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+// Copyright (c) 2022 The Khronos Group Inc.
+// Copyright (c) 2022 LunarG 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 SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_
+#define SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_
+
+#include <unordered_map>
+
+#include "source/opt/ir_context.h"
+#include "source/opt/module.h"
+#include "source/opt/pass.h"
+
+namespace spvtools {
+namespace opt {
+
+// See optimizer.hpp for documentation.
+class EliminateDeadInputComponentsPass : public Pass {
+ public:
+  explicit EliminateDeadInputComponentsPass() {}
+
+  const char* name() const override { return "reduce-load-size"; }
+  Status Process() override;
+
+  // Return the mask of preserved Analyses.
+  IRContext::Analysis GetPreservedAnalyses() override {
+    return IRContext::kAnalysisDefUse |
+           IRContext::kAnalysisInstrToBlockMapping |
+           IRContext::kAnalysisCombinators | IRContext::kAnalysisCFG |
+           IRContext::kAnalysisDominatorAnalysis |
+           IRContext::kAnalysisLoopAnalysis | IRContext::kAnalysisNameMap |
+           IRContext::kAnalysisConstants | IRContext::kAnalysisTypes;
+  }
+
+ private:
+  // Find the max constant used to index the variable declared by |var|
+  // through OpAccessChain or OpInBoundsAccessChain. If any non-constant
+  // indices or non-Op*AccessChain use of |var|, return |original_max|.
+  unsigned FindMaxIndex(Instruction& var, unsigned original_max);
+
+  // Change the length of the array |inst| to |length|
+  void ChangeArrayLength(Instruction& inst, unsigned length);
+};
+
+}  // namespace opt
+}  // namespace spvtools
+
+#endif  // SOURCE_OPT_ELIMINATE_DEAD_INPUT_COMPONENTS_H_