[Frontend] Use the swift_static directory when appropriate.

We should be using `/usr/lib/swift_static` and not `/usr/lib/swift`
when we're using the static resource directory.

rdar://123506588

Author: al45tair

lib/Frontend/CompilerInvocation.cpp

@@ -186,8 +186,9 @@ void CompilerInvocation::setDefaultBlocklistsIfNecessary() {
 }
 
 static void updateRuntimeLibraryPaths(SearchPathOptions &SearchPathOpts,
-                                      LangOptions &LangOpts) {
-  llvm::Triple &Triple = LangOpts.Target;
+                                      const FrontendOptions &FrontendOpts,
+                                      const LangOptions &LangOpts) {
+  const llvm::Triple &Triple = LangOpts.Target;
   llvm::SmallString<128> LibPath(SearchPathOpts.RuntimeResourcePath);
 
   StringRef LibSubDir = getPlatformNameForTriple(Triple);
@@ -220,15 +221,18 @@ static void updateRuntimeLibraryPaths(SearchPathOptions &SearchPathOpts,
   }
 
   if (!SearchPathOpts.getSDKPath().empty()) {
+    const char *swiftDir = FrontendOpts.UseSharedResourceFolder
+      ? "swift" : "swift_static";
+
     if (tripleIsMacCatalystEnvironment(Triple)) {
       LibPath = SearchPathOpts.getSDKPath();
       llvm::sys::path::append(LibPath, "System", "iOSSupport");
-      llvm::sys::path::append(LibPath, "usr", "lib", "swift");
+      llvm::sys::path::append(LibPath, "usr", "lib", swiftDir);
       RuntimeLibraryImportPaths.push_back(std::string(LibPath.str()));
     }
 
     LibPath = SearchPathOpts.getSDKPath();
-    llvm::sys::path::append(LibPath, "usr", "lib", "swift");
+    llvm::sys::path::append(LibPath, "usr", "lib", swiftDir);
     if (!Triple.isOSDarwin()) {
       // Use the non-architecture suffixed form with directory-layout
       // swiftmodules.
@@ -298,7 +302,7 @@ setBridgingHeaderFromFrontendOptions(ClangImporterOptions &ImporterOpts,
 
 void CompilerInvocation::setRuntimeResourcePath(StringRef Path) {
   SearchPathOpts.RuntimeResourcePath = Path.str();
-  updateRuntimeLibraryPaths(SearchPathOpts, LangOpts);
+  updateRuntimeLibraryPaths(SearchPathOpts, FrontendOpts, LangOpts);
 }
 
 void CompilerInvocation::setTargetTriple(StringRef Triple) {
@@ -307,12 +311,12 @@ void CompilerInvocation::setTargetTriple(StringRef Triple) {
 
 void CompilerInvocation::setTargetTriple(const llvm::Triple &Triple) {
   LangOpts.setTarget(Triple);
-  updateRuntimeLibraryPaths(SearchPathOpts, LangOpts);
+  updateRuntimeLibraryPaths(SearchPathOpts, FrontendOpts, LangOpts);
 }
 
 void CompilerInvocation::setSDKPath(const std::string &Path) {
   SearchPathOpts.setSDKPath(Path);
-  updateRuntimeLibraryPaths(SearchPathOpts, LangOpts);
+  updateRuntimeLibraryPaths(SearchPathOpts, FrontendOpts, LangOpts);
 }
 
 bool CompilerInvocation::setModuleAliasMap(std::vector<std::string> args,
@@ -3260,7 +3264,7 @@ bool CompilerInvocation::parseArgs(
     return true;
   }
 
-  updateRuntimeLibraryPaths(SearchPathOpts, LangOpts);
+  updateRuntimeLibraryPaths(SearchPathOpts, FrontendOpts, LangOpts);
   setDefaultPrebuiltCacheIfNecessary();
   setDefaultBlocklistsIfNecessary();