1 //===--- WebAssembly.cpp - WebAssembly ToolChain Implementation -*- 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 #include "WebAssembly.h" 10 #include "CommonArgs.h" 11 #include "clang/Config/config.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/Support/FileSystem.h" 17 #include "llvm/Support/Path.h" 18 #include "llvm/Option/ArgList.h" 19 20 using namespace clang::driver; 21 using namespace clang::driver::tools; 22 using namespace clang::driver::toolchains; 23 using namespace clang; 24 using namespace llvm::opt; 25 26 /// Following the conventions in https://wiki.debian.org/Multiarch/Tuples, 27 /// we remove the vendor field to form the multiarch triple. 28 static std::string getMultiarchTriple(const Driver &D, 29 const llvm::Triple &TargetTriple, 30 StringRef SysRoot) { 31 return (TargetTriple.getArchName() + "-" + 32 TargetTriple.getOSAndEnvironmentName()).str(); 33 } 34 35 std::string wasm::Linker::getLinkerPath(const ArgList &Args) const { 36 const ToolChain &ToolChain = getToolChain(); 37 if (const Arg* A = Args.getLastArg(options::OPT_fuse_ld_EQ)) { 38 StringRef UseLinker = A->getValue(); 39 if (!UseLinker.empty()) { 40 if (llvm::sys::path::is_absolute(UseLinker) && 41 llvm::sys::fs::can_execute(UseLinker)) 42 return UseLinker; 43 44 // Accept 'lld', and 'ld' as aliases for the default linker 45 if (UseLinker != "lld" && UseLinker != "ld") 46 ToolChain.getDriver().Diag(diag::err_drv_invalid_linker_name) 47 << A->getAsString(Args); 48 } 49 } 50 51 return ToolChain.GetProgramPath(ToolChain.getDefaultLinker()); 52 } 53 54 void wasm::Linker::ConstructJob(Compilation &C, const JobAction &JA, 55 const InputInfo &Output, 56 const InputInfoList &Inputs, 57 const ArgList &Args, 58 const char *LinkingOutput) const { 59 60 const ToolChain &ToolChain = getToolChain(); 61 const char *Linker = Args.MakeArgString(getLinkerPath(Args)); 62 ArgStringList CmdArgs; 63 64 if (Args.hasArg(options::OPT_s)) 65 CmdArgs.push_back("--strip-all"); 66 67 Args.AddAllArgs(CmdArgs, options::OPT_L); 68 Args.AddAllArgs(CmdArgs, options::OPT_u); 69 ToolChain.AddFilePathLibArgs(Args, CmdArgs); 70 71 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) 72 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt1.o"))); 73 74 AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA); 75 76 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) { 77 if (ToolChain.ShouldLinkCXXStdlib(Args)) 78 ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs); 79 80 if (Args.hasArg(options::OPT_pthread)) { 81 CmdArgs.push_back("-lpthread"); 82 CmdArgs.push_back("--shared-memory"); 83 } 84 85 CmdArgs.push_back("-lc"); 86 AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args); 87 } 88 89 CmdArgs.push_back("-o"); 90 CmdArgs.push_back(Output.getFilename()); 91 92 C.addCommand(llvm::make_unique<Command>(JA, *this, Linker, CmdArgs, Inputs)); 93 } 94 95 WebAssembly::WebAssembly(const Driver &D, const llvm::Triple &Triple, 96 const llvm::opt::ArgList &Args) 97 : ToolChain(D, Triple, Args) { 98 99 assert(Triple.isArch32Bit() != Triple.isArch64Bit()); 100 101 getProgramPaths().push_back(getDriver().getInstalledDir()); 102 103 if (getTriple().getOS() == llvm::Triple::UnknownOS) { 104 // Theoretically an "unknown" OS should mean no standard libraries, however 105 // it could also mean that a custom set of libraries is in use, so just add 106 // /lib to the search path. Disable multiarch in this case, to discourage 107 // paths containing "unknown" from acquiring meanings. 108 getFilePaths().push_back(getDriver().SysRoot + "/lib"); 109 } else { 110 const std::string MultiarchTriple = 111 getMultiarchTriple(getDriver(), Triple, getDriver().SysRoot); 112 getFilePaths().push_back(getDriver().SysRoot + "/lib/" + MultiarchTriple); 113 } 114 } 115 116 bool WebAssembly::IsMathErrnoDefault() const { return false; } 117 118 bool WebAssembly::IsObjCNonFragileABIDefault() const { return true; } 119 120 bool WebAssembly::UseObjCMixedDispatch() const { return true; } 121 122 bool WebAssembly::isPICDefault() const { return false; } 123 124 bool WebAssembly::isPIEDefault() const { return false; } 125 126 bool WebAssembly::isPICDefaultForced() const { return false; } 127 128 bool WebAssembly::IsIntegratedAssemblerDefault() const { return true; } 129 130 bool WebAssembly::hasBlocksRuntime() const { return false; } 131 132 // TODO: Support profiling. 