| //===-- UnreachableBlockElim.h - Remove unreachable blocks for codegen --===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This pass is an extremely simple version of the SimplifyCFG pass. Its sole |
| // job is to delete LLVM basic blocks that are not reachable from the entry |
| // node. To do this, it performs a simple depth first traversal of the CFG, |
| // then deletes any unvisited nodes. |
| // |
| // Note that this pass is really a hack. In particular, the instruction |
| // selectors for various targets should just not generate code for unreachable |
| // blocks. Until LLVM has a more systematic way of defining instruction |
| // selectors, however, we cannot really expect them to handle additional |
| // complexity. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H |
| #define LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H |
| |
| #include "llvm/IR/PassManager.h" |
| |
| namespace llvm { |
| |
| class UnreachableBlockElimPass |
| : public PassInfoMixin<UnreachableBlockElimPass> { |
| public: |
| PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); |
| }; |
| } // end namespace llvm |
| |
| #endif // LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H |
