gcc/params.def

   1 /* params.def - Run-time parameters.
   2    Copyright (C) 2001-2018 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-insns-auto.",
  55           15, 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 400.
  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 30.  */
  81 DEFPARAM (PARAM_MAX_INLINE_INSNS_AUTO,
  82           "max-inline-insns-auto",
  83           "The maximum number of instructions when automatically inlining.",
  84           30, 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, 100)
 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           0, 0, 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 DEFPARAM(PARAM_STACK_CLASH_PROTECTION_GUARD_SIZE,
 217          "stack-clash-protection-guard-size",
 218          "Size of the stack guard expressed as a power of two.",
 219          12, 12, 30)
 220
 221 DEFPARAM(PARAM_STACK_CLASH_PROTECTION_PROBE_INTERVAL,
 222          "stack-clash-protection-probe-interval",
 223          "Interval in which to probe the stack expressed as a power of two.",
 224          12, 10, 16)
 225
 226 /* The GCSE optimization will be disabled if it would require
 227    significantly more memory than this value.  */
 228 DEFPARAM(PARAM_MAX_GCSE_MEMORY,
 229          "max-gcse-memory",
 230          "The maximum amount of memory to be allocated by GCSE.",
 231          128 * 1024 * 1024, 0, 0)
 232
 233 /* The GCSE optimization of an expression will avoided if the ratio of
 234    insertions to deletions is greater than this value.  */
 235 DEFPARAM(PARAM_MAX_GCSE_INSERTION_RATIO,
 236          "max-gcse-insertion-ratio",
 237          "The maximum ratio of insertions to deletions of expressions in GCSE.",
 238          20, 0, 0)
 239
 240 /* This is the threshold ratio when to perform partial redundancy
 241    elimination after reload. We perform partial redundancy elimination
 242    when the following holds:
 243    (Redundant load execution count)
 244    ------------------------------- >= GCSE_AFTER_RELOAD_PARTIAL_FRACTION
 245    (Added loads execution count)                                          */
 246 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_PARTIAL_FRACTION,
 247         "gcse-after-reload-partial-fraction",
 248         "The threshold ratio for performing partial redundancy elimination after reload.",
 249         3, 0, 0)
 250 /* This is the threshold ratio of the critical edges execution count compared to
 251    the redundant loads execution count that permits performing the load
 252    redundancy elimination in gcse after reload.  */
 253 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_CRITICAL_FRACTION,
 254         "gcse-after-reload-critical-fraction",
 255         "The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload.",
 256         10, 0, 0)
 257
 258 /* GCSE will use GCSE_COST_DISTANCE_RATION as a scaling factor
 259    to calculate maximum distance for which an expression is allowed to move
 260    from its rtx_cost.  */
 261 DEFPARAM(PARAM_GCSE_COST_DISTANCE_RATIO,
 262          "gcse-cost-distance-ratio",
 263          "Scaling factor in calculation of maximum distance an expression can be moved by GCSE optimizations.",
 264          10, 0, 0)
 265 /* GCSE won't restrict distance for which an expression with rtx_cost greater
 266    than COSTS_N_INSN(GCSE_UNRESTRICTED_COST) is allowed to move.  */
 267 DEFPARAM(PARAM_GCSE_UNRESTRICTED_COST,
 268          "gcse-unrestricted-cost",
 269          "Cost at which GCSE optimizations will not constraint the distance an expression can travel.",
 270          3, 0, 0)
 271
 272 /* How deep from a given basic block the dominator tree should be searched
 273    for expressions to hoist to the block.  The value of 0 will avoid limiting
 274    the search.  */
 275 DEFPARAM(PARAM_MAX_HOIST_DEPTH,
 276          "max-hoist-depth",
 277          "Maximum depth of search in the dominator tree for expressions to hoist.",
 278          30, 0, 0)
 279
 280
 281 /* When synthesizing expnonentiation by a real constant operations using square
 282    roots, this controls how deep sqrt chains we are willing to generate.  */
 283 DEFPARAM(PARAM_MAX_POW_SQRT_DEPTH,
 284          "max-pow-sqrt-depth",
 285          "Maximum depth of sqrt chains to use when synthesizing exponentiation by a real constant.",
 286          5, 1, 32)
 287
 288 /* This parameter limits the number of insns in a loop that will be unrolled,
 289    and by how much the loop is unrolled.
 290
 291    This limit should be at most half of the peeling limits:  loop unroller
 292    decides to not unroll loops that iterate fewer than 2*number of allowed
 293    unrollings and thus we would have loops that are neither peeled or unrolled
 294    otherwise.  */
 295 DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
 296          "max-unrolled-insns",
 297          "The maximum number of instructions to consider to unroll in a loop.",
 298          200, 0, 0)
 299 /* This parameter limits how many times the loop is unrolled depending
 300    on number of insns really executed in each iteration.  */
 301 DEFPARAM(PARAM_MAX_AVERAGE_UNROLLED_INSNS,
 302          "max-average-unrolled-insns",
 303          "The maximum number of instructions to consider to unroll in a loop on average.",
 304          80, 0, 0)
 305 /* The maximum number of unrollings of a single loop.  */
 306 DEFPARAM(PARAM_MAX_UNROLL_TIMES,
 307         "max-unroll-times",
 308         "The maximum number of unrollings of a single loop.",
 309         8, 0, 0)
 310 /* The maximum number of insns of a peeled loop.  */
 311 DEFPARAM(PARAM_MAX_PEELED_INSNS,
 312         "max-peeled-insns",
 313         "The maximum number of insns of a peeled loop.",
 314         100, 0, 0)
 315 /* The maximum number of peelings of a single loop.  */
 316 DEFPARAM(PARAM_MAX_PEEL_TIMES,
 317         "max-peel-times",
 318         "The maximum number of peelings of a single loop.",
 319         16, 0, 0)
