gcc/params.def

   1 /* params.def - Run-time parameters.
   2    Copyright (C) 2001-2016 Free Software Foundation, Inc.
   3    Written by Mark Mitchell <mark@codesourcery.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 /* This file contains definitions for language-independent
  22    parameters.  The DEFPARAM macro takes 6 arguments:
  23
  24      - The enumeral corresponding to this parameter.
  25
  26      - The name that can be used to set this parameter using the
  27        command-line option `--param <name>=<value>'.
  28
  29      - A help string explaining how the parameter is used.
  30
  31      - A default value for the parameter.
  32
  33      - The minimum acceptable value for the parameter.
  34
  35      - The maximum acceptable value for the parameter (if greater than
  36      the minimum).
  37
  38    The DEFPARAMENUM<N> macro is similar, but instead of the minumum and maximum
  39    arguments, it contains a list of <N> allowed strings, corresponding to
  40    integer values 0..<N>-1.  Note that the default argument needs to be
  41    specified as one of the allowed strings, rather than an integer value.
  42
  43    Be sure to add an entry to invoke.texi summarizing the parameter.  */
  44
  45 /* When branch is predicted to be taken with probability lower than this
  46    threshold (in percent), then it is considered well predictable. */
  47 DEFPARAM (PARAM_PREDICTABLE_BRANCH_OUTCOME,
  48           "predictable-branch-outcome",
  49           "Maximal estimated outcome of branch considered predictable.",
  50           2, 0, 50)
  51
  52 DEFPARAM (PARAM_INLINE_MIN_SPEEDUP,
  53           "inline-min-speedup",
  54           "The minimal estimated speedup allowing inliner to ignore inline-insns-single and inline-isnsns-auto.",
  55           10, 0, 0)
  56
  57 /* The single function inlining limit. This is the maximum size
  58    of a function counted in internal gcc instructions (not in
  59    real machine instructions) that is eligible for inlining
  60    by the tree inliner.
  61    The default value is 450.
  62    Only functions marked inline (or methods defined in the class
  63    definition for C++) are affected by this.
  64    There are more restrictions to inlining: If inlined functions
  65    call other functions, the already inlined instructions are
  66    counted and once the recursive inline limit (see
  67    "max-inline-insns" parameter) is exceeded, the acceptable size
  68    gets decreased.  */
  69 DEFPARAM (PARAM_MAX_INLINE_INSNS_SINGLE,
  70           "max-inline-insns-single",
  71           "The maximum number of instructions in a single function eligible for inlining.",
  72           400, 0, 0)
  73
  74 /* The single function inlining limit for functions that are
  75    inlined by virtue of -finline-functions (-O3).
  76    This limit should be chosen to be below or equal to the limit
  77    that is applied to functions marked inlined (or defined in the
  78    class declaration in C++) given by the "max-inline-insns-single"
  79    parameter.
  80    The default value is 40.  */
  81 DEFPARAM (PARAM_MAX_INLINE_INSNS_AUTO,
  82           "max-inline-insns-auto",
  83           "The maximum number of instructions when automatically inlining.",
  84           40, 0, 0)
  85
  86 DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE,
  87           "max-inline-insns-recursive",
  88           "The maximum number of instructions inline function can grow to via recursive inlining.",
  89           450, 0, 0)
  90
  91 DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO,
  92           "max-inline-insns-recursive-auto",
  93           "The maximum number of instructions non-inline function can grow to via recursive inlining.",
  94           450, 0, 0)
  95
  96 DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH,
  97           "max-inline-recursive-depth",
  98           "The maximum depth of recursive inlining for inline functions.",
  99           8, 0, 0)
 100
 101 DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO,
 102           "max-inline-recursive-depth-auto",
 103           "The maximum depth of recursive inlining for non-inline functions.",
 104           8, 0, 0)
 105
 106 DEFPARAM (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY,
 107           "min-inline-recursive-probability",
 108           "Inline recursively only when the probability of call being executed exceeds the parameter.",
 109           10, 0, 0)
 110
 111 /* Limit of iterations of early inliner.  This basically bounds number of
 112    nested indirect calls early inliner can resolve.  Deeper chains are still
 113    handled by late inlining.  */
 114 DEFPARAM (PARAM_EARLY_INLINER_MAX_ITERATIONS,
 115           "max-early-inliner-iterations",
 116           "The maximum number of nested indirect inlining performed by early inliner.",
 117           1, 0, 0)
 118
 119 /* Limit on probability of entry BB.  */
 120 DEFPARAM (PARAM_COMDAT_SHARING_PROBABILITY,
 121           "comdat-sharing-probability",
 122           "Probability that COMDAT function will be shared with different compilation unit.",
 123           20, 0, 0)
 124
 125 /* Limit on probability of entry BB.  */
 126 DEFPARAM (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY,
 127           "partial-inlining-entry-probability",
 128           "Maximum probability of the entry BB of split region (in percent relative to entry BB of the function) to make partial inlining happen.",
 129           70, 0, 0)
 130
 131 /* Limit the number of expansions created by the variable expansion
 132    optimization to avoid register pressure.  */
 133 DEFPARAM (PARAM_MAX_VARIABLE_EXPANSIONS,
 134           "max-variable-expansions-in-unroller",
 135           "If -fvariable-expansion-in-unroller is used, the maximum number of times that an individual variable will be expanded during loop unrolling.",
 136           1, 0, 0)
 137
 138 /* Limit loop autovectorization to loops with large enough iteration count.  */
 139 DEFPARAM (PARAM_MIN_VECT_LOOP_BOUND,
 140           "min-vect-loop-bound",
 141           "If -ftree-vectorize is used, the minimal loop bound of a loop to be considered for vectorization.",
 142           1, 1, 0)
 143
 144 /* The maximum number of instructions to consider when looking for an
 145    instruction to fill a delay slot.  If more than this arbitrary
 146    number of instructions is searched, the time savings from filling
 147    the delay slot will be minimal so stop searching.  Increasing
 148    values mean more aggressive optimization, making the compile time
 149    increase with probably small improvement in executable run time.  */
