Makefile: Add CPP code coverage

Author: AbdealiLoKo

Makefile

@@ -48,11 +48,17 @@ export CXX = $(if $(shell which g++-6),g++-6,$(if $(shell which g++-mp-6),g++-mp
 endif
 
 export LDFLAGS= -pthread -lm $(ADD_LDFLAGS) $(DMLC_LDFLAGS) $(PLUGIN_LDFLAGS)
-export CFLAGS=  -std=c++0x -Wall -O3 -msse2  -Wno-unknown-pragmas -funroll-loops -Iinclude $(ADD_CFLAGS) $(PLUGIN_CFLAGS)
+export CFLAGS=  -std=c++0x -Wall -Wno-unknown-pragmas -Iinclude $(ADD_CFLAGS) $(PLUGIN_CFLAGS)
 CFLAGS += -I$(DMLC_CORE)/include -I$(RABIT)/include
 #java include path
 export JAVAINCFLAGS = -I${JAVA_HOME}/include -I./java
 
+ifeq ($(TEST_COVER), 1)
+	CFLAGS += -g -O0 -fprofile-arcs -ftest-coverage
+else
+	CFLAGS += -O3 -funroll-loops -msse2
+endif
+
 ifndef LINT_LANG
 	LINT_LANG= "all"
 endif
@@ -152,9 +158,14 @@ test: $(ALL_TEST)
 check: test
 	./tests/cpp/xgboost_test
 
+ifeq ($(TEST_COVER), 1)
+cover: check
+	gcov -pbcu $(COVER_OBJ)
+endif
+
 clean:
 	$(RM) -rf build build_plugin lib bin *~ */*~ */*/*~ */*/*/*~ */*.o */*/*.o */*/*/*.o xgboost
-	$(RM) -rf build_tests tests/cpp/xgboost_test
+	$(RM) -rf build_tests *.gcov tests/cpp/xgboost_test
 
 clean_all: clean
 	cd $(DMLC_CORE); $(MAKE) clean; cd $(ROOTDIR)

make/config.mk

@@ -47,6 +47,11 @@ LIB_RABIT = librabit.a
 # path to libjvm.so
 LIBJVM=$(JAVA_HOME)/jre/lib/amd64/server
 
+# whether to test with coverage measurement or not. (only used for `make cover`)
+# measured with gcov and html report generated with lcov if it is installed.
+# this disables optimization to ensure coverage information is correct
+TEST_COVER = 1
+
 # path to gtest library (only used when $BUILD_TEST=1)
 # there should be an include path in $GTEST_PATH/include and library in $GTEST_PATH/lib
 GTEST_PATH =

tests/cpp/xgboost_test.mk

@@ -11,6 +11,8 @@ UNITTEST_CFLAGS=$(CFLAGS)
 UNITTEST_LDFLAGS=$(LDFLAGS) -L$(GTEST_LIB) -lgtest
 UNITTEST_DEPS=lib/libxgboost.a $(DMLC_CORE)/libdmlc.a $(RABIT)/lib/$(LIB_RABIT)
 
+COVER_OBJ=$(patsubst %.o, %.gcda, $(ALL_OBJ)) $(patsubst %.o, %.gcda, $(UNITTEST_OBJ))
+
 $(UTEST_OBJ_ROOT)/%.o: $(UTEST_ROOT)/%.cc
 	@mkdir -p $(@D)
 	$(CXX) $(UNITTEST_CFLAGS) -I$(GTEST_INC) -o $@ -c $<