llvm-config.cpp revision 8033f6197c2cd7a71c9a725e49efaa402a17e707
1//===-- llvm-config.cpp - LLVM project configuration utility --------------===// 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// This tool encapsulates information about an LLVM project configuration for 11// use by other project's build environments (to determine installed path, 12// available features, required libraries, etc.). 13// 14// Note that although this tool *may* be used by some parts of LLVM's build 15// itself (i.e., the Makefiles use it to compute required libraries when linking 16// tools), this tool is primarily designed to support external projects. 17// 18//===----------------------------------------------------------------------===// 19 20#include "llvm/ADT/STLExtras.h" 21#include "llvm/ADT/StringMap.h" 22#include "llvm/ADT/StringRef.h" 23#include "llvm/ADT/Twine.h" 24#include "llvm/Config/config.h" 25#include "llvm/Config/llvm-config.h" 26#include "llvm/Support/FileSystem.h" 27#include "llvm/Support/Path.h" 28#include "llvm/Support/TargetRegistry.h" 29#include "llvm/Support/raw_ostream.h" 30#include <cstdlib> 31#include <set> 32#include <vector> 33 34using namespace llvm; 35 36// Include the build time variables we can report to the user. This is generated 37// at build time from the BuildVariables.inc.in file by the build system. 38#include "BuildVariables.inc" 39 40// Include the component table. This creates an array of struct 41// AvailableComponent entries, which record the component name, library name, 42// and required components for all of the available libraries. 43// 44// Not all components define a library, we also use "library groups" as a way to 45// create entries for pseudo groups like x86 or all-targets. 46#include "LibraryDependencies.inc" 47 48/// \brief Traverse a single component adding to the topological ordering in 49/// \arg RequiredLibs. 50/// 51/// \param Name - The component to traverse. 52/// \param ComponentMap - A prebuilt map of component names to descriptors. 53/// \param VisitedComponents [in] [out] - The set of already visited components. 54/// \param RequiredLibs [out] - The ordered list of required libraries. 55static void VisitComponent(StringRef Name, 56 const StringMap<AvailableComponent*> &ComponentMap, 57 std::set<AvailableComponent*> &VisitedComponents, 58 std::vector<StringRef> &RequiredLibs) { 59 // Lookup the component. 60 AvailableComponent *AC = ComponentMap.lookup(Name); 61 assert(AC && "Invalid component name!"); 62 63 // Add to the visited table. 64 if (!VisitedComponents.insert(AC).second) { 65 // We are done if the component has already been visited. 66 return; 67 } 68 69 // Otherwise, visit all the dependencies. 70 for (unsigned i = 0; AC->RequiredLibraries[i]; ++i) { 71 VisitComponent(AC->RequiredLibraries[i], ComponentMap, VisitedComponents, 72 RequiredLibs); 73 } 74 75 // Add to the required library list. 76 if (AC->Library) 77 RequiredLibs.push_back(AC->Library); 78} 79 80/// \brief Compute the list of required libraries for a given list of 81/// components, in an order suitable for passing to a linker (that is, libraries 82/// appear prior to their dependencies). 83/// 84/// \param Components - The names of the components to find libraries for. 85/// \param RequiredLibs [out] - On return, the ordered list of libraries that 86/// are required to link the given components. 87void ComputeLibsForComponents(const std::vector<StringRef> &Components, 88 std::vector<StringRef> &RequiredLibs) { 89 std::set<AvailableComponent*> VisitedComponents; 90 91 // Build a map of component names to information. 92 StringMap<AvailableComponent*> ComponentMap; 93 for (unsigned i = 0; i != array_lengthof(AvailableComponents); ++i) { 94 AvailableComponent *AC = &AvailableComponents[i]; 95 ComponentMap[AC->Name] = AC; 96 } 97 98 // Visit the components. 99 for (unsigned i = 0, e = Components.size(); i != e; ++i) { 100 // Users are allowed to provide mixed case component names. 101 std::string ComponentLower = Components[i].lower(); 102 103 // Validate that the user supplied a valid component name. 104 if (!ComponentMap.count(ComponentLower)) { 105 llvm::errs() << "llvm-config: unknown component name: " << Components[i] 106 << "\n"; 107 exit(1); 108 } 109 110 VisitComponent(ComponentLower, ComponentMap, VisitedComponents, 111 RequiredLibs); 112 } 113 114 // The list is now ordered with leafs first, we want the libraries to printed 115 // in the reverse order of dependency. 