[Driver] Update handling of c++ and runtime directories

This is a follow up to r361432 and r361504 which addresses issues
introduced by those changes. Specifically, it avoids duplicating
file and runtime paths in case when the effective triple is the
same as the cannonical one. Furthermore, it fixes the broken multilib
setup in the Fuchsia driver and deduplicates some of the code.

Differential Revision: https://reviews.llvm.org/D62442

llvm-svn: 361709

1 files changed, 41 insertions, 24 deletions

diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 08d1ebb..01fb818 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -73,29 +73,13 @@ ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
                      const ArgList &Args)
     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)) {
-  SmallString<128> P;
-
   if (D.CCCIsCXX()) {
-    P.assign(D.Dir);
-    llvm::sys::path::append(P, "..", "lib", D.getTargetTriple(), "c++");
-    if (getVFS().exists(P))
-      getLibraryPaths().push_back(P.str());
-
-    P.assign(D.Dir);
-    llvm::sys::path::append(P, "..", "lib", Triple.str(), "c++");
-    if (getVFS().exists(P))
-      getLibraryPaths().push_back(P.str());
+    if (auto CXXStdlibPath = getCXXStdlibPath())
+      getFilePaths().push_back(*CXXStdlibPath);
   }
 
-  P.assign(D.ResourceDir);
-  llvm::sys::path::append(P, D.getTargetTriple(), "lib");
-  if (getVFS().exists(P))
-    getLibraryPaths().push_back(P.str());
-
-  P.assign(D.ResourceDir);
-  llvm::sys::path::append(P, Triple.str(), "lib");
-  if (getVFS().exists(P))
-    getLibraryPaths().push_back(P.str());
+  if (auto RuntimePath = getRuntimePath())
+    getLibraryPaths().push_back(*RuntimePath);
 
   std::string CandidateLibPath = getArchSpecificLibPath();
   if (getVFS().exists(CandidateLibPath))
@@ -421,6 +405,43 @@ const char *ToolChain::getCompilerRTArgString(const llvm::opt::ArgList &Args,
   return Args.MakeArgString(getCompilerRT(Args, Component, Type));
 }
 
+
+Optional<std::string> ToolChain::getRuntimePath() const {
+  SmallString<128> P;
+
+  // First try the triple passed to driver as --target=<triple>.
+  P.assign(D.ResourceDir);
+  llvm::sys::path::append(P, D.getTargetTriple(), "lib");
+  if (getVFS().exists(P))
+    return llvm::Optional<std::string>(P.str());
+
+  // Second try the normalized triple.
+  P.assign(D.ResourceDir);
+  llvm::sys::path::append(P, Triple.str(), "lib");
+  if (getVFS().exists(P))
+    return llvm::Optional<std::string>(P.str());
+
+  return None;
+}
+
+Optional<std::string> ToolChain::getCXXStdlibPath() const {
+  SmallString<128> P;
+
+  // First try the triple passed to driver as --target=<triple>.
+  P.assign(D.Dir);
+  llvm::sys::path::append(P, "..", "lib", D.getTargetTriple(), "c++");
+  if (getVFS().exists(P))
+    return llvm::Optional<std::string>(P.str());
+
+  // Second try the normalized triple.
+  P.assign(D.Dir);
+  llvm::sys::path::append(P, "..", "lib", Triple.str(), "c++");
+  if (getVFS().exists(P))
+    return llvm::Optional<std::string>(P.str());
+
+  return None;
+}
+
 std::string ToolChain::getArchSpecificLibPath() const {
   SmallString<128> Path(getDriver().ResourceDir);
   llvm::sys::path::append(Path, "lib", getOSLibName(),
@@ -833,10 +854,6 @@ void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
 
 void ToolChain::AddFilePathLibArgs(const ArgList &Args,
                                    ArgStringList &CmdArgs) const {
-  for (const auto &LibPath : getLibraryPaths())
-    if(LibPath.length() > 0)
-      CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + LibPath));
-
   for (const auto &LibPath : getFilePaths())
     if(LibPath.length() > 0)
       CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + LibPath));