Apply memoization to cc-option macro by caching the results of the gcc calls. This macro is called very often so using cached results leads to faster compilation times.
Signed-off-by: Daniel Schwierzeck daniel.schwierzeck@googlemail.com --- Changes for v2: - move cache file to $(obj)/include/generated - reworked completely - cache also non-working gcc options - remove CACHE_CC_OPTIONS config switch and enable this optimization by default
config.mk | 23 +++++++++++++++++++++-- 1 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/config.mk b/config.mk index 918cffe..0da961a 100644 --- a/config.mk +++ b/config.mk @@ -107,8 +107,27 @@ HOSTCFLAGS += -pedantic # Option checker (courtesy linux kernel) to ensure # only supported compiler options are used # -cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \ - > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;) +CC_OPTIONS_CACHE_FILE := $(OBJTREE)/include/generated/cc_options.mk + +$(if $(wildcard $(CC_OPTIONS_CACHE_FILE)),,\ + $(shell mkdir -p $(dir $(CC_OPTIONS_CACHE_FILE)))) + +sinclude $(CC_OPTIONS_CACHE_FILE) + +_ccopt_sys = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \ + > /dev/null 2>&1; then \ + echo 'CC_OPTIONS += $(strip $1)' >> $(CC_OPTIONS_CACHE_FILE); \ + echo "$(1)"; else \ + [ "x$(strip $2)" != "x" ] && \ + echo 'CC_OPTIONS_NOP += $(strip $2)' >> $(CC_OPTIONS_CACHE_FILE); \ + echo "$(2)"; fi) + +_ccopt_cached = $(if $(filter $1,$(CC_OPTIONS)),$1,) +_ccopt_nop_cached = $(if $(filter $1,$(CC_OPTIONS_NOP)),$1,) + +cc-option = $(if $(call _ccopt_cached,$1),$1,\ + $(if $(call _ccopt_nop_cached,$2),$2,\ + $(call _ccopt_sys,$1,$2)))
# # Include the make variables (CC, etc...)