cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 1 | #!/usr/bin/env perl |
| 2 | use strict; |
| 3 | use warnings; |
| 4 | |
| 5 | ###################################################### |
| 6 | # Binary search script for switchback |
| 7 | # Finds bad basic block for seg faults and bad output. |
| 8 | # |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 9 | # To test output, you need to create test_ref |
| 10 | # test_ref should hold the correct output for running the test_xxx program: |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 11 | # - Everything between (not including) /^---START---$/ and /^---STOP---$/ |
| 12 | # - But NOT including output from /^---begin SWITCHBACK/ |
| 13 | # to /^--- end SWITCHBACK/ inclusive |
| 14 | # |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 15 | # This script can't handle other vex output, |
| 16 | # so e.g switchback.c::DEBUG_TRACE_FLAGS should be 0 |
| 17 | # |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 18 | |
| 19 | ###################################################### |
| 20 | # Global consts, vars |
| 21 | use constant DEBUG => 0; |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 22 | use constant CONST_N_MAX => 10000000000; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 23 | use constant CONST_N_MUL => 2; |
| 24 | |
| 25 | my $SWITCHBACK = "./switchback"; |
| 26 | my $N_START = 0; |
| 27 | my $N_LAST_GOOD = 0; |
| 28 | my $N_LAST_BAD = -1; |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 29 | my $GIVEN_LAST_GOOD = -1; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 30 | my $GIVEN_LAST_BAD = -1; |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 31 | my $TEST_REF; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 32 | |
| 33 | |
| 34 | |
| 35 | ###################################################### |
| 36 | # Helper functions |
| 37 | |
| 38 | sub Exit { |
| 39 | exit $_[0]; |
| 40 | } |
| 41 | |
| 42 | sub Usage { |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 43 | print "Usage: binary_switchback.pl test_ref [last_good [last_bad]]\n"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 44 | print "where:\n"; |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 45 | print " test_ref = reference output from test_xxx\n"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 46 | print " last_good = last known good bb (search space minimum)\n"; |
| 47 | print " last_bad = last known bad bb (search space maximum)\n"; |
| 48 | print "\n"; |
| 49 | } |
| 50 | |
| 51 | sub QuitUsage { |
| 52 | print $_[0]."\n"; |
| 53 | Usage(); |
| 54 | Exit 1; |
| 55 | } |
| 56 | |
| 57 | |
| 58 | ###################################################### |
| 59 | # Get & check cmdline args |
| 60 | # - if given, override global vars. |
| 61 | |
| 62 | if (@ARGV < 1 || @ARGV > 3) { |
| 63 | QuitUsage "Error: Bad num args\n"; |
| 64 | } |
| 65 | |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 66 | $TEST_REF = $ARGV[0]; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 67 | |
| 68 | if ( ! -x "$SWITCHBACK" ) { |
| 69 | QuitUsage "File doesn't exist | not executable: '$SWITCHBACK'\n"; |
| 70 | } |
| 71 | |
| 72 | if (@ARGV >1) { |
| 73 | $N_LAST_GOOD = $ARGV[1]; |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 74 | $GIVEN_LAST_GOOD = $N_LAST_GOOD; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 75 | if (! ($N_LAST_GOOD =~ /^\d*$/)) { |
| 76 | QuitUsage "Error: bad arg for #last_good\n"; |
| 77 | } |
| 78 | if ($N_LAST_GOOD >= CONST_N_MAX) { |
| 79 | QuitUsage "Error: #last_good >= N_MAX(".CONST_N_MAX.")\n"; |
| 80 | } |
| 81 | } |
| 82 | if (@ARGV >2) { |
| 83 | $N_LAST_BAD = $ARGV[2]; |
| 84 | $GIVEN_LAST_BAD = $N_LAST_BAD; |
| 85 | if (! ($N_LAST_BAD =~ /^\d*$/)) { |
| 86 | QuitUsage "Error: bad arg for 'last_bad'\n"; |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | # Setup N_START |
| 91 | if ($N_LAST_BAD != -1) { |
