1 | // Copyright 2016 the V8 project authors. All rights reserved. |
2 | // Use of this source code is governed by a BSD-style license that can be |
3 | // found in the LICENSE file. |
4 | |
5 | #ifndef V8_WASM_SIGNATURE_MAP_H_ |
6 | #define V8_WASM_SIGNATURE_MAP_H_ |
7 | |
8 | #include <unordered_map> |
9 | |
10 | #include "src/signature.h" |
11 | #include "src/wasm/value-type.h" |
12 | |
13 | namespace v8 { |
14 | namespace internal { |
15 | |
16 | namespace wasm { |
17 | |
18 | // A signature map canonicalizes signatures into a range of indices so that |
19 | // two different {FunctionSig} instances with the same contents map to the |
20 | // same index. |
21 | class V8_EXPORT_PRIVATE SignatureMap { |
22 | public: |
23 | // Allow default construction and move construction (because we have vectors |
24 | // of objects containing SignatureMaps), but disallow copy or assign. It's |
25 | // too easy to get security bugs by accidentally updating a copy of the map. |
26 | MOVE_ONLY_WITH_DEFAULT_CONSTRUCTORS(SignatureMap); |
27 | |
28 | // Gets the index for a signature, assigning a new index if necessary. |
29 | uint32_t FindOrInsert(const FunctionSig& sig); |
30 | |
31 | // Gets the index for a signature, returning {-1} if not found. |
32 | int32_t Find(const FunctionSig& sig) const; |
33 | |
34 | // Disallows further insertions to this signature map. |
35 | void Freeze() { frozen_ = true; } |
36 | |
37 | private: |
38 | bool frozen_ = false; |
39 | std::unordered_map<FunctionSig, uint32_t, base::hash<FunctionSig>> map_; |
40 | }; |
41 | |
42 | } // namespace wasm |
43 | } // namespace internal |
44 | } // namespace v8 |
45 | |
46 | #endif // V8_WASM_SIGNATURE_MAP_H_ |
47 | |