 150 DEFPARAM (PARAM_MAX_DELAY_SLOT_INSN_SEARCH,
 151           "max-delay-slot-insn-search",
 152           "The maximum number of instructions to consider to fill a delay slot.",
 153           100, 0, 0)
 154
 155 /* When trying to fill delay slots, the maximum number of instructions
 156    to consider when searching for a block with valid live register
 157    information.  Increasing this arbitrarily chosen value means more
 158    aggressive optimization, increasing the compile time.  This
 159    parameter should be removed when the delay slot code is rewritten
 160    to maintain the control-flow graph.  */
 161 DEFPARAM(PARAM_MAX_DELAY_SLOT_LIVE_SEARCH,
 162          "max-delay-slot-live-search",
 163          "The maximum number of instructions to consider to find accurate live register information.",
 164          333, 0, 0)
 165
 166 /* This parameter limits the number of branch elements that the
 167    scheduler will track anti-dependencies through without resetting
 168    the tracking mechanism.  Large functions with few calls or barriers
 169    can generate lists containing many 1000's of dependencies.  Generally
 170    the compiler either uses all available memory, or runs for far too long.  */
 171 DEFPARAM(PARAM_MAX_PENDING_LIST_LENGTH,
 172          "max-pending-list-length",
 173          "The maximum length of scheduling's pending operations list.",
 174          32, 0, 0)
 175
 176 /* This parameter limits the number of backtracking attempts when using the
 177    haifa scheduler for modulo scheduling.  */
 178 DEFPARAM(PARAM_MAX_MODULO_BACKTRACK_ATTEMPTS,
 179          "max-modulo-backtrack-attempts",
 180          "The maximum number of backtrack attempts the scheduler should make when modulo scheduling a loop.",
 181          40, 0, 0)
 182
 183 DEFPARAM(PARAM_LARGE_FUNCTION_INSNS,
 184          "large-function-insns",
 185          "The size of function body to be considered large.",
 186          2700, 0, 0)
 187 DEFPARAM(PARAM_LARGE_FUNCTION_GROWTH,
 188          "large-function-growth",
 189          "Maximal growth due to inlining of large function (in percent).",
 190          100, 0, 0)
 191 DEFPARAM(PARAM_LARGE_UNIT_INSNS,
 192          "large-unit-insns",
 193          "The size of translation unit to be considered large.",
 194          10000, 0, 0)
 195 DEFPARAM(PARAM_INLINE_UNIT_GROWTH,
 196          "inline-unit-growth",
 197          "How much can given compilation unit grow because of the inlining (in percent).",
 198          20, 0, 0)
 199 DEFPARAM(PARAM_IPCP_UNIT_GROWTH,
 200          "ipcp-unit-growth",
 201          "How much can given compilation unit grow because of the interprocedural constant propagation (in percent).",
 202          10, 0, 0)
 203 DEFPARAM(PARAM_EARLY_INLINING_INSNS,
 204          "early-inlining-insns",
 205          "Maximal estimated growth of function body caused by early inlining of single call.",
 206          14, 0, 0)
 207 DEFPARAM(PARAM_LARGE_STACK_FRAME,
 208          "large-stack-frame",
 209          "The size of stack frame to be considered large.",
 210          256, 0, 0)
 211 DEFPARAM(PARAM_STACK_FRAME_GROWTH,
 212          "large-stack-frame-growth",
 213          "Maximal stack frame growth due to inlining (in percent).",
 214          1000, 0, 0)
 215
 216 /* The GCSE optimization will be disabled if it would require
 217    significantly more memory than this value.  */
 218 DEFPARAM(PARAM_MAX_GCSE_MEMORY,
 219          "max-gcse-memory",
 220          "The maximum amount of memory to be allocated by GCSE.",
 221          128 * 1024 * 1024, 0, 0)
 222
 223 /* The GCSE optimization of an expression will avoided if the ratio of
 224    insertions to deletions is greater than this value.  */
 225 DEFPARAM(PARAM_MAX_GCSE_INSERTION_RATIO,
 226          "max-gcse-insertion-ratio",
 227          "The maximum ratio of insertions to deletions of expressions in GCSE.",
 228          20, 0, 0)
 229
 230 /* This is the threshold ratio when to perform partial redundancy
 231    elimination after reload. We perform partial redundancy elimination
 232    when the following holds:
 233    (Redundant load execution count)
 234    ------------------------------- >= GCSE_AFTER_RELOAD_PARTIAL_FRACTION
 235    (Added loads execution count)                                          */
 236 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_PARTIAL_FRACTION,
 237         "gcse-after-reload-partial-fraction",
 238         "The threshold ratio for performing partial redundancy elimination after reload.",
 239         3, 0, 0)
 240 /* This is the threshold ratio of the critical edges execution count compared to
 241    the redundant loads execution count that permits performing the load
 242    redundancy elimination in gcse after reload.  */
 243 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_CRITICAL_FRACTION,
 244         "gcse-after-reload-critical-fraction",
 245         "The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload.",
 246         10, 0, 0)
 247
 248 /* GCSE will use GCSE_COST_DISTANCE_RATION as a scaling factor
 249    to calculate maximum distance for which an expression is allowed to move
 250    from its rtx_cost.  */
 251 DEFPARAM(PARAM_GCSE_COST_DISTANCE_RATIO,
 252          "gcse-cost-distance-ratio",
 253          "Scaling factor in calculation of maximum distance an expression can be moved by GCSE optimizations.",
 254          10, 0, 0)
 255 /* GCSE won't restrict distance for which an expression with rtx_cost greater
 256    than COSTS_N_INSN(GCSE_UNRESTRICTED_COST) is allowed to move.  */
 257 DEFPARAM(PARAM_GCSE_UNRESTRICTED_COST,
 258          "gcse-unrestricted-cost",
 259          "Cost at which GCSE optimizations will not constraint the distance an expression can travel.",
 260          3, 0, 0)
 261
 262 /* How deep from a given basic block the dominator tree should be searched
 263    for expressions to hoist to the block.  The value of 0 will avoid limiting
 264    the search.  */
 265 DEFPARAM(PARAM_MAX_HOIST_DEPTH,
 266          "max-hoist-depth",
 267          "Maximum depth of search in the dominator tree for expressions to hoist.",
 268          30, 0, 0)
 269
 270
 271 /* When synthesizing expnonentiation by a real constant operations using square
 272    roots, this controls how deep sqrt chains we are willing to generate.  */
 273 DEFPARAM(PARAM_MAX_POW_SQRT_DEPTH,
 274          "max-pow-sqrt-depth",
 275          "Maximum depth of sqrt chains to use when synthesizing exponentiation by a real constant.",
 276          5, 1, 32)
 277
 278 /* This parameter limits the number of insns in a loop that will be unrolled,
 279    and by how much the loop is unrolled.
