coreboot-kgpe-d16/tests/Makefile.inc
Julius Werner ab91407735 tests: Fix function mocking for clang
clang seems to like to do some aggressive optimizations that break our
approach of mocking functions for test by using objcopy to turn them
weak after the fact on individual compiled object files. For example, in
CB:56601 the function cbfs_get_boot_device() is mocked this way. When
compiling the cbfs_boot_lookup() function in src/lib/cbfs.c with clang,
it will generate a normal callq instruction to a relocation for
cbfs_boot_lookup(), which can then later be pointed to the mocked
version of that function. However, it will also somehow infer that the
version of cbfs_boot_lookup() in that file can only ever return a
pointer to the static local `ro` variable (because CONFIG_VBOOT is
disabled in the environment for that particular test), and instead
generate instructions that directly load the address of a relocation for
that variable into %rdi for the following call to cbfs_lookup(), rather
than using the real function return value. (Why it would do that is
anyone's guess because this seems unlikely to be faster than just moving
the function return value from %rax into %rdi like a normal compiler.)

Long story short, this optimization breaks our tests because
cbfs_lookup() will be called with the wrong pointer. clang doesn't
provide many options to disable individual optimizations, so the only
solution seems to be to make clang aware that the function is weak
during the compilation stage already, so it can be aware that it may get
replaced. This patch implements that by marking the mocked functions
weak via #pragma weak lines in the per-test autogenerated config header.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I1f9011f444248544de7a71bbefc54edc006ae0cd
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57009
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Jakub Czapiga <jacz@semihalf.com>
2021-08-25 20:54:16 +00:00

291 lines
10 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0-only
testsrc := $(top)/tests
# Place the build output in one of two places depending on COV, so that code
# built with code coverage never mixes with code built without code coverage.
ifeq ($(COV),1)
testobj := $(obj)/coverage
else
testobj := $(obj)/tests
endif
cmockasrc := 3rdparty/cmocka
cmockaobj := $(objutil)/cmocka
coverage_dir := coverage_reports
CMOCKA_LIB := $(cmockaobj)/src/libcmocka.so
CMAKE := cmake
OBJCOPY ?= objcopy
OBJDUMP ?= objdump
TEST_DEFAULT_CONFIG := $(top)/configs/config.emulation_qemu_x86_i440fx
TEST_DOTCONFIG := $(testobj)/.config
TEST_KCONFIG_AUTOHEADER := $(testobj)/config.src.h
TEST_KCONFIG_AUTOCONFIG := $(testobj)/auto.conf
TEST_KCONFIG_DEPENDENCIES := $(testobj)/auto.conf.cmd
TEST_KCONFIG_SPLITCONFIG := $(testobj)/config/
TEST_KCONFIG_TRISTATE := $(testobj)/tristate.conf
TEST_CFLAGS := -include $(src)/include/kconfig.h \
-include $(src)/commonlib/bsd/include/commonlib/bsd/compiler.h \
-include $(src)/include/rules.h
# Include generic test mock headers, before original ones
TEST_CFLAGS += -I$(testsrc)/include/mocks -I$(testsrc)/include
TEST_CFLAGS += -I$(src) -I$(src)/include -I$(src)/commonlib/include \
-I$(src)/commonlib/bsd/include -I$(src)/arch/x86/include \
-I$(top)/3rdparty/vboot/firmware/include
# Note: This is intentionally just a subset of the warnings in the toplevel
# Makefile.inc. We don't need to be as strict with test code, and things like
# -Wmissing-prototypes just make working with the test framework cumbersome.
# Only put conservative warnings here that really detect code that's obviously
# unintentional.
TEST_CFLAGS += -Wall -Werror -Wundef -Wstrict-prototypes -Wno-inline-asm
# Path for Kconfig autoheader
TEST_CFLAGS += -I$(dir $(TEST_KCONFIG_AUTOHEADER))
