mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-10-19 11:30:15 +00:00
75 lines
2.5 KiB
C
75 lines
2.5 KiB
C
|
// 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_VALUE_NUMBER_TABLE_H_
|
||
|
#define LIBSPIRV_OPT_VALUE_NUMBER_TABLE_H_
|
||
|
|
||
|
#include <cstdint>
|
||
|
#include <unordered_map>
|
||
|
#include "instruction.h"
|
||
|
#include "ir_context.h"
|
||
|
|
||
|
namespace spvtools {
|
||
|
namespace opt {
|
||
|
|
||
|
// Returns true if the two instructions compute the same value. Used by the
|
||
|
// value number table to compare two instructions.
|
||
|
class ComputeSameValue {
|
||
|
public:
|
||
|
bool operator()(const ir::Instruction& lhs, const ir::Instruction& rhs) const;
|
||
|
};
|
||
|
|
||
|
// The hash function used in the value number table.
|
||
|
class ValueTableHash {
|
||
|
public:
|
||
|
std::size_t operator()(const spvtools::ir::Instruction& inst) const;
|
||
|
};
|
||
|
|
||
|
// This class implements the value number analysis. It is using a hash-based
|
||
|
// approach to value numbering. For now, it is very simple, and computes value
|
||
|
// numbers for instructions when they are asked for via |GetValueNumber|. This
|
||
|
// may change in the future and should not be relied on.
|
||
|
class ValueNumberTable {
|
||
|
public:
|
||
|
ValueNumberTable(ir::IRContext* ctx) : context_(ctx), next_value_number_(1) {}
|
||
|
|
||
|
// Returns the value number of the value computed by |inst|. |inst| must have
|
||
|
// a result id that will hold the computed value.
|
||
|
uint32_t GetValueNumber(spvtools::ir::Instruction* inst);
|
||
|
|
||
|
// Returns the value number of the value contain in |id|.
|
||
|
inline uint32_t GetValueNumber(uint32_t id);
|
||
|
|
||
|
ir::IRContext* context() { return context_; }
|
||
|
|
||
|
private:
|
||
|
std::unordered_map<spvtools::ir::Instruction, uint32_t, ValueTableHash,
|
||
|
ComputeSameValue>
|
||
|
instruction_to_value_;
|
||
|
std::unordered_map<uint32_t, uint32_t> id_to_value_;
|
||
|
ir::IRContext* context_;
|
||
|
uint32_t next_value_number_;
|
||
|
|
||
|
uint32_t TakeNextValueNumber() { return next_value_number_++; }
|
||
|
};
|
||
|
|
||
|
uint32_t ValueNumberTable::GetValueNumber(uint32_t id) {
|
||
|
return GetValueNumber(context()->get_def_use_mgr()->GetDef(id));
|
||
|
}
|
||
|
|
||
|
} // namespace opt
|
||
|
} // namespace spvtools
|
||
|
|
||
|
#endif // LIBSPIRV_OPT_VALUE_NUMBER_TABLE_H_
|