 280
 281    This limit should be at most half of the peeling limits:  loop unroller
 282    decides to not unroll loops that iterate fewer than 2*number of allowed
 283    unrollings and thus we would have loops that are neither peeled or unrolled
 284    otherwise.  */
 285 DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
 286          "max-unrolled-insns",
 287          "The maximum number of instructions to consider to unroll in a loop.",
 288          200, 0, 0)
 289 /* This parameter limits how many times the loop is unrolled depending
 290    on number of insns really executed in each iteration.  */
 291 DEFPARAM(PARAM_MAX_AVERAGE_UNROLLED_INSNS,
 292          "max-average-unrolled-insns",
 293          "The maximum number of instructions to consider to unroll in a loop on average.",
 294          80, 0, 0)
 295 /* The maximum number of unrollings of a single loop.  */
 296 DEFPARAM(PARAM_MAX_UNROLL_TIMES,
 297         "max-unroll-times",
 298         "The maximum number of unrollings of a single loop.",
 299         8, 0, 0)
 300 /* The maximum number of insns of a peeled loop.  */
 301 DEFPARAM(PARAM_MAX_PEELED_INSNS,
 302         "max-peeled-insns",
 303         "The maximum number of insns of a peeled loop.",
 304         100, 0, 0)
 305 /* The maximum number of peelings of a single loop.  */
 306 DEFPARAM(PARAM_MAX_PEEL_TIMES,
 307         "max-peel-times",
 308         "The maximum number of peelings of a single loop.",
 309         16, 0, 0)
 310 /* The maximum number of peelings of a single loop that is peeled completely.  */
 311 DEFPARAM(PARAM_MAX_PEEL_BRANCHES,
 312         "max-peel-branches",
 313         "The maximum number of branches on the path through the peeled sequence.",
 314         32, 0, 0)
 315 /* The maximum number of insns of a peeled loop.  */
 316 DEFPARAM(PARAM_MAX_COMPLETELY_PEELED_INSNS,
 317         "max-completely-peeled-insns",
 318         "The maximum number of insns of a completely peeled loop.",
 319         200, 0, 0)
 320 /* The maximum number of peelings of a single loop that is peeled completely.  */
 321 DEFPARAM(PARAM_MAX_COMPLETELY_PEEL_TIMES,
 322         "max-completely-peel-times",
 323         "The maximum number of peelings of a single loop that is peeled completely.",
 324         16, 0, 0)
 325 /* The maximum number of insns of a peeled loop that rolls only once.  */
 326 DEFPARAM(PARAM_MAX_ONCE_PEELED_INSNS,
 327         "max-once-peeled-insns",
 328         "The maximum number of insns of a peeled loop that rolls only once.",
 329         400, 0, 0)
 330 /* The maximum depth of a loop nest we completely peel.  */
 331 DEFPARAM(PARAM_MAX_UNROLL_ITERATIONS,
 332          "max-completely-peel-loop-nest-depth",
 333          "The maximum depth of a loop nest we completely peel.",
 334          8, 0, 0)
 335
 336 /* The maximum number of insns of an unswitched loop.  */
 337 DEFPARAM(PARAM_MAX_UNSWITCH_INSNS,
 338         "max-unswitch-insns",
 339         "The maximum number of insns of an unswitched loop.",
 340         50, 0, 0)
 341 /* The maximum level of recursion in unswitch_single_loop.  */
 342 DEFPARAM(PARAM_MAX_UNSWITCH_LEVEL,
 343         "max-unswitch-level",
 344         "The maximum number of unswitchings in a single loop.",
 345         3, 0, 0)
 346
 347 /* The maximum number of insns in loop header duplicated by he copy loop
 348    headers pass.  */
 349 DEFPARAM(PARAM_MAX_LOOP_HEADER_INSNS,
 350         "max-loop-header-insns",
 351         "The maximum number of insns in loop header duplicated by he copy loop headers pass.",
 352         20, 0, 0)
 353
 354 /* The maximum number of iterations of a loop the brute force algorithm
 355    for analysis of # of iterations of the loop tries to evaluate.  */
 356 DEFPARAM(PARAM_MAX_ITERATIONS_TO_TRACK,
 357         "max-iterations-to-track",
 358         "Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates.",
 359         1000, 0, 0)
 360 /* A cutoff to avoid costly computations of the number of iterations in
 361    the doloop transformation.  */
 362 DEFPARAM(PARAM_MAX_ITERATIONS_COMPUTATION_COST,
 363         "max-iterations-computation-cost",
 364         "Bound on the cost of an expression to compute the number of iterations.",
 365         10, 0, 0)
 366
 367 /* This parameter is used to tune SMS MAX II calculations.  */
 368 DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
 369          "sms-max-ii-factor",
 370          "A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop.",
 371          100, 0, 0)
 372 /* The minimum value of stage count that swing modulo scheduler will generate.  */
 373 DEFPARAM(PARAM_SMS_MIN_SC,
 374         "sms-min-sc",
 375         "The minimum value of stage count that swing modulo scheduler will generate.",
 376         2, 1, 1)
 377 DEFPARAM(PARAM_SMS_DFA_HISTORY,
 378          "sms-dfa-history",
 379          "The number of cycles the swing modulo scheduler considers when checking conflicts using DFA.",
 380          0, 0, 0)
 381 DEFPARAM(PARAM_SMS_LOOP_AVERAGE_COUNT_THRESHOLD,
 382          "sms-loop-average-count-threshold",
 383          "A threshold on the average loop count considered by the swing modulo scheduler.",
 384          0, 0, 0)
 385
 386 DEFPARAM(HOT_BB_COUNT_WS_PERMILLE,
 387          "hot-bb-count-ws-permille",
 388          "A basic block profile count is considered hot if it contributes to "
 389          "the given permillage of the entire profiled execution.",
 390          999, 0, 1000)
 391 DEFPARAM(HOT_BB_FREQUENCY_FRACTION,
 392          "hot-bb-frequency-fraction",
 393          "Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot.",
 394          1000, 0, 0)
 395
 396 DEFPARAM(UNLIKELY_BB_COUNT_FRACTION,
 397          "unlikely-bb-count-fraction",
 398          "The minimum fraction of profile runs a given basic block execution count must be not to be considered unlikely.",
 399          20, 1, 10000)
 400
 401 DEFPARAM (PARAM_ALIGN_THRESHOLD,
 402           "align-threshold",
 403           "Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment.",
 404           100, 1, 0)
 405
 406 DEFPARAM (PARAM_ALIGN_LOOP_ITERATIONS,
 407           "align-loop-iterations",
 408           "Loops iterating at least selected number of iterations will get loop alignment..",
 409           4, 0, 0)
 410
 411 /* For guessed profiles, the loops having unknown number of iterations
 412    are predicted to iterate relatively few (10) times at average.
 413    For functions containing one loop with large known number of iterations
 414    and other loops having unbounded loops we would end up predicting all
 415    the other loops cold that is not usually the case.  So we need to artificially
 416    flatten the profile.
 417
 418    We need to cut the maximal predicted iterations to large enough iterations
 419    so the loop appears important, but safely within maximum hotness
 420    range.  */
 421
 422 DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
 423          "max-predicted-iterations",
 424          "The maximum number of loop iterations we predict statically.",
 425          100, 0, 0)
 426
 427 /* This parameter controls the probability of builtin_expect. The default
 428    value is 90%. This empirical value is obtained through the weighted
 429    probability of FDO counters (with the FDO count value as the weight)
 430    in some real world programs:
 431    (1) Google performance test benchmarks: the probability is 0.9081.