TEST_CFLAGS += -std=gnu11 -Os -ffunction-sections -fdata-sections -fno-builtin
TEST_CFLAGS += -D__TEST__
TEST_CFLAGS += -I$(cmockasrc)/include
# Link against Cmocka
TEST_LDFLAGS := -L$(cmockaobj)/src -lcmocka -Wl,-rpath=$(cmockaobj)/src
TEST_LDFLAGS += -Wl,--gc-sections
# Some memlayout symbols don't work with userspace relocation -- disable it.
TEST_CFLAGS += -fno-pie -fno-pic
TEST_LDFLAGS += -no-pie
# Enable code coverage if COV=1
ifeq ($(COV),1)
TEST_CFLAGS += --coverage
TEST_LDFLAGS += --coverage
endif
# Extra attributes for unit tests, declared per test
attributes := srcs cflags config mocks stage
stages := decompressor bootblock romstage smm verstage
stages += ramstage rmodule postcar libagesa
alltests :=
subdirs := tests/arch tests/acpi tests/commonlib tests/console tests/cpu
subdirs += tests/device tests/drivers tests/ec tests/lib tests/mainboard
subdirs += tests/northbridge tests/security tests/soc tests/southbridge
subdirs += tests/superio tests/vendorcode
define tests-handler
alltests += $(1)$(2)
$(foreach attribute,$(attributes),
$(eval $(1)$(2)-$(attribute) += $($(2)-$(attribute))))
$(foreach attribute,$(attributes),
$(eval $(2)-$(attribute) := ))
# Sanity check for stage attribute value
$(eval $(1)$(2)-stage := $(if $($(1)$(2)-stage),$($(1)$(2)-stage),ramstage))
$(if $(findstring $($(1)$(2)-stage), $(stages)),,
$(error Wrong $(1)$(2)-stage value $($(1)$(2)-stage). \
Check your $(dir $(1)$(2))Makefile.inc))
endef
# Copy attributes of one test to another.
# $1 - input test name
# $2 - output test name
copy-test = $(foreach attr,$(attributes), \
$(eval $(strip $(2))-$(attr) := $($(strip $(1))-$(attr))))
$(call add-special-class, tests)
$(call evaluate_subdirs)
# Create actual targets for unit test binaries
# $1 - test name
define TEST_CC_template
# Generate custom config.h redefining given config symbols, and declaring mocked
# functions weak. It is important that the compiler already sees that they are
# weak (and they aren't just turned weak at a later stage) to prevent certain
# optimizations that would break if the function gets replaced. (For clang this
# file needs to be marked `system_header` to prevent it from warning about
# #pragma weak entries without a matching function declaration, since there's no
# -Wno-xxx command line option for that.)
$(1)-config-file := $(testobj)/$(1)/config.h
$$($(1)-config-file): $(TEST_KCONFIG_AUTOHEADER)
mkdir -p $$(dir $$@)
printf '// File generated by tests/Makefile.inc\n// Do not change\n' > $$@
printf '#include <%s>\n\n' "$(notdir $(TEST_KCONFIG_AUTOHEADER))" >> $$@
for kv in $$($(1)-config); do \
key="`echo $$$$kv | cut -d '=' -f -1`"; \
value="`echo $$$$kv | cut -d '=' -f 2-`"; \
printf '#undef %s\n' "$$$$key" >> $$@; \
printf '#define %s %s\n\n' "$$$$key" "$$$$value" >> $$@; \
done
printf '#ifdef __clang__\n' >> $$@;
printf '#pragma clang system_header\n' >> $$@;
printf '#endif\n' >> $$@;
printf '#ifdef __TEST_SRCOBJ__\n' >> $$@;
for m in $$($(1)-mocks); do \
printf '#pragma weak %s\n' "$$$$m" >> $$@; \
done
printf '#endif\n' >> $$@;
$($(1)-objs): TEST_CFLAGS += -I$$(dir $$($(1)-config-file)) \
-D__$$(shell echo $$($(1)-stage) | tr '[:lower:]' '[:upper:]')__
# Give us a way to distinguish between coreboot source files and test files in code.
$($(1)-srcobjs): TEST_CFLAGS += -D__TEST_SRCOBJ__
# Compile sources and apply mocking/wrapping of selected symbols.
# For each listed mock add new symbol with prefix `__real_`,
# and pointing to the same section:address.
$($(1)-objs): $(testobj)/$(1)/%.o: $$$$*.c $$($(1)-config-file)
mkdir -p $$(dir $$@)
$(HOSTCC) $(HOSTCFLAGS) $$(TEST_CFLAGS) $($(1)-cflags) -MMD \
-MF $$(basename $$@).d -MT $$@ -c $$< -o $$@.orig
objcopy_wrap_flags=''; \
for sym in $$($(1)-mocks); do \
sym_line="$$$$($(OBJDUMP) -t $$@.orig | grep -E "[0-9a-fA-F]+\\s+w\\s+F\\s+.*\\s$$$$sym$$$$")"; \
if [ ! -z "$$$$sym_line" ] ; then \
addr="$$$$(echo \"$$$$sym_line\" | awk '{ print $$$$1 }')"; \
section="$$$$(echo \"$$$$sym_line\" | awk '{ print $$$$(NF - 2) }')"; \
objcopy_wrap_flags="$$$$objcopy_wrap_flags --add-symbol __real_$$$${sym}=$$$${section}:0x$$$${addr},function,global"; \
fi \
done ; \
$(OBJCOPY) $$@.orig $$$$objcopy_wrap_flags $$@
$($(1)-bin): $($(1)-objs) $(CMOCKA_LIB)
$(HOSTCC) $$^ $($(1)-cflags) $$(TEST_LDFLAGS) -o $$@
endef
$(foreach test, $(alltests), \
$(eval $(test)-srcobjs := $(addprefix $(testobj)/$(test)/, \
$(patsubst %.c,%.o,$(filter src/%,$($(test)-srcs))))) \
$(eval $(test)-objs := $(addprefix $(testobj)/$(test)/, \
$(patsubst %.c,%.o,$($(test)-srcs)))))
$(foreach test, $(alltests), \
$(eval $(test)-bin := $(testobj)/$(test)/run))
$(foreach test, $(alltests), \
$(eval $(call TEST_CC_template,$(test))))
$(foreach test, $(alltests), \
$(eval all-test-objs += $($(test)-objs)))
$(foreach test, $(alltests), \
$(eval test-bins += $($(test)-bin)))
DEPENDENCIES += $(addsuffix .d,$(basename $(all-test-objs)))
-include $(DEPENDENCIES)
# Build cmocka
$(CMOCKA_LIB):
echo "*** Building CMOCKA ***"
mkdir -p $(cmockaobj)
cd $(cmockaobj) && $(CMAKE) $(abspath $(cmockasrc))
$(MAKE) -C $(cmockaobj)
# Kconfig targets
$(TEST_DOTCONFIG):
mkdir -p $(dir $@)
cp $(TEST_DEFAULT_CONFIG) $(TEST_DOTCONFIG)
