1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2  * vim: set ts=8 sts=2 et sw=2 tw=80:
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/. */
6 
7 #ifndef jit_ICStubSpace_h
8 #define jit_ICStubSpace_h
9 
10 #include "ds/LifoAlloc.h"
11 
12 namespace js {
13 namespace jit {
14 
15 // ICStubSpace is an abstraction for allocation policy and storage for CacheIR
16 // stub data. There are two kinds of Baseline CacheIR stubs:
17 //
18 // (1) CacheIR stubs that can make non-tail calls that can GC. These are
19 //     allocated in a LifoAlloc stored in JitScript.
20 //     See JitScriptICStubSpace.
21 //
22 // (2) Other CacheIR stubs (aka optimized IC stubs). Allocated in a per-Zone
23 //     LifoAlloc and purged when JIT-code is discarded.
24 //     See OptimizedICStubSpace.
25 class ICStubSpace {
26  protected:
27   LifoAlloc allocator_;
28 
ICStubSpace(size_t chunkSize)29   explicit ICStubSpace(size_t chunkSize) : allocator_(chunkSize) {}
30 
31  public:
alloc(size_t size)32   inline void* alloc(size_t size) { return allocator_.alloc(size); }
33 
34   JS_DECLARE_NEW_METHODS(allocate, alloc, inline)
35 
36   void freeAllAfterMinorGC(JS::Zone* zone);
37 
38 #ifdef DEBUG
isEmpty()39   bool isEmpty() const { return allocator_.isEmpty(); }
40 #endif
41 
sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf)42   size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
43     return allocator_.sizeOfExcludingThis(mallocSizeOf);
44   }
45 };
46 
47 // Space for optimized stubs. Every JitZone has a single OptimizedICStubSpace.
48 struct OptimizedICStubSpace : public ICStubSpace {
49   static const size_t STUB_DEFAULT_CHUNK_SIZE = 4096;
50 
51  public:
OptimizedICStubSpaceOptimizedICStubSpace52   OptimizedICStubSpace() : ICStubSpace(STUB_DEFAULT_CHUNK_SIZE) {}
53 };
54 
55 // Space for Can-GC stubs. Every JitScript has a JitScriptICStubSpace.
56 struct JitScriptICStubSpace : public ICStubSpace {
57   static const size_t STUB_DEFAULT_CHUNK_SIZE = 4096;
58 
59  public:
JitScriptICStubSpaceJitScriptICStubSpace60   JitScriptICStubSpace() : ICStubSpace(STUB_DEFAULT_CHUNK_SIZE) {}
61 };
62 
63 }  // namespace jit
64 }  // namespace js
65 
66 #endif /* jit_ICStubSpace_h */
67