133 bool WebAssembly::SupportsProfiling() const { return false; } 134 135 bool WebAssembly::HasNativeLLVMSupport() const { return true; } 136 137 void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs, 138 ArgStringList &CC1Args, 139 Action::OffloadKind) const { 140 if (DriverArgs.hasFlag(clang::driver::options::OPT_fuse_init_array, 141 options::OPT_fno_use_init_array, true)) 142 CC1Args.push_back("-fuse-init-array"); 143 144 // '-pthread' implies atomics, bulk-memory, and mutable-globals 145 if (DriverArgs.hasFlag(options::OPT_pthread, options::OPT_no_pthread, 146 false)) { 147 if (DriverArgs.hasFlag(options::OPT_mno_atomics, options::OPT_matomics, 148 false)) 149 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 150 << "-pthread" 151 << "-mno-atomics"; 152 if (DriverArgs.hasFlag(options::OPT_mno_bulk_memory, 153 options::OPT_mbulk_memory, false)) 154 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 155 << "-pthread" 156 << "-mno-bulk-memory"; 157 if (DriverArgs.hasFlag(options::OPT_mno_mutable_globals, 158 options::OPT_mmutable_globals, false)) 159 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 160 << "-pthread" 161 << "-mno-mutable-globals"; 162 CC1Args.push_back("-target-feature"); 163 CC1Args.push_back("+atomics"); 164 CC1Args.push_back("-target-feature"); 165 CC1Args.push_back("+bulk-memory"); 166 CC1Args.push_back("-target-feature"); 167 CC1Args.push_back("+mutable-globals"); 168 } 169 } 170 171 ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const { 172 return ToolChain::RLT_CompilerRT; 173 } 174 175 ToolChain::CXXStdlibType 176 WebAssembly::GetCXXStdlibType(const ArgList &Args) const { 177 if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) { 178 StringRef Value = A->getValue(); 179 if (Value != "libc++") 180 getDriver().Diag(diag::err_drv_invalid_stdlib_name) 181 << A->getAsString(Args); 182 } 183 return ToolChain::CST_Libcxx; 184 } 185 186 void WebAssembly::AddClangSystemIncludeArgs(const ArgList &DriverArgs, 187 ArgStringList &CC1Args) const { 188 if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc)) 189 return; 190 191 const Driver &D = getDriver(); 192 193 if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) { 194 SmallString<128> P(D.ResourceDir); 195 llvm::sys::path::append(P, "include"); 196 addSystemInclude(DriverArgs, CC1Args, P); 197 } 198 199 if (DriverArgs.hasArg(options::OPT_nostdlibinc)) 200 return; 201 202 // Check for configure-time C include directories. 203 StringRef CIncludeDirs(C_INCLUDE_DIRS); 204 if (CIncludeDirs != "") { 205 SmallVector<StringRef, 5> dirs; 206 CIncludeDirs.split(dirs, ":"); 207 for (StringRef dir : dirs) { 208 StringRef Prefix = 209 llvm::sys::path::is_absolute(dir) ? StringRef(D.SysRoot) : ""; 210 addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir); 211 } 212 return; 213 } 214 215 if (getTriple().getOS() != llvm::Triple::UnknownOS) { 216 const std::string MultiarchTriple = 217 getMultiarchTriple(D, getTriple(), D.SysRoot); 218 addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include/" + MultiarchTriple); 219 } 220 addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include"); 221 } 222 223 void WebAssembly::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs, 224 ArgStringList &CC1Args) const { 225 if (!DriverArgs.hasArg(options::OPT_nostdlibinc) && 226 !DriverArgs.hasArg(options::OPT_nostdincxx)) { 227 if (getTriple().getOS() != llvm::Triple::UnknownOS) { 228 const std::string MultiarchTriple = 229 getMultiarchTriple(getDriver(), getTriple(), getDriver().SysRoot); 230 addSystemInclude(DriverArgs, CC1Args, 231 getDriver().SysRoot + "/include/" + MultiarchTriple + 232 "/c++/v1"); 233 } 234 addSystemInclude(DriverArgs, CC1Args, 235 getDriver().SysRoot + "/include/c++/v1"); 236 } 237 } 238 239 void WebAssembly::AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args, 240 llvm::opt::ArgStringList &CmdArgs) const { 241 242 switch (GetCXXStdlibType(Args)) { 243 case ToolChain::CST_Libcxx: 244 CmdArgs.push_back("-lc++"); 245 CmdArgs.push_back("-lc++abi"); 246 break; 247 case ToolChain::CST_Libstdcxx: 248 llvm_unreachable("invalid stdlib name"); 249 } 250 } 251 252 SanitizerMask WebAssembly::getSupportedSanitizers() const { 253 SanitizerMask Res = ToolChain::getSupportedSanitizers(); 254 if (getTriple().isOSEmscripten()) { 255 Res |= SanitizerKind::Vptr | SanitizerKind::Leak | SanitizerKind::Address; 256 } 257 return Res; 258 } 259 260 Tool *WebAssembly::buildLinker() const { 261 return new tools::wasm::Linker(*this); 262 } 263