectorVirtReg, TLI.getPointerTy()), @@ -2086,6 +2090,27 @@ void SelectionDAGBuilder::visitLandingPad(const LandingPadInst &LP) { setValue(&LP, Res); } +unsigned +SelectionDAGBuilder::visitLandingPadClauseBB(GlobalValue *ClauseGV, + MachineBasicBlock *LPadBB) { + SDValue Chain = getControlRoot(); + + // Get the typeid that we will dispatch on later. + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const TargetRegisterClass *RC = TLI.getRegClassFor(TLI.getPointerTy()); + unsigned VReg = FuncInfo.MF->getRegInfo().createVirtualRegister(RC); + unsigned TypeID = DAG.getMachineFunction().getMMI().getTypeIDFor(ClauseGV); + SDValue Sel = DAG.getConstant(TypeID, TLI.getPointerTy()); + Chain = DAG.getCopyToReg(Chain, getCurSDLoc(), VReg, Sel); + + // Branch to the main landing pad block. + MachineBasicBlock *ClauseMBB = FuncInfo.MBB; + ClauseMBB->addSuccessor(LPadBB); + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), MVT::Other, Chain, + DAG.getBasicBlock(LPadBB))); + return VReg; +} + /// handleSmallSwitchCaseRange - Emit a series of specific tests (suitable for /// small case ranges). bool SelectionDAGBuilder::handleSmallSwitchRange(CaseRec& CR, diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h index 8216a0223cd..c1f483186d9 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h @@ -713,6 +713,8 @@ public: void visitJumpTable(JumpTable &JT); void visitJumpTableHeader(JumpTable &JT, JumpTableHeader &JTH, MachineBasicBlock *SwitchBB); + unsigned visitLandingPadClauseBB(GlobalValue *ClauseGV, + MachineBasicBlock *LPadMBB); private: // These all get lowered before this pass. diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index 79109b7b8e6..a3f0fa47dd9 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -19,6 +19,7 @@ #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/Analysis/BranchProbabilityInfo.h" #include "llvm/Analysis/CFG.h" +#include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/FastISel.h" #include "llvm/CodeGen/FunctionLoweringInfo.h" #include "llvm/CodeGen/GCMetadata.h" @@ -40,6 +41,7 @@ #include "llvm/IR/Intrinsics.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Module.h" +#include "llvm/MC/MCAsmInfo.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" @@ -892,6 +894,8 @@ void SelectionDAGISel::DoInstructionSelection() { void SelectionDAGISel::PrepareEHLandingPad() { MachineBasicBlock *MBB = FuncInfo->MBB; + const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy()); + // Add a label to mark the beginning of the landing pad. Deletion of the // landing pad can thus be detected via the MachineModuleInfo. MCSymbol *Label = MF->getMMI().addLandingPad(MBB); @@ -903,8 +907,66 @@ void SelectionDAGISel::PrepareEHLandingPad() { BuildMI(*MBB, FuncInfo->InsertPt, SDB->getCurDebugLoc(), II) .addSym(Label); + if (TM.getMCAsmInfo()->getExceptionHandlingType() == + ExceptionHandling::MSVC) { + // Make virtual registers and a series of labels that fill in values for the + // clauses. + auto &RI = MF->getRegInfo(); + FuncInfo->ExceptionSelectorVirtReg = RI.createVirtualRegister(PtrRC); + + // Get all invoke BBs that will unwind into the clause BBs. + SmallVector<MachineBasicBlock *, 4> InvokeBBs(MBB->pred_begin(), + MBB->pred_end()); + + // Emit separate machine basic blocks with separate labels for each clause + // before the main landing pad block. + const BasicBlock *LLVMBB = MBB->getBasicBlock(); + const LandingPadInst *LPadInst = LLVMBB->getLandingPadInst(); + MachineInstrBuilder SelectorPHI = BuildMI( + *MBB, MBB->begin(), SDB->getCurDebugLoc(), TII->get(TargetOpcode::PHI), + FuncInfo->ExceptionSelectorVirtReg); + for (unsigned I = 0, E = LPadInst->getNumClauses(); I != E; ++I) { + MachineBasicBlock *ClauseBB = MF->CreateMachineBasicBlock(LLVMBB); + MF->insert(MBB, ClauseBB); + + // Add the edge from the invoke to the clause. + for (MachineBasicBlock *InvokeBB : InvokeBBs) + InvokeBB->addSuccessor(ClauseBB); + + // Mark the clause as a landing pad or MI passes will delete it. + ClauseBB->setIsLandingPad(); + + GlobalValue *ClauseGV = ExtractTypeInfo(LPadInst->getClause(I)); + + // Start the BB with a label. + MCSymbol *ClauseLabel = MF->getMMI().addClauseForLandingPad(MBB); + BuildMI(*ClauseBB, ClauseBB->begin(), SDB->getCurDebugLoc(), II) + .addSym(ClauseLabel); + + // Construct a simple BB that defines a register with the typeid constant. + FuncInfo->MBB = ClauseBB; + FuncInfo->InsertPt = ClauseBB->end(); + unsigned VReg = SDB->visitLandingPadClauseBB(ClauseGV, MBB); + CurDAG->setRoot(SDB->getRoot()); + SDB->clear(); + CodeGenAndEmitDAG(); + + // Add the typeid virtual register to the phi in the main landing pad. + SelectorPHI.addReg(VReg).addMBB(ClauseBB); + } + + // Remove the edge from the invoke to the lpad. + for (MachineBasicBlock *InvokeBB : InvokeBBs) + InvokeBB->removeSuccessor(MBB); + + // Restore FuncInfo back to its previous state and select the main landing + // pad block. + FuncInfo->MBB = MBB; + FuncInfo->InsertPt = MBB->end(); + return; + } + // Mark exception register as live in. - const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy()); if (unsigned Reg = TLI->getExceptionPointerRegister()) FuncInfo->ExceptionPointerVirtReg = MBB->addLiveIn(Reg, PtrRC); |