1 files changed, 96 insertions, 0 deletions
diff --git a/cmake/find_bitcode_compiler.cmake b/cmake/find_bitcode_compiler.cmake
new file mode 100644
index 00000000..615931f3
--- /dev/null
+++ b/cmake/find_bitcode_compiler.cmake
@@ -0,0 +1,96 @@
+#===------------------------------------------------------------------------===#
+#
+#                     The KLEE Symbolic Virtual Machine
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+#===------------------------------------------------------------------------===#
+#
+# This file tries to find compilers to build LLVM bitcode.
+# It is implicitly dependent on `find_llvm.cmake` already being run in the
+# same scope.
+#
+#===------------------------------------------------------------------------===#
+
+message(STATUS "Looking for bitcode compilers")
+
+find_program(
+  LLVMCC
+  NAMES "clang-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}" "clang" "llvm-gcc"
+   # Give the LLVM tools directory higher priority than the system directory.
+  HINTS "${LLVM_TOOLS_BINARY_DIR}"
+)
+if (LLVMCC)
+  message(STATUS "Found ${LLVMCC}")
+else()
+  message(FATAL_ERROR "Failed to find C bitcode compiler")
+endif()
+
+find_program(
+  LLVMCXX
+  NAMES "clang++-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}" "clang++" "llvm-g++"
+   # Give the LLVM tools directory higher priority than the system directory.
+  HINTS "${LLVM_TOOLS_BINARY_DIR}"
+)
+if (LLVMCXX)
+  message(STATUS "Found ${LLVMCXX}")
+else()
+  message(FATAL_ERROR "Failed to find C++ bitcode compiler")
+endif()
+
+# Check `llvm-dis` is available
+set(LLVM_DIS_TOOL "${LLVM_TOOLS_BINARY_DIR}/llvm-dis")
+if (NOT EXISTS "${LLVM_DIS_TOOL}")
+  message(FATAL_ERROR
+    "The llvm-dis tool cannot be found at \"${LLVM_DIS_TOOL}\"")
+endif()
+
+# Test compiler
+function(test_bitcode_compiler COMPILER SRC_EXT)
+  message(STATUS "Testing bitcode compiler ${COMPILER}")
+  set(SRC_FILE "${CMAKE_BINARY_DIR}/test_bitcode_compiler.${SRC_EXT}")
+  file(WRITE "${SRC_FILE}" "int main(int argc, char** argv) { return 0;}")
+  set(BC_FILE "${SRC_FILE}.bc")
+  execute_process(
+    COMMAND
+      "${COMPILER}"
+      "-c"
+      "-emit-llvm"
+      "-o" "${BC_FILE}"
+      "${SRC_FILE}"
+    RESULT_VARIABLE COMPILE_INVOKE_EXIT_CODE
+  )
+  if ("${COMPILE_INVOKE_EXIT_CODE}" EQUAL 0)
+    message(STATUS "Compile success")
+  else()
+    message(FATAL_ERROR "Compilation failed")
+  endif()
+
+  message(STATUS "Checking compatibility with LLVM ${LLVM_PACKAGE_VERSION}")
+  # Check if the LLVM version we are using is compatible
+  # with this compiler by invoking the `llvm-dis` tool
+  # on the generated bitcode.
+  set(LL_FILE "${SRC_FILE}.ll")
+  execute_process(
+    COMMAND
+      "${LLVM_DIS_TOOL}"
+      "-o" "${LL_FILE}"
+      "${BC_FILE}"
+    RESULT_VARIABLE LLVM_DIS_INVOKE_EXIT_CODE
+  )
+  if ("${LLVM_DIS_INVOKE_EXIT_CODE}" EQUAL 0)
+    message(STATUS "\"${COMPILER}\" is compatible")
+  else()
+    message(FATAL_ERROR "\"${COMPILER}\" is not compatible with LLVM ${LLVM_PACKAGE_VERSION}")
+  endif()
+
+  # Remove temporary files. It's okay to not remove these on failure
+  # as they will be useful for developer debugging.
+  file(REMOVE "${SRC_FILE}")
+  file(REMOVE "${BC_FILE}")
+  file(REMOVE "${LL_FILE}")
+endfunction()
+
+test_bitcode_compiler("${LLVMCC}" "c")
+test_bitcode_compiler("${LLVMCXX}" "cxx")