[frontend] Put CompilerInvocation implementation into its own file.

Swift SVN r7464

lib/Frontend/CompilerInvocation.cpp

@@ -0,0 +1,28 @@
+//===-- CompilerInvocation.cpp - CompilerInvocation methods ---------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/Frontend/Frontend.h"
+#include "llvm/Support/Path.h"
+
+using namespace swift;
+
+swift::CompilerInvocation::CompilerInvocation() {
+  TargetTriple = llvm::sys::getDefaultTargetTriple();
+}
+
+void CompilerInvocation::setMainExecutablePath(StringRef Path) {
+  llvm::SmallString<128> LibPath(Path);
+  llvm::sys::path::remove_filename(LibPath); // Remove /swift
+  llvm::sys::path::remove_filename(LibPath); // Remove /bin
+  llvm::sys::path::append(LibPath, "lib", "swift");
+  setRuntimeIncludePath(LibPath.str());
+}