 320 /* The maximum number of peelings of a single loop that is peeled completely.  */
 321 DEFPARAM(PARAM_MAX_PEEL_BRANCHES,
 322         "max-peel-branches",
 323         "The maximum number of branches on the path through the peeled sequence.",
 324         32, 0, 0)
 325 /* The maximum number of insns of a peeled loop.  */
 326 DEFPARAM(PARAM_MAX_COMPLETELY_PEELED_INSNS,
 327         "max-completely-peeled-insns",
 328         "The maximum number of insns of a completely peeled loop.",
 329         200, 0, 0)
 330 /* The maximum number of peelings of a single loop that is peeled completely.  */
 331 DEFPARAM(PARAM_MAX_COMPLETELY_PEEL_TIMES,
 332         "max-completely-peel-times",
 333         "The maximum number of peelings of a single loop that is peeled completely.",
 334         16, 0, 0)
 335 /* The maximum number of insns of a peeled loop that rolls only once.  */
 336 DEFPARAM(PARAM_MAX_ONCE_PEELED_INSNS,
 337         "max-once-peeled-insns",
 338         "The maximum number of insns of a peeled loop that rolls only once.",
 339         400, 0, 0)
 340 /* The maximum depth of a loop nest we completely peel.  */
 341 DEFPARAM(PARAM_MAX_UNROLL_ITERATIONS,
 342          "max-completely-peel-loop-nest-depth",
 343          "The maximum depth of a loop nest we completely peel.",
 344          8, 0, 0)
 345
 346 /* The maximum number of insns of an unswitched loop.  */
 347 DEFPARAM(PARAM_MAX_UNSWITCH_INSNS,
 348         "max-unswitch-insns",
 349         "The maximum number of insns of an unswitched loop.",
 350         50, 0, 0)
 351 /* The maximum level of recursion in unswitch_single_loop.  */
 352 DEFPARAM(PARAM_MAX_UNSWITCH_LEVEL,
 353         "max-unswitch-level",
 354         "The maximum number of unswitchings in a single loop.",
 355         3, 0, 0)
 356
 357 /* The maximum number of insns in loop header duplicated by the copy loop
 358    headers pass.  */
 359 DEFPARAM(PARAM_MAX_LOOP_HEADER_INSNS,
 360         "max-loop-header-insns",
 361         "The maximum number of insns in loop header duplicated by the copy loop headers pass.",
 362         20, 0, 0)
 363
 364 /* The maximum number of iterations of a loop the brute force algorithm
 365    for analysis of # of iterations of the loop tries to evaluate.  */
 366 DEFPARAM(PARAM_MAX_ITERATIONS_TO_TRACK,
 367         "max-iterations-to-track",
 368         "Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates.",
 369         1000, 0, 0)
 370 /* A cutoff to avoid costly computations of the number of iterations in
 371    the doloop transformation.  */
 372 DEFPARAM(PARAM_MAX_ITERATIONS_COMPUTATION_COST,
 373         "max-iterations-computation-cost",
 374         "Bound on the cost of an expression to compute the number of iterations.",
 375         10, 0, 0)
 376
 377 /* This parameter is used to tune SMS MAX II calculations.  */
 378 DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
 379          "sms-max-ii-factor",
 380          "A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop.",
 381          100, 0, 0)
 382 /* The minimum value of stage count that swing modulo scheduler will generate.  */
 383 DEFPARAM(PARAM_SMS_MIN_SC,
 384         "sms-min-sc",
 385         "The minimum value of stage count that swing modulo scheduler will generate.",
 386         2, 1, 1)
 387 DEFPARAM(PARAM_SMS_DFA_HISTORY,
 388          "sms-dfa-history",
 389          "The number of cycles the swing modulo scheduler considers when checking conflicts using DFA.",
 390          0, 0, 0)
 391 DEFPARAM(PARAM_SMS_LOOP_AVERAGE_COUNT_THRESHOLD,
 392          "sms-loop-average-count-threshold",
 393          "A threshold on the average loop count considered by the swing modulo scheduler.",
 394          0, 0, 0)
 395
 396 DEFPARAM(HOT_BB_COUNT_WS_PERMILLE,
 397          "hot-bb-count-ws-permille",
 398          "A basic block profile count is considered hot if it contributes to "
 399          "the given permillage of the entire profiled execution.",
 400          999, 0, 1000)
 401 DEFPARAM(HOT_BB_FREQUENCY_FRACTION,
 402          "hot-bb-frequency-fraction",
 403          "Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot.",
 404          1000, 0, 0)
 405
 406 DEFPARAM(UNLIKELY_BB_COUNT_FRACTION,
 407          "unlikely-bb-count-fraction",
 408          "The minimum fraction of profile runs a given basic block execution count must be not to be considered unlikely.",
 409          20, 1, 10000)
 410
 411 DEFPARAM (PARAM_ALIGN_THRESHOLD,
 412           "align-threshold",
 413           "Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment.",
 414           100, 1, 0)
 415
 416 DEFPARAM (PARAM_ALIGN_LOOP_ITERATIONS,
 417           "align-loop-iterations",
 418           "Loops iterating at least selected number of iterations will get loop alignment..",
 419           4, 0, 0)
 420
 421 /* For guessed profiles, the loops having unknown number of iterations
 422    are predicted to iterate relatively few (10) times at average.
 423    For functions containing one loop with large known number of iterations
 424    and other loops having unbounded loops we would end up predicting all
 425    the other loops cold that is not usually the case.  So we need to artificially
 426    flatten the profile.
 427
 428    We need to cut the maximal predicted iterations to large enough iterations
 429    so the loop appears important, but safely within maximum hotness
 430    range.  */
 431
 432 DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
 433          "max-predicted-iterations",
 434          "The maximum number of loop iterations we predict statically.",
 435          100, 0, 0)
 436
 437 /* This parameter controls the probability of builtin_expect. The default
 438    value is 90%. This empirical value is obtained through the weighted
 439    probability of FDO counters (with the FDO count value as the weight)
 440    in some real world programs:
 441    (1) Google performance test benchmarks: the probability is 0.9081.
