| /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- |
| * vim: set ts=8 sts=4 et sw=4 tw=99: |
| * This Source Code Form is subject to the terms of the Mozilla Public |
| * License, v. 2.0. If a copy of the MPL was not distributed with this |
| * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| |
| #ifndef jit_StupidAllocator_h |
| #define jit_StupidAllocator_h |
| |
| #include "jit/RegisterAllocator.h" |
| |
| // Simple register allocator that only carries registers within basic blocks. |
| |
| namespace js { |
| namespace jit { |
| |
| class StupidAllocator : public RegisterAllocator |
| { |
| static const uint32_t MAX_REGISTERS = AnyRegister::Total; |
| static const uint32_t MISSING_ALLOCATION = UINT32_MAX; |
| |
| struct AllocatedRegister { |
| AnyRegister reg; |
| |
| // The type of the value in the register. |
| LDefinition::Type type; |
| |
| // Virtual register this physical reg backs, or MISSING_ALLOCATION. |
| uint32_t vreg; |
| |
| // id of the instruction which most recently used this register. |
| uint32_t age; |
| |
| // Whether the physical register is not synced with the backing stack slot. |
| bool dirty; |
| |
| void set(uint32_t vreg, LInstruction* ins = nullptr, bool dirty = false) { |
| this->vreg = vreg; |
| this->age = ins ? ins->id() : 0; |
| this->dirty = dirty; |
| } |
| }; |
| |
| // Active allocation for the current code position. |
| mozilla::Array<AllocatedRegister, MAX_REGISTERS> registers; |
| uint32_t registerCount; |
| |
| // Type indicating an index into registers. |
| typedef uint32_t RegisterIndex; |
| |
| // Information about each virtual register. |
| Vector<LDefinition*, 0, SystemAllocPolicy> virtualRegisters; |
| |
| public: |
| StupidAllocator(MIRGenerator* mir, LIRGenerator* lir, LIRGraph& graph) |
| : RegisterAllocator(mir, lir, graph) |
| { |
| } |
| |
| bool go(); |
| |
| private: |
| bool init(); |
| |
| void syncForBlockEnd(LBlock* block, LInstruction* ins); |
| void allocateForInstruction(LInstruction* ins); |
| void allocateForDefinition(LInstruction* ins, LDefinition* def); |
| |
| LAllocation* stackLocation(uint32_t vreg); |
| |
| RegisterIndex registerIndex(AnyRegister reg); |
| |
| AnyRegister ensureHasRegister(LInstruction* ins, uint32_t vreg); |
| RegisterIndex allocateRegister(LInstruction* ins, uint32_t vreg); |
| |
| void syncRegister(LInstruction* ins, RegisterIndex index); |
| void evictRegister(LInstruction* ins, RegisterIndex index); |
| void evictAliasedRegister(LInstruction* ins, RegisterIndex index); |
| void loadRegister(LInstruction* ins, uint32_t vreg, RegisterIndex index, LDefinition::Type type); |
| |
| RegisterIndex findExistingRegister(uint32_t vreg); |
| |
| bool allocationRequiresRegister(const LAllocation* alloc, AnyRegister reg); |
| bool registerIsReserved(LInstruction* ins, AnyRegister reg); |
| }; |
| |
| } // namespace jit |
| } // namespace js |
| |
| #endif /* jit_StupidAllocator_h */ |