| 92 | # Start halfway: |
| 93 | my $diff = $N_LAST_BAD - $N_LAST_GOOD; |
| 94 | $N_START = $N_LAST_GOOD + ($diff - ($diff % 2)) / 2; |
| 95 | } else { |
| 96 | # No known end: Start at beginning: |
| 97 | if ($N_LAST_GOOD > 0) { # User-given last_good |
| 98 | $N_START = $N_LAST_GOOD; |
| 99 | } else { |
| 100 | $N_START = 100; # Some reasonable number. |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | ###################################################### |
| 105 | # Sanity checks (shouldn't ever happen) |
| 106 | |
| 107 | if ($N_START < $N_LAST_GOOD) { |
| 108 | print "Program Error: start < last_good\n"; |
| 109 | exit 1; |
| 110 | } |
| 111 | if ($N_LAST_BAD != -1 && $N_START >= $N_LAST_BAD) { |
| 112 | print "Program Error: start >= last_bad\n"; |
| 113 | exit 1; |
| 114 | } |
| 115 | if ($N_START < 1 || $N_START > CONST_N_MAX) { |
| 116 | print "Program Error: Bad N_START: '$N_START'\n"; |
| 117 | exit 1; |
| 118 | } |
| 119 | if ($N_LAST_GOOD < 0 || $N_LAST_GOOD > CONST_N_MAX) { |
| 120 | print "Program Error: Bad N_LAST_GOOD: '$N_LAST_GOOD'\n"; |
| 121 | exit 1; |
| 122 | } |
| 123 | if ($N_LAST_BAD < -1 || $N_LAST_BAD > CONST_N_MAX) { |
| 124 | print "Program Error: Bad N_LAST_BAD: '$N_LAST_BAD'\n"; |
| 125 | exit 1; |
| 126 | } |
| 127 | |
| 128 | |
| 129 | |
| 130 | |
| 131 | |
| 132 | |
| 133 | ###################################################### |
| 134 | # Helper functions |
| 135 | |
| 136 | # Run switchback for test, for N bbs |
| 137 | # returns output results |
| 138 | sub SwitchBack { |
| 139 | my $n = $_[0]; |
| 140 | if ($n < 0 || $n > CONST_N_MAX) { |
| 141 | print "Error SwitchBack: Bad N: '$n'\n"; |
| 142 | Exit 1; |
| 143 | } |
| 144 | my $TMPFILE = ".switchback_output.$n"; |
| 145 | |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 146 | print "=== Calling switchback for bb $n ===\n"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 147 | |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 148 | system("$SWITCHBACK $n >& $TMPFILE"); |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 149 | my $ret = $?; |
| 150 | |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 151 | if ($ret == 256) { |
| 152 | print "Error running switchback - Quitting...\n---\n"; |
| 153 | open(INFILE, "$TMPFILE"); |
| 154 | print <INFILE>; |
| 155 | close(INFILE); |
| 156 | |
| 157 | unlink($TMPFILE) if (! DEBUG); |
| 158 | exit 0; |
| 159 | } |
| 160 | |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 161 | if ($ret & 127) { |
| 162 | print "Ctrl-C pressed - Quitting...\n"; |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 163 | unlink($TMPFILE) if (! DEBUG); |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 164 | exit 0; |
| 165 | } |
| 166 | |
| 167 | if (DEBUG) { |
| 168 | if ($ret == -1) { |
| 169 | print "failed to execute: $!\n"; |
| 170 | } |
| 171 | elsif ($ret & 127) { |
| 172 | printf "child died with signal %d, %s coredump\n", |
| 173 | ($ret & 127), ($ret & 128) ? 'with' : 'without'; |
| 174 | } |
| 175 | else { |
| 176 | printf "child exited with value %d\n", $ret >> 8; |
| 177 | } |
| 178 | } |
| 179 | if ($ret != 0) { # Err: maybe seg fault |
cerion | 997661a | 2005-03-03 04:49:09 +0000 | [diff] [blame] | 180 | open(INFILE, "$TMPFILE"); |
| 181 | my @results = <INFILE>; |
| 182 | close(INFILE); |
| 183 | |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 184 | while (@results && !((shift @results) =~ /^---START---/)) {} |
cerion | 997661a | 2005-03-03 04:49:09 +0000 | [diff] [blame] | 185 | print @results; |
| 186 | |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 187 | unlink($TMPFILE) if (! DEBUG); |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 188 | return; |
| 189 | } |
| 190 | |
| 191 | open(INFILE, "$TMPFILE"); |
| 192 | my @results = <INFILE>; |
| 193 | close(INFILE); |
| 194 | |
