From e04733ee53069a993a841bc0747c5c7290791230 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 1 Sep 2014 16:41:28 +0000 Subject: [PATCH] Support slim LTO bootstrap Change the bootstrap-lto config file to use slim (non fat) LTO.. Speeds up the LTO bootstrap by ~18% on a 4 core system. This requires using gcc-ar/ranlib in post stage 1 builds, so these are passed to all sub builds. config/: 2014-09-01 Andi Kleen * bootstrap-lto.mk: Implement slim bootstrap. /: 2014-09-01 Andi Kleen * Makefile.tpl (POSTSTAGE1_HOST_EXPORTS): Add LTO_EXPORTS. POSTSTAGE1_FLAGS_TO_PASS): Add LTO_FLAGS_TO_PASS. * Makefile.in: Regenerate. From-SVN: r214801 --- ChangeLog | 6 ++++++ Makefile.in | 2 ++ Makefile.tpl | 2 ++ config/ChangeLog | 4 ++++ config/bootstrap-lto.mk | 16 +++++++++++----- 5 files changed, 25 insertions(+), 5 deletions(-) diff --git a/ChangeLog b/ChangeLog index 35c9dc6c443..a0f8c221a51 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2014-09-01 Andi Kleen + + * Makefile.tpl (POSTSTAGE1_HOST_EXPORTS): Add LTO_EXPORTS. + POSTSTAGE1_FLAGS_TO_PASS): Add LTO_FLAGS_TO_PASS. + * Makefile.in: Regenerate. + 2014-08-28 David Malcolm * rtx-classes-status.txt: Delete diff --git a/Makefile.in b/Makefile.in index add8cf6b379..d6105b34924 100644 --- a/Makefile.in +++ b/Makefile.in @@ -257,6 +257,7 @@ POSTSTAGE1_HOST_EXPORTS = \ $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CC; \ CC_FOR_BUILD="$$CC"; export CC_FOR_BUILD; \ $(POSTSTAGE1_CXX_EXPORT) \ + $(LTO_EXPORTS) \ GNATBIND="$$r/$(HOST_SUBDIR)/prev-gcc/gnatbind"; export GNATBIND; \ LDFLAGS="$(POSTSTAGE1_LDFLAGS) $(BOOT_LDFLAGS)"; export LDFLAGS; \ HOST_LIBS="$(POSTSTAGE1_LIBS)"; export HOST_LIBS; @@ -828,6 +829,7 @@ POSTSTAGE1_FLAGS_TO_PASS = \ GNATBIND="$${GNATBIND}" \ LDFLAGS="$${LDFLAGS}" \ HOST_LIBS="$${HOST_LIBS}" \ + $(LTO_FLAGS_TO_PASS) \ "`echo 'ADAFLAGS=$(BOOT_ADAFLAGS)' | sed -e s'/[^=][^=]*=$$/XFOO=/'`" # Flags to pass down to makes which are built with the target environment. diff --git a/Makefile.tpl b/Makefile.tpl index 00dba363a9d..f7c7e38cdde 100644 --- a/Makefile.tpl +++ b/Makefile.tpl @@ -260,6 +260,7 @@ POSTSTAGE1_HOST_EXPORTS = \ $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CC; \ CC_FOR_BUILD="$$CC"; export CC_FOR_BUILD; \ $(POSTSTAGE1_CXX_EXPORT) \ + $(LTO_EXPORTS) \ GNATBIND="$$r/$(HOST_SUBDIR)/prev-gcc/gnatbind"; export GNATBIND; \ LDFLAGS="$(POSTSTAGE1_LDFLAGS) $(BOOT_LDFLAGS)"; export LDFLAGS; \ HOST_LIBS="$(POSTSTAGE1_LIBS)"; export HOST_LIBS; @@ -633,6 +634,7 @@ POSTSTAGE1_FLAGS_TO_PASS = \ GNATBIND="$${GNATBIND}" \ LDFLAGS="$${LDFLAGS}" \ HOST_LIBS="$${HOST_LIBS}" \ + $(LTO_FLAGS_TO_PASS) \ "`echo 'ADAFLAGS=$(BOOT_ADAFLAGS)' | sed -e s'/[^=][^=]*=$$/XFOO=/'`" # Flags to pass down to makes which are built with the target environment. diff --git a/config/ChangeLog b/config/ChangeLog index 82c73bd5cde..a1653c6328a 100644 --- a/config/ChangeLog +++ b/config/ChangeLog @@ -1,3 +1,7 @@ +2014-09-01 Andi Kleen + + * bootstrap-lto.mk: Implement slim bootstrap. + 2014-08-21 Bin Cheng * isl.m4 (ISL_CHECK_VERSION): Check link of isl library diff --git a/config/bootstrap-lto.mk b/config/bootstrap-lto.mk index 27bad1529be..9e065e1d85a 100644 --- a/config/bootstrap-lto.mk +++ b/config/bootstrap-lto.mk @@ -1,7 +1,13 @@ -# This option enables LTO for stage2 and stage3. -# FIXME: Our build system is not yet able to use gcc-ar wrapper, so we need -# to go with -ffat-lto-objects. +# This option enables LTO for stage2 and stage3 in slim mode -STAGE2_CFLAGS += -flto=jobserver -frandom-seed=1 -ffat-lto-objects -STAGE3_CFLAGS += -flto=jobserver -frandom-seed=1 -ffat-lto-objects +STAGE2_CFLAGS += -flto=jobserver -frandom-seed=1 +STAGE3_CFLAGS += -flto=jobserver -frandom-seed=1 STAGEprofile_CFLAGS += -fno-lto + +# assumes the host supports the linker plugin +LTO_AR = $$r/$(HOST_SUBDIR)/prev-gcc/gcc-ar$(exeext) -B$$r/$(HOST_SUBDIR)/prev-gcc/ +LTO_RANLIB = $$r/$(HOST_SUBDIR)/prev-gcc/gcc-ranlib$(exeext) -B$$r/$(HOST_SUBDIR)/prev-gcc/ + +LTO_EXPORTS = AR="$(LTO_AR)"; export AR; \ + RANLIB="$(LTO_RANLIB)"; export RANLIB; +LTO_FLAGS_TO_PASS = AR="$(LTO_AR)" RANLIB="$(LTO_RANLIB)" -- 2.30.2