| //===- AMDGPUUnifyDivergentExitNodes.h ------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This is a variant of the UnifyFunctionExitNodes pass. Rather than ensuring |
| // there is at most one ret and one unreachable instruction, it ensures there is |
| // at most one divergent exiting block. |
| // |
| // StructurizeCFG can't deal with multi-exit regions formed by branches to |
| // multiple return nodes. It is not desirable to structurize regions with |
| // uniform branches, so unifying those to the same return block as divergent |
| // branches inhibits use of scalar branching. It still can't deal with the case |
| // where one branch goes to return, and one unreachable. Replace unreachable in |
| // this case with a return. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "AMDGPU.h" |
| |
| namespace llvm { |
| class AMDGPUUnifyDivergentExitNodesPass |
| : public PassInfoMixin<AMDGPUUnifyDivergentExitNodesPass> { |
| public: |
| PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); |
| }; |
| |
| } // end namespace llvm |