116 std::reverse(RequiredLibs.begin(), RequiredLibs.end()); 117} 118 119/* *** */ 120 121void usage() { 122 errs() << "\ 123usage: llvm-config <OPTION>... [<COMPONENT>...]\n\ 124\n\ 125Get various configuration information needed to compile programs which use\n\ 126LLVM. Typically called from 'configure' scripts. Examples:\n\ 127 llvm-config --cxxflags\n\ 128 llvm-config --ldflags\n\ 129 llvm-config --libs engine bcreader scalaropts\n\ 130\n\ 131Options:\n\ 132 --version Print LLVM version.\n\ 133 --prefix Print the installation prefix.\n\ 134 --src-root Print the source root LLVM was built from.\n\ 135 --obj-root Print the object root used to build LLVM.\n\ 136 --bindir Directory containing LLVM executables.\n\ 137 --includedir Directory containing LLVM headers.\n\ 138 --libdir Directory containing LLVM libraries.\n\ 139 --cppflags C preprocessor flags for files that include LLVM headers.\n\ 140 --cflags C compiler flags for files that include LLVM headers.\n\ 141 --cxxflags C++ compiler flags for files that include LLVM headers.\n\ 142 --ldflags Print Linker flags.\n\ 143 --libs Libraries needed to link against LLVM components.\n\ 144 --libnames Bare library names for in-tree builds.\n\ 145 --libfiles Fully qualified library filenames for makefile depends.\n\ 146 --components List of all possible components.\n\ 147 --targets-built List of all targets currently built.\n\ 148 --host-target Target triple used to configure LLVM.\n\ 149 --build-mode Print build mode of LLVM tree (e.g. Debug or Release).\n\ 150Typical components:\n\ 151 all All LLVM libraries (default).\n\ 152 backend Either a native backend or the C backend.\n\ 153 engine Either a native JIT or a bitcode interpreter.\n"; 154 exit(1); 155} 156 157/// \brief Compute the path to the main executable. 158llvm::sys::Path GetExecutablePath(const char *Argv0) { 159 // This just needs to be some symbol in the binary; C++ doesn't 160 // allow taking the address of ::main however. 161 void *P = (void*) (intptr_t) GetExecutablePath; 162 return llvm::sys::Path::GetMainExecutable(Argv0, P); 163} 164 165int main(int argc, char **argv) { 166 std::vector<StringRef> Components; 167 bool PrintLibs = false, PrintLibNames = false, PrintLibFiles = false; 168 bool HasAnyOption = false; 169 170 // llvm-config is designed to support being run both from a development tree 171 // and from an installed path. We try and auto-detect which case we are in so 172 // that we can report the correct information when run from a development 173 // tree. 174 bool IsInDevelopmentTree, DevelopmentTreeLayoutIsCMakeStyle; 175 llvm::SmallString<256> CurrentPath(GetExecutablePath(argv[0]).str()); 176 std::string CurrentExecPrefix; 177 std::string ActiveObjRoot; 178 179 // Create an absolute path, and pop up one directory (we expect to be inside a 180 // bin dir). 181 sys::fs::make_absolute(CurrentPath); 182 CurrentExecPrefix = sys::path::parent_path( 183 sys::path::parent_path(CurrentPath)).str(); 184 185 // Check to see if we are inside a development tree by comparing to possible 186 // locations (prefix style or CMake style). This could be wrong in the face of 187 // symbolic links, but is good enough. 188 if (CurrentExecPrefix == std::string(LLVM_OBJ_ROOT) + "/" + LLVM_BUILDMODE) { 189 IsInDevelopmentTree = true; 190 DevelopmentTreeLayoutIsCMakeStyle = false; 191 192 // If we are in a development tree, then check if we are in a BuildTools 193 // directory. This indicates we are built for the build triple, but we 194 // always want to provide information for the host triple. 195 if (sys::path::filename(LLVM_OBJ_ROOT) == "BuildTools") { 196 ActiveObjRoot = sys::path::parent_path(LLVM_OBJ_ROOT); 197 } else { 198 ActiveObjRoot = LLVM_OBJ_ROOT; 199 } 200 } else if (CurrentExecPrefix == std::string(LLVM_OBJ_ROOT) + "/bin") { 201 IsInDevelopmentTree = true; 202 DevelopmentTreeLayoutIsCMakeStyle = true; 203 ActiveObjRoot = LLVM_OBJ_ROOT; 204 } else { 205 IsInDevelopmentTree = false; 206 } 207 208 // Compute various directory locations based on the derived location 209 // information. 