 432    (2) Linux 3.3 kernel running Google search workload: the probability
 433    is 0.8717.  */
 434
 435 DEFPARAM(BUILTIN_EXPECT_PROBABILITY,
 436          "builtin-expect-probability",
 437          "Set the estimated probability in percentage for builtin expect. The default value is 90% probability.",
 438          90, 0, 100)
 439 DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK,
 440          "tracer-dynamic-coverage-feedback",
 441          "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available.",
 442          95, 0, 100)
 443 DEFPARAM(TRACER_DYNAMIC_COVERAGE,
 444          "tracer-dynamic-coverage",
 445          "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available.",
 446          75, 0, 100)
 447 DEFPARAM(TRACER_MAX_CODE_GROWTH,
 448          "tracer-max-code-growth",
 449          "Maximal code growth caused by tail duplication (in percent).",
 450          100, 0, 0)
 451 DEFPARAM(TRACER_MIN_BRANCH_RATIO,
 452          "tracer-min-branch-ratio",
 453          "Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent).",
 454          10, 0, 100)
 455 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK,
 456          "tracer-min-branch-probability-feedback",
 457          "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available.",
 458          80, 0, 100)
 459 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY,
 460          "tracer-min-branch-probability",
 461          "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available.",
 462          50, 0, 100)
 463
 464 /* The maximum number of incoming edges to consider for crossjumping.  */
 465 DEFPARAM(PARAM_MAX_CROSSJUMP_EDGES,
 466          "max-crossjump-edges",
 467          "The maximum number of incoming edges to consider for crossjumping.",
 468          100, 0, 0)
 469
 470 /* The minimum number of matching instructions to consider for crossjumping.  */
 471 DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
 472      "min-crossjump-insns",
 473      "The minimum number of matching instructions to consider for crossjumping.",
 474      5, 1, 0)
 475
 476 /* The maximum number expansion factor when copying basic blocks.  */
 477 DEFPARAM(PARAM_MAX_GROW_COPY_BB_INSNS,
 478      "max-grow-copy-bb-insns",
 479      "The maximum expansion factor when copying basic blocks.",
 480      8, 0, 0)
 481
 482 /* The maximum number of insns to duplicate when unfactoring computed gotos.  */
 483 DEFPARAM(PARAM_MAX_GOTO_DUPLICATION_INSNS,
 484      "max-goto-duplication-insns",
 485      "The maximum number of insns to duplicate when unfactoring computed gotos.",
 486      8, 0, 0)
 487
 488 /* The maximum length of path considered in cse.  */
 489 DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
 490          "max-cse-path-length",
 491          "The maximum length of path considered in cse.",
 492          10, 1, 0)
 493 DEFPARAM(PARAM_MAX_CSE_INSNS,
 494          "max-cse-insns",
 495          "The maximum instructions CSE process before flushing.",
 496          1000, 0, 0)
 497
 498 /* The cost of expression in loop invariant motion that is considered
 499    expensive.  */
 500 DEFPARAM(PARAM_LIM_EXPENSIVE,
 501          "lim-expensive",
 502          "The minimum cost of an expensive expression in the loop invariant motion.",
 503          20, 0, 0)
 504
 505 /* Bound on number of candidates for induction variables below that
 506    all candidates are considered for each use in induction variable
 507    optimizations.  */
 508
 509 DEFPARAM(PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND,
 510          "iv-consider-all-candidates-bound",
 511          "Bound on number of candidates below that all candidates are considered in iv optimizations.",
 512          40, 0, 0)
 513
 514 /* The induction variable optimizations give up on loops that contain more
 515    induction variable uses.  */
 516
 517 DEFPARAM(PARAM_IV_MAX_CONSIDERED_USES,
 518          "iv-max-considered-uses",
 519          "Bound on number of iv uses in loop optimized in iv optimizations.",
 520          250, 0, 0)
 521
 522 /* If there are at most this number of ivs in the set, try removing unnecessary
 523    ivs from the set always.  */
 524
 525 DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
 526          "iv-always-prune-cand-set-bound",
 527          "If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization.",
 528          10, 0, 0)
 529
 530 DEFPARAM(PARAM_AVG_LOOP_NITER,
 531          "avg-loop-niter",
 532          "Average number of iterations of a loop.",
 533          10, 1, 0)
 534
 535 DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
 536          "scev-max-expr-size",
 537          "Bound on size of expressions used in the scalar evolutions analyzer.",
 538          100, 0, 0)
 539
 540 DEFPARAM(PARAM_SCEV_MAX_EXPR_COMPLEXITY,
 541          "scev-max-expr-complexity",
 542          "Bound on the complexity of the expressions in the scalar evolutions analyzer.",
 543          10, 0, 0)
 544
 545 DEFPARAM (PARAM_MAX_TREE_IF_CONVERSION_PHI_ARGS,
 546           "max-tree-if-conversion-phi-args",
 547           "Maximum number of arguments in a PHI supported by TREE if-conversion "
 548           "unless the loop is marked with simd pragma.",
 549           4, 2, 0)
 550
 551 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS,
 552          "vect-max-version-for-alignment-checks",
 553          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check.",
 554          6, 0, 0)
 555
 556 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS,
 557          "vect-max-version-for-alias-checks",
 558          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check.",
 559          10, 0, 0)
 560
 561 DEFPARAM(PARAM_VECT_MAX_PEELING_FOR_ALIGNMENT,
 562          "vect-max-peeling-for-alignment",
 563          "Max number of loop peels to enhancement alignment of data references in a loop.",
 564          -1, -1, 64)
 565
 566 DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
 567          "max-cselib-memory-locations",
 568          "The maximum memory locations recorded by cselib.",
 569          500, 0, 0)
 570
 571 #ifdef ENABLE_GC_ALWAYS_COLLECT
 572 # define GGC_MIN_EXPAND_DEFAULT 0
 573 # define GGC_MIN_HEAPSIZE_DEFAULT 0
 574 #else
 575 # define GGC_MIN_EXPAND_DEFAULT 30
 576 # define GGC_MIN_HEAPSIZE_DEFAULT 4096
 577 #endif
 578
 579 DEFPARAM(GGC_MIN_EXPAND,
 580          "ggc-min-expand",
 581          "Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap.",
 582          GGC_MIN_EXPAND_DEFAULT, 0, 0)
 583
 584 DEFPARAM(GGC_MIN_HEAPSIZE,
 585          "ggc-min-heapsize",
 586          "Minimum heap size before we start collecting garbage, in kilobytes.",
 587          GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
 588
 589 #undef GGC_MIN_EXPAND_DEFAULT
 590 #undef GGC_MIN_HEAPSIZE_DEFAULT
 591
 592 DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
 593          "max-reload-search-insns",
 594          "The maximum number of instructions to search backward when looking for equivalent reload.",
 595          100, 0, 0)
 596
 597 DEFPARAM(PARAM_SINK_FREQUENCY_THRESHOLD,
 598          "sink-frequency-threshold",
 599          "Target block's relative execution frequency (as a percentage) required to sink a statement.",
 600          75, 0, 100)
 601
 602 DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
 603          "max-sched-region-blocks",
 604          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 605          10, 0, 0)
 606
 607 DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
 608          "max-sched-region-insns",
 609          "The maximum number of insns in a region to be considered for interblock scheduling.",
 610          100, 0, 0)
 611
 612 DEFPARAM(PARAM_MAX_PIPELINE_REGION_BLOCKS,
 613          "max-pipeline-region-blocks",
 614          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 615          15, 0, 0)
 616
 617 DEFPARAM(PARAM_MAX_PIPELINE_REGION_INSNS,
 618          "max-pipeline-region-insns",
 619          "The maximum number of insns in a region to be considered for interblock scheduling.",
 620          200, 0, 0)
 621
 622 DEFPARAM(PARAM_MIN_SPEC_PROB,
 623          "min-spec-prob",
 624          "The minimum probability of reaching a source block for interblock speculative scheduling.",
 625          40, 0, 0)
 626
 627 DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
 628          "max-sched-extend-regions-iters",
 629          "The maximum number of iterations through CFG to extend regions.",
 630          0, 0, 0)
 631
 632 DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
 633          "max-sched-insn-conflict-delay",
 634          "The maximum conflict delay for an insn to be considered for speculative motion.",
 635          3, 1, 10)
 636
 637 DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
 638          "sched-spec-prob-cutoff",
 639          "The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
 640          40, 0, 100)
 641
 642 DEFPARAM(PARAM_SCHED_STATE_EDGE_PROB_CUTOFF,
 643          "sched-state-edge-prob-cutoff",
 644          "The minimum probability an edge must have for the scheduler to save its state across it.",
 645          10, 0, 100)
 646
 647 DEFPARAM(PARAM_SELSCHED_MAX_LOOKAHEAD,
 648          "selsched-max-lookahead",
 649          "The maximum size of the lookahead window of selective scheduling.",
 650          50, 0, 0)
 651
 652 DEFPARAM(PARAM_SELSCHED_MAX_SCHED_TIMES,
 653          "selsched-max-sched-times",
 654          "Maximum number of times that an insn could be scheduled.",
 655          2, 0, 0)
 656
 657 DEFPARAM(PARAM_SELSCHED_INSNS_TO_RENAME,
 658          "selsched-insns-to-rename",
 659          "Maximum number of instructions in the ready list that are considered eligible for renaming.",
 660          2, 0, 0)
 661
 662 DEFPARAM (PARAM_SCHED_MEM_TRUE_DEP_COST,
 663           "sched-mem-true-dep-cost",
 664           "Minimal distance between possibly conflicting store and load.",
 665           1, 0, 0)
 666
 667 DEFPARAM (PARAM_SCHED_AUTOPREF_QUEUE_DEPTH,
 668           "sched-autopref-queue-depth",
 669           "Hardware autoprefetcher scheduler model control flag.  Number of lookahead cycles the model looks into; at '0' only enable instruction sorting heuristic.  Disabled by default.",
 670           -1, 0, 0)
 671
 672 DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
 673          "max-last-value-rtl",
 674          "The maximum number of RTL nodes that can be recorded as combiner's last value.",
 675          10000, 0, 0)
 676
 677 DEFPARAM(PARAM_MAX_COMBINE_INSNS,
 678          "max-combine-insns",
 679          "The maximum number of insns combine tries to combine.",
 680          4, 2, 4)
 681
 682 /* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
 683    {signed,unsigned} integral types.  This determines N.
