js/src/jit/StupidAllocator.h@129ffea94266
js/src/jit/StupidAllocator.h
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2 * vim: set ts=8 sts=4 et sw=4 tw=99:
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
7 #ifndef jit_StupidAllocator_h
8 #define jit_StupidAllocator_h
10 #include "jit/RegisterAllocator.h"
12 // Simple register allocator that only carries registers within basic blocks.
14 namespace js {
15 namespace jit {
17 class StupidAllocator : public RegisterAllocator
18 {
19 static const uint32_t MAX_REGISTERS = Registers::Allocatable + FloatRegisters::Allocatable;
20 static const uint32_t MISSING_ALLOCATION = UINT32_MAX;
22 struct AllocatedRegister {
23 AnyRegister reg;
25 // The type of the value in the register.
26 LDefinition::Type type;
28 // Virtual register this physical reg backs, or MISSING_ALLOCATION.
29 uint32_t vreg;
31 // id of the instruction which most recently used this register.
32 uint32_t age;
34 // Whether the physical register is not synced with the backing stack slot.
35 bool dirty;
37 void set(uint32_t vreg, LInstruction *ins = nullptr, bool dirty = false) {
38 this->vreg = vreg;
39 this->age = ins ? ins->id() : 0;
40 this->dirty = dirty;
41 }
42 };
44 // Active allocation for the current code position.
45 mozilla::Array<AllocatedRegister, MAX_REGISTERS> registers;
46 uint32_t registerCount;
48 // Type indicating an index into registers.
49 typedef uint32_t RegisterIndex;
51 // Information about each virtual register.
52 Vector<LDefinition*, 0, SystemAllocPolicy> virtualRegisters;
54 public:
55 StupidAllocator(MIRGenerator *mir, LIRGenerator *lir, LIRGraph &graph)
56 : RegisterAllocator(mir, lir, graph)
57 {
58 }
60 bool go();
62 private:
63 bool init();
65 void syncForBlockEnd(LBlock *block, LInstruction *ins);
66 void allocateForInstruction(LInstruction *ins);
67 void allocateForDefinition(LInstruction *ins, LDefinition *def);
69 LAllocation *stackLocation(uint32_t vreg);
71 RegisterIndex registerIndex(AnyRegister reg);
73 AnyRegister ensureHasRegister(LInstruction *ins, uint32_t vreg);
74 RegisterIndex allocateRegister(LInstruction *ins, uint32_t vreg);
76 void syncRegister(LInstruction *ins, RegisterIndex index);
77 void evictRegister(LInstruction *ins, RegisterIndex index);
78 void loadRegister(LInstruction *ins, uint32_t vreg, RegisterIndex index, LDefinition::Type type);
80 RegisterIndex findExistingRegister(uint32_t vreg);
82 bool allocationRequiresRegister(const LAllocation *alloc, AnyRegister reg);
83 bool registerIsReserved(LInstruction *ins, AnyRegister reg);
84 };
86 } // namespace jit
87 } // namespace js
89 #endif /* jit_StupidAllocator_h */
