| //===- EHPersonalities.cpp - Compute EH-related information ---------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Analysis/EHPersonalities.h" |
| #include "llvm/ADT/StringSwitch.h" |
| #include "llvm/IR/CFG.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/Instructions.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace llvm; |
| |
| /// See if the given exception handling personality function is one that we |
| /// understand. If so, return a description of it; otherwise return Unknown. |
| EHPersonality llvm::classifyEHPersonality(const Value *Pers) { |
| const Function *F = |
| Pers ? dyn_cast<Function>(Pers->stripPointerCasts()) : nullptr; |
| if (!F) |
| return EHPersonality::Unknown; |
| return StringSwitch<EHPersonality>(F->getName()) |
| .Case("__gnat_eh_personality", EHPersonality::GNU_Ada) |
| .Case("__gxx_personality_v0", EHPersonality::GNU_CXX) |
| .Case("__gcc_personality_v0", EHPersonality::GNU_C) |
| .Case("__objc_personality_v0", EHPersonality::GNU_ObjC) |
| .Case("_except_handler3", EHPersonality::MSVC_X86SEH) |
| .Case("_except_handler4", EHPersonality::MSVC_X86SEH) |
| .Case("__C_specific_handler", EHPersonality::MSVC_Win64SEH) |
| .Case("__CxxFrameHandler3", EHPersonality::MSVC_CXX) |
| .Case("ProcessCLRException", EHPersonality::CoreCLR) |
| .Default(EHPersonality::Unknown); |
| } |
| |
| bool llvm::canSimplifyInvokeNoUnwind(const Function *F) { |
| EHPersonality Personality = classifyEHPersonality(F->getPersonalityFn()); |
| // We can't simplify any invokes to nounwind functions if the personality |
| // function wants to catch asynch exceptions. The nounwind attribute only |
| // implies that the function does not throw synchronous exceptions. |
| return !isAsynchronousEHPersonality(Personality); |
| } |
| |
| DenseMap<BasicBlock *, ColorVector> llvm::colorEHFunclets(Function &F) { |
| SmallVector<std::pair<BasicBlock *, BasicBlock *>, 16> Worklist; |
| BasicBlock *EntryBlock = &F.getEntryBlock(); |
| DenseMap<BasicBlock *, ColorVector> BlockColors; |
| |
| // Build up the color map, which maps each block to its set of 'colors'. |
| // For any block B the "colors" of B are the set of funclets F (possibly |
| // including a root "funclet" representing the main function) such that |
| // F will need to directly contain B or a copy of B (where the term "directly |
| // contain" is used to distinguish from being "transitively contained" in |
| // a nested funclet). |
| // |
| // Note: Despite not being a funclet in the truest sense, a catchswitch is |
| // considered to belong to its own funclet for the purposes of coloring. |
| |
| DEBUG_WITH_TYPE("winehprepare-coloring", dbgs() << "\nColoring funclets for " |
| << F.getName() << "\n"); |
| |
| Worklist.push_back({EntryBlock, EntryBlock}); |
| |
| while (!Worklist.empty()) { |
| BasicBlock *Visiting; |
| BasicBlock *Color; |
| std::tie(Visiting, Color) = Worklist.pop_back_val(); |
| DEBUG_WITH_TYPE("winehprepare-coloring", |
| dbgs() << "Visiting " << Visiting->getName() << ", " |
| << Color->getName() << "\n"); |
| Instruction *VisitingHead = Visiting->getFirstNonPHI(); |
| if (VisitingHead->isEHPad()) { |
| // Mark this funclet head as a member of itself. |
| Color = Visiting; |
| } |
| // Note that this is a member of the given color. |
| ColorVector &Colors = BlockColors[Visiting]; |
| if (std::find(Colors.begin(), Colors.end(), Color) == Colors.end()) |
| Colors.push_back(Color); |
| else |
| continue; |
| |
| DEBUG_WITH_TYPE("winehprepare-coloring", |
| dbgs() << " Assigned color \'" << Color->getName() |
| << "\' to block \'" << Visiting->getName() |
| << "\'.\n"); |
| |
| BasicBlock *SuccColor = Color; |
| TerminatorInst *Terminator = Visiting->getTerminator(); |
| if (auto *CatchRet = dyn_cast<CatchReturnInst>(Terminator)) { |
| Value *ParentPad = CatchRet->getParentPad(); |
| if (isa<ConstantTokenNone>(ParentPad)) |
| SuccColor = EntryBlock; |
| else |
| SuccColor = cast<Instruction>(ParentPad)->getParent(); |
| } |
| |
| for (BasicBlock *Succ : successors(Visiting)) |
| Worklist.push_back({Succ, SuccColor}); |
| } |
| return BlockColors; |
| } |