 442    (2) Linux 3.3 kernel running Google search workload: the probability
 443    is 0.8717.  */
 444
 445 DEFPARAM(BUILTIN_EXPECT_PROBABILITY,
 446          "builtin-expect-probability",
 447          "Set the estimated probability in percentage for builtin expect. The default value is 90% probability.",
 448          90, 0, 100)
 449 DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK,
 450          "tracer-dynamic-coverage-feedback",
 451          "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available.",
 452          95, 0, 100)
 453 DEFPARAM(TRACER_DYNAMIC_COVERAGE,
 454          "tracer-dynamic-coverage",
 455          "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available.",
 456          75, 0, 100)
 457 DEFPARAM(TRACER_MAX_CODE_GROWTH,
 458          "tracer-max-code-growth",
 459          "Maximal code growth caused by tail duplication (in percent).",
 460          100, 0, 0)
 461 DEFPARAM(TRACER_MIN_BRANCH_RATIO,
 462          "tracer-min-branch-ratio",
 463          "Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent).",
 464          10, 0, 100)
 465 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK,
 466          "tracer-min-branch-probability-feedback",
 467          "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available.",
 468          80, 0, 100)
 469 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY,
 470          "tracer-min-branch-probability",
 471          "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available.",
 472          50, 0, 100)
 473
 474 /* The maximum number of incoming edges to consider for crossjumping.  */
 475 DEFPARAM(PARAM_MAX_CROSSJUMP_EDGES,
 476          "max-crossjump-edges",
 477          "The maximum number of incoming edges to consider for crossjumping.",
 478          100, 0, 0)
 479
 480 /* The minimum number of matching instructions to consider for crossjumping.  */
 481 DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
 482      "min-crossjump-insns",
 483      "The minimum number of matching instructions to consider for crossjumping.",
 484      5, 1, 0)
 485
 486 /* The maximum number expansion factor when copying basic blocks.  */
 487 DEFPARAM(PARAM_MAX_GROW_COPY_BB_INSNS,
 488      "max-grow-copy-bb-insns",
 489      "The maximum expansion factor when copying basic blocks.",
 490      8, 0, 0)
 491
 492 /* The maximum number of insns to duplicate when unfactoring computed gotos.  */
 493 DEFPARAM(PARAM_MAX_GOTO_DUPLICATION_INSNS,
 494      "max-goto-duplication-insns",
 495      "The maximum number of insns to duplicate when unfactoring computed gotos.",
 496      8, 0, 0)
 497
 498 /* The maximum length of path considered in cse.  */
 499 DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
 500          "max-cse-path-length",
 501          "The maximum length of path considered in cse.",
 502          10, 1, 0)
 503 DEFPARAM(PARAM_MAX_CSE_INSNS,
 504          "max-cse-insns",
 505          "The maximum instructions CSE process before flushing.",
 506          1000, 0, 0)
 507
 508 /* The cost of expression in loop invariant motion that is considered
 509    expensive.  */
 510 DEFPARAM(PARAM_LIM_EXPENSIVE,
 511          "lim-expensive",
 512          "The minimum cost of an expensive expression in the loop invariant motion.",
 513          20, 0, 0)
 514
 515 /* Bound on number of candidates for induction variables below that
 516    all candidates are considered for each use in induction variable
 517    optimizations.  */
 518
 519 DEFPARAM(PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND,
 520          "iv-consider-all-candidates-bound",
 521          "Bound on number of candidates below that all candidates are considered in iv optimizations.",
 522          40, 0, 0)
 523
 524 /* The induction variable optimizations give up on loops that contain more
 525    induction variable uses.  */
 526
 527 DEFPARAM(PARAM_IV_MAX_CONSIDERED_USES,
 528          "iv-max-considered-uses",
 529          "Bound on number of iv uses in loop optimized in iv optimizations.",
 530          250, 0, 0)
 531
 532 /* If there are at most this number of ivs in the set, try removing unnecessary
 533    ivs from the set always.  */
 534
 535 DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
 536          "iv-always-prune-cand-set-bound",
 537          "If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization.",
 538          10, 0, 0)
 539
 540 DEFPARAM(PARAM_AVG_LOOP_NITER,
 541          "avg-loop-niter",
 542          "Average number of iterations of a loop.",
 543          10, 1, 0)
 544
 545 DEFPARAM(PARAM_DSE_MAX_OBJECT_SIZE,
 546          "dse-max-object-size",
 547          "Maximum size (in bytes) of objects tracked bytewise by dead store elimination.",
 548          256, 0, 0)
 549
 550 DEFPARAM(PARAM_DSE_MAX_ALIAS_QUERIES_PER_STORE,
 551          "dse-max-alias-queries-per-store",
 552          "Maximum number of queries into the alias oracle per store.",
 553          256, 0, 0)
 554
 555 DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
 556          "scev-max-expr-size",
 557          "Bound on size of expressions used in the scalar evolutions analyzer.",
 558          100, 0, 0)
 559
 560 DEFPARAM(PARAM_SCEV_MAX_EXPR_COMPLEXITY,
 561          "scev-max-expr-complexity",
 562          "Bound on the complexity of the expressions in the scalar evolutions analyzer.",
 563          10, 0, 0)
 564
 565 DEFPARAM (PARAM_MAX_TREE_IF_CONVERSION_PHI_ARGS,
 566           "max-tree-if-conversion-phi-args",
 567           "Maximum number of arguments in a PHI supported by TREE if-conversion "
 568           "unless the loop is marked with simd pragma.",
 569           4, 2, 0)
 570
 571 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS,
 572          "vect-max-version-for-alignment-checks",
 573          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check.",
 574          6, 0, 0)
 575
 576 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS,
 577          "vect-max-version-for-alias-checks",
 578          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check.",
 579          10, 0, 0)
 580
 581 DEFPARAM(PARAM_VECT_MAX_PEELING_FOR_ALIGNMENT,
 582          "vect-max-peeling-for-alignment",
 583          "Maximum number of loop peels to enhance alignment of data references in a loop.",
 584          -1, -1, 64)
 585
 586 DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
 587          "max-cselib-memory-locations",
 588          "The maximum memory locations recorded by cselib.",
 589          500, 0, 0)
 590
 591 #ifdef ENABLE_GC_ALWAYS_COLLECT
