1 //===--- WebAssembly.cpp - WebAssembly ToolChain Implementation -*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "WebAssembly.h"
11 #include "CommonArgs.h"
12 #include "clang/Driver/Compilation.h"
13 #include "clang/Driver/Driver.h"
14 #include "clang/Driver/DriverDiagnostic.h"
15 #include "clang/Driver/Options.h"
16 #include "llvm/Option/ArgList.h"
18 using namespace clang::driver;
19 using namespace clang::driver::tools;
20 using namespace clang::driver::toolchains;
21 using namespace clang;
22 using namespace llvm::opt;
24 wasm::Linker::Linker(const ToolChain &TC)
25 : GnuTool("wasm::Linker", "lld", TC) {}
27 /// Following the conventions in https://wiki.debian.org/Multiarch/Tuples,
28 /// we remove the vendor field to form the multiarch triple.
29 static std::string getMultiarchTriple(const Driver &D,
30 const llvm::Triple &TargetTriple,
32 return (TargetTriple.getArchName() + "-" +
33 TargetTriple.getOSAndEnvironmentName()).str();
36 bool wasm::Linker::isLinkJob() const { return true; }
38 bool wasm::Linker::hasIntegratedCPP() const { return false; }
40 void wasm::Linker::ConstructJob(Compilation &C, const JobAction &JA,
41 const InputInfo &Output,
42 const InputInfoList &Inputs,
44 const char *LinkingOutput) const {
46 const ToolChain &ToolChain = getToolChain();
47 const char *Linker = Args.MakeArgString(ToolChain.GetLinkerPath());
48 ArgStringList CmdArgs;
50 if (Args.hasArg(options::OPT_s))
51 CmdArgs.push_back("--strip-all");
53 Args.AddAllArgs(CmdArgs, options::OPT_L);
54 Args.AddAllArgs(CmdArgs, options::OPT_u);
55 ToolChain.AddFilePathLibArgs(Args, CmdArgs);
57 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles))
58 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt1.o")));
60 AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
62 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
63 if (ToolChain.ShouldLinkCXXStdlib(Args))
64 ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
66 if (Args.hasArg(options::OPT_pthread))
67 CmdArgs.push_back("-lpthread");
69 CmdArgs.push_back("-lc");
70 AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args);
73 CmdArgs.push_back("-o");
74 CmdArgs.push_back(Output.getFilename());
76 C.addCommand(llvm::make_unique<Command>(JA, *this, Linker, CmdArgs, Inputs));
79 WebAssembly::WebAssembly(const Driver &D, const llvm::Triple &Triple,
80 const llvm::opt::ArgList &Args)
81 : ToolChain(D, Triple, Args) {
83 assert(Triple.isArch32Bit() != Triple.isArch64Bit());
85 getProgramPaths().push_back(getDriver().getInstalledDir());
87 if (getTriple().getOS() == llvm::Triple::UnknownOS) {
88 // Theoretically an "unknown" OS should mean no standard libraries, however
89 // it could also mean that a custom set of libraries is in use, so just add
90 // /lib to the search path. Disable multiarch in this case, to discourage
91 // paths containing "unknown" from acquiring meanings.
92 getFilePaths().push_back(getDriver().SysRoot + "/lib");
94 const std::string MultiarchTriple =
95 getMultiarchTriple(getDriver(), Triple, getDriver().SysRoot);
96 getFilePaths().push_back(getDriver().SysRoot + "/lib/" + MultiarchTriple);
100 bool WebAssembly::IsMathErrnoDefault() const { return false; }
102 bool WebAssembly::IsObjCNonFragileABIDefault() const { return true; }
104 bool WebAssembly::UseObjCMixedDispatch() const { return true; }
106 bool WebAssembly::isPICDefault() const { return false; }
108 bool WebAssembly::isPIEDefault() const { return false; }
110 bool WebAssembly::isPICDefaultForced() const { return false; }
112 bool WebAssembly::IsIntegratedAssemblerDefault() const { return true; }
114 bool WebAssembly::hasBlocksRuntime() const { return false; }
116 // TODO: Support profiling.
117 bool WebAssembly::SupportsProfiling() const { return false; }
119 bool WebAssembly::HasNativeLLVMSupport() const { return true; }
121 void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
122 ArgStringList &CC1Args,
123 Action::OffloadKind) const {
124 if (DriverArgs.hasFlag(clang::driver::options::OPT_fuse_init_array,
125 options::OPT_fno_use_init_array, true))
126 CC1Args.push_back("-fuse-init-array");
129 ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const {
130 return ToolChain::RLT_CompilerRT;
133 ToolChain::CXXStdlibType
134 WebAssembly::GetCXXStdlibType(const ArgList &Args) const {
135 if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
136 StringRef Value = A->getValue();
137 if (Value != "libc++")
138 getDriver().Diag(diag::err_drv_invalid_stdlib_name)
139 << A->getAsString(Args);
141 return ToolChain::CST_Libcxx;
144 void WebAssembly::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
145 ArgStringList &CC1Args) const {
146 if (!DriverArgs.hasArg(options::OPT_nostdinc)) {
147 if (getTriple().getOS() != llvm::Triple::UnknownOS) {
148 const std::string MultiarchTriple =
149 getMultiarchTriple(getDriver(), getTriple(), getDriver().SysRoot);
150 addSystemInclude(DriverArgs, CC1Args, getDriver().SysRoot + "/include/" + MultiarchTriple);
152 addSystemInclude(DriverArgs, CC1Args, getDriver().SysRoot + "/include");
156 void WebAssembly::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
157 ArgStringList &CC1Args) const {
158 if (!DriverArgs.hasArg(options::OPT_nostdlibinc) &&
159 !DriverArgs.hasArg(options::OPT_nostdincxx)) {
160 if (getTriple().getOS() != llvm::Triple::UnknownOS) {
161 const std::string MultiarchTriple =
162 getMultiarchTriple(getDriver(), getTriple(), getDriver().SysRoot);
163 addSystemInclude(DriverArgs, CC1Args,
164 getDriver().SysRoot + "/include/" + MultiarchTriple + "/c++/v1");
166 addSystemInclude(DriverArgs, CC1Args,
167 getDriver().SysRoot + "/include/c++/v1");
171 void WebAssembly::AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
172 llvm::opt::ArgStringList &CmdArgs) const {
174 switch (GetCXXStdlibType(Args)) {
175 case ToolChain::CST_Libcxx:
176 CmdArgs.push_back("-lc++");
177 CmdArgs.push_back("-lc++abi");
179 case ToolChain::CST_Libstdcxx:
180 llvm_unreachable("invalid stdlib name");
184 std::string WebAssembly::getThreadModel() const {
185 // The WebAssembly MVP does not yet support threads; for now, use the
186 // "single" threading model, which lowers atomics to non-atomic operations.
187 // When threading support is standardized and implemented in popular engines,
188 // this override should be removed.
192 Tool *WebAssembly::buildLinker() const {
193 return new tools::wasm::Linker(*this);