1 // Copyright 2015 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_AST_DECODER_H_
6 #define V8_WASM_AST_DECODER_H_
7
8 #include "src/signature.h"
9 #include "src/wasm/wasm-opcodes.h"
10 #include "src/wasm/wasm-result.h"
11
12 namespace v8 {
13 namespace internal {
14
15 namespace compiler { // external declarations from compiler.
16 class WasmGraphBuilder;
17 }
18
19 namespace wasm {
20
21 typedef compiler::WasmGraphBuilder TFBuilder;
22 struct ModuleEnv; // forward declaration of module interface.
23
24 // Interface the function environment during decoding, include the signature
25 // and number of locals.
26 struct FunctionEnv {
27 ModuleEnv* module; // module environment
28 FunctionSig* sig; // signature of this function
29 uint32_t local_int32_count; // number of int32 locals
30 uint32_t local_int64_count; // number of int64 locals
31 uint32_t local_float32_count; // number of float32 locals
32 uint32_t local_float64_count; // number of float64 locals
33 uint32_t total_locals; // sum of parameters and all locals
34
IsValidLocalFunctionEnv35 bool IsValidLocal(uint32_t index) { return index < total_locals; }
GetLocalCountFunctionEnv36 uint32_t GetLocalCount() { return total_locals; }
GetLocalTypeFunctionEnv37 LocalType GetLocalType(uint32_t index) {
38 if (index < static_cast<uint32_t>(sig->parameter_count())) {
39 return sig->GetParam(index);
40 }
41 index -= static_cast<uint32_t>(sig->parameter_count());
42 if (index < local_int32_count) return kAstI32;
43 index -= local_int32_count;
44 if (index < local_int64_count) return kAstI64;
45 index -= local_int64_count;
46 if (index < local_float32_count) return kAstF32;
47 index -= local_float32_count;
48 if (index < local_float64_count) return kAstF64;
49 return kAstStmt;
50 }
51
AddLocalsFunctionEnv52 void AddLocals(LocalType type, uint32_t count) {
53 switch (type) {
54 case kAstI32:
55 local_int32_count += count;
56 break;
57 case kAstI64:
58 local_int64_count += count;
59 break;
60 case kAstF32:
61 local_float32_count += count;
62 break;
63 case kAstF64:
64 local_float64_count += count;
65 break;
66 default:
67 UNREACHABLE();
68 }
69 total_locals += count;
70 DCHECK(total_locals ==
71 (sig->parameter_count() + local_int32_count + local_int64_count +
72 local_float32_count + local_float64_count));
73 }
74
SumLocalsFunctionEnv75 void SumLocals() {
76 total_locals = static_cast<uint32_t>(sig->parameter_count()) +
77 local_int32_count + local_int64_count + local_float32_count +
78 local_float64_count;
79 }
80 };
81
82 struct Tree;
83 typedef Result<Tree*> TreeResult;
84
85 std::ostream& operator<<(std::ostream& os, const Tree& tree);
86
87 TreeResult VerifyWasmCode(FunctionEnv* env, const byte* base, const byte* start,
88 const byte* end);
89 TreeResult BuildTFGraph(TFBuilder* builder, FunctionEnv* env, const byte* base,
90 const byte* start, const byte* end);
91
VerifyWasmCode(FunctionEnv * env,const byte * start,const byte * end)92 inline TreeResult VerifyWasmCode(FunctionEnv* env, const byte* start,
93 const byte* end) {
94 return VerifyWasmCode(env, nullptr, start, end);
95 }
96
BuildTFGraph(TFBuilder * builder,FunctionEnv * env,const byte * start,const byte * end)97 inline TreeResult BuildTFGraph(TFBuilder* builder, FunctionEnv* env,
98 const byte* start, const byte* end) {
99 return BuildTFGraph(builder, env, nullptr, start, end);
100 }
101
102 enum ReadUnsignedLEB128ErrorCode { kNoError, kInvalidLEB128, kMissingLEB128 };
103
104 ReadUnsignedLEB128ErrorCode ReadUnsignedLEB128Operand(const byte*, const byte*,
105 int*, uint32_t*);
106
107 // Computes the length of the opcode at the given address.
108 int OpcodeLength(const byte* pc);
109
110 // Computes the arity (number of sub-nodes) of the opcode at the given address.
111 int OpcodeArity(FunctionEnv* env, const byte* pc);
112 } // namespace wasm
113 } // namespace internal
114 } // namespace v8
115
116 #endif // V8_WASM_AST_DECODER_H_
117