 592 # define GGC_MIN_EXPAND_DEFAULT 0
 593 # define GGC_MIN_HEAPSIZE_DEFAULT 0
 594 #else
 595 # define GGC_MIN_EXPAND_DEFAULT 30
 596 # define GGC_MIN_HEAPSIZE_DEFAULT 4096
 597 #endif
 598
 599 DEFPARAM(GGC_MIN_EXPAND,
 600          "ggc-min-expand",
 601          "Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap.",
 602          GGC_MIN_EXPAND_DEFAULT, 0, 0)
 603
 604 DEFPARAM(GGC_MIN_HEAPSIZE,
 605          "ggc-min-heapsize",
 606          "Minimum heap size before we start collecting garbage, in kilobytes.",
 607          GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
 608
 609 #undef GGC_MIN_EXPAND_DEFAULT
 610 #undef GGC_MIN_HEAPSIZE_DEFAULT
 611
 612 DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
 613          "max-reload-search-insns",
 614          "The maximum number of instructions to search backward when looking for equivalent reload.",
 615          100, 0, 0)
 616
 617 DEFPARAM(PARAM_SINK_FREQUENCY_THRESHOLD,
 618          "sink-frequency-threshold",
 619          "Target block's relative execution frequency (as a percentage) required to sink a statement.",
 620          75, 0, 100)
 621
 622 DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
 623          "max-sched-region-blocks",
 624          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 625          10, 0, 0)
 626
 627 DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
 628          "max-sched-region-insns",
 629          "The maximum number of insns in a region to be considered for interblock scheduling.",
 630          100, 0, 0)
 631
 632 DEFPARAM(PARAM_MAX_PIPELINE_REGION_BLOCKS,
 633          "max-pipeline-region-blocks",
 634          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 635          15, 0, 0)
 636
 637 DEFPARAM(PARAM_MAX_PIPELINE_REGION_INSNS,
 638          "max-pipeline-region-insns",
 639          "The maximum number of insns in a region to be considered for interblock scheduling.",
 640          200, 0, 0)
 641
 642 DEFPARAM(PARAM_MIN_SPEC_PROB,
 643          "min-spec-prob",
 644          "The minimum probability of reaching a source block for interblock speculative scheduling.",
 645          40, 0, 0)
 646
 647 DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
 648          "max-sched-extend-regions-iters",
 649          "The maximum number of iterations through CFG to extend regions.",
 650          0, 0, 0)
 651
 652 DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
 653          "max-sched-insn-conflict-delay",
 654          "The maximum conflict delay for an insn to be considered for speculative motion.",
 655          3, 1, 10)
 656
 657 DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
 658          "sched-spec-prob-cutoff",
 659          "The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
 660          40, 0, 100)
 661
 662 DEFPARAM(PARAM_SCHED_STATE_EDGE_PROB_CUTOFF,
 663          "sched-state-edge-prob-cutoff",
 664          "The minimum probability an edge must have for the scheduler to save its state across it.",
 665          10, 0, 100)
 666
 667 DEFPARAM(PARAM_SELSCHED_MAX_LOOKAHEAD,
 668          "selsched-max-lookahead",
 669          "The maximum size of the lookahead window of selective scheduling.",
 670          50, 0, 0)
 671
 672 DEFPARAM(PARAM_SELSCHED_MAX_SCHED_TIMES,
 673          "selsched-max-sched-times",
 674          "Maximum number of times that an insn could be scheduled.",
 675          2, 1, 0)
 676
 677 DEFPARAM(PARAM_SELSCHED_INSNS_TO_RENAME,
 678          "selsched-insns-to-rename",
 679          "Maximum number of instructions in the ready list that are considered eligible for renaming.",
 680          2, 0, 0)
 681
 682 DEFPARAM (PARAM_SCHED_MEM_TRUE_DEP_COST,
 683           "sched-mem-true-dep-cost",
 684           "Minimal distance between possibly conflicting store and load.",
 685           1, 0, 0)
 686
 687 DEFPARAM (PARAM_SCHED_AUTOPREF_QUEUE_DEPTH,
 688           "sched-autopref-queue-depth",
 689           "Hardware autoprefetcher scheduler model control flag.  Number of lookahead cycles the model looks into; at '0' only enable instruction sorting heuristic.  Disabled by default.",
 690           -1, 0, 0)
 691
 692 DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
 693          "max-last-value-rtl",
 694          "The maximum number of RTL nodes that can be recorded as combiner's last value.",
 695          10000, 0, 0)
 696
 697 DEFPARAM(PARAM_MAX_COMBINE_INSNS,
 698          "max-combine-insns",
 699          "The maximum number of insns combine tries to combine.",
 700          4, 2, 4)
 701
 702 /* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
 703    {signed,unsigned} integral types.  This determines N.
 704    Experimentation shows 251 to be a good value that generates the
 705    least amount of garbage for allocating the TREE_VEC storage.  */
 706 DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
 707           "integer-share-limit",
 708           "The upper bound for sharing integer constants.",
 709           251, 2, 2)
 710
 711 DEFPARAM (PARAM_SSP_BUFFER_SIZE,
 712           "ssp-buffer-size",
 713           "The lower bound for a buffer to be considered for stack smashing protection.",
 714           8, 1, 0)
 715
 716 DEFPARAM (PARAM_MIN_SIZE_FOR_STACK_SHARING,
 717           "min-size-for-stack-sharing",
 718           "The minimum size of variables taking part in stack slot sharing "
 719           "when not optimizing.",
 720           32, 0, 0)
 721
 722 /* When we thread through a block we have to make copies of the
 723    statements within the block.  Clearly for large blocks the code
 724    duplication is bad.
 725
 726    PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
 727    of statements and PHI nodes allowed in a block which is going to
 728    be duplicated for thread jumping purposes.
 729
 730    Some simple analysis showed that more than 99% of the jump
 731    threading opportunities are for blocks with less than 15
 732    statements.  So we can get the benefits of jump threading
 733    without excessive code bloat for pathological cases with the
 734    throttle set at 15 statements.  */
 735 DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
 736           "max-jump-thread-duplication-stmts",
 737           "Maximum number of statements allowed in a block that needs to be duplicated when threading jumps.",
 738           15, 0, 0)
 739
 740 /* This is the maximum number of fields a variable may have before the pointer analysis machinery
 741    will stop trying to treat it in a field-sensitive manner.
