1 //===- WasmTraits.h - DenseMap traits for the Wasm structures ---*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file provides llvm::DenseMapInfo traits for the Wasm structures.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_BINARYFORMAT_WASMTRAITS_H
14 #define LLVM_BINARYFORMAT_WASMTRAITS_H
15 
16 #include "llvm/ADT/Hashing.h"
17 #include "llvm/BinaryFormat/Wasm.h"
18 
19 namespace llvm {
20 
21 template <typename T> struct DenseMapInfo;
22 
23 // Traits for using WasmSignature in a DenseMap.
24 template <> struct DenseMapInfo<wasm::WasmSignature> {
25   static wasm::WasmSignature getEmptyKey() {
26     wasm::WasmSignature Sig;
27     Sig.State = wasm::WasmSignature::Empty;
28     return Sig;
29   }
30   static wasm::WasmSignature getTombstoneKey() {
31     wasm::WasmSignature Sig;
32     Sig.State = wasm::WasmSignature::Tombstone;
33     return Sig;
34   }
35   static unsigned getHashValue(const wasm::WasmSignature &Sig) {
36     uintptr_t H = hash_value(Sig.State);
37     for (auto Ret : Sig.Returns)
38       H = hash_combine(H, Ret);
39     for (auto Param : Sig.Params)
40       H = hash_combine(H, Param);
41     return H;
42   }
43   static bool isEqual(const wasm::WasmSignature &LHS,
44                       const wasm::WasmSignature &RHS) {
45     return LHS == RHS;
46   }
47 };
48 
49 // Traits for using WasmGlobalType in a DenseMap
50 template <> struct DenseMapInfo<wasm::WasmGlobalType> {
51   static wasm::WasmGlobalType getEmptyKey() {
52     return wasm::WasmGlobalType{1, true};
53   }
54   static wasm::WasmGlobalType getTombstoneKey() {
55     return wasm::WasmGlobalType{2, true};
56   }
57   static unsigned getHashValue(const wasm::WasmGlobalType &GlobalType) {
58     return hash_combine(GlobalType.Type, GlobalType.Mutable);
59   }
60   static bool isEqual(const wasm::WasmGlobalType &LHS,
61                       const wasm::WasmGlobalType &RHS) {
62     return LHS == RHS;
63   }
64 };
65 
66 // Traits for using WasmLimits in a DenseMap
67 template <> struct DenseMapInfo<wasm::WasmLimits> {
68   static wasm::WasmLimits getEmptyKey() {
69     return wasm::WasmLimits{0xff, 0xff, 0xff};
70   }
71   static wasm::WasmLimits getTombstoneKey() {
72     return wasm::WasmLimits{0xee, 0xee, 0xee};
73   }
74   static unsigned getHashValue(const wasm::WasmLimits &Limits) {
75     unsigned Hash = hash_value(Limits.Flags);
76     Hash = hash_combine(Hash, Limits.Minimum);
77     if (Limits.Flags & llvm::wasm::WASM_LIMITS_FLAG_HAS_MAX) {
78       Hash = hash_combine(Hash, Limits.Maximum);
79     }
80     return Hash;
81   }
82   static bool isEqual(const wasm::WasmLimits &LHS,
83                       const wasm::WasmLimits &RHS) {
84     return LHS == RHS;
85   }
86 };
87 
88 // Traits for using WasmTableType in a DenseMap
89 template <> struct DenseMapInfo<wasm::WasmTableType> {
90   static wasm::WasmTableType getEmptyKey() {
91     return wasm::WasmTableType{0,
92                                DenseMapInfo<wasm::WasmLimits>::getEmptyKey()};
93   }
94   static wasm::WasmTableType getTombstoneKey() {
95     return wasm::WasmTableType{
96         1, DenseMapInfo<wasm::WasmLimits>::getTombstoneKey()};
97   }
98   static unsigned getHashValue(const wasm::WasmTableType &TableType) {
99     return hash_combine(
100         TableType.ElemType,
101         DenseMapInfo<wasm::WasmLimits>::getHashValue(TableType.Limits));
102   }
103   static bool isEqual(const wasm::WasmTableType &LHS,
104                       const wasm::WasmTableType &RHS) {
105     return LHS == RHS;
106   }
107 };
108 
109 } // end namespace llvm
110 
111 #endif // LLVM_BINARYFORMAT_WASMTRAITS_H
112