| //===--- llvm/CodeGen/WasmEHFuncInfo.h --------------------------*- C++ -*-===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Data structures for Wasm exception handling schemes. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CODEGEN_WASMEHFUNCINFO_H |
| #define LLVM_CODEGEN_WASMEHFUNCINFO_H |
| |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/PointerUnion.h" |
| #include "llvm/ADT/SmallPtrSet.h" |
| |
| namespace llvm { |
| |
| class BasicBlock; |
| class Function; |
| class MachineBasicBlock; |
| |
| namespace WebAssembly { |
| enum Tag { CPP_EXCEPTION = 0, C_LONGJMP = 1 }; |
| } |
| |
| using BBOrMBB = PointerUnion<const BasicBlock *, MachineBasicBlock *>; |
| |
| struct WasmEHFuncInfo { |
| // When there is an entry <A, B>, if an exception is not caught by A, it |
| // should next unwind to the EH pad B. |
| DenseMap<BBOrMBB, BBOrMBB> SrcToUnwindDest; |
| DenseMap<BBOrMBB, SmallPtrSet<BBOrMBB, 4>> UnwindDestToSrcs; // reverse map |
| |
| // Helper functions |
| const BasicBlock *getUnwindDest(const BasicBlock *BB) const { |
| assert(hasUnwindDest(BB)); |
| return SrcToUnwindDest.lookup(BB).get<const BasicBlock *>(); |
| } |
| SmallPtrSet<const BasicBlock *, 4> getUnwindSrcs(const BasicBlock *BB) const { |
| assert(hasUnwindSrcs(BB)); |
| const auto &Set = UnwindDestToSrcs.lookup(BB); |
| SmallPtrSet<const BasicBlock *, 4> Ret; |
| for (const auto P : Set) |
| Ret.insert(P.get<const BasicBlock *>()); |
| return Ret; |
| } |
| void setUnwindDest(const BasicBlock *BB, const BasicBlock *Dest) { |
| SrcToUnwindDest[BB] = Dest; |
| if (!UnwindDestToSrcs.count(Dest)) |
| UnwindDestToSrcs[Dest] = SmallPtrSet<BBOrMBB, 4>(); |
| UnwindDestToSrcs[Dest].insert(BB); |
| } |
| bool hasUnwindDest(const BasicBlock *BB) const { |
| return SrcToUnwindDest.count(BB); |
| } |
| bool hasUnwindSrcs(const BasicBlock *BB) const { |
| return UnwindDestToSrcs.count(BB); |
| } |
| |
| MachineBasicBlock *getUnwindDest(MachineBasicBlock *MBB) const { |
| assert(hasUnwindDest(MBB)); |
| return SrcToUnwindDest.lookup(MBB).get<MachineBasicBlock *>(); |
| } |
| SmallPtrSet<MachineBasicBlock *, 4> |
| getUnwindSrcs(MachineBasicBlock *MBB) const { |
| assert(hasUnwindSrcs(MBB)); |
| const auto &Set = UnwindDestToSrcs.lookup(MBB); |
| SmallPtrSet<MachineBasicBlock *, 4> Ret; |
| for (const auto P : Set) |
| Ret.insert(P.get<MachineBasicBlock *>()); |
| return Ret; |
| } |
| void setUnwindDest(MachineBasicBlock *MBB, MachineBasicBlock *Dest) { |
| SrcToUnwindDest[MBB] = Dest; |
| if (!UnwindDestToSrcs.count(Dest)) |
| UnwindDestToSrcs[Dest] = SmallPtrSet<BBOrMBB, 4>(); |
| UnwindDestToSrcs[Dest].insert(MBB); |
| } |
| bool hasUnwindDest(MachineBasicBlock *MBB) const { |
| return SrcToUnwindDest.count(MBB); |
| } |
| bool hasUnwindSrcs(MachineBasicBlock *MBB) const { |
| return UnwindDestToSrcs.count(MBB); |
| } |
| }; |
| |
| // Analyze the IR in the given function to build WasmEHFuncInfo. |
| void calculateWasmEHInfo(const Function *F, WasmEHFuncInfo &EHInfo); |
| |
| } // namespace llvm |
| |
| #endif // LLVM_CODEGEN_WASMEHFUNCINFO_H |