210 std::string ActivePrefix, ActiveBinDir, ActiveIncludeDir, ActiveLibDir; 211 std::string ActiveIncludeOption; 212 if (IsInDevelopmentTree) { 213 ActiveIncludeDir = std::string(LLVM_SRC_ROOT) + "/include"; 214 ActivePrefix = CurrentExecPrefix; 215 216 // CMake organizes the products differently than a normal prefix style 217 // layout. 218 if (DevelopmentTreeLayoutIsCMakeStyle) { 219 ActiveBinDir = ActiveObjRoot + "/bin/" + LLVM_BUILDMODE; 220 ActiveLibDir = ActiveObjRoot + "/lib/" + LLVM_BUILDMODE; 221 } else { 222 ActiveBinDir = ActiveObjRoot + "/" + LLVM_BUILDMODE + "/bin"; 223 ActiveLibDir = ActiveObjRoot + "/" + LLVM_BUILDMODE + "/lib"; 224 } 225 226 // We need to include files from both the source and object trees. 227 ActiveIncludeOption = ("-I" + ActiveIncludeDir + " " + 228 "-I" + ActiveObjRoot + "/include"); 229 } else { 230 ActivePrefix = CurrentExecPrefix; 231 ActiveIncludeDir = ActivePrefix + "/include"; 232 ActiveBinDir = ActivePrefix + "/bin"; 233 ActiveLibDir = ActivePrefix + "/lib"; 234 ActiveIncludeOption = "-I" + ActiveIncludeDir; 235 } 236 237 raw_ostream &OS = outs(); 238 for (int i = 1; i != argc; ++i) { 239 StringRef Arg = argv[i]; 240 241 if (Arg.startswith("-")) { 242 HasAnyOption = true; 243 if (Arg == "--version") { 244 OS << PACKAGE_VERSION << '\n'; 245 } else if (Arg == "--prefix") { 246 OS << ActivePrefix << '\n'; 247 } else if (Arg == "--bindir") { 248 OS << ActiveBinDir << '\n'; 249 } else if (Arg == "--includedir") { 250 OS << ActiveIncludeDir << '\n'; 251 } else if (Arg == "--libdir") { 252 OS << ActiveLibDir << '\n'; 253 } else if (Arg == "--cppflags") { 254 OS << ActiveIncludeOption << ' ' << LLVM_CPPFLAGS << '\n'; 255 } else if (Arg == "--cflags") { 256 OS << ActiveIncludeOption << ' ' << LLVM_CFLAGS << '\n'; 257 } else if (Arg == "--cxxflags") { 258 OS << ActiveIncludeOption << ' ' << LLVM_CXXFLAGS << '\n'; 259 } else if (Arg == "--ldflags") { 260 OS << "-L" << ActiveLibDir << ' ' << LLVM_LDFLAGS 261 << ' ' << LLVM_SYSTEM_LIBS << '\n'; 262 } else if (Arg == "--libs") { 263 PrintLibs = true; 264 } else if (Arg == "--libnames") { 265 PrintLibNames = true; 266 } else if (Arg == "--libfiles") { 267 PrintLibFiles = true; 268 } else if (Arg == "--components") { 269 for (unsigned j = 0; j != array_lengthof(AvailableComponents); ++j) { 270 OS << ' '; 271 OS << AvailableComponents[j].Name; 272 } 273 OS << '\n'; 274 } else if (Arg == "--targets-built") { 275 bool First = true; 276 for (TargetRegistry::iterator I = TargetRegistry::begin(), 277 E = TargetRegistry::end(); I != E; First = false, ++I) { 278 if (!First) 279 OS << ' '; 280 OS << I->getName(); 281 } 282 OS << '\n'; 283 } else if (Arg == "--host-target") { 284 OS << LLVM_DEFAULT_TARGET_TRIPLE << '\n'; 285 } else if (Arg == "--build-mode") { 286 OS << LLVM_BUILDMODE << '\n'; 287 } else if (Arg == "--obj-root") { 288 OS << LLVM_OBJ_ROOT << '\n'; 289 } else if (Arg == "--src-root") { 290 OS << LLVM_SRC_ROOT << '\n'; 291 } else { 292 usage(); 293 } 294 } else { 295 Components.push_back(Arg); 296 } 297 } 298 299 if (!HasAnyOption) 300 usage(); 301 302 if (PrintLibs || PrintLibNames || PrintLibFiles) { 303 // If no components were specified, default to "all". 304 if (Components.empty()) 305 Components.push_back("all"); 306 307 // Construct the list of all the required libraries. 308 std::vector<StringRef> RequiredLibs; 309 ComputeLibsForComponents(Components, RequiredLibs); 310 311 for (unsigned i = 0, e = RequiredLibs.size(); i != e; ++i) { 312 StringRef Lib = RequiredLibs[i]; 313 if (i) 314 OS << ' '; 315 316 if (PrintLibNames) { 317 OS << Lib; 318 } else if (PrintLibFiles) { 319 OS << ActiveLibDir << '/' << Lib; 320 } else if (PrintLibs) { 321 // If this is a typical library name, include it using -l. 322 if (Lib.startswith("lib") && Lib.endswith(".a")) { 323 OS << "-l" << Lib.slice(3, Lib.size()-2); 324 continue; 325 } 326 327 // Otherwise, print the full path. 328 OS << ActiveLibDir << '/' << Lib; 329 } 330 } 331 OS << '\n'; 332 } else if (!Components.empty()) { 333 errs() << "llvm-config: error: components given, but unused\n\n"; 334 usage(); 335 } 336 337 return 0; 338} 339