 684    Experimentation shows 251 to be a good value that generates the
 685    least amount of garbage for allocating the TREE_VEC storage.  */
 686 DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
 687           "integer-share-limit",
 688           "The upper bound for sharing integer constants.",
 689           251, 2, 2)
 690
 691 DEFPARAM (PARAM_SSP_BUFFER_SIZE,
 692           "ssp-buffer-size",
 693           "The lower bound for a buffer to be considered for stack smashing protection.",
 694           8, 1, 0)
 695
 696 DEFPARAM (PARAM_MIN_SIZE_FOR_STACK_SHARING,
 697           "min-size-for-stack-sharing",
 698           "The minimum size of variables taking part in stack slot sharing "
 699           "when not optimizing.",
 700           32, 0, 0)
 701
 702 /* When we thread through a block we have to make copies of the
 703    statements within the block.  Clearly for large blocks the code
 704    duplication is bad.
 705
 706    PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
 707    of statements and PHI nodes allowed in a block which is going to
 708    be duplicated for thread jumping purposes.
 709
 710    Some simple analysis showed that more than 99% of the jump
 711    threading opportunities are for blocks with less than 15
 712    statements.  So we can get the benefits of jump threading
 713    without excessive code bloat for pathological cases with the
 714    throttle set at 15 statements.  */
 715 DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
 716           "max-jump-thread-duplication-stmts",
 717           "Maximum number of statements allowed in a block that needs to be duplicated when threading jumps.",
 718           15, 0, 0)
 719
 720 /* This is the maximum number of fields a variable may have before the pointer analysis machinery
 721    will stop trying to treat it in a field-sensitive manner.
 722    There are programs out there with thousands of fields per structure, and handling them
 723    field-sensitively is not worth the cost.  */
 724 DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
 725           "max-fields-for-field-sensitive",
 726           "Maximum number of fields in a structure before pointer analysis treats the structure as a single variable.",
 727           0, 0, 0)
 728
 729 DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
 730          "max-sched-ready-insns",
 731          "The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass.",
 732          100, 0, 0)
 733
 734 /* This is the maximum number of active local stores RTL DSE will consider.  */
 735 DEFPARAM (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES,
 736           "max-dse-active-local-stores",
 737           "Maximum number of active local stores in RTL dead store elimination.",
 738           5000, 0, 0)
 739
 740 /* Prefetching and cache-optimizations related parameters.  Default values are
 741    usually set by machine description.  */
 742
 743 /* The number of insns executed before prefetch is completed.  */
 744
 745 DEFPARAM (PARAM_PREFETCH_LATENCY,
 746          "prefetch-latency",
 747          "The number of insns executed before prefetch is completed.",
 748          200, 0, 0)
 749
 750 /* The number of prefetches that can run at the same time.  */
 751
 752 DEFPARAM (PARAM_SIMULTANEOUS_PREFETCHES,
 753           "simultaneous-prefetches",
 754           "The number of prefetches that can run at the same time.",
 755           3, 0, 0)
 756
 757 /* The size of L1 cache in kB.  */
 758
 759 DEFPARAM (PARAM_L1_CACHE_SIZE,
 760           "l1-cache-size",
 761           "The size of L1 cache.",
 762           64, 0, 0)
 763
 764 /* The size of L1 cache line in bytes.  */
 765
 766 DEFPARAM (PARAM_L1_CACHE_LINE_SIZE,
 767           "l1-cache-line-size",
 768           "The size of L1 cache line.",
 769           32, 0, 0)
 770
 771 /* The size of L2 cache in kB.  */
 772
 773 DEFPARAM (PARAM_L2_CACHE_SIZE,
 774           "l2-cache-size",
 775           "The size of L2 cache.",
 776           512, 0, 0)
 777
 778 /* Whether we should use canonical types rather than deep "structural"
 779    type checking.  Setting this value to 1 (the default) improves
 780    compilation performance in the C++ and Objective-C++ front end;
 781    this value should only be set to zero to work around bugs in the
 782    canonical type system by disabling it.  */
 783
 784 DEFPARAM (PARAM_USE_CANONICAL_TYPES,
 785           "use-canonical-types",
 786           "Whether to use canonical types.",
 787           1, 0, 1)
 788
 789 DEFPARAM (PARAM_MAX_PARTIAL_ANTIC_LENGTH,
 790           "max-partial-antic-length",
 791           "Maximum length of partial antic set when performing tree pre optimization.",
 792           100, 0, 0)
 793
 794 /* The following is used as a stop-gap limit for cases where really huge
 795    SCCs blow up memory and compile-time use too much.  If we hit this limit,
 796    SCCVN and such FRE and PRE will be not done at all for the current
 797    function.  */
 798
 799 DEFPARAM (PARAM_SCCVN_MAX_SCC_SIZE,
 800           "sccvn-max-scc-size",
 801           "Maximum size of a SCC before SCCVN stops processing a function.",
 802           10000, 10, 0)
 803
 804 /* The following is used as a stop-gap limit for cases where really huge
 805    functions blow up compile-time use too much.  It limits the number of
 806    alias-queries we do for finding common subexpressions for memory loads and
 807    stores.  The number of alias-queries is otherwise limited by the number of
 808    stores on paths to function entry.  */
 809
 810 DEFPARAM (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS,
 811           "sccvn-max-alias-queries-per-access",
 812           "Maximum number of disambiguations to perform per memory access.",
 813           1000, 0, 0)
 814
 815 DEFPARAM (PARAM_IRA_MAX_LOOPS_NUM,
 816           "ira-max-loops-num",
 817           "Max loops number for regional RA.",
 818           100, 0, 0)
 819
 820 DEFPARAM (PARAM_IRA_MAX_CONFLICT_TABLE_SIZE,
 821           "ira-max-conflict-table-size",
 822           "Max size of conflict table in MB.",
 823           1000, 0, 0)
 824
 825 DEFPARAM (PARAM_IRA_LOOP_RESERVED_REGS,
 826           "ira-loop-reserved-regs",
 827           "The number of registers in each class kept unused by loop invariant motion.",
