From 396979a67e538da087136ce01dbc4c7a670bf60e Mon Sep 17 00:00:00 2001 From: Jeff Epler Date: Sun, 11 Oct 2020 21:01:12 -0500 Subject: atmel-samd: parallelize lto linking This decreases the link time, especially on desktop machines with many CPU cores. However, it does come at a slight cost in binary size, making the flash section about 200 bytes bigger for circuitplayground_express. Before, linking build-circuitplayground_express/firmware.elf takes 8.8s elapsed time, leaving 3128 bytes free in flash. After, linking build-circuitplayground_express/firmware.elf takes 2.8s elapsed time, leaving 2924 bytes free in flash. (-6 seconds, -204 bytes free) If necessary, we can make this per-board or even per-translation to squeeze full builds. --- ports/atmel-samd/Makefile | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/ports/atmel-samd/Makefile b/ports/atmel-samd/Makefile index 1ee21679d..2593377eb 100644 --- a/ports/atmel-samd/Makefile +++ b/ports/atmel-samd/Makefile @@ -121,7 +121,7 @@ $(echo PERIPHERALS_CHIP_FAMILY=$(PERIPHERALS_CHIP_FAMILY)) ifeq ($(DEBUG), 1) CFLAGS += -ggdb3 -Og # You may want to disable -flto if it interferes with debugging. - CFLAGS += -flto -flto-partition=none + CFLAGS += -flto # You may want to enable these flags to make setting breakpoints easier. # CFLAGS += -fno-inline -fno-ipa-sra ifeq ($(CHIP_FAMILY), samd21) @@ -144,7 +144,7 @@ else CFLAGS += -finline-limit=$(CFLAGS_INLINE_LIMIT) endif - CFLAGS += -flto -flto-partition=none + CFLAGS += -flto ifeq ($(CIRCUITPY_FULL_BUILD),0) CFLAGS += --param inline-unit-growth=15 --param max-inline-insns-auto=20 @@ -197,6 +197,7 @@ endif LDFLAGS = $(CFLAGS) -nostartfiles -Wl,-nostdlib -Wl,-T,$(GENERATED_LD_FILE) -Wl,-Map=$@.map -Wl,-cref -Wl,-gc-sections -specs=nano.specs +LDFLAGS += -flto=$(shell nproc) LIBS := -lgcc -lc # Use toolchain libm if we're not using our own. -- cgit v1.2.3