Extract LLVM compatibility code into its own translation unit

[ROCm/hip commit: 1bd837b4b1]

projects/hip/hipify-clang/src/LLVMCompat.cpp

@@ -0,0 +1,43 @@
+#include "LLVMCompat.h"
+
+namespace llcompat {
+
+void PrintStackTraceOnErrorSignal() {
+    // The signature of PrintStackTraceOnErrorSignal changed in llvm 3.9. We don't support
+    // anything older than 3.8, so let's specifically detect the one old version we support.
+#if (LLVM_VERSION_MAJOR == 3) && (LLVM_VERSION_MINOR == 8)
+    llvm::sys::PrintStackTraceOnErrorSignal();
+#else
+    llvm::sys::PrintStackTraceOnErrorSignal(clang::StringRef());
+#endif
+}
+
+ct::Replacements& getReplacements(ct::RefactoringTool& Tool, clang::StringRef file) {
+#if LLVM_VERSION_MAJOR > 3
+    // getReplacements() now returns a map from filename to Replacements - so create an entry
+    // for this source file and return a reference to it.
+    return Tool.getReplacements()[file];
+#else
+    return Tool.getReplacements();
+#endif
+}
+
+void insertReplacement(ct::Replacements& replacements, const ct::Replacement& rep) {
+#if LLVM_VERSION_MAJOR > 3
+    // New clang added error checking to Replacements, and *insists* that you explicitly check it.
+    llvm::Error e = replacements.add(rep);
+#else
+    // In older versions, it's literally an std::set<Replacement>
+    replacements.insert(rep);
+#endif
+}
+
+void EnterPreprocessorTokenStream(clang::Preprocessor& _pp, const clang::Token *start, size_t len, bool DisableMacroExpansion) {
+#if (LLVM_VERSION_MAJOR == 3) && (LLVM_VERSION_MINOR == 8)
+    _pp.EnterTokenStream(start, len, false, DisableMacroExpansion;
+#else
+    _pp.EnterTokenStream(clang::ArrayRef<clang::Token>{start, len}, DisableMacroExpansion);
+#endif
+}
+
+} // namespace llcompat