 828           2, 0, 0)
 829
 830 DEFPARAM (PARAM_LRA_MAX_CONSIDERED_RELOAD_PSEUDOS,
 831           "lra-max-considered-reload-pseudos",
 832           "The max number of reload pseudos which are considered during spilling a non-reload pseudo.",
 833           500, 0, 0)
 834
 835 DEFPARAM (PARAM_LRA_INHERITANCE_EBB_PROBABILITY_CUTOFF,
 836           "lra-inheritance-ebb-probability-cutoff",
 837           "Minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA.",
 838           40, 0, 100)
 839
 840 /* Switch initialization conversion will refuse to create arrays that are
 841    bigger than this parameter times the number of switch branches.  */
 842
 843 DEFPARAM (PARAM_SWITCH_CONVERSION_BRANCH_RATIO,
 844           "switch-conversion-max-branch-ratio",
 845           "The maximum ratio between array size and switch branches for "
 846           "a switch conversion to take place.",
 847           8, 1, 0)
 848
 849 /* Size of tiles when doing loop blocking.  */
 850
 851 DEFPARAM (PARAM_LOOP_BLOCK_TILE_SIZE,
 852           "loop-block-tile-size",
 853           "size of tiles for loop blocking.",
 854           51, 0, 0)
 855
 856 /* Maximal number of parameters that we allow in a SCoP.  */
 857
 858 DEFPARAM (PARAM_GRAPHITE_MAX_NB_SCOP_PARAMS,
 859           "graphite-max-nb-scop-params",
 860           "maximum number of parameters in a SCoP.",
 861           7, 0, 0)
 862
 863 /* Maximal number of basic blocks in the functions analyzed by Graphite.  */
 864
 865 DEFPARAM (PARAM_GRAPHITE_MAX_BBS_PER_FUNCTION,
 866           "graphite-max-bbs-per-function",
 867           "maximum number of basic blocks per function to be analyzed by Graphite.",
 868           100, 0, 0)
 869
 870 /* Maximal number of array references in a scop.  */
 871
 872 DEFPARAM (PARAM_GRAPHITE_MAX_ARRAYS_PER_SCOP,
 873           "graphite-max-arrays-per-scop",
 874           "maximum number of arrays per scop.",
 875           100, 0, 0)
 876
 877 /* Maximal number of basic blocks in the functions analyzed by Graphite.  */
 878
 879 DEFPARAM (PARAM_GRAPHITE_MIN_LOOPS_PER_FUNCTION,
 880           "graphite-min-loops-per-function",
 881           "minimal number of loops per function to be analyzed by Graphite.",
 882           2, 0, 0)
 883
 884 DEFPARAM (PARAM_MAX_ISL_OPERATIONS,
 885           "max-isl-operations",
 886           "maximum number of isl operations, 0 means unlimited",
 887           350000, 0, 0)
 888
 889 /* Avoid data dependence analysis on very large loops.  */
 890 DEFPARAM (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS,
 891           "loop-max-datarefs-for-datadeps",
 892           "Maximum number of datarefs in loop for building loop data dependencies.",
 893           1000, 0, 0)
 894
 895 /* Avoid doing loop invariant motion on very large loops.  */
 896
 897 DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_IN_LOOP,
 898           "loop-invariant-max-bbs-in-loop",
 899           "Max basic blocks number in loop for loop invariant motion.",
 900           10000, 0, 0)
 901
 902 /* When the parameter is 1, use the internal function id
 903    to look up for profile data. Otherwise, use a more stable
 904    external id based on assembler name and source location. */
 905 DEFPARAM (PARAM_PROFILE_FUNC_INTERNAL_ID,
 906          "profile-func-internal-id",
 907          "use internal function id in profile lookup.",
 908           0, 0, 1)
 909
 910 /* When the parameter is 1, track the most frequent N target
 911    addresses in indirect-call profile. This disables
 912    indirect_call_profiler_v2 which tracks single target.  */
 913 DEFPARAM (PARAM_INDIR_CALL_TOPN_PROFILE,
 914          "indir-call-topn-profile",
 915          "track topn target addresses in indirect-call profile.",
 916           0, 0, 1)
 917
 918 /* Avoid SLP vectorization of large basic blocks.  */
 919 DEFPARAM (PARAM_SLP_MAX_INSNS_IN_BB,
 920           "slp-max-insns-in-bb",
 921           "Maximum number of instructions in basic block to be considered for SLP vectorization.",
 922           1000, 0, 0)
 923
 924 DEFPARAM (PARAM_MIN_INSN_TO_PREFETCH_RATIO,
 925           "min-insn-to-prefetch-ratio",
 926           "Min. ratio of insns to prefetches to enable prefetching for "
 927           "a loop with an unknown trip count.",
 928           9, 0, 0)
 929
 930 DEFPARAM (PARAM_PREFETCH_MIN_INSN_TO_MEM_RATIO,
 931           "prefetch-min-insn-to-mem-ratio",
 932           "Min. ratio of insns to mem ops to enable prefetching in a loop.",
 933           3, 0, 0)
 934
 935 /* Set maximum hash table size for var tracking.  */
 936
 937 DEFPARAM (PARAM_MAX_VARTRACK_SIZE,
 938           "max-vartrack-size",
 939           "Max. size of var tracking hash tables.",
 940           50000000, 0, 0)
 941
 942 /* Set maximum recursion depth for var tracking expression expansion
 943    and resolution.  */
 944
 945 DEFPARAM (PARAM_MAX_VARTRACK_EXPR_DEPTH,
 946           "max-vartrack-expr-depth",
 947           "Max. recursion depth for expanding var tracking expressions.",
 948           12, 0, 0)
 949
 950 /* Set maximum length of value location list for which var tracking
 951    should add reverse operations.  */
 952
 953 DEFPARAM (PARAM_MAX_VARTRACK_REVERSE_OP_SIZE,
 954           "max-vartrack-reverse-op-size",
 955           "Max. size of loc list for which reverse ops should be added.",
 956           50, 0, 0)
 957
 958 /* Set minimum insn uid for non-debug insns.  */
 959
 960 DEFPARAM (PARAM_MIN_NONDEBUG_INSN_UID,
 961           "min-nondebug-insn-uid",
 962           "The minimum UID to be used for a nondebug insn.",
 963           0, 1, 0)
 964
 965 DEFPARAM (PARAM_IPA_SRA_PTR_GROWTH_FACTOR,
 966           "ipa-sra-ptr-growth-factor",
 967           "Maximum allowed growth of size of new parameters ipa-sra replaces "
 968           "a pointer to an aggregate with.",
 969           2, 0, 0)
 970
 971 DEFPARAM (PARAM_TM_MAX_AGGREGATE_SIZE,
 972           "tm-max-aggregate-size",
 973           "Size in bytes after which thread-local aggregates should be "
 974           "instrumented with the logging functions instead of save/restore "
 975           "pairs.",
 976           9, 0, 0)
 977
 978 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SPEED,
 979           "sra-max-scalarization-size-Ospeed",
