[llvm-config] Add --cmakedir to obtain CMake module location

Add a --cmakedir option to llvm-config that returns the correct path to
built/installed CMake modules (i.e. lib/cmake/llvm). This is mostly
intended as a convenience option for stand-alone builds of other LLVM
projects that frequently reconstruct LLVM_CMAKE_PATH after querying
llvm-config.

Differential Revision: https://reviews.llvm.org/D26894

llvm-svn: 291218

tools/llvm-config/llvm-config.cpp

@@ -196,6 +196,7 @@ Options:\n\
   --bindir          Directory containing LLVM executables.\n\
   --includedir      Directory containing LLVM headers.\n\
   --libdir          Directory containing LLVM libraries.\n\
+  --cmakedir        Directory containing LLVM cmake modules.\n\
   --cppflags        C preprocessor flags for files that include LLVM headers.\n\
   --cflags          C compiler flags for files that include LLVM headers.\n\
   --cxxflags        C++ compiler flags for files that include LLVM headers.\n\
@@ -302,7 +303,8 @@ int main(int argc, char **argv) {
 
   // Compute various directory locations based on the derived location
   // information.
-  std::string ActivePrefix, ActiveBinDir, ActiveIncludeDir, ActiveLibDir;
+  std::string ActivePrefix, ActiveBinDir, ActiveIncludeDir, ActiveLibDir,
+              ActiveCMakeDir;
   std::string ActiveIncludeOption;
   if (IsInDevelopmentTree) {
     ActiveIncludeDir = std::string(LLVM_SRC_ROOT) + "/include";
@@ -314,12 +316,14 @@ int main(int argc, char **argv) {
     case CMakeStyle:
       ActiveBinDir = ActiveObjRoot + "/bin";
       ActiveLibDir = ActiveObjRoot + "/lib" + LLVM_LIBDIR_SUFFIX;
+      ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
       break;
     case CMakeBuildModeStyle:
       ActivePrefix = ActiveObjRoot;
       ActiveBinDir = ActiveObjRoot + "/bin/" + build_mode;
       ActiveLibDir =
           ActiveObjRoot + "/lib" + LLVM_LIBDIR_SUFFIX + "/" + build_mode;
+      ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
       break;
     }
 
@@ -331,6 +335,7 @@ int main(int argc, char **argv) {
     ActiveIncludeDir = ActivePrefix + "/include";
     ActiveBinDir = ActivePrefix + "/bin";
     ActiveLibDir = ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX;
+    ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
     ActiveIncludeOption = "-I" + ActiveIncludeDir;
   }
 
@@ -357,6 +362,7 @@ int main(int argc, char **argv) {
       std::replace(ActivePrefix.begin(), ActivePrefix.end(), '/', '\\');
       std::replace(ActiveBinDir.begin(), ActiveBinDir.end(), '/', '\\');
       std::replace(ActiveLibDir.begin(), ActiveLibDir.end(), '/', '\\');
+      std::replace(ActiveCMakeDir.begin(), ActiveCMakeDir.end(), '/', '\\');
       std::replace(ActiveIncludeOption.begin(), ActiveIncludeOption.end(), '/',
                    '\\');
     }
@@ -475,6 +481,8 @@ int main(int argc, char **argv) {
         OS << ActiveIncludeDir << '\n';
       } else if (Arg == "--libdir") {
         OS << ActiveLibDir << '\n';
+      } else if (Arg == "--cmakedir") {
+        OS << ActiveCMakeDir << '\n';
       } else if (Arg == "--cppflags") {
         OS << ActiveIncludeOption << ' ' << LLVM_CPPFLAGS << '\n';
       } else if (Arg == "--cflags") {