| Message ID | 20190207220155.81351-4-ndesaulniers@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [1/4] init/Kconfig: add config support for detecting linker | expand |
On Thu, Feb 07, 2019 at 02:01:52PM -0800, ndesaulniers@google.com wrote: > -O2 enables tail merging of string table strings. > > For arm64: > 0.34% size improvement with lld -O2 over lld for vmlinux. > 3.30% size improvement with lld -O2 over lld for Image.lz4-dtb. > > Link: https://github.com/ClangBuiltLinux/linux/issues/343 > Suggested-by: Rui Ueyama <ruiu@google.com> > Suggested-by: Nathan Chancellor <natechancellor@gmail.com> > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com> > --- > Makefile | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Makefile b/Makefile > index 6307c17259ea..c07208ec49d4 100644 > --- a/Makefile > +++ b/Makefile > @@ -718,6 +718,10 @@ else > KBUILD_CFLAGS += -Wno-unused-but-set-variable > endif > > +ifdef CONFIG_LD_IS_LLD > +KBUILD_LDFLAGS += -O2 > +endif > + > KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) > ifdef CONFIG_FRAME_POINTER > KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls > -- > 2.20.1.791.gb4d0f1c61a-goog >
diff --git a/Makefile b/Makefile index 6307c17259ea..c07208ec49d4 100644 --- a/Makefile +++ b/Makefile @@ -718,6 +718,10 @@ else KBUILD_CFLAGS += -Wno-unused-but-set-variable endif +ifdef CONFIG_LD_IS_LLD +KBUILD_LDFLAGS += -O2 +endif + KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
-O2 enables tail merging of string table strings. For arm64: 0.34% size improvement with lld -O2 over lld for vmlinux. 3.30% size improvement with lld -O2 over lld for Image.lz4-dtb. Link: https://github.com/ClangBuiltLinux/linux/issues/343 Suggested-by: Rui Ueyama <ruiu@google.com> Suggested-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) -- 2.20.1.791.gb4d0f1c61a-goog