Makefile keep track of variables (#79)

Signed-off-by: Thing-han, Lim <[email protected]>

.gitignore

@@ -5,3 +5,4 @@
 .vscode
 .idea
 test/bin/
+test/obj/

Makefile

@@ -1,32 +1,14 @@
 # SPDX-License-Identifier: Apache-2.0
 
-Q ?= @
-QEMU = qemu-aarch64
-CROSS_PREFIX ?=
-CC := $(CROSS_PREFIX)gcc
 
-INCLUDE_FIPS202 = -I fips202
-INCLUDE_MLKEM = -I mlkem
-INCLUDE_RANDOM = -I randombytes
-INCLUDE_NISTRANDOM = -I test/nistrng
-CFLAGS += -Wall -Wextra -Wpedantic -Werror -Wmissing-prototypes -Wredundant-decls \
-  -Wshadow -Wpointer-arith -Wno-unknown-pragmas -O3 -fomit-frame-pointer -pedantic \
-   ${INCLUDE_MLKEM} ${INCLUDE_FIPS202} $(ARCH_FLAGS)
-
-HOST_PLATFORM := $(shell uname -s)-$(shell uname -m)
-ifeq ($(HOST_PLATFORM),Linux-x86_64)
-	CFLAGS += -static
-endif
+.PHONY: all mlkem kat nistkat clean
 
-CYCLES ?= NO
+all: mlkem bench kat nistkat
 
-ifeq ($(CYCLES),PMU)
-	CFLAGS += -DPMU_CYCLES
-endif
+include mk/config.mk
 
-ifeq ($(CYCLES),PERF)
-	CFLAGS += -DPERF_CYCLES
-endif
+INCLUDE_RANDOM = -I randombytes
+INCLUDE_NISTRANDOM = -I test/nistrng
 
 CFLAGS_RANDOMBYTES = ${CFLAGS} ${INCLUDE_RANDOM}
 CFLAGS_NISTRANDOMBYTES = ${CFLAGS} ${INCLUDE_NISTRANDOM}
@@ -45,11 +27,6 @@ HEADERSKECCAKRANDOM = $(HEADERSKECCAK) randombytes/randombytes.h
 HEADERNISTKATS = $(HEADERSKECCAK) test/nistrng/aes.h test/nistrng/randombytes.h
 HEADERSBENCH = $(HEADERSKECCAKRANDOM) test/hal.h
 
-
-.PHONY: all mlkem kat nistkat clean
-
-all: mlkem bench kat nistkat
-
 mlkem: \
   test/bin/test_kyber512 \
   test/bin/test_kyber768 \
@@ -70,62 +47,62 @@ kat: \
   test/bin/gen_KAT768 \
   test/bin/gen_KAT1024
 
-test/bin/test_kyber512: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/test_kyber512: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=2 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/test_kyber768: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/test_kyber768: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=3 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/test_kyber1024: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/test_kyber1024: test/test_kyber.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=4 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/bench_kyber512: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH)
+test/bin/bench_kyber512: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=2 $(SOURCESBENCH) $< -o $@
 
-test/bin/bench_kyber768: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH)
+test/bin/bench_kyber768: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=3 $(SOURCESBENCH) $< -o $@
 
-test/bin/bench_kyber1024: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH)
+test/bin/bench_kyber1024: test/bench_kyber.c $(SOURCESBENCH) $(HEADERSBENCH) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=4 $(SOURCESBENCH) $< -o $@
 
-test/bin/gen_KAT512: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/gen_KAT512: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=2 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/gen_KAT768: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/gen_KAT768: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=3 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/gen_KAT1024: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM)
+test/bin/gen_KAT1024: test/gen_KAT.c $(SOURCESKECCAKRANDOM) $(HEADERSKECCAKRANDOM) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_RANDOMBYTES) -DKYBER_K=4 $(SOURCESKECCAKRANDOM) $< -o $@
 
-test/bin/gen_NISTKAT512: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS)
+test/bin/gen_NISTKAT512: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_NISTRANDOMBYTES) -DKYBER_K=2 $(SOURCESNISTKATS) $< -o $@
 
-test/bin/gen_NISTKAT768: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS)
+test/bin/gen_NISTKAT768: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_NISTRANDOMBYTES) -DKYBER_K=3 $(SOURCESNISTKATS) $< -o $@
 
-test/bin/gen_NISTKAT1024: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS)
+test/bin/gen_NISTKAT1024: test/gen_NISTKAT.c $(SOURCESNISTKATS) $(HEADERNISTKATS) $(CONFIG)
 	$(Q)echo "  CC      $@"
 	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
 	$(CC) $(CFLAGS_NISTRANDOMBYTES) -DKYBER_K=4 $(SOURCESNISTKATS) $< -o $@
@@ -138,3 +115,4 @@ emulate:
 clean:
 	-$(RM) -rf *.gcno *.gcda *.lcov *.o *.so
 	-$(RM) -rf test/bin
+	-$(RM) -rf test/obj

mk/config.mk

@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: Apache-2.0
+ifndef _CONFIG
+_CONFIG :=
+
+SRCDIR := $(CURDIR)
+
+##############
+# GCC config #
+##############
+CROSS_PREFIX ?= 
+CC := $(CROSS_PREFIX)gcc
+CPP := $(CROSS_PREFIX)cpp
+AR := $(CROSS_PREFIX)ar
+LD := $(CC)
+OBJCOPY := $(CROSS_PREFIX)objcopy
+SIZE := $(CROSS_PREFIX)size
+
+#################
+# Common config #
+#################
+CFLAGS += \
+	$(ARCH_FLAGS) \
+	-Wall \
+	-Wextra \
+	-Wpedantic \
+	-Werror \
+	-Wmissing-prototypes \
+	-Wredundant-decls \
+	-Wshadow \
+	-Wpointer-arith \
+	-Wno-unknown-pragmas \
+	-O3 \
+	-fomit-frame-pointer \
+	-pedantic \
+	-I mlkem \
+	-I fips202 \
+	$(CPPFLAGS)
+
+##################
+# Some Variables #
+##################
+Q ?= @
+QEMU = qemu-aarch64
+
+HOST_PLATFORM := $(shell uname -s)-$(shell uname -m)
+ifeq ($(HOST_PLATFORM),Linux-x86_64)
+	CFLAGS += -static
+endif
+
+CYCLES ?= NO
+
+ifeq ($(CYCLES),PMU)
+	CFLAGS += -DPMU_CYCLES
+endif
+
+ifeq ($(CYCLES),PERF)
+	CFLAGS += -DPERF_CYCLES
+endif
+
+##############################
+# Include retained variables #
+##############################
+
+RETAINED_VARS :=
+
+CONFIG := test/obj/.config.mk
+
+-include $(CONFIG)
+
+$(CONFIG):
+	@echo "  GEN     $@"
+	$(Q)[ -d $(@D) ] || mkdir -p $(@D)
+	@echo "# These variables are retained and can't be changed without a clean" > $@
+	@$(foreach var,$(RETAINED_VARS),echo "$(var) := $($(var))" >> $@; echo "LAST_$(var) := $($(var))" >> $@;)
+
+RETAINED_VARS += CYCLES
+
+define VAR_CHECK
+ifneq ($$(origin LAST_$(1)),undefined)
+ifneq "$$($(1))" "$$(LAST_$(1))"
+$$(info Variable $(1) changed, forcing rebuild!)
+.PHONY: $(CONFIG)
+endif
+endif
+endef
+
+$(foreach VAR,$(RETAINED_VARS),$(eval $(call VAR_CHECK,$(VAR))))
+endif