AS = $(CROSS_COMPILE)as
+LD = $(CROSS_COMPILE)ld
ifeq ($(clang),y)
-LD = $(CROSS_COMPILE)gold
CC = $(CROSS_COMPILE)clang
+LD_LTO = $(CROSS_COMPILE)llvm-ld
else
-LD = $(CROSS_COMPILE)ld
CC = $(CROSS_COMPILE)gcc
+LD_LTO = $(CROSS_COMPILE)ld
endif
CPP = $(CC) -E
AR = $(CROSS_COMPILE)ar
CFLAGS += -fno-optimize-sibling-calls
endif
endif
+
+ifeq ($(lto),y)
+CFLAGS += -flto
+ifeq ($(clang),y)
+LDFLAGS += -plugin LLVMgold.so
+endif
+endif
$(MAKE) -f $(BASEDIR)/Rules.mk -C $(*D) $(@F)
%/: FORCE
- $(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in.o
+ $(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in.o built_in_bin.o
lock_profile ?= n
crash_debug ?= n
frame_pointer ?= n
+clang ?= n
+lto ?= n
XEN_ROOT=$(BASEDIR)/..
include $(XEN_ROOT)/Config.mk
# Most CFLAGS are safe for assembly files:
# -std=gnu{89,99} gets confused by #-prefixed end-of-line comments
-AFLAGS += $(AFLAGS-y) $(filter-out -std=gnu%,$(CFLAGS))
+# -flto makes no sense and annoys clang
+AFLAGS += $(AFLAGS-y) $(filter-out -std=gnu%,$(filter-out -flto,$(CFLAGS)))
# LDFLAGS are only passed directly to $(LD)
LDFLAGS += $(LDFLAGS_DIRECT)
subdir-n := $(patsubst %,%/,$(patsubst %/,%,$(subdir-n) $(subdir-)))
subdir-y := $(patsubst %,%/,$(patsubst %/,%,$(subdir-y)))
-# Add explicitly declared subdirectories to the object list.
+# Add explicitly declared subdirectories to the object lists.
obj-y += $(patsubst %/,%/built_in.o,$(subdir-y))
-# Add implicitly declared subdirectories (in the object list) to the
+# Add implicitly declared subdirectories (in the object lists) to the
# subdirectory list, and rewrite the object-list entry.
subdir-y += $(filter %/,$(obj-y))
obj-y := $(patsubst %/,%/built-in.o,$(obj-y))
subdir-all := $(subdir-y) $(subdir-n)
+ifeq ($(lto),y)
+# Would like to handle all object files as bitcode, but objects made from
+# pure asm are in a different format and have to be collected separately.
+# Mirror the directory tree, collecting them as built_in_bin.o.
+# If there are no binary objects in a given directory, make a dummy .o
+obj-bin-y += $(patsubst %/built_in.o,%/built_in_bin.o,$(filter %/built_in.o,$(obj-y)))
+else
+# For a non-LTO build, bundle obj-bin targets in with the normal objs.
+obj-y += $(obj-bin-y)
+obj-bin-y :=
+endif
+
built_in.o: $(obj-y)
+ifeq ($(obj-y),)
+ $(CC) $(CFLAGS) -c -x c /dev/null -o $@
+else
+ifeq ($(lto),y)
+ $(LD_LTO) -r -o $@ $^
+else
+ $(LD) $(LDFLAGS) -r -o $@ $^
+endif
+endif
+
+built_in_bin.o: $(obj-bin-y)
+ifeq ($(obj-bin-y),)
