102 lines
3.8 KiB
Bash
Executable File
102 lines
3.8 KiB
Bash
Executable File
#!/bin/bash
|
|
#
|
|
# findoptdiff
|
|
#
|
|
# This script helps find the optimization difference between two llvm
|
|
# builds. It is useful when you have a build that is known to work and
|
|
# one that exhibits an optimization problem. Identifying the difference
|
|
# between the two builds can lead to discovery of the source of a
|
|
# mis-optimization.
|
|
#
|
|
# The script takes two llvm build paths as arguments. These specify the
|
|
# the two llvm builds to compare. It is generally expected that they
|
|
# are "close cousins". That is, they are the same except that the
|
|
# second build contains some experimental optimization features that
|
|
# are suspected of producing a misoptimization.
|
|
#
|
|
# The script takes two bitcode files, one from each build. They are
|
|
# presumed to be a compilation of the same program or program fragment
|
|
# with the only difference being the builds.
|
|
#
|
|
# The script operates by iteratively applying the optimizations that gccas
|
|
# and gccld run until there is a difference in the assembly resulting
|
|
# from the optimization. The difference is then reported with the set of
|
|
# optimization passes that produce the difference. The processing
|
|
# continues until all optimization passes have been tried. The differences
|
|
# for each pass, if they do differ, are placed in a diffs.# file.
|
|
#
|
|
# To work around differences in the assembly language format, the script
|
|
# can also take two filter arguments that post-process the assembly
|
|
# so they can be differenced without making false positives for known
|
|
# differences in the two builds. These filters are optional.
|
|
#
|
|
# Usage:
|
|
# findoptdiff llvm1 llvm2 bc1 bc2 filter1 filter2
|
|
#
|
|
# Where:
|
|
# llvm1
|
|
# is the path to the first llvm build dir
|
|
# llvm2
|
|
# is the path to the second llvm build dir
|
|
# bc1
|
|
# is the bitcode file for the first llvm environment
|
|
# bc2
|
|
# is the bitcode file for the second llvm environment
|
|
# filter1
|
|
# is an optional filter for filtering the llvm1 generated assembly
|
|
# filter2
|
|
# is an optional filter for filtering the llvm2 generated assembly
|
|
#
|
|
llvm1=$1
|
|
llvm2=$2
|
|
bc1=$3
|
|
bc2=$4
|
|
filt1=$5
|
|
filt2=$6
|
|
if [ -z "$filt1" ] ; then
|
|
filt1="cat"
|
|
fi
|
|
if [ -z "$filt2" ] ; then
|
|
filt2="cat"
|
|
fi
|
|
opt1="${bc1}.opt"
|
|
opt2="${bc2}.opt"
|
|
ll1="${bc1}.ll"
|
|
ll2="${bc2}.ll"
|
|
opt1ll="${bc1}.opt.ll"
|
|
opt2ll="${bc2}.opt.ll"
|
|
dis1="$llvm1/Debug/bin/llvm-dis"
|
|
dis2="$llvm2/Debug/bin/llvm-dis"
|
|
opt1="$llvm1/Debug/bin/opt"
|
|
opt2="$llvm2/Debug/bin/opt"
|
|
|
|
all_switches="-verify -lowersetjmp -simplifycfg -mem2reg -globalopt -globaldce -deadargelim -instcombine -simplifycfg -prune-eh -inline -simplify-libcalls -argpromotion -tailduplicate -simplifycfg -sroa -instcombine -predsimplify -condprop -tailcallelim -simplifycfg -reassociate -licm -loop-unswitch -instcombine -indvars -loop-unroll -instcombine -load-vn -gcse -sccp -instcombine -condprop -dse -dce -simplifycfg -deadtypeelim -constmerge -internalize -ipsccp -globalopt -constmerge -deadargelim -inline -prune-eh -globalopt -globaldce -argpromotion -instcombine -predsimplify -sroa -globalsmodref-aa -licm -load-vn -gcse -dse -instcombine -simplifycfg -verify"
|
|
|
|
#counter=0
|
|
function tryit {
|
|
switches_to_use="$1"
|
|
$opt1 $switches_to_use "$bc1" -o - | $dis1 | $filt1 > "$opt1ll"
|
|
$opt2 $switches_to_use "$bc2" -o - | $dis2 | $filt2 > "$opt2ll"
|
|
diffs="diffs."$((counter++))
|
|
diff "$opt1ll" "$opt2ll" > $diffs
|
|
if [ $? -ne 0 ] ; then
|
|
echo
|
|
echo "Diff fails with these switches:"
|
|
echo $switches
|
|
echo "Differences:"
|
|
head $diffs
|
|
echo 'Switches:' $switches_to_use >> $diffs
|
|
else
|
|
rm $diffs
|
|
fi
|
|
return 1
|
|
}
|
|
|
|
for sw in $all_switches ; do
|
|
echo -n " $sw"
|
|
switches="$switches $sw"
|
|
if tryit "$switches" ; then
|
|
break;
|
|
fi
|
|
done
|