u-boot-brain/scripts/gen_ll_addressable_symbols.sh

#!/bin/bash
# SPDX-License-Identifier: GPL-2.0+
# Copyright (C) 2020 Marek Behún <marek.behun@nic.cz>

# Generate __ADDRESSABLE(symbol) for every linker list entry symbol, so that LTO
# does not optimize these symbols away

set -e

echo '#include <common.h>'
$NM "$@" 2>/dev/null | grep -oe '_u_boot_list_2_[a-zA-Z0-9_]*_2_[a-zA-Z0-9_]*' | \
	sort -u | sed -e 's/^\(.*\)/extern char \1[];\n__ADDRESSABLE(\1);/'
build: support building with Link Time Optimizations Add plumbing for building U-Boot with Link Time Optimizations. When building with LTO, $(PLATFORM_LIBS) has to be in --whole-archive / --no-whole-archive group, otherwise some functions declared in assembly may not be resolved and linking may fail. Note: clang may throw away linker list symbols it thinks are unused when compiling with LTO. To force these symbols to be included, we refer to them via the __ADDRESSABLE macro in a C file generated from compiled built-in.o files before linking. Signed-off-by: Marek Behún <marek.behun@nic.cz> Reviewed-by: Simon Glass <sjg@chromium.org> 2021-05-20 20:24:03 +09:00			`#!/bin/bash`
			`# SPDX-License-Identifier: GPL-2.0+`
			`# Copyright (C) 2020 Marek Behún <marek.behun@nic.cz>`

			`# Generate __ADDRESSABLE(symbol) for every linker list entry symbol, so that LTO`
			`# does not optimize these symbols away`

			`set -e`

			`echo '#include <common.h>'`
			`$NM "$@" 2>/dev/null \| grep -oe '_u_boot_list_2_[a-zA-Z0-9_]_2_[a-zA-Z0-9_]' \| \`
			`sort -u \| sed -e 's/^\(.*\)/extern char \1[];\n__ADDRESSABLE(\1);/'`