 742    There are programs out there with thousands of fields per structure, and handling them
 743    field-sensitively is not worth the cost.  */
 744 DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
 745           "max-fields-for-field-sensitive",
 746           "Maximum number of fields in a structure before pointer analysis treats the structure as a single variable.",
 747           0, 0, 0)
 748
 749 DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
 750          "max-sched-ready-insns",
 751          "The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass.",
 752          100, 1, 0)
 753
 754 /* This is the maximum number of active local stores RTL DSE will consider.  */
 755 DEFPARAM (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES,
 756           "max-dse-active-local-stores",
 757           "Maximum number of active local stores in RTL dead store elimination.",
 758           5000, 0, 0)
 759
 760 /* Prefetching and cache-optimizations related parameters.  Default values are
 761    usually set by machine description.  */
 762
 763 /* The number of insns executed before prefetch is completed.  */
 764
 765 DEFPARAM (PARAM_PREFETCH_LATENCY,
 766          "prefetch-latency",
 767          "The number of insns executed before prefetch is completed.",
 768          200, 0, 0)
 769
 770 /* The number of prefetches that can run at the same time.  */
 771
 772 DEFPARAM (PARAM_SIMULTANEOUS_PREFETCHES,
 773           "simultaneous-prefetches",
 774           "The number of prefetches that can run at the same time.",
 775           3, 0, 0)
 776
 777 /* The size of L1 cache in kB.  */
 778
 779 DEFPARAM (PARAM_L1_CACHE_SIZE,
 780           "l1-cache-size",
 781           "The size of L1 cache.",
 782           64, 0, 0)
 783
 784 /* The size of L1 cache line in bytes.  */
 785
 786 DEFPARAM (PARAM_L1_CACHE_LINE_SIZE,
 787           "l1-cache-line-size",
 788           "The size of L1 cache line.",
 789           32, 0, 0)
 790
 791 /* The size of L2 cache in kB.  */
 792
 793 DEFPARAM (PARAM_L2_CACHE_SIZE,
 794           "l2-cache-size",
 795           "The size of L2 cache.",
 796           512, 0, 0)
 797
 798 /* Whether software prefetch hints should be issued for non-constant
 799    strides.  */
 800
 801 DEFPARAM (PARAM_PREFETCH_DYNAMIC_STRIDES,
 802           "prefetch-dynamic-strides",
 803           "Whether software prefetch hints should be issued for non-constant "
 804           "strides.",
 805           1, 0, 1)
 806
 807 /* The minimum constant stride beyond which we should use prefetch hints
 808    for.  */
 809
 810 DEFPARAM (PARAM_PREFETCH_MINIMUM_STRIDE,
 811           "prefetch-minimum-stride",
 812           "The minimum constant stride beyond which we should use prefetch "
 813           "hints for.",
 814           -1, 0, 0)
 815
 816 /* Maximum number of statements in loop nest for loop interchange.  */
 817
 818 DEFPARAM (PARAM_LOOP_INTERCHANGE_MAX_NUM_STMTS,
 819           "loop-interchange-max-num-stmts",
 820           "The maximum number of stmts in loop nest for loop interchange.",
 821           64, 0, 0)
 822
 823 /* Minimum stride ratio for loop interchange to be profitiable.  */
 824
 825 DEFPARAM (PARAM_LOOP_INTERCHANGE_STRIDE_RATIO,
 826           "loop-interchange-stride-ratio",
 827           "The minimum stride ratio for loop interchange to be profitable",
 828           2, 0, 0)
 829
 830 /* Whether we should use canonical types rather than deep "structural"
 831    type checking.  Setting this value to 1 (the default) improves
 832    compilation performance in the C++ and Objective-C++ front end;
 833    this value should only be set to zero to work around bugs in the
 834    canonical type system by disabling it.  */
 835
 836 DEFPARAM (PARAM_USE_CANONICAL_TYPES,
 837           "use-canonical-types",
 838           "Whether to use canonical types.",
 839           1, 0, 1)
 840
 841 DEFPARAM (PARAM_MAX_PARTIAL_ANTIC_LENGTH,
 842           "max-partial-antic-length",
 843           "Maximum length of partial antic set when performing tree pre optimization.",
 844           100, 0, 0)
 845
 846 /* The following is used as a stop-gap limit for cases where really huge
 847    SCCs blow up memory and compile-time use too much.  If we hit this limit,
 848    SCCVN and such FRE and PRE will be not done at all for the current
 849    function.  */
 850
 851 DEFPARAM (PARAM_SCCVN_MAX_SCC_SIZE,
 852           "sccvn-max-scc-size",
 853           "Maximum size of a SCC before SCCVN stops processing a function.",
 854           10000, 10, 0)
 855
 856 /* The following is used as a stop-gap limit for cases where really huge
 857    functions blow up compile-time use too much.  It limits the number of
 858    alias-queries we do for finding common subexpressions for memory loads and
 859    stores.  The number of alias-queries is otherwise limited by the number of
 860    stores on paths to function entry.  */
 861
 862 DEFPARAM (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS,
 863           "sccvn-max-alias-queries-per-access",
 864           "Maximum number of disambiguations to perform per memory access.",
 865           1000, 0, 0)
 866
 867 DEFPARAM (PARAM_IRA_MAX_LOOPS_NUM,
 868           "ira-max-loops-num",
 869           "Max loops number for regional RA.",
 870           100, 0, 0)
 871
 872 DEFPARAM (PARAM_IRA_MAX_CONFLICT_TABLE_SIZE,
 873           "ira-max-conflict-table-size",
 874           "Max size of conflict table in MB.",
 875           1000, 0, 0)
 876
 877 DEFPARAM (PARAM_IRA_LOOP_RESERVED_REGS,
 878           "ira-loop-reserved-regs",
 879           "The number of registers in each class kept unused by loop invariant motion.",
 880           2, 0, 0)
 881
 882 DEFPARAM (PARAM_LRA_MAX_CONSIDERED_RELOAD_PSEUDOS,
 883           "lra-max-considered-reload-pseudos",
 884           "The max number of reload pseudos which are considered during spilling a non-reload pseudo.",
 885           500, 0, 0)
 886
 887 DEFPARAM (PARAM_LRA_INHERITANCE_EBB_PROBABILITY_CUTOFF,
 888           "lra-inheritance-ebb-probability-cutoff",
 889           "Minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA.",
 890           40, 0, 100)
 891
 892 /* Switch initialization conversion will refuse to create arrays that are
 893    bigger than this parameter times the number of switch branches.  */
