1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
/*
* Copyright 2016 WebAssembly Community Group participants
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef wasm_wasm_emscripten_h
#define wasm_wasm_emscripten_h
#include "wasm.h"
#include "wasm-builder.h"
#include "support/file.h"
namespace wasm {
// Class which modifies a wasm module for use with emscripten. Generates
// runtime functions and emits metadata.
class EmscriptenGlueGenerator {
public:
EmscriptenGlueGenerator(Module& wasm, Address stackPointerOffset = Address(0))
: wasm(wasm),
builder(wasm),
stackPointerOffset(stackPointerOffset),
useStackPointerGlobal(stackPointerOffset == 0) { }
void generateRuntimeFunctions();
Function* generateMemoryGrowthFunction();
Function* generateAssignGOTEntriesFunction();
void generateStackInitialization(Address addr);
void generatePostInstantiateFunction();
// Create thunks for use with emscripten Runtime.dynCall. Creates one for each
// signature in the indirect function table.
void generateDynCallThunks();
// Convert stack pointer access from global.get/global.set to calling save
// and restore functions.
void replaceStackPointerGlobal();
std::string generateEmscriptenMetadata(
Address staticBump, std::vector<Name> const& initializerFunctions,
FeatureSet features);
void fixInvokeFunctionNames();
// Emits the data segments to a file. The file contains data from address base
// onwards (we must pass in base, as we can't tell it from the wasm - the first
// segment may start after a run of zeros, but we need those zeros in the file).
void separateDataSegments(Output* outfile, Address base);
private:
Module& wasm;
Builder builder;
Address stackPointerOffset;
bool useStackPointerGlobal;
Global* getStackPointerGlobal();
Expression* generateLoadStackPointer();
Expression* generateStoreStackPointer(Expression* value);
void generateStackSaveFunction();
void generateStackAllocFunction();
void generateStackRestoreFunction();
};
} // namespace wasm
#endif // wasm_wasm_emscripten_h
|