cerion | fa09ac5 | 2005-03-04 14:20:14 +0000 | [diff] [blame] | 195 | unlink($TMPFILE) if (! DEBUG); |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 196 | return @results; |
| 197 | } |
| 198 | |
| 199 | # Returns N simulated bbs from output lines |
| 200 | sub get_N_simulated { |
| 201 | my @lines = @{$_[0]}; |
| 202 | pop @lines; # not the first... |
| 203 | my $line = pop @lines; # ...but the second line. |
| 204 | |
| 205 | chomp $line; |
| 206 | my $n; |
| 207 | if (($n) = ($line =~ /^(\d*) bbs simulated$/)) { |
| 208 | return $n; |
| 209 | } |
| 210 | print "Error: Didn't find N bbs simultated, from output lines\n"; |
| 211 | Exit 1; |
| 212 | } |
| 213 | |
| 214 | # Calls test script to compare current output lines with a reference. |
| 215 | # Returns 1 on success, 0 on failure |
| 216 | sub TestOutput { |
| 217 | my @lines = @{$_[0]}; |
| 218 | my $n = $_[1]; |
cerion | 6ded389 | 2005-12-13 21:30:48 +0000 | [diff] [blame] | 219 | my $ref_output = "$TEST_REF"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 220 | |
| 221 | # Get the current section we want to compare: |
| 222 | my @newlines; |
| 223 | my $ok=0; |
| 224 | my $halfline = ""; |
| 225 | foreach my $line(@lines) { |
| 226 | chomp $line; |
| 227 | if ($line =~ /^---STOP---$/) { last; } # we're done |
| 228 | |
| 229 | # output might be messed up here... |
| 230 | if ($line =~ /^.*---begin SWITCHBACK/) { |
| 231 | ($halfline) = ($line =~ /^(.*)---begin SWITCHBACK/); |
| 232 | $ok = 0; # stop on prev line |
| 233 | } |
| 234 | |
| 235 | # A valid line: |
| 236 | if ($ok) { |
| 237 | if ($halfline ne "") { # Fix broken line |
| 238 | $line = $halfline.$line; |
| 239 | $halfline = ""; |
| 240 | } |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 241 | |
| 242 | # Ignore Vex output |
| 243 | if ($line =~ /^vex /) { next; } |
| 244 | |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 245 | push(@newlines, $line); |
| 246 | } |
| 247 | |
| 248 | if ($line =~ /^---START---$/) { # start on next line |
| 249 | $ok = 1; |
| 250 | } |
| 251 | |
| 252 | if ($line =~ /^--- end SWITCHBACK/) { # start on next line |
| 253 | $ok = 1; |
| 254 | |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | if (DEBUG) { |
| 259 | open(OUTFILE, ">.filtered_output.$n"); |
| 260 | print OUTFILE join("\n",@newlines); |
| 261 | close(OUTFILE); |
| 262 | } |
| 263 | |
| 264 | # Read in reference lines |
| 265 | open(REFERENCE, "$ref_output") || die "Error: Couldn't open $ref_output\n"; |
| 266 | my @ref_lines = <REFERENCE>; |
| 267 | close(REFERENCE); |
| 268 | |
| 269 | # Compare reference lines with current: |
| 270 | my $match = 1; |
| 271 | my $i = 0; |
| 272 | foreach my $ref_line(@ref_lines) { |
| 273 | chomp $ref_line; |
| 274 | my $line = $newlines[$i++]; |
| 275 | chomp $line; |
| 276 | if ($ref_line ne $line) { |
| 277 | print "\nMismatch on output:\n"; |
| 278 | print "ref: '$ref_line'\n"; |
| 279 | print "new: '$line'\n\n"; |
| 280 | $match = 0; |
| 281 | last; |
| 282 | } |
| 283 | } |
| 284 | return $match; |
| 285 | } |
| 286 | |
| 287 | |
| 288 | |
| 289 | |
| 290 | |
| 291 | |
| 292 | ###################################################### |
| 293 | # Do the search |
| 294 | |
| 295 | if (DEBUG) { |
| 296 | print "\n------------\n"; |
| 297 | print "START: N=$N_START\n"; |
| 298 | print "START: lg=$N_LAST_GOOD\n"; |
| 299 | print "START: lb=$N_LAST_BAD\n"; |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 300 | print "START: GIVEN_LAST_GOOD=$GIVEN_LAST_GOOD\n"; |
| 301 | print "START: GIVEN_LAST_BAD =$GIVEN_LAST_BAD\n"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 302 | print "\n"; |
| 303 | } |
| 304 | |
| 305 | my $N = $N_START; |
| 306 | my $success = 0; |
| 307 | my @sb_output; |
| 308 | while (1) { |
| 309 | if (DEBUG) { |
| 310 | print "\n------------\n"; |
| 311 | print "SOL: lg=$N_LAST_GOOD\n"; |
| 312 | print "SOL: lb=$N_LAST_BAD\n"; |
| 313 | print "SOL: N=$N\n"; |
| 314 | } |
| 315 | if ($N < 0) { |