 894
 895 DEFPARAM (PARAM_SWITCH_CONVERSION_BRANCH_RATIO,
 896           "switch-conversion-max-branch-ratio",
 897           "The maximum ratio between array size and switch branches for "
 898           "a switch conversion to take place.",
 899           8, 1, 0)
 900
 901 /* Size of tiles when doing loop blocking.  */
 902
 903 DEFPARAM (PARAM_LOOP_BLOCK_TILE_SIZE,
 904           "loop-block-tile-size",
 905           "size of tiles for loop blocking.",
 906           51, 0, 0)
 907
 908 /* Maximal number of parameters that we allow in a SCoP.  */
 909
 910 DEFPARAM (PARAM_GRAPHITE_MAX_NB_SCOP_PARAMS,
 911           "graphite-max-nb-scop-params",
 912           "maximum number of parameters in a SCoP.",
 913           10, 0, 0)
 914
 915 /* Maximal number of array references in a scop.  */
 916
 917 DEFPARAM (PARAM_GRAPHITE_MAX_ARRAYS_PER_SCOP,
 918           "graphite-max-arrays-per-scop",
 919           "maximum number of arrays per scop.",
 920           100, 0, 0)
 921
 922 DEFPARAM (PARAM_MAX_ISL_OPERATIONS,
 923           "max-isl-operations",
 924           "maximum number of isl operations, 0 means unlimited",
 925           350000, 0, 0)
 926
 927 /* For testsuite purposes allow to check for codegen error handling.  */
 928 DEFPARAM (PARAM_GRAPHITE_ALLOW_CODEGEN_ERRORS,
 929           "graphite-allow-codegen-errors",
 930           "whether codegen errors should be ICEs when -fchecking.",
 931           0, 0, 1)
 932
 933 /* Avoid data dependence analysis on very large loops.  */
 934 DEFPARAM (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS,
 935           "loop-max-datarefs-for-datadeps",
 936           "Maximum number of datarefs in loop for building loop data dependencies.",
 937           1000, 0, 0)
 938
 939 /* Avoid doing loop invariant motion on very large loops.  */
 940
 941 DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_IN_LOOP,
 942           "loop-invariant-max-bbs-in-loop",
 943           "Max basic blocks number in loop for loop invariant motion.",
 944           10000, 0, 0)
 945
 946 /* When the parameter is 1, use the internal function id
 947    to look up for profile data. Otherwise, use a more stable
 948    external id based on assembler name and source location. */
 949 DEFPARAM (PARAM_PROFILE_FUNC_INTERNAL_ID,
 950          "profile-func-internal-id",
 951          "use internal function id in profile lookup.",
 952           0, 0, 1)
 953
 954 /* When the parameter is 1, track the most frequent N target
 955    addresses in indirect-call profile. This disables
 956    indirect_call_profiler_v2 which tracks single target.  */
 957 DEFPARAM (PARAM_INDIR_CALL_TOPN_PROFILE,
 958          "indir-call-topn-profile",
 959          "track topn target addresses in indirect-call profile.",
 960           0, 0, 1)
 961
 962 /* Avoid SLP vectorization of large basic blocks.  */
 963 DEFPARAM (PARAM_SLP_MAX_INSNS_IN_BB,
 964           "slp-max-insns-in-bb",
 965           "Maximum number of instructions in basic block to be considered for SLP vectorization.",
 966           1000, 0, 0)
 967
 968 DEFPARAM (PARAM_MIN_INSN_TO_PREFETCH_RATIO,
 969           "min-insn-to-prefetch-ratio",
 970           "Min. ratio of insns to prefetches to enable prefetching for "
 971           "a loop with an unknown trip count.",
 972           9, 0, 0)
 973
 974 DEFPARAM (PARAM_PREFETCH_MIN_INSN_TO_MEM_RATIO,
 975           "prefetch-min-insn-to-mem-ratio",
 976           "Min. ratio of insns to mem ops to enable prefetching in a loop.",
 977           3, 0, 0)
 978
 979 /* Set maximum hash table size for var tracking.  */
 980
 981 DEFPARAM (PARAM_MAX_VARTRACK_SIZE,
 982           "max-vartrack-size",
 983           "Max. size of var tracking hash tables.",
 984           50000000, 0, 0)
 985
 986 /* Set maximum recursion depth for var tracking expression expansion
 987    and resolution.  */
 988
 989 DEFPARAM (PARAM_MAX_VARTRACK_EXPR_DEPTH,
 990           "max-vartrack-expr-depth",
 991           "Max. recursion depth for expanding var tracking expressions.",
 992           12, 0, 0)
 993
 994 /* Set maximum length of value location list for which var tracking
 995    should add reverse operations.  */
 996
 997 DEFPARAM (PARAM_MAX_VARTRACK_REVERSE_OP_SIZE,
 998           "max-vartrack-reverse-op-size",
 999           "Max. size of loc list for which reverse ops should be added.",
1000           50, 0, 0)
1001
1002 /* Set a threshold to discard debug markers (e.g. debug begin stmt
1003    markers) when expanding a function to RTL, or inlining it into
1004    another function.  */
1005
1006 DEFPARAM (PARAM_MAX_DEBUG_MARKER_COUNT,
1007           "max-debug-marker-count",
1008           "Max. count of debug markers to expand or inline.",
1009           100000, 0, 0)
1010
1011 /* Set minimum insn uid for non-debug insns.  */
1012
1013 DEFPARAM (PARAM_MIN_NONDEBUG_INSN_UID,
1014           "min-nondebug-insn-uid",
1015           "The minimum UID to be used for a nondebug insn.",
1016           0, 0, 0)
1017
1018 DEFPARAM (PARAM_IPA_SRA_PTR_GROWTH_FACTOR,
1019           "ipa-sra-ptr-growth-factor",
1020           "Maximum allowed growth of number and total size of new parameters "
1021           "that ipa-sra replaces a pointer to an aggregate with.",
1022           2, 0, 0)
1023
1024 DEFPARAM (PARAM_TM_MAX_AGGREGATE_SIZE,
1025           "tm-max-aggregate-size",
1026           "Size in bytes after which thread-local aggregates should be "
1027           "instrumented with the logging functions instead of save/restore "
1028           "pairs.",
1029           9, 0, 0)
1030
1031 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SPEED,
1032           "sra-max-scalarization-size-Ospeed",
1033           "Maximum size, in storage units, of an aggregate which should be "
1034           "considered for scalarization when compiling for speed.",
1035           0, 0, 0)
1036
1037 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SIZE,
1038           "sra-max-scalarization-size-Osize",
1039           "Maximum size, in storage units, of an aggregate which should be "
1040           "considered for scalarization when compiling for size.",
1041           0, 0, 0)
1042
1043 DEFPARAM (PARAM_IPA_CP_VALUE_LIST_SIZE,
1044           "ipa-cp-value-list-size",
1045           "Maximum size of a list of values associated with each parameter for "