+ $(CC) $(AFLAGS) -c -x assembler /dev/null -o $@
+else
$(LD) $(LDFLAGS) -r -o $@ $^
+endif
# Force execution of pattern rules (for which PHONY cannot be directly used).
.PHONY: FORCE
%/built_in.o: FORCE
$(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in.o
+%/built_in_bin.o: FORCE
+ $(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in_bin.o
+
.PHONY: clean
clean:: $(addprefix _clean_, $(subdir-all))
rm -f *.o *~ core $(DEPS)
obj-y += apic.o
obj-y += bitops.o
-obj-y += clear_page.o
-obj-y += copy_page.o
+obj-bin-y += clear_page.o
+obj-bin-y += copy_page.o
obj-y += compat.o
obj-y += debug.o
obj-y += delay.o
./boot/mkelf32 $(TARGET)-syms $(TARGET) 0x100000 \
`$(NM) -nr $(TARGET)-syms | head -n 1 | sed -e 's/^\([^ ]*\).*/0x\1/'`
+
ALL_OBJS := $(BASEDIR)/arch/x86/boot/built_in.o $(ALL_OBJS)
-$(TARGET)-syms: $(ALL_OBJS) xen.lds
+ifeq ($(lto),y)
+# Gather all LTO objects together
+prelink_lto.o: $(ALL_OBJS)
+ $(LD_LTO) -r -o $@ $^
+
+# Link it with all the binary objects
+prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o
+ $(LD) $(LDFLAGS) -r -o $@ $^
+else
+prelink.o: $(ALL_OBJS)
+ $(LD) $(LDFLAGS) -r -o $@ $^
+endif
+
+$(TARGET)-syms: prelink.o xen.lds
$(MAKE) -f $(BASEDIR)/Rules.mk $(BASEDIR)/common/symbols-dummy.o
- $(LD) $(LDFLAGS) -T xen.lds -N $(ALL_OBJS) \
+ $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \
$(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0
$(NM) -n $(@D)/.$(@F).0 | $(BASEDIR)/tools/symbols >$(@D)/.$(@F).0.S
$(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o
- $(LD) $(LDFLAGS) -T xen.lds -N $(ALL_OBJS) \
+ $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \
$(@D)/.$(@F).0.o -o $(@D)/.$(@F).1
$(NM) -n $(@D)/.$(@F).1 | $(BASEDIR)/tools/symbols >$(@D)/.$(@F).1.S
$(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o
- $(LD) $(LDFLAGS) -T xen.lds -N $(ALL_OBJS) \
+ $(LD) $(LDFLAGS) -T xen.lds -N prelink.o \
$(@D)/.$(@F).1.o -o $@
rm -f $(@D)/.$(@F).[0-9]*
asm-offsets.s: $(TARGET_SUBARCH)/asm-offsets.c
- $(CC) $(CFLAGS) -S -o $@ $<
+ $(CC) $(filter-out -flto,$(CFLAGS)) -S -o $@ $<
xen.lds: xen.lds.S
$(CC) -P -E -Ui386 $(AFLAGS) -o $@ $<
subdir-y += cpufreq
-obj-y += boot.o
-obj-y += power.o suspend.o wakeup_prot.o cpu_idle.o cpuidle_menu.o
+obj-y += boot.o power.o suspend.o cpu_idle.o cpuidle_menu.o
+obj-bin-y += wakeup_prot.o
-obj-y += head.o
+obj-bin-y += head.o
head.o: reloc.S
$(call cc-options-add,CFLAGS,CC,$(EMBEDDED_EXTRA_CFLAGS))
CFLAGS += -Werror -fno-builtin -msoft-float
+CFLAGS := $(filter-out -flto,$(CFLAGS))
# NB. awk invocation is a portable alternative to 'head -n -1'
%.S: %.bin
obj-y += asid.o
obj-y += emulate.o
-obj-y += entry.o
+obj-bin-y += entry.o
obj-y += intr.o
obj-y += svm.o
obj-y += vmcb.o
-obj-y += entry.o
+obj-bin-y += entry.o
obj-y += intr.o
obj-y += realmode.o
obj-y += vmcs.o
obj-y += domain_page.o
-obj-y += entry.o
-obj-y += gpr_switch.o
+obj-bin-y += entry.o
+obj-bin-y += gpr_switch.o
obj-y += mm.o
obj-y += seg_fixup.o
obj-y += traps.o
obj-$(crash_debug) += gdbstub.o
-obj-$(supervisor_mode_kernel) += supervisor_mode_kernel.o
+obj-bin-$(supervisor_mode_kernel) += supervisor_mode_kernel.o
subdir-y += compat
-obj-y += entry.o
-obj-y += gpr_switch.o
+obj-bin-y += entry.o
+obj-bin-y += gpr_switch.o
obj-y += mm.o
obj-y += traps.o
obj-y += machine_kexec.o
obj-y += mmconfig_64.o
obj-y += mmconfig-shared.o
obj-y += compat.o
-obj-y += compat_kexec.o
+obj-bin-y += compat_kexec.o
obj-y += domain.o
obj-y += physdev.o
obj-y += platform_hypercall.o
-obj-y += entry.o
+obj-bin-y += entry.o
-obj-y := libelf.o
+obj-bin-y := libelf.o
SECTIONS := text data rodata $(foreach n,1 2 4 8,rodata.str1.$(n)) $(foreach r,rel rel.ro,data.$(r) data.$(r).local)
projects / people / tklengyel / xen.git / commitdiff