kernel_optimize_test/arch/i386/Makefile
Ingo Molnar 25165120f2 [PATCH] x86: add -freg-struct-return to CFLAGS
Jeremy Fitzhardinge suggested the use of -freg-struct-return, which does
structure-returns (such as when using pte_t) in registers instead of on
the stack.

that is indeed so, and this option reduced the kernel size a bit:

    text    data     bss     dec     hex filename
 4799506  543456 3760128 9103090  8ae6f2 vmlinux.before
 4798117  543456 3760128 9101701  8ae185 vmlinux.after

the resulting kernel booted fine on my testbox. Lets go for it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-26 12:53:30 -08:00

160 lines
5.1 KiB
Makefile

#
# i386/Makefile
#
# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies. Remember to do have actions
# for "archclean" cleaning up for this architecture.
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
# Copyright (C) 1994 by Linus Torvalds
#
# 19990713 Artur Skawina <skawina@geocities.com>
# Added '-march' and '-mpreferred-stack-boundary' support
#
# 20050320 Kianusch Sayah Karadji <kianusch@sk-tech.net>
# Added support for GEODE CPU
HAS_BIARCH := $(call cc-option-yn, -m32)
ifeq ($(HAS_BIARCH),y)
AS := $(AS) --32
LD := $(LD) -m elf_i386
CC := $(CC) -m32
endif
LDFLAGS := -m elf_i386
OBJCOPYFLAGS := -O binary -R .note -R .comment -S
ifdef CONFIG_RELOCATABLE
LDFLAGS_vmlinux := --emit-relocs
endif
CHECKFLAGS += -D__i386__
CFLAGS += -pipe -msoft-float -mregparm=3 -freg-struct-return
# prevent gcc from keeping the stack 16 byte aligned
CFLAGS += $(call cc-option,-mpreferred-stack-boundary=2)
# CPU-specific tuning. Anything which can be shared with UML should go here.
include $(srctree)/arch/i386/Makefile.cpu
# temporary until string.h is fixed
cflags-y += -ffreestanding
# this works around some issues with generating unwind tables in older gccs
# newer gccs do it by default
cflags-y += -maccumulate-outgoing-args
# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
# a lot more stack due to the lack of sharing of stacklots:
CFLAGS += $(shell if [ $(call cc-version) -lt 0400 ] ; then echo $(call cc-option,-fno-unit-at-a-time); fi ;)
# do binutils support CFI?
cflags-y += $(call as-instr,.cfi_startproc\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
# is .cfi_signal_frame supported too?
cflags-y += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
CFLAGS += $(cflags-y)
# Default subarch .c files
mcore-y := mach-default
# Voyager subarch support
mflags-$(CONFIG_X86_VOYAGER) := -Iinclude/asm-i386/mach-voyager
mcore-$(CONFIG_X86_VOYAGER) := mach-voyager
# VISWS subarch support
mflags-$(CONFIG_X86_VISWS) := -Iinclude/asm-i386/mach-visws
mcore-$(CONFIG_X86_VISWS) := mach-visws
# NUMAQ subarch support
mflags-$(CONFIG_X86_NUMAQ) := -Iinclude/asm-i386/mach-numaq
mcore-$(CONFIG_X86_NUMAQ) := mach-default
# BIGSMP subarch support
mflags-$(CONFIG_X86_BIGSMP) := -Iinclude/asm-i386/mach-bigsmp
mcore-$(CONFIG_X86_BIGSMP) := mach-default
#Summit subarch support
mflags-$(CONFIG_X86_SUMMIT) := -Iinclude/asm-i386/mach-summit
mcore-$(CONFIG_X86_SUMMIT) := mach-default
# generic subarchitecture
mflags-$(CONFIG_X86_GENERICARCH) := -Iinclude/asm-i386/mach-generic
mcore-$(CONFIG_X86_GENERICARCH) := mach-default
core-$(CONFIG_X86_GENERICARCH) += arch/i386/mach-generic/
# ES7000 subarch support
mflags-$(CONFIG_X86_ES7000) := -Iinclude/asm-i386/mach-es7000
mcore-$(CONFIG_X86_ES7000) := mach-default
core-$(CONFIG_X86_ES7000) := arch/i386/mach-es7000/
# default subarch .h files
mflags-y += -Iinclude/asm-i386/mach-default
head-y := arch/i386/kernel/head.o arch/i386/kernel/init_task.o
libs-y += arch/i386/lib/
core-y += arch/i386/kernel/ \
arch/i386/mm/ \
arch/i386/$(mcore-y)/ \
arch/i386/crypto/
drivers-$(CONFIG_MATH_EMULATION) += arch/i386/math-emu/
drivers-$(CONFIG_PCI) += arch/i386/pci/
# must be linked after kernel/
drivers-$(CONFIG_OPROFILE) += arch/i386/oprofile/
drivers-$(CONFIG_PM) += arch/i386/power/
CFLAGS += $(mflags-y)
AFLAGS += $(mflags-y)
boot := arch/i386/boot
PHONY += zImage bzImage compressed zlilo bzlilo \
zdisk bzdisk fdimage fdimage144 fdimage288 isoimage install
all: bzImage
# KBUILD_IMAGE specify target image being built
KBUILD_IMAGE := $(boot)/bzImage
zImage zlilo zdisk: KBUILD_IMAGE := arch/i386/boot/zImage
zImage bzImage: vmlinux
$(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
compressed: zImage
zlilo bzlilo: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(KBUILD_IMAGE) zlilo
zdisk bzdisk: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(KBUILD_IMAGE) zdisk
fdimage fdimage144 fdimage288 isoimage: vmlinux
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(KBUILD_IMAGE) $@
install:
$(Q)$(MAKE) $(build)=$(boot) BOOTIMAGE=$(KBUILD_IMAGE) install
archclean:
$(Q)$(MAKE) $(clean)=arch/i386/boot
define archhelp
echo '* bzImage - Compressed kernel image (arch/$(ARCH)/boot/bzImage)'
echo ' install - Install kernel using'
echo ' (your) ~/bin/installkernel or'
echo ' (distribution) /sbin/installkernel or'
echo ' install to $$(INSTALL_PATH) and run lilo'
echo ' bzdisk - Create a boot floppy in /dev/fd0'
echo ' fdimage - Create a boot floppy image'
echo ' isoimage - Create a boot CD-ROM image'
endef
CLEAN_FILES += arch/$(ARCH)/boot/fdimage \
arch/$(ARCH)/boot/image.iso \
arch/$(ARCH)/boot/mtools.conf