[yaml2obj/obj2yaml] - Add support for .stack_sizes sections.
[llvm-complete.git] / utils / findoptdiff
blob9a8803184384e444a9f3e659ca3ec36a41bfbda7
1 #!/bin/bash
3 # findoptdiff
5 # This script helps find the optimization difference between two llvm
6 # builds. It is useful when you have a build that is known to work and
7 # one that exhibits an optimization problem. Identifying the difference
8 # between the two builds can lead to discovery of the source of a
9 # mis-optimization.
11 # The script takes two llvm build paths as arguments. These specify the
12 # the two llvm builds to compare. It is generally expected that they
13 # are "close cousins". That is, they are the same except that the
14 # second build contains some experimental optimization features that
15 # are suspected of producing a misoptimization.
17 # The script takes two bitcode files, one from each build. They are
18 # presumed to be a compilation of the same program or program fragment
19 # with the only difference being the builds.
21 # The script operates by iteratively applying the optimizations that gccas
22 # and gccld run until there is a difference in the assembly resulting
23 # from the optimization. The difference is then reported with the set of
24 # optimization passes that produce the difference. The processing
25 # continues until all optimization passes have been tried. The differences
26 # for each pass, if they do differ, are placed in a diffs.# file.
28 # To work around differences in the assembly language format, the script
29 # can also take two filter arguments that post-process the assembly
30 # so they can be differenced without making false positives for known
31 # differences in the two builds. These filters are optional.
33 # Usage:
34 # findoptdiff llvm1 llvm2 bc1 bc2 filter1 filter2
36 # Where:
37 # llvm1
38 # is the path to the first llvm build dir
39 # llvm2
40 # is the path to the second llvm build dir
41 # bc1
42 # is the bitcode file for the first llvm environment
43 # bc2
44 # is the bitcode file for the second llvm environment
45 # filter1
46 # is an optional filter for filtering the llvm1 generated assembly
47 # filter2
48 # is an optional filter for filtering the llvm2 generated assembly
50 llvm1=$1
51 llvm2=$2
52 bc1=$3
53 bc2=$4
54 filt1=$5
55 filt2=$6
56 if [ -z "$filt1" ] ; then
57 filt1="cat"
59 if [ -z "$filt2" ] ; then
60 filt2="cat"
62 opt1="${bc1}.opt"
63 opt2="${bc2}.opt"
64 ll1="${bc1}.ll"
65 ll2="${bc2}.ll"
66 opt1ll="${bc1}.opt.ll"
67 opt2ll="${bc2}.opt.ll"
68 dis1="$llvm1/Debug/bin/llvm-dis"
69 dis2="$llvm2/Debug/bin/llvm-dis"
70 opt1="$llvm1/Debug/bin/opt"
71 opt2="$llvm2/Debug/bin/opt"
73 all_switches="-verify -lowersetjmp -simplifycfg -mem2reg -globalopt -globaldce -ipconstprop -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"
75 #counter=0
76 function tryit {
77 switches_to_use="$1"
78 $opt1 $switches_to_use "$bc1" -o - | $dis1 | $filt1 > "$opt1ll"
79 $opt2 $switches_to_use "$bc2" -o - | $dis2 | $filt2 > "$opt2ll"
80 diffs="diffs."$((counter++))
81 diff "$opt1ll" "$opt2ll" > $diffs
82 if [ $? -ne 0 ] ; then
83 echo
84 echo "Diff fails with these switches:"
85 echo $switches
86 echo "Differences:"
87 head $diffs
88 echo 'Switches:' $switches_to_use >> $diffs
89 else
90 rm $diffs
92 return 1
95 for sw in $all_switches ; do
96 echo -n " $sw"
97 switches="$switches $sw"
98 if tryit "$switches" ; then
99 break;
101 done