1 //==-- WebAssemblyTargetStreamer.cpp - WebAssembly Target Streamer Methods --=//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// This file defines WebAssembly-specific target streamer classes.
12 /// These are for implementing support for target-specific assembly directives.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "WebAssemblyTargetStreamer.h"
17 #include "InstPrinter/WebAssemblyInstPrinter.h"
18 #include "WebAssemblyMCTargetDesc.h"
19 #include "llvm/MC/MCContext.h"
20 #include "llvm/MC/MCSectionWasm.h"
21 #include "llvm/MC/MCSubtargetInfo.h"
22 #include "llvm/MC/MCSymbolWasm.h"
23 #include "llvm/Support/Casting.h"
24 #include "llvm/Support/ErrorHandling.h"
25 #include "llvm/Support/FormattedStream.h"
26 using namespace llvm;
27 
28 WebAssemblyTargetStreamer::WebAssemblyTargetStreamer(MCStreamer &S)
29     : MCTargetStreamer(S) {}
30 
31 void WebAssemblyTargetStreamer::emitValueType(wasm::ValType Type) {
32   Streamer.EmitIntValue(uint8_t(Type), 1);
33 }
34 
35 WebAssemblyTargetAsmStreamer::WebAssemblyTargetAsmStreamer(
36     MCStreamer &S, formatted_raw_ostream &OS)
37     : WebAssemblyTargetStreamer(S), OS(OS) {}
38 
39 WebAssemblyTargetWasmStreamer::WebAssemblyTargetWasmStreamer(MCStreamer &S)
40     : WebAssemblyTargetStreamer(S) {}
41 
42 static void PrintTypes(formatted_raw_ostream &OS, ArrayRef<wasm::ValType> Types) {
43   bool First = true;
44   for (auto Type : Types) {
45     if (First)
46       First = false;
47     else
48       OS << ", ";
49     OS << WebAssembly::TypeToString(Type);
50   }
51   OS << '\n';
52 }
53 
54 void WebAssemblyTargetAsmStreamer::emitLocal(ArrayRef<wasm::ValType> Types) {
55   if (!Types.empty()) {
56     OS << "\t.local  \t";
57     PrintTypes(OS, Types);
58   }
59 }
60 
61 void WebAssemblyTargetAsmStreamer::emitEndFunc() { OS << "\t.endfunc\n"; }
62 
63 void WebAssemblyTargetAsmStreamer::emitFunctionType(MCSymbolWasm *Symbol) {
64   OS << "\t.functype\t" << Symbol->getName() << " (";
65   auto &Params = Symbol->getSignature()->Params;
66   for (auto &Ty : Params) {
67     if (&Ty != &Params[0]) OS << ", ";
68     OS << WebAssembly::TypeToString(Ty);
69   }
70   OS << ") -> (";
71   auto &Returns = Symbol->getSignature()->Returns;
72   for (auto &Ty : Returns) {
73     if (&Ty != &Returns[0]) OS << ", ";
74     OS << WebAssembly::TypeToString(Ty);
75   }
76   OS << ")\n";
77 }
78 
79 void WebAssemblyTargetAsmStreamer::emitGlobalType(MCSymbolWasm *Sym) {
80   assert(Sym->isGlobal());
81   OS << "\t.globaltype\t" << Sym->getName() << ", " <<
82         WebAssembly::TypeToString(
83           static_cast<wasm::ValType>(Sym->getGlobalType().Type)) <<
84         '\n';
85 }
86 
87 void WebAssemblyTargetAsmStreamer::emitEventType(MCSymbolWasm *Sym) {
88   assert(Sym->isEvent());
89   OS << "\t.eventtype\t" << Sym->getName();
90   if (Sym->getSignature()->Returns.empty())
91     OS << ", void";
92   else {
93     assert(Sym->getSignature()->Returns.size() == 1);
94     OS << ", "
95        << WebAssembly::TypeToString(Sym->getSignature()->Returns.front());
96   }
97   for (auto Ty : Sym->getSignature()->Params)
98     OS << ", " << WebAssembly::TypeToString(Ty);
99   OS << '\n';
100 }
101 
102 void WebAssemblyTargetAsmStreamer::emitImportModule(MCSymbolWasm *Sym,
103                                                     StringRef ModuleName) {
104   OS << "\t.import_module\t" << Sym->getName() << ", " << ModuleName << '\n';
105 }
106 
107 void WebAssemblyTargetAsmStreamer::emitIndIdx(const MCExpr *Value) {
108   OS << "\t.indidx  \t" << *Value << '\n';
109 }
110 
111 void WebAssemblyTargetWasmStreamer::emitLocal(ArrayRef<wasm::ValType> Types) {
112   SmallVector<std::pair<wasm::ValType, uint32_t>, 4> Grouped;
113   for (auto Type : Types) {
114     if (Grouped.empty() || Grouped.back().first != Type)
115       Grouped.push_back(std::make_pair(Type, 1));
116     else
117       ++Grouped.back().second;
118   }
119 
120   Streamer.EmitULEB128IntValue(Grouped.size());
121   for (auto Pair : Grouped) {
122     Streamer.EmitULEB128IntValue(Pair.second);
123     emitValueType(Pair.first);
124   }
125 }
126 
127 void WebAssemblyTargetWasmStreamer::emitEndFunc() {
128   llvm_unreachable(".end_func is not needed for direct wasm output");
129 }
130 
131 void WebAssemblyTargetWasmStreamer::emitIndIdx(const MCExpr *Value) {
132   llvm_unreachable(".indidx encoding not yet implemented");
133 }
134 
135 void WebAssemblyTargetWasmStreamer::emitFunctionType(MCSymbolWasm *Symbol) {
136   // Symbol already has its arguments and result set.
137   Symbol->setType(wasm::WASM_SYMBOL_TYPE_FUNCTION);
138 }
139 
140 void WebAssemblyTargetWasmStreamer::emitGlobalType(MCSymbolWasm *Sym) {
141   // Not needed.
142 }
143 
144 void WebAssemblyTargetWasmStreamer::emitEventType(MCSymbolWasm *Sym) {
145   // Not needed.
146 }
147 void WebAssemblyTargetWasmStreamer::emitImportModule(MCSymbolWasm *Sym,
148                                                      StringRef ModuleName) {
149   Sym->setModuleName(ModuleName);
150 }
151