1046           "interprocedural constant propagation.",
1047           8, 0, 0)
1048
1049 DEFPARAM (PARAM_IPA_CP_EVAL_THRESHOLD,
1050           "ipa-cp-eval-threshold",
1051           "Threshold ipa-cp opportunity evaluation that is still considered "
1052           "beneficial to clone..",
1053           500, 0, 0)
1054
1055 DEFPARAM (PARAM_IPA_CP_RECURSION_PENALTY,
1056           "ipa-cp-recursion-penalty",
1057           "Percentage penalty the recursive functions will receive when they "
1058           "are evaluated for cloning..",
1059           40, 0, 100)
1060
1061 DEFPARAM (PARAM_IPA_CP_SINGLE_CALL_PENALTY,
1062           "ipa-cp-single-call-penalty",
1063           "Percentage penalty functions containing a single call to another "
1064           "function will receive when they are evaluated for cloning..",
1065           15, 0, 100)
1066
1067 DEFPARAM (PARAM_IPA_MAX_AGG_ITEMS,
1068           "ipa-max-agg-items",
1069           "Maximum number of aggregate content items for a parameter in "
1070           "jump functions and lattices.",
1071           16, 0, 0)
1072
1073 DEFPARAM (PARAM_IPA_CP_LOOP_HINT_BONUS,
1074           "ipa-cp-loop-hint-bonus",
1075           "Compile-time bonus IPA-CP assigns to candidates which make loop "
1076           "bounds or strides known..",
1077           64, 0, 0)
1078
1079 DEFPARAM (PARAM_IPA_CP_ARRAY_INDEX_HINT_BONUS,
1080           "ipa-cp-array-index-hint-bonus",
1081           "Compile-time bonus IPA-CP assigns to candidates which make an array "
1082           "index known..",
1083           48, 0, 0)
1084
1085 DEFPARAM (PARAM_IPA_MAX_AA_STEPS,
1086           "ipa-max-aa-steps",
1087           "Maximum number of statements that will be visited by IPA formal "
1088           "parameter analysis based on alias analysis in any given function.",
1089           25000, 0, 0)
1090
1091 /* WHOPR partitioning configuration.  */
1092
1093 DEFPARAM (PARAM_LTO_PARTITIONS,
1094           "lto-partitions",
1095           "Number of partitions the program should be split to.",
1096           32, 1, 0)
1097
1098 DEFPARAM (MIN_PARTITION_SIZE,
1099           "lto-min-partition",
1100           "Minimal size of a partition for LTO (in estimated instructions).",
1101           10000, 0, 0)
1102
1103 DEFPARAM (MAX_PARTITION_SIZE,
1104           "lto-max-partition",
1105           "Maximal size of a partition for LTO (in estimated instructions).",
1106           1000000, 0, INT_MAX)
1107
1108 /* Diagnostic parameters.  */
1109
1110 DEFPARAM (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP,
1111           "cxx-max-namespaces-for-diagnostic-help",
1112           "Maximum number of namespaces to search for alternatives when "
1113           "name lookup fails.",
1114           1000, 0, 0)
1115
1116 /* Maximum number of conditional store pairs that can be sunk.  */
1117 DEFPARAM (PARAM_MAX_STORES_TO_SINK,
1118           "max-stores-to-sink",
1119           "Maximum number of conditional store pairs that can be sunk.",
1120           2, 0, 0)
1121
1122 /* Override CASE_VALUES_THRESHOLD of when to switch from doing switch
1123    statements via if statements to using a table jump operation.  If the value
1124    is 0, the default CASE_VALUES_THRESHOLD will be used.  */
1125 DEFPARAM (PARAM_CASE_VALUES_THRESHOLD,
1126           "case-values-threshold",
1127           "The smallest number of different values for which it is best to "
1128           "use a jump-table instead of a tree of conditional branches, "
1129           "if 0, use the default for the machine.",
1130           0, 0, 0)
1131
1132 /* Data race flags for C++0x memory model compliance.  */
1133 DEFPARAM (PARAM_ALLOW_STORE_DATA_RACES,
1134           "allow-store-data-races",
1135           "Allow new data races on stores to be introduced.",
1136           0, 0, 1)
1137
1138 /* Reassociation width to be used by tree reassoc optimization.  */
1139 DEFPARAM (PARAM_TREE_REASSOC_WIDTH,
1140           "tree-reassoc-width",
1141           "Set the maximum number of instructions executed in parallel in "
1142           "reassociated tree. If 0, use the target dependent heuristic..",
1143           0, 0, 0)
1144
1145 DEFPARAM (PARAM_MAX_TAIL_MERGE_COMPARISONS,
1146           "max-tail-merge-comparisons",
1147           "Maximum amount of similar bbs to compare a bb with.",
1148           10, 0, 0)
1149
1150 DEFPARAM (PARAM_STORE_MERGING_ALLOW_UNALIGNED,
1151           "store-merging-allow-unaligned",
1152           "Allow the store merging pass to introduce unaligned stores "
1153           "if it is legal to do so.",
1154           1, 0, 1)
1155
1156 DEFPARAM (PARAM_MAX_STORES_TO_MERGE,
1157           "max-stores-to-merge",
1158           "Maximum number of constant stores to merge in the "
1159           "store merging pass.",
1160           64, 2, 0)
1161
1162 DEFPARAM (PARAM_MAX_TAIL_MERGE_ITERATIONS,
1163           "max-tail-merge-iterations",
1164           "Maximum amount of iterations of the pass over a function.",
1165           2, 0, 0)
1166
1167 /* Maximum number of strings for which strlen optimization pass will
1168    track string lenths.  */
1169 DEFPARAM (PARAM_MAX_TRACKED_STRLENS,
1170           "max-tracked-strlens",
1171           "Maximum number of strings for which strlen optimization pass will "
1172           "track string lengths.",
1173           10000, 0, 0)
1174
1175 /* Keep this in sync with the sched_pressure_algorithm enum.  */
1176 DEFPARAM (PARAM_SCHED_PRESSURE_ALGORITHM,
1177           "sched-pressure-algorithm",
1178           "Which -fsched-pressure algorithm to apply.",
1179           1, 1, 2)
1180
1181 /* Maximum length of candidate scans in straight-line strength reduction.  */
1182 DEFPARAM (PARAM_MAX_SLSR_CANDIDATE_SCAN,
1183           "max-slsr-cand-scan",
1184           "Maximum length of candidate scans for straight-line "
1185           "strength reduction.",
1186           50, 1, 999999)
1187
1188 DEFPARAM (PARAM_ASAN_STACK,
1189          "asan-stack",
1190          "Enable asan stack protection.",
1191          1, 0, 1)
1192
1193 DEFPARAM (PARAM_ASAN_PROTECT_ALLOCAS,
1194         "asan-instrument-allocas",
1195         "Enable asan allocas/VLAs protection.",
1196         1, 0, 1)
1197
1198 DEFPARAM (PARAM_ASAN_GLOBALS,
1199          "asan-globals",
1200          "Enable asan globals protection.",
1201          1, 0, 1)
1202