| 316 | print "Error: $N<0\n"; |
| 317 | Exit 1; |
| 318 | } |
| 319 | |
| 320 | my $ok = 1; |
| 321 | # Run switchback: |
| 322 | @sb_output = SwitchBack($N); |
| 323 | |
| 324 | if (@sb_output == 0) { # Switchback failed - maybe seg fault |
| 325 | $ok = 0; |
| 326 | } |
| 327 | |
| 328 | if (DEBUG) { |
| 329 | open(fileOUT, ">.retrieved_output.$N") or die("Can't open file for writing: $!"); |
| 330 | print fileOUT @sb_output; |
| 331 | close(fileOUT); |
| 332 | } |
| 333 | |
| 334 | # If we're ok so far (no seg faults) then test for correct output |
| 335 | if ($ok) { |
| 336 | $ok = TestOutput( \@sb_output, $N ); |
| 337 | } |
| 338 | |
| 339 | if ($ok) { |
| 340 | if (get_N_simulated(\@sb_output) < $N) { # Done: No bad bbs |
| 341 | $success = 1; |
| 342 | last; |
| 343 | } |
| 344 | if ($N_LAST_BAD == -1) { |
| 345 | # No upper bound for search space |
| 346 | # Try again with a bigger N |
| 347 | |
| 348 | $N_LAST_GOOD = $N; |
| 349 | $N *= CONST_N_MUL; |
| 350 | if ($N > CONST_N_MAX) { |
| 351 | print "\nError: Maxed out N($N): N_MAX=".CONST_N_MAX."\n"; |
| 352 | print "\nWe're either in a loop, or this is a big test program (increase N_MAX)\n\n"; |
| 353 | Exit 1; |
| 354 | } |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 355 | if (DEBUG) { |
| 356 | print "Looks good so far: Trying bigger N...\n\n"; |
| 357 | } |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 358 | next; |
| 359 | } |
| 360 | } |
| 361 | |
| 362 | # Narrow the search space: |
| 363 | if ($ok) { $N_LAST_GOOD = $N; } |
| 364 | else { $N_LAST_BAD = $N; } |
| 365 | |
| 366 | # Calculate next step: |
| 367 | my $diff = $N_LAST_BAD - $N_LAST_GOOD; |
| 368 | $diff = $diff - ($diff % 2); |
| 369 | my $step = $diff / 2; |
| 370 | |
| 371 | if ($step < 0) { |
| 372 | print "Error: step = $step\n"; |
| 373 | Exit 1; |
| 374 | } |
| 375 | |
| 376 | # This our last run-through? |
| 377 | if ($step!=0) { |
| 378 | $N = $N_LAST_GOOD + $step; # Keep on going... |
| 379 | } else { |
| 380 | last; # Get outta here |
| 381 | } |
| 382 | |
| 383 | if (DEBUG) { |
| 384 | print "\nEOL: ok=$ok\n"; |
| 385 | print "EOL: lg=$N_LAST_GOOD\n"; |
| 386 | print "EOL: lb=$N_LAST_BAD\n"; |
| 387 | print "EOL: s=$step\n"; |
| 388 | print "EOL: N=$N\n"; |
| 389 | } |
| 390 | } |
| 391 | |
| 392 | |
| 393 | |
| 394 | ###################################################### |
| 395 | # Done: Report results |
| 396 | |
| 397 | print "\n============================================\n"; |
| 398 | print "Done searching.\n\n"; |
| 399 | |
| 400 | if ($N_LAST_BAD != -1 && $N != $N_LAST_BAD) { |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 401 | print "Getting output for last bad bb:\n"; |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 402 | @sb_output = SwitchBack($N_LAST_BAD); |
| 403 | } |
| 404 | |
| 405 | print @sb_output; |
| 406 | print "\n\n"; |
| 407 | if ($success) { |
| 408 | print "*** Success! No bad bbs found. ***\n"; |
| 409 | } else { |
| 410 | if ($N_LAST_BAD == $GIVEN_LAST_BAD) { |
| 411 | print "*** No failures detected within given bb range ***\n"; |
| 412 | print " - check given 'last_bad' argument\n"; |
| 413 | } else { |
cerion | 87ae783 | 2005-03-01 20:31:53 +0000 | [diff] [blame] | 414 | if ($N_LAST_BAD == $GIVEN_LAST_GOOD) { |
| 415 | print "*** Failed on bb given as last_good ***\n"; |
| 416 | print " - decrease the 'last_good' argument\n"; |
| 417 | } else { |
| 418 | print "*** Failure: Last failed switchback bb: $N_LAST_BAD ***\n"; |
| 419 | print "Hence bad bb: ". ($N_LAST_BAD - 1) ."\n"; |
| 420 | } |
cerion | ab2e191 | 2005-02-28 18:48:27 +0000 | [diff] [blame] | 421 | } |
| 422 | } |
| 423 | print "\n"; |
| 424 | if (DEBUG) { |
| 425 | print "END: N=$N\n"; |
| 426 | print "END: lg=$N_LAST_GOOD\n"; |
| 427 | print "END: lb=$N_LAST_BAD\n"; |
| 428 | print "END: GIVEN_LAST_BAD=$GIVEN_LAST_BAD\n"; |
| 429 | print "\n"; |
| 430 | } |
| 431 | Exit 0; |