# Don't override default Kconfig variables, since this will affect all
# Kconfig targets. Change them only when calling sub-make instead.
$(TEST_KCONFIG_AUTOHEADER): TEST_KCONFIG_FLAGS := DOTCONFIG=$(TEST_DOTCONFIG) \
KCONFIG_AUTOHEADER=$(TEST_KCONFIG_AUTOHEADER) \
KCONFIG_AUTOCONFIG=$(TEST_KCONFIG_AUTOCONFIG) \
KCONFIG_DEPENDENCIES=$(TEST_KCONFIG_DEPENDENCIES) \
KCONFIG_SPLITCONFIG=$(TEST_KCONFIG_SPLITCONFIG) \
KCONFIG_TRISTATE=$(TEST_KCONFIG_TRISTATE) \
KBUILD_DEFCONFIG=$(TEST_DEFAULT_CONFIG)
$(TEST_KCONFIG_AUTOHEADER): $(TEST_DOTCONFIG) $(objutil)/kconfig/conf
mkdir -p $(dir $@)
$(MAKE) $(TEST_KCONFIG_FLAGS) olddefconfig
$(MAKE) $(TEST_KCONFIG_FLAGS) syncconfig
$(TEST_KCONFIG_AUTOCONFIG): $(TEST_KCONFIG_AUTOHEADER)
true
.PHONY: $(alltests) $(addprefix clean-,$(alltests))
.PHONY: unit-tests build-unit-tests run-unit-tests clean-unit-tests
ifeq ($(JUNIT_OUTPUT),y)
$(alltests): export CMOCKA_MESSAGE_OUTPUT=xml
$(alltests): export CMOCKA_XML_FILE=$(testobj)/junit-$(subst /,_,$^)-%g.xml
endif
$(alltests): $$($$(@)-bin)
rm -f $(testobj)/junit-$(subst /,_,$^).xml $(testobj)/$(subst /,_,$^).failed
-./$^ || echo failed > $(testobj)/$(subst /,_,$^).failed
# Build a code coverage report by collecting all the gcov files into a single
# report. If COV is not set, this might be a user error, and they're trying
# to generate a coverage report without first having built and run the code
# with code coverage. So instead of silently correcting it by adding COV=1,
# let's flag it to the user so they can be sure they're doing the thing they
# want to do.
.PHONY: coverage-report clean-coverage-report
ifeq ($(COV),1)
coverage-report:
lcov -o $(testobj)/tests.info -c -d $(testobj) --exclude '$(testsrc)/*'
genhtml -q -o $(testobj)/$(coverage_dir) -t "coreboot unit tests" \
-s $(testobj)/tests.info
clean-coverage-report:
rm -Rf $(testobj)/$(coverage_dir)
else
coverage-report:
COV=1 V=$(V) $(MAKE) coverage-report
clean-coverage-report:
COV=1 V=$(V) $(MAKE) clean-coverage-report
endif
unit-tests: build-unit-tests run-unit-tests
build-unit-tests: $(test-bins)
run-unit-tests: $(alltests)
if [ `find $(testobj) -name '*.failed' | wc -l` -gt 0 ]; then \
echo "**********************"; \
echo " TESTS FAILED"; \
echo "**********************"; \
exit 1; \
else \
echo "**********************"; \
echo " ALL TESTS PASSED"; \
echo "**********************"; \
exit 0; \
fi
$(addprefix clean-,$(alltests)): clean-%:
rm -rf $(testobj)/$*
clean-unit-tests:
rm -rf $(testobj)
list-unit-tests:
@echo "unit-tests:"
for t in $(sort $(alltests)); do \
echo " $$t"; \
done
help-unit-tests help::
@echo '*** coreboot unit-tests targets ***'
@echo ' Use "COV=1 make [target]" to enable code coverage for unit tests'
@echo ' unit-tests - Run all unit-tests from tests/'
@echo ' clean-unit-tests - Remove unit-tests build artifacts'
@echo ' list-unit-tests - List all unit-tests'
@echo ' <unit-test> - Build and run single unit-test'
@echo ' clean-<unit-test> - Remove single unit-test build artifacts'
@echo ' coverage-report - Generate a code coverage report'
@echo ' clean-coverage-report - Remove the code coverage report'
@echo