 980           "Maximum size, in storage units, of an aggregate which should be "
 981           "considered for scalarization when compiling for speed.",
 982           0, 0, 0)
 983
 984 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SIZE,
 985           "sra-max-scalarization-size-Osize",
 986           "Maximum size, in storage units, of an aggregate which should be "
 987           "considered for scalarization when compiling for size.",
 988           0, 0, 0)
 989
 990 DEFPARAM (PARAM_IPA_CP_VALUE_LIST_SIZE,
 991           "ipa-cp-value-list-size",
 992           "Maximum size of a list of values associated with each parameter for "
 993           "interprocedural constant propagation.",
 994           8, 0, 0)
 995
 996 DEFPARAM (PARAM_IPA_CP_EVAL_THRESHOLD,
 997           "ipa-cp-eval-threshold",
 998           "Threshold ipa-cp opportunity evaluation that is still considered "
 999           "beneficial to clone..",
1000           500, 0, 0)
1001
1002 DEFPARAM (PARAM_IPA_CP_RECURSION_PENALTY,
1003           "ipa-cp-recursion-penalty",
1004           "Percentage penalty the recursive functions will receive when they "
1005           "are evaluated for cloning..",
1006           40, 0, 100)
1007
1008 DEFPARAM (PARAM_IPA_CP_SINGLE_CALL_PENALTY,
1009           "ipa-cp-single-call-penalty",
1010           "Percentage penalty functions containg a single call to another "
1011           "function will receive when they are evaluated for cloning..",
1012           15, 0, 100)
1013
1014 DEFPARAM (PARAM_IPA_MAX_AGG_ITEMS,
1015           "ipa-max-agg-items",
1016           "Maximum number of aggregate content items for a parameter in "
1017           "jump functions and lattices.",
1018           16, 0, 0)
1019
1020 DEFPARAM (PARAM_IPA_CP_LOOP_HINT_BONUS,
1021           "ipa-cp-loop-hint-bonus",
1022           "Compile-time bonus IPA-CP assigns to candidates which make loop "
1023           "bounds or strides known..",
1024           64, 0, 0)
1025
1026 DEFPARAM (PARAM_IPA_CP_ARRAY_INDEX_HINT_BONUS,
1027           "ipa-cp-array-index-hint-bonus",
1028           "Compile-time bonus IPA-CP assigns to candidates which make an array "
1029           "index known..",
1030           48, 0, 0)
1031
1032 DEFPARAM (PARAM_IPA_MAX_AA_STEPS,
1033           "ipa-max-aa-steps",
1034           "Maximum number of statements that will be visited by IPA formal "
1035           "parameter analysis based on alias analysis in any given function.",
1036           25000, 0, 0)
1037
1038 /* WHOPR partitioning configuration.  */
1039
1040 DEFPARAM (PARAM_LTO_PARTITIONS,
1041           "lto-partitions",
1042           "Number of partitions the program should be split to.",
1043           32, 1, 0)
1044
1045 DEFPARAM (MIN_PARTITION_SIZE,
1046           "lto-min-partition",
1047           "Minimal size of a partition for LTO (in estimated instructions).",
1048           10000, 0, 0)
1049
1050 DEFPARAM (MAX_PARTITION_SIZE,
1051           "lto-max-partition",
1052           "Maximal size of a partition for LTO (in estimated instructions).",
1053           1000000, 0, INT_MAX)
1054
1055 /* Diagnostic parameters.  */
1056
1057 DEFPARAM (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP,
1058           "cxx-max-namespaces-for-diagnostic-help",
1059           "Maximum number of namespaces to search for alternatives when "
1060           "name lookup fails.",
1061           1000, 0, 0)
1062
1063 /* Maximum number of conditional store pairs that can be sunk.  */
1064 DEFPARAM (PARAM_MAX_STORES_TO_SINK,
1065           "max-stores-to-sink",
1066           "Maximum number of conditional store pairs that can be sunk.",
1067           2, 0, 0)
1068
1069 /* Override CASE_VALUES_THRESHOLD of when to switch from doing switch
1070    statements via if statements to using a table jump operation.  If the value
1071    is 0, the default CASE_VALUES_THRESHOLD will be used.  */
1072 DEFPARAM (PARAM_CASE_VALUES_THRESHOLD,
1073           "case-values-threshold",
1074           "The smallest number of different values for which it is best to "
1075           "use a jump-table instead of a tree of conditional branches, "
1076           "if 0, use the default for the machine.",
1077           0, 0, 0)
1078
1079 /* Data race flags for C++0x memory model compliance.  */
1080 DEFPARAM (PARAM_ALLOW_STORE_DATA_RACES,
1081           "allow-store-data-races",
1082           "Allow new data races on stores to be introduced.",
1083           0, 0, 1)
1084
1085 /* Reassociation width to be used by tree reassoc optimization.  */
1086 DEFPARAM (PARAM_TREE_REASSOC_WIDTH,
1087           "tree-reassoc-width",
1088           "Set the maximum number of instructions executed in parallel in "
1089           "reassociated tree. If 0, use the target dependent heuristic..",
1090           0, 0, 0)
1091
1092 DEFPARAM (PARAM_MAX_TAIL_MERGE_COMPARISONS,
1093           "max-tail-merge-comparisons",
1094           "Maximum amount of similar bbs to compare a bb with.",
1095           10, 0, 0)
1096
1097 DEFPARAM (PARAM_STORE_MERGING_ALLOW_UNALIGNED,
1098           "store-merging-allow-unaligned",
1099           "Allow the store merging pass to introduce unaligned stores "
1100           "if it is legal to do so",
1101           1, 0, 1)
1102
1103 DEFPARAM (PARAM_MAX_STORES_TO_MERGE,
1104           "max-stores-to-merge",
1105           "Maximum number of constant stores to merge in the"
1106           "store merging pass",
1107           64, 2, 0)
1108
1109 DEFPARAM (PARAM_MAX_TAIL_MERGE_ITERATIONS,
1110           "max-tail-merge-iterations",
1111           "Maximum amount of iterations of the pass over a function.",
1112           2, 0, 0)
1113
1114 /* Maximum number of strings for which strlen optimization pass will
1115    track string lenths.  */
1116 DEFPARAM (PARAM_MAX_TRACKED_STRLENS,
1117           "max-tracked-strlens",
1118           "Maximum number of strings for which strlen optimization pass will "
1119           "track string lengths.",
1120           10000, 0, 0)
1121
1122 /* Keep this in sync with the sched_pressure_algorithm enum.  */
1123 DEFPARAM (PARAM_SCHED_PRESSURE_ALGORITHM,
1124           "sched-pressure-algorithm",
1125           "Which -fsched-pressure algorithm to apply.",
1126           1, 1, 2)
1127
1128 /* Maximum length of candidate scans in straight-line strength reduction.  */