1203 DEFPARAM (PARAM_ASAN_INSTRUMENT_WRITES,
1204          "asan-instrument-writes",
1205          "Enable asan store operations protection.",
1206          1, 0, 1)
1207
1208 DEFPARAM (PARAM_ASAN_INSTRUMENT_READS,
1209          "asan-instrument-reads",
1210          "Enable asan load operations protection.",
1211          1, 0, 1)
1212
1213 DEFPARAM (PARAM_ASAN_MEMINTRIN,
1214          "asan-memintrin",
1215          "Enable asan builtin functions protection.",
1216          1, 0, 1)
1217
1218 DEFPARAM (PARAM_ASAN_USE_AFTER_RETURN,
1219          "asan-use-after-return",
1220          "Enable asan detection of use-after-return bugs.",
1221          1, 0, 1)
1222
1223 DEFPARAM (PARAM_ASAN_INSTRUMENTATION_WITH_CALL_THRESHOLD,
1224          "asan-instrumentation-with-call-threshold",
1225          "Use callbacks instead of inline code if number of accesses "
1226          "in function becomes greater or equal to this number.",
1227          7000, 0, INT_MAX)
1228
1229 DEFPARAM (PARAM_USE_AFTER_SCOPE_DIRECT_EMISSION_THRESHOLD,
1230          "use-after-scope-direct-emission-threshold",
1231          "Use direct poisoning/unpoisoning instructions for variables "
1232          "smaller or equal to this number.",
1233          256, 0, INT_MAX)
1234
1235 DEFPARAM (PARAM_UNINIT_CONTROL_DEP_ATTEMPTS,
1236           "uninit-control-dep-attempts",
1237           "Maximum number of nested calls to search for control dependencies "
1238           "during uninitialized variable analysis.",
1239           1000, 1, 0)
1240
1241 DEFPARAM (PARAM_FSM_SCALE_PATH_STMTS,
1242           "fsm-scale-path-stmts",
1243           "Scale factor to apply to the number of statements in a threading path when comparing to the number of (scaled) blocks.",
1244           2, 1, 10)
1245
1246 DEFPARAM (PARAM_FSM_MAXIMUM_PHI_ARGUMENTS,
1247           "fsm-maximum-phi-arguments",
1248           "Maximum number of arguments a PHI may have before the FSM threader will not try to thread through its block.",
1249           100, 1, 999999)
1250
1251 DEFPARAM (PARAM_FSM_SCALE_PATH_BLOCKS,
1252           "fsm-scale-path-blocks",
1253           "Scale factor to apply to the number of blocks in a threading path when comparing to the number of (scaled) statements.",
1254           3, 1, 10)
1255
1256 DEFPARAM (PARAM_MAX_FSM_THREAD_PATH_INSNS,
1257           "max-fsm-thread-path-insns",
1258           "Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path.",
1259           100, 1, 999999)
1260
1261 DEFPARAM (PARAM_MAX_FSM_THREAD_LENGTH,
1262           "max-fsm-thread-length",
1263           "Maximum number of basic blocks on a finite state automaton jump thread path.",
1264           10, 1, 999999)
1265
1266 DEFPARAM (PARAM_MAX_FSM_THREAD_PATHS,
1267           "max-fsm-thread-paths",
1268           "Maximum number of new jump thread paths to create for a finite state automaton.",
1269           50, 1, 999999)
1270
1271 DEFPARAM (PARAM_PARLOOPS_CHUNK_SIZE,
1272           "parloops-chunk-size",
1273           "Chunk size of omp schedule for loops parallelized by parloops.",
1274           0, 0, 0)
1275
1276 DEFPARAMENUM5 (PARAM_PARLOOPS_SCHEDULE,
1277                "parloops-schedule",
1278                "Schedule type of omp schedule for loops parallelized by "
1279                "parloops (static, dynamic, guided, auto, runtime).",
1280                static,
1281                static, dynamic, guided, auto, runtime)
1282
1283 DEFPARAM (PARAM_PARLOOPS_MIN_PER_THREAD,
1284           "parloops-min-per-thread",
1285           "Minimum number of iterations per thread of an innermost "
1286           "parallelized loop.",
1287           100, 2, 0)
1288
1289 DEFPARAM (PARAM_MAX_SSA_NAME_QUERY_DEPTH,
1290           "max-ssa-name-query-depth",
1291           "Maximum recursion depth allowed when querying a property of an"
1292           " SSA name.",
1293           3, 1, 10)
1294
1295 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_INSNS,
1296           "max-rtl-if-conversion-insns",
1297           "Maximum number of insns in a basic block to consider for RTL "
1298           "if-conversion.",
1299           10, 0, 99)
1300
1301 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_PREDICTABLE_COST,
1302           "max-rtl-if-conversion-predictable-cost",
1303           "Maximum permissible cost for the sequence that would be "
1304           "generated by the RTL if-conversion pass for a branch that "
1305           "is considered predictable.",
1306           20, 0, 200)
1307
1308 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_UNPREDICTABLE_COST,
1309           "max-rtl-if-conversion-unpredictable-cost",
1310           "Maximum permissible cost for the sequence that would be "
1311           "generated by the RTL if-conversion pass for a branch that "
1312           "is considered unpredictable.",
1313           40, 0, 200)
1314
1315 DEFPARAM (PARAM_HSA_GEN_DEBUG_STORES,
1316           "hsa-gen-debug-stores",
1317           "Level of hsa debug stores verbosity",
1318           0, 0, 1)
1319
1320 DEFPARAM (PARAM_MAX_SPECULATIVE_DEVIRT_MAYDEFS,
1321           "max-speculative-devirt-maydefs",
1322           "Maximum number of may-defs visited when devirtualizing "
1323           "speculatively", 50, 0, 0)
1324
1325 DEFPARAM (PARAM_MAX_VRP_SWITCH_ASSERTIONS,
1326           "max-vrp-switch-assertions",
1327           "Maximum number of assertions to add along the default "
1328           "edge of a switch statement during VRP",
1329           10, 0, 0)
1330
1331 DEFPARAM (PARAM_VECT_EPILOGUES_NOMASK,
1332           "vect-epilogues-nomask",
1333           "Enable loop epilogue vectorization using smaller vector size.",
1334           0, 0, 1)
1335
1336 DEFPARAM(PARAM_UNROLL_JAM_MIN_PERCENT,
1337          "unroll-jam-min-percent",
1338          "Minimum percentage of memrefs that must go away for unroll-and-jam to be considered profitable.",
1339          1, 0, 100)
1340
1341 DEFPARAM(PARAM_UNROLL_JAM_MAX_UNROLL,
1342          "unroll-jam-max-unroll",
1343          "Maximum unroll factor for the unroll-and-jam transformation.",
1344          4, 0, 0)
1345
1346 DEFPARAM(PARAM_AVOID_FMA_MAX_BITS,
1347          "avoid-fma-max-bits",
1348          "Maximum number of bits for which we avoid creating FMAs.",
1349          0, 0, 512)
1350
1351 /*
1352
1353 Local variables:
1354 mode:c
1355 End:
1356 */