CPU: Hook PCH and debuginfo support to the build system

src/ngraph/CMakeLists.txt

@@ -115,6 +115,10 @@ if(LLVM_INCLUDE_DIR)
     set_source_files_properties(codegen/compiler.cpp PROPERTIES COMPILE_FLAGS "-fno-rtti")
     set_source_files_properties(codegen/compiler.cpp PROPERTIES COMPILE_DEFINITIONS
       "EIGEN_HEADERS_PATH=\"${EIGEN_INCLUDE_DIR}\";CLANG_BUILTIN_HEADERS_PATH=\"${LLVM_LIB_DIR}/clang/5.0.0/include\";NGRAPH_HEADERS_PATH=\"${NGRAPH_INCLUDE_PATH}\"")
+    set(CPU_ENABLE_PCH 0 CACHE STRING "Enable pre-compiled headers in the CPU backend")
+    set(CPU_ENABLE_DEBUGINFO 0 CACHE STRING "Enable debuginfo in the CPU backend")
+    set_source_files_properties(runtime/cpu/external_function.cpp PROPERTIES COMPILE_DEFINITIONS
+      "NGCPU_PCH=${CPU_ENABLE_PCH};NGCPU_DEBUGINFO=${CPU_ENABLE_DEBUGINFO}")
 endif()
 
 add_library(ngraph SHARED ${SRC})

src/ngraph/runtime/cpu/external_function.cpp

@@ -59,11 +59,6 @@
 #include "ngraph/runtime/cpu/external_function.hpp"
 #include "ngraph/runtime/utils.hpp"
 
-// TODO: Decide if we want to ship this or
-// just enable it for developer build-test cycles
-//#define NGCPU_PCH
-//#define NGCPU_DEBUGINFO
-
 using namespace std;
 using namespace ngraph::runtime::cpu;
 
@@ -249,11 +244,11 @@ extern "C" void __entrypoint(ngraph::runtime::cpu::CallFrame* call_frame,
 
     ngraph::codegen::execution_state estate;
 
-#if defined(NGCPU_PCH)
+#if NGCPU_PCH
     estate.enable_pch();
 #endif
 
-#if defined(NGCPU_DEBUGINFO)
+#if NGCPU_DEBUGINFO
     estate.enable_debuginfo();
 #endif