1129 DEFPARAM (PARAM_MAX_SLSR_CANDIDATE_SCAN,
1130           "max-slsr-cand-scan",
1131           "Maximum length of candidate scans for straight-line "
1132           "strength reduction.",
1133           50, 1, 999999)
1134
1135 DEFPARAM (PARAM_ASAN_STACK,
1136          "asan-stack",
1137          "Enable asan stack protection.",
1138          1, 0, 1)
1139
1140 DEFPARAM (PARAM_ASAN_GLOBALS,
1141          "asan-globals",
1142          "Enable asan globals protection.",
1143          1, 0, 1)
1144
1145 DEFPARAM (PARAM_ASAN_INSTRUMENT_WRITES,
1146          "asan-instrument-writes",
1147          "Enable asan store operations protection.",
1148          1, 0, 1)
1149
1150 DEFPARAM (PARAM_ASAN_INSTRUMENT_READS,
1151          "asan-instrument-reads",
1152          "Enable asan load operations protection.",
1153          1, 0, 1)
1154
1155 DEFPARAM (PARAM_ASAN_MEMINTRIN,
1156          "asan-memintrin",
1157          "Enable asan builtin functions protection.",
1158          1, 0, 1)
1159
1160 DEFPARAM (PARAM_ASAN_USE_AFTER_RETURN,
1161          "asan-use-after-return",
1162          "Enable asan detection of use-after-return bugs.",
1163          1, 0, 1)
1164
1165 DEFPARAM (PARAM_ASAN_INSTRUMENTATION_WITH_CALL_THRESHOLD,
1166          "asan-instrumentation-with-call-threshold",
1167          "Use callbacks instead of inline code if number of accesses "
1168          "in function becomes greater or equal to this number.",
1169          7000, 0, INT_MAX)
1170
1171 DEFPARAM (PARAM_USE_AFTER_SCOPE_DIRECT_EMISSION_THRESHOLD,
1172          "use-after-scope-direct-emission-threshold",
1173          "Use direct poisoning/unpoisoning intructions for variables "
1174          "smaller or equal to this number.",
1175          256, 0, INT_MAX)
1176
1177 DEFPARAM (PARAM_UNINIT_CONTROL_DEP_ATTEMPTS,
1178           "uninit-control-dep-attempts",
1179           "Maximum number of nested calls to search for control dependencies "
1180           "during uninitialized variable analysis.",
1181           1000, 1, 0)
1182
1183 DEFPARAM (PARAM_CHKP_MAX_CTOR_SIZE,
1184           "chkp-max-ctor-size",
1185           "Maximum number of statements to be included into a single static "
1186           "constructor generated by Pointer Bounds Checker.",
1187           5000, 100, 0)
1188
1189 DEFPARAM (PARAM_FSM_SCALE_PATH_STMTS,
1190           "fsm-scale-path-stmts",
1191           "Scale factor to apply to the number of statements in a threading path when comparing to the number of (scaled) blocks.",
1192           2, 1, 10)
1193
1194 DEFPARAM (PARAM_FSM_MAXIMUM_PHI_ARGUMENTS,
1195           "fsm-maximum-phi-arguments",
1196           "Maximum number of arguments a PHI may have before the FSM threader will not try to thread through its block.",
1197           100, 1, 999999)
1198
1199 DEFPARAM (PARAM_FSM_SCALE_PATH_BLOCKS,
1200           "fsm-scale-path-blocks",
1201           "Scale factor to apply to the number of blocks in a threading path when comparing to the number of (scaled) statements.",
1202           3, 1, 10)
1203
1204 DEFPARAM (PARAM_MAX_FSM_THREAD_PATH_INSNS,
1205           "max-fsm-thread-path-insns",
1206           "Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path.",
1207           100, 1, 999999)
1208
1209 DEFPARAM (PARAM_MAX_FSM_THREAD_LENGTH,
1210           "max-fsm-thread-length",
1211           "Maximum number of basic blocks on a finite state automaton jump thread path.",
1212           10, 1, 999999)
1213
1214 DEFPARAM (PARAM_MAX_FSM_THREAD_PATHS,
1215           "max-fsm-thread-paths",
1216           "Maximum number of new jump thread paths to create for a finite state automaton.",
1217           50, 1, 999999)
1218
1219 DEFPARAM (PARAM_PARLOOPS_CHUNK_SIZE,
1220           "parloops-chunk-size",
1221           "Chunk size of omp schedule for loops parallelized by parloops.",
1222           0, 0, 0)
1223
1224 DEFPARAMENUM5 (PARAM_PARLOOPS_SCHEDULE,
1225                "parloops-schedule",
1226                "Schedule type of omp schedule for loops parallelized by "
1227                "parloops (static, dynamic, guided, auto, runtime).",
1228                static,
1229                static, dynamic, guided, auto, runtime)
1230
1231 DEFPARAM (PARAM_MAX_SSA_NAME_QUERY_DEPTH,
1232           "max-ssa-name-query-depth",
1233           "Maximum recursion depth allowed when querying a property of an"
1234           " SSA name.",
1235           3, 1, 0)
1236
1237 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_INSNS,
1238           "max-rtl-if-conversion-insns",
1239           "Maximum number of insns in a basic block to consider for RTL "
1240           "if-conversion.",
1241           10, 0, 99)
1242
1243 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_PREDICTABLE_COST,
1244           "max-rtl-if-conversion-predictable-cost",
1245           "Maximum permissible cost for the sequence that would be "
1246           "generated by the RTL if-conversion pass for a branch that "
1247           "is considered predictable.",
1248           20, 0, 200)
1249
1250 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_UNPREDICTABLE_COST,
1251           "max-rtl-if-conversion-unpredictable-cost",
1252           "Maximum permissible cost for the sequence that would be "
1253           "generated by the RTL if-conversion pass for a branch that "
1254           "is considered unpredictable.",
1255           40, 0, 200)
1256
1257 DEFPARAM (PARAM_HSA_GEN_DEBUG_STORES,
1258           "hsa-gen-debug-stores",
1259           "Level of hsa debug stores verbosity",
1260           0, 0, 1)
1261
1262 DEFPARAM (PARAM_MAX_SPECULATIVE_DEVIRT_MAYDEFS,
1263           "max-speculative-devirt-maydefs",
1264           "Maximum number of may-defs visited when devirtualizing "
1265           "speculatively", 50, 0, 0)
1266
1267 DEFPARAM (PARAM_MAX_VRP_SWITCH_ASSERTIONS,
1268           "max-vrp-switch-assertions",
1269           "Maximum number of assertions to add along the default "
1270           "edge of a switch statement during VRP",
1271           10, 0, 0)
1272
1273 DEFPARAM (PARAM_VECT_EPILOGUES_NOMASK,
1274           "vect-epilogues-nomask",
1275           "Enable loop epilogue vectorization using smaller vector size.",
1276           0, 0, 1)
1277
1278 /*
1279
1280 Local variables:
1281 mode:c
1282 End:
1283 */