linux-sg2042/arch/x86/tools/calc_run_size.sh

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#!/bin/sh
#
# Calculate the amount of space needed to run the kernel, including room for
# the .bss and .brk sections.
#
# Usage:
# objdump -h a.out | sh calc_run_size.sh
NUM='\([0-9a-fA-F]*[ \t]*\)'
OUT=$(sed -n 's/^[ \t0-9]*.b[sr][sk][ \t]*'"$NUM$NUM$NUM$NUM"'.*/\1\4/p')
if [ -z "$OUT" ] ; then
echo "Never found .bss or .brk file offset" >&2
exit 1
fi
OUT=$(echo ${OUT# })
sizeA=$(printf "%d" 0x${OUT%% *})
OUT=${OUT#* }
offsetA=$(printf "%d" 0x${OUT%% *})
OUT=${OUT#* }
sizeB=$(printf "%d" 0x${OUT%% *})
OUT=${OUT#* }
offsetB=$(printf "%d" 0x${OUT%% *})
run_size=$(( $offsetA + $sizeA + $sizeB ))
# BFD linker shows the same file offset in ELF.
if [ "$offsetA" -ne "$offsetB" ] ; then
# Gold linker shows them as consecutive.
endB=$(( $offsetB + $sizeB ))
if [ "$endB" != "$run_size" ] ; then
printf "sizeA: 0x%x\n" $sizeA >&2
printf "offsetA: 0x%x\n" $offsetA >&2
printf "sizeB: 0x%x\n" $sizeB >&2
printf "offsetB: 0x%x\n" $offsetB >&2
echo ".bss and .brk are non-contiguous" >&2
exit 1
fi
fi
printf "%d\n" $run_size
exit 0