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 stub 16 // data. There are two kinds of stubs: optimized stubs and fallback stubs (the 17 // latter also includes stubs that can make non-tail calls that can GC). 18 // 19 // Optimized stubs are allocated per-compartment and are always purged when 20 // JIT-code is discarded. Fallback stubs are allocated per BaselineScript and 21 // are only destroyed when the BaselineScript is destroyed. 22 class ICStubSpace { 23 protected: 24 LifoAlloc allocator_; 25 ICStubSpace(size_t chunkSize)26 explicit ICStubSpace(size_t chunkSize) : allocator_(chunkSize) {} 27 28 public: alloc(size_t size)29 inline void* alloc(size_t size) { return allocator_.alloc(size); } 30 31 JS_DECLARE_NEW_METHODS(allocate, alloc, inline) 32 33 void freeAllAfterMinorGC(JS::Zone* zone); 34 35 #ifdef DEBUG isEmpty()36 bool isEmpty() const { return allocator_.isEmpty(); } 37 #endif 38 sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf)39 size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const { 40 return allocator_.sizeOfExcludingThis(mallocSizeOf); 41 } 42 }; 43 44 // Space for optimized stubs. Every JitRealm has a single 45 // OptimizedICStubSpace. 46 struct OptimizedICStubSpace : public ICStubSpace { 47 static const size_t STUB_DEFAULT_CHUNK_SIZE = 4096; 48 49 public: OptimizedICStubSpaceOptimizedICStubSpace50 OptimizedICStubSpace() : ICStubSpace(STUB_DEFAULT_CHUNK_SIZE) {} 51 }; 52 53 // Space for fallback stubs. Every BaselineScript has a 54 // FallbackICStubSpace. 55 struct FallbackICStubSpace : public ICStubSpace { 56 static const size_t STUB_DEFAULT_CHUNK_SIZE = 4096; 57 58 public: FallbackICStubSpaceFallbackICStubSpace59 FallbackICStubSpace() : ICStubSpace(STUB_DEFAULT_CHUNK_SIZE) {} 60 }; 61 62 } // namespace jit 63 } // namespace js 64 65 #endif /* jit_ICStubSpace_h */ 66