diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp | 149 |
1 files changed, 1 insertions, 148 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp index 2138cb9..0f0ad75 100644 --- a/contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp @@ -99,156 +99,9 @@ void Win64Exception::endFunction(const MachineFunction *) { if (shouldEmitPersonality) { Asm->OutStreamer.PushSection(); - - // Emit an UNWIND_INFO struct describing the prologue. Asm->OutStreamer.EmitWinEHHandlerData(); - - // 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(); - } - + 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); - } - } -} |