SPIRV-Tools/source/opt/def_use_manager.h
Lei Zhang 114af21994 Add MessageConsumer to PassManager, Pass, and analysis interfaces.
Also convert some uses of assert() in optimization code to use
SPIRV_ASSERT(), SPIRV_UNIMPLEMENTED(), or SPIRV_UNREACHABLE()
accordingly.
2016-09-16 13:14:57 -04:00

131 lines
5.4 KiB
C++

// Copyright (c) 2016 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_DEF_USE_MANAGER_H_
#define LIBSPIRV_OPT_DEF_USE_MANAGER_H_
#include <list>
#include <unordered_map>
#include <utility>
#include <vector>
#include "instruction.h"
#include "message.h"
#include "module.h"
namespace spvtools {
namespace opt {
namespace analysis {
// Class for representing a use of id. Note that:
// * Result type id is a use.
// * Ids referenced in OpSectionMerge & OpLoopMerge are considered as use.
// * Ids referenced in OpPhi's in operands are considered as use.
struct Use {
ir::Instruction* inst; // Instruction using the id.
uint32_t operand_index; // logical operand index of the id use. This can be
// the index of result type id.
};
using UseList = std::list<Use>;
// A class for analyzing and managing defs and uses in an ir::Module.
class DefUseManager {
public:
using IdToDefMap = std::unordered_map<uint32_t, ir::Instruction*>;
using IdToUsesMap = std::unordered_map<uint32_t, UseList>;
// Constructs a def-use manager from the given |module|. All internal messages
// will be communicated to the outside via the given message |consumer|. This
// instance only keeps a reference to the |consumer|, so the |consumer| should
// outlive this instance.
DefUseManager(const MessageConsumer& consumer, ir::Module* module)
: consumer_(consumer) {
AnalyzeDefUse(module);
}
DefUseManager(const DefUseManager&) = delete;
DefUseManager(DefUseManager&&) = delete;
DefUseManager& operator=(const DefUseManager&) = delete;
DefUseManager& operator=(DefUseManager&&) = delete;
// Analyzes the defs and uses in the given |inst|.
void AnalyzeInstDefUse(ir::Instruction* inst);
// Returns the def instruction for the given |id|. If there is no instruction
// defining |id|, returns nullptr.
ir::Instruction* GetDef(uint32_t id);
// Returns the use instructions for the given |id|. If there is no uses of
// |id|, returns nullptr.
UseList* GetUses(uint32_t id);
const UseList* GetUses(uint32_t id) const;
// Returns the annotation instrunctions which are a direct use of the given
// |id|. This means when the decorations are applied through decoration
// group(s), this function will just return the OpGroupDecorate
// instrcution(s) which refer to the given id as an operand. The OpDecorate
// instructions which decorate the decoration group will not be returned.
std::vector<ir::Instruction*> GetAnnotations(uint32_t id) const;
// Returns the map from ids to their def instructions.
const IdToDefMap& id_to_defs() const { return id_to_def_; }
// Returns the map from ids to their uses in instructions.
const IdToUsesMap& id_to_uses() const { return id_to_uses_; }
// Turns the instruction defining the given |id| into a Nop. Returns true on
// success, false if the given |id| is not defined at all. This method also
// erases both the uses of |id| and the information of this |id|-generating
// instruction's uses of its operands.
bool KillDef(uint32_t id);
// Turns the given instruction |inst| to a Nop. This method erases the
// information of the given instruction's uses of its operands. If |inst|
// defines an result id, the uses of the result id will also be erased.
void KillInst(ir::Instruction* inst);
// Replaces all uses of |before| id with |after| id. Returns true if any
// replacement happens. This method does not kill the definition of the
// |before| id. If |after| is the same as |before|, does nothing and returns
// false.
bool ReplaceAllUsesWith(uint32_t before, uint32_t after);
private:
using InstToUsedIdsMap =
std::unordered_map<const ir::Instruction*, std::vector<uint32_t>>;
// Analyzes the defs and uses in the given |module| and populates data
// structures in this class. Does nothing if |module| is nullptr.
void AnalyzeDefUse(ir::Module* module);
// Clear the internal def-use record of the given instruction |inst|. This
// method will update the use information of the operand ids of |inst|. The
// record: |inst| uses an |id|, will be removed from the use records of |id|.
// If |inst| defines an result id, the use record of this result id will also
// be removed. Does nothing if |inst| was not analyzed before.
void ClearInst(ir::Instruction* inst);
// Erases the records that a given instruction uses its operand ids.
void EraseUseRecordsOfOperandIds(const ir::Instruction* inst);
const MessageConsumer& consumer_; // Message consumer.
IdToDefMap id_to_def_; // Mapping from ids to their definitions
IdToUsesMap id_to_uses_; // Mapping from ids to their uses
// Mapping from instructions to the ids used in the instructions generating
// the result ids.
InstToUsedIdsMap inst_to_used_ids_;
};
} // namespace analysis
} // namespace opt
} // namespace spvtools
#endif // LIBSPIRV_OPT_DEF_USE_MANAGER_H_