• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /**
2  * Copyright (c) 2021-2022 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef COMPILER_OPTIMIZER_OPTIMIZATIONS_REGALLOC_SPILL_FILLS_RESOLVER_H
17 #define COMPILER_OPTIMIZER_OPTIMIZATIONS_REGALLOC_SPILL_FILLS_RESOLVER_H
18 
19 #include "compiler/optimizer/ir/graph_visitor.h"
20 #include "optimizer/code_generator/registers_description.h"
21 #include "optimizer/ir/inst.h"
22 #include "utils/arena_containers.h"
23 
24 namespace panda::compiler {
25 class RegAllocBase;
26 
27 /*
28  * There are 3 spill-fill location types:
29  * - general register
30  * - vector register
31  * - stack slot
32  *
33  * Each spill-fill's source and destination is described by index inside these locations;
34  *
35  * Since  all destinations are unique, we can use them as keys for table, which collects information about
36  * all moves:
37  * - genenral register index maps to table key one by one
38  * - vector register index offsets on number of genenral registers (MAX_NUM_REGS)
39  * - stack slot index offsets on number of all registers (MAX_NUM_REGS + MAX_NUM_VREGS)
40  *
41  * Iterating over this table `SpillFillsResolver` builds non-conflict chains of spill-fills.
42  * Building process is described before `SpillFillsResolver::Reorder()` method.
43  */
44 class SpillFillsResolver : public GraphVisitor {
45     static_assert(sizeof(Register) == sizeof(StackSlot), "Register and StackSlot should be the same size");
46 
47     using LocationIndex = uint16_t;
48     static constexpr auto INVALID_LOCATION_INDEX = std::numeric_limits<LocationIndex>::max();
49 
50     struct LocationInfo {
51         LocationType location;
52         LocationIndex idx;
53     };
54 
55     struct MoveInfo {
56         LocationIndex src;
57         DataType::Type reg_type;
58     };
59 
60 public:
61     explicit SpillFillsResolver(Graph *graph);
62     SpillFillsResolver(Graph *graph, Register resolver, size_t regs_count, size_t vregs_count = 0);
63     NO_COPY_SEMANTIC(SpillFillsResolver);
64     NO_MOVE_SEMANTIC(SpillFillsResolver);
65     ~SpillFillsResolver() override = default;
66 
67     const ArenaVector<BasicBlock *> &GetBlocksToVisit() const override;
68 
69     void Run();
70 
71     void Resolve(SpillFillInst *spill_fill_inst);
72 
73     void ResolveIfRequired(SpillFillInst *spill_fill_inst);
74 
75     Graph *GetGraph() const;
76 
77 protected:
78     static void VisitSpillFill(GraphVisitor *v, Inst *inst);
79 
80 private:
81     bool NeedToResolve(const ArenaVector<SpillFillData> &spill_fills);
82     void ResolveCallSpillFill(SpillFillInst *spill_fill_inst);
83     void CollectSpillFillsData(SpillFillInst *spill_fill_inst);
84     void Reorder(SpillFillInst *spill_fill_inst);
85     LocationIndex CheckAndResolveCyclicDependency(LocationIndex dst_first);
86     template <bool ciclyc>
87     void AddMovesChain(LocationIndex dst, ArenaVector<LocationIndex> *remap, SpillFillInst *spill_fill_inst);
88     LocationIndex GetResolver(DataType::Type type);
89 
90     // Get table index by Location type
Map(Location location)91     LocationIndex Map(Location location)
92     {
93         if (location.IsRegister()) {
94             return location.GetValue();
95         }
96         if (location.IsFpRegister()) {
97             return location.GetValue() + VREGS_TABLE_OFFSET;
98         }
99         if (location.IsStack()) {
100             return location.GetValue() + SLOTS_TABLE_OFFSET;
101         }
102         ASSERT(location.IsStackParameter());
103         return location.GetValue() + PARAMETER_SLOTS_OFFSET;
104     }
105 
106     // Fetch location type and element number inside this location from table index
ToLocation(LocationIndex reg)107     Location ToLocation(LocationIndex reg)
108     {
109         if (reg >= PARAMETER_SLOTS_OFFSET) {
110             return Location::MakeStackParameter(reg - PARAMETER_SLOTS_OFFSET);
111         }
112         if (reg >= SLOTS_TABLE_OFFSET) {
113             return Location::MakeStackSlot(reg - SLOTS_TABLE_OFFSET);
114         }
115         if (reg >= VREGS_TABLE_OFFSET) {
116             return Location::MakeFpRegister(reg - VREGS_TABLE_OFFSET);
117         }
118         return Location::MakeRegister(reg);
119     }
120 
IsPairedReg(Arch arch,DataType::Type type)121     static inline bool IsPairedReg(Arch arch, DataType::Type type)
122     {
123         return arch != Arch::NONE && !Is64BitsArch(arch) && Is64Bits(type, arch);
124     }
125 
126 private:
127     Graph *graph_ {nullptr};
128     ArenaVector<MoveInfo> moves_table_;
129     ArenaVector<uint8_t> loads_count_;
130     // Group of moves which can be safely inserted before all others
131     ArenaVector<SpillFillData> pre_moves_;
132     // Group of moves which can be safely inserted after all others
133     ArenaVector<SpillFillData> post_moves_;
134     Register resolver_;
135 
136     const size_t VREGS_TABLE_OFFSET;
137     const size_t SLOTS_TABLE_OFFSET;
138     const size_t PARAMETER_SLOTS_OFFSET;
139     const size_t LOCATIONS_COUNT;
140     ArenaVector<bool> reg_write_;
141     ArenaVector<bool> stack_write_;
142 
143 #include "optimizer/ir/visitor.inc"
144 };
145 }  // namespace panda::compiler
146 
147 #endif  // COMPILER_OPTIMIZER_OPTIMIZATIONS_REGALLOC_SPILL_FILLS_RESOLVER_H
148