openwrt/target/linux/generic/patches-2.6.39/012-extra_optimization.patch
Felix Fietkau 127e4ebd32 generic: Add support for 2.6.39
Add support for 2.6.39 based on rc3. Runtime tested on bcm63xx.

SVN-Revision: 26615
2011-04-12 19:39:20 +00:00

25 lines
675 B
Diff

--- a/Makefile
+++ b/Makefile
@@ -543,9 +543,9 @@ endif # $(dot-config)
all: vmlinux
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
-KBUILD_CFLAGS += -Os
+KBUILD_CFLAGS += -Os -fno-caller-saves
else
-KBUILD_CFLAGS += -O2
+KBUILD_CFLAGS += -O2 -fno-reorder-blocks -fno-tree-ch -fno-caller-saves
endif
include $(srctree)/arch/$(SRCARCH)/Makefile
@@ -600,6 +600,9 @@ endif
NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
CHECKFLAGS += $(NOSTDINC_FLAGS)
+# improve gcc optimization
+CFLAGS += $(call cc-option,-funit-at-a-time,)
+
# warn about C99 declaration after statement
KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)