| // Copyright (c) 2017 Google Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef LIBSPIRV_OPT_PRIVATE_TO_LOCAL_PASS_H_ |
| #define LIBSPIRV_OPT_PRIVATE_TO_LOCAL_PASS_H_ |
| |
| #include "ir_context.h" |
| #include "pass.h" |
| |
| namespace spvtools { |
| namespace opt { |
| |
| // This pass implements total redundancy elimination. This is the same as |
| // local redundancy elimination except it looks across basic block boundaries. |
| // An instruction, inst, is totally redundant if there is another instruction |
| // that dominates inst, and also computes the same value. |
| class PrivateToLocalPass : public Pass { |
| public: |
| const char* name() const override { return "private-to-local"; } |
| Status Process(ir::IRContext*) override; |
| ir::IRContext::Analysis GetPreservedAnalyses() override { |
| return ir::IRContext::kAnalysisDefUse | |
| ir::IRContext::kAnalysisDecorations | |
| ir::IRContext::kAnalysisCombinators | ir::IRContext::kAnalysisCFG | |
| ir::IRContext::kAnalysisDominatorAnalysis | |
| ir::IRContext::kAnalysisNameMap; |
| } |
| |
| private: |
| // Moves |variable| from the private storage class to the function storage |
| // class of |function|. |
| void MoveVariable(ir::Instruction* variable, ir::Function* function); |
| |
| // |inst| is an instruction declaring a varible. If that variable is |
| // referenced in a single function and all of uses are valid as defined by |
| // |IsValidUse|, then that function is returned. Otherwise, the return |
| // value is |nullptr|. |
| ir::Function* FindLocalFunction(const ir::Instruction& inst) const; |
| |
| // Returns true is |inst| is a valid use of a pointer. In this case, a |
| // valid use is one where the transformation is able to rewrite the type to |
| // match a change in storage class of the original variable. |
| bool IsValidUse(const ir::Instruction* inst) const; |
| |
| // Given the result id of a pointer type, |old_type_id|, this function |
| // returns the id of a the same pointer type except the storage class has |
| // been changed to function. If the type does not already exist, it will be |
| // created. |
| uint32_t GetNewType(uint32_t old_type_id); |
| |
| // Updates |inst|, and any instruction dependent on |inst|, to reflect the |
| // change of the base pointer now pointing to the function storage class. |
| void UpdateUse(ir::Instruction* inst); |
| void UpdateUses(uint32_t id); |
| }; |
| |
| } // namespace opt |
| } // namespace spvtools |
| |
| #endif // LIBSPIRV_OPT_PRIVATE_TO_LOCAL_PASS_H_ |