Allow setting the LLVM version from higher-level projects

Author: fabianbs

CMakeLists.txt

@@ -8,6 +8,10 @@ set(CMAKE_POLICY_DEFAULT_CMP0069 NEW)
 cmake_policy(SET CMP0077 NEW)
 set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
 
+# Allow overwriting cache variables of external projects from this CMakeLists file
+cmake_policy(SET CMP0126 NEW)
+set(CMAKE_POLICY_DEFAULT_CMP0126 NEW)
+
 # Allow portable use of CMAKE_VISIBILITY_INLINES_HIDDEN not only for shared libraries
 cmake_policy(SET CMP0063 NEW)
 set(CMAKE_POLICY_DEFAULT_CMP0063 NEW)
@@ -303,6 +307,9 @@ endif()
 option(USE_LLVM_FAT_LIB  "Link against libLLVM.so instead of the individual LLVM libraries if possible (default is OFF; always on if BUILD_SHARED_LIBS is ON)" OFF)
 
 # LLVM
+if (NOT PHASAR_LLVM_VERSION)
+  set(PHASAR_LLVM_VERSION 14)
+endif()
 include(add_llvm)
 add_llvm()
 

cmake/add_llvm.cmake

@@ -2,7 +2,7 @@ macro(add_llvm)
 
   if (NOT PHASAR_IN_TREE)
     # Only search for LLVM if we build out of tree
-    find_package(LLVM 14 REQUIRED CONFIG)
+    find_package(LLVM ${PHASAR_LLVM_VERSION} REQUIRED CONFIG)
     find_library(LLVM_LIBRARY NAMES LLVM PATHS ${LLVM_LIBRARY_DIRS} NO_DEFAULT_PATH)
 
     if(USE_LLVM_FAT_LIB AND ${LLVM_LIBRARY} STREQUAL "LLVM_LIBRARY-NOTFOUND")

lib/PhasarLLVM/DB/LLVMProjectIRDB.cpp

@@ -20,6 +20,21 @@
 
 namespace psr {
 
+static void setOpaquePointersForCtx(llvm::LLVMContext &Ctx, bool Enable) {
+#if LLVM_VERSION_MAJOR >= 15 && LLVM_VERSION_MAJOR < 17
+  if (!Enable) {
+    Ctx.setOpaquePointers(false);
+  }
+#elif LLVM_VERSION_MAJOR < 15
+  if (Enable) {
+    Ctx.enableOpaquePointers();
+  }
+#else // LLVM_VERSION_MAJOR >= 17
+#error                                                                         \
+    "Non-opaque pointers are not supported anymore. Refactor PhASAR to remove typed pointer support."
+#endif
+}
+
 std::unique_ptr<llvm::Module>
 LLVMProjectIRDB::getParsedIRModuleOrNull(llvm::MemoryBufferRef IRFileContent,
                                          llvm::LLVMContext &Ctx) noexcept {
@@ -63,9 +78,7 @@ LLVMProjectIRDB::getParsedIRModuleOrNull(const llvm::Twine &IRFileName,
 
 LLVMProjectIRDB::LLVMProjectIRDB(const llvm::Twine &IRFileName,
                                  bool EnableOpaquePointers) {
-  if (EnableOpaquePointers) {
-    Ctx.enableOpaquePointers();
-  }
+  setOpaquePointersForCtx(Ctx, EnableOpaquePointers);
   auto M = getParsedIRModuleOrNull(IRFileName, Ctx);
 
   if (!M) {
@@ -160,9 +173,7 @@ LLVMProjectIRDB::LLVMProjectIRDB(std::unique_ptr<llvm::Module> Mod,
 
 LLVMProjectIRDB::LLVMProjectIRDB(llvm::MemoryBufferRef Buf,
                                  bool EnableOpaquePointers) {
-  if (EnableOpaquePointers) {
-    Ctx.enableOpaquePointers();
-  }
+  setOpaquePointersForCtx(Ctx, EnableOpaquePointers);
   auto M = getParsedIRModuleOrNull(Buf, Ctx);
   if (!M) {
     return;