| //===- EHPersonalities.cpp - Compute EH-related information ---------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #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 GlobalValue *F = |
| Pers ? dyn_cast<GlobalValue>(Pers->stripPointerCasts()) : nullptr; |
| if (!F || !F->getValueType() || !F->getValueType()->isFunctionTy()) |
| return EHPersonality::Unknown; |
| return StringSwitch<EHPersonality>(F->getName()) |
| .Case("__gnat_eh_personality", EHPersonality::GNU_Ada) |
| .Case("__gxx_personality_v0", EHPersonality::GNU_CXX) |
| .Case("__gxx_personality_seh0", EHPersonality::GNU_CXX) |
| .Case("__gxx_personality_sj0", EHPersonality::GNU_CXX_SjLj) |
| .Case("__gcc_personality_v0", EHPersonality::GNU_C) |
| .Case("__gcc_personality_seh0", EHPersonality::GNU_C) |
| .Case("__gcc_personality_sj0", EHPersonality::GNU_C_SjLj) |
| .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_TableSEH) |
| .Case("__CxxFrameHandler3", EHPersonality::MSVC_CXX) |
| .Case("ProcessCLRException", EHPersonality::CoreCLR) |
| .Case("rust_eh_personality", EHPersonality::Rust) |
| .Case("__gxx_wasm_personality_v0", EHPersonality::Wasm_CXX) |
| .Case("__xlcxx_personality_v1", EHPersonality::XL_CXX) |
| .Default(EHPersonality::Unknown); |
| } |
| |
| StringRef llvm::getEHPersonalityName(EHPersonality Pers) { |
| switch (Pers) { |
| case EHPersonality::GNU_Ada: return "__gnat_eh_personality"; |
| case EHPersonality::GNU_CXX: return "__gxx_personality_v0"; |
| case EHPersonality::GNU_CXX_SjLj: return "__gxx_personality_sj0"; |
| case EHPersonality::GNU_C: return "__gcc_personality_v0"; |
| case EHPersonality::GNU_C_SjLj: return "__gcc_personality_sj0"; |
| case EHPersonality::GNU_ObjC: return "__objc_personality_v0"; |
| case EHPersonality::MSVC_X86SEH: return "_except_handler3"; |
| case EHPersonality::MSVC_TableSEH: |
| return "__C_specific_handler"; |
| case EHPersonality::MSVC_CXX: return "__CxxFrameHandler3"; |
| case EHPersonality::CoreCLR: return "ProcessCLRException"; |
| case EHPersonality::Rust: return "rust_eh_personality"; |
| case EHPersonality::Wasm_CXX: return "__gxx_wasm_personality_v0"; |
| case EHPersonality::XL_CXX: |
| return "__xlcxx_personality_v1"; |
| case EHPersonality::Unknown: llvm_unreachable("Unknown EHPersonality!"); |
| } |
| |
| llvm_unreachable("Invalid EHPersonality!"); |
| } |
| |
| EHPersonality llvm::getDefaultEHPersonality(const Triple &T) { |
| return EHPersonality::GNU_C; |
| } |
| |
| 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 (!is_contained(Colors, Color)) |
| Colors.push_back(Color); |
| else |
| continue; |
| |
| DEBUG_WITH_TYPE("winehprepare-coloring", |
| dbgs() << " Assigned color \'" << Color->getName() |
| << "\' to block \'" << Visiting->getName() |
| << "\'.\n"); |
| |
| BasicBlock *SuccColor = Color; |
| Instruction *Terminator = Visiting->getTerminator(); |
| if (auto *CatchRet = dyn_cast<CatchReturnInst>(Terminator)) { |
| Value *ParentPad = CatchRet->getCatchSwitchParentPad(); |
| if (isa<ConstantTokenNone>(ParentPad)) |
| SuccColor = EntryBlock; |
| else |
| SuccColor = cast<Instruction>(ParentPad)->getParent(); |
| } |
| |
| for (BasicBlock *Succ : successors(Visiting)) |
| Worklist.push_back({Succ, SuccColor}); |
| } |
| return BlockColors; |
| } |