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 he 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 he 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_SCEV_MAX_EXPR_SIZE,
 551          "scev-max-expr-size",
 552          "Bound on size of expressions used in the scalar evolutions analyzer.",
 553          100, 0, 0)
 554
 555 DEFPARAM(PARAM_SCEV_MAX_EXPR_COMPLEXITY,
 556          "scev-max-expr-complexity",
 557          "Bound on the complexity of the expressions in the scalar evolutions analyzer.",
 558          10, 0, 0)
 559
 560 DEFPARAM (PARAM_MAX_TREE_IF_CONVERSION_PHI_ARGS,
 561           "max-tree-if-conversion-phi-args",
 562           "Maximum number of arguments in a PHI supported by TREE if-conversion "
 563           "unless the loop is marked with simd pragma.",
 564           4, 2, 0)
 565
 566 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS,
 567          "vect-max-version-for-alignment-checks",
 568          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check.",
 569          6, 0, 0)
 570
 571 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS,
 572          "vect-max-version-for-alias-checks",
 573          "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check.",
 574          10, 0, 0)
 575
 576 DEFPARAM(PARAM_VECT_MAX_PEELING_FOR_ALIGNMENT,
 577          "vect-max-peeling-for-alignment",
 578          "Maximum number of loop peels to enhance alignment of data references in a loop.",
 579          -1, -1, 64)
 580
 581 DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
 582          "max-cselib-memory-locations",
 583          "The maximum memory locations recorded by cselib.",
 584          500, 0, 0)
 585
 586 #ifdef ENABLE_GC_ALWAYS_COLLECT
 587 # define GGC_MIN_EXPAND_DEFAULT 0
 588 # define GGC_MIN_HEAPSIZE_DEFAULT 0
 589 #else
 590 # define GGC_MIN_EXPAND_DEFAULT 30
 591 # define GGC_MIN_HEAPSIZE_DEFAULT 4096
 592 #endif
 593
 594 DEFPARAM(GGC_MIN_EXPAND,
 595          "ggc-min-expand",
 596          "Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap.",
 597          GGC_MIN_EXPAND_DEFAULT, 0, 0)
 598
 599 DEFPARAM(GGC_MIN_HEAPSIZE,
 600          "ggc-min-heapsize",
 601          "Minimum heap size before we start collecting garbage, in kilobytes.",
 602          GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
 603
 604 #undef GGC_MIN_EXPAND_DEFAULT
 605 #undef GGC_MIN_HEAPSIZE_DEFAULT
 606
 607 DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
 608          "max-reload-search-insns",
 609          "The maximum number of instructions to search backward when looking for equivalent reload.",
 610          100, 0, 0)
 611
 612 DEFPARAM(PARAM_SINK_FREQUENCY_THRESHOLD,
 613          "sink-frequency-threshold",
 614          "Target block's relative execution frequency (as a percentage) required to sink a statement.",
 615          75, 0, 100)
 616
 617 DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
 618          "max-sched-region-blocks",
 619          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 620          10, 0, 0)
 621
 622 DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
 623          "max-sched-region-insns",
 624          "The maximum number of insns in a region to be considered for interblock scheduling.",
 625          100, 0, 0)
 626
 627 DEFPARAM(PARAM_MAX_PIPELINE_REGION_BLOCKS,
 628          "max-pipeline-region-blocks",
 629          "The maximum number of blocks in a region to be considered for interblock scheduling.",
 630          15, 0, 0)
 631
 632 DEFPARAM(PARAM_MAX_PIPELINE_REGION_INSNS,
 633          "max-pipeline-region-insns",
 634          "The maximum number of insns in a region to be considered for interblock scheduling.",
 635          200, 0, 0)
 636
 637 DEFPARAM(PARAM_MIN_SPEC_PROB,
 638          "min-spec-prob",
 639          "The minimum probability of reaching a source block for interblock speculative scheduling.",
 640          40, 0, 0)
 641
 642 DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
 643          "max-sched-extend-regions-iters",
 644          "The maximum number of iterations through CFG to extend regions.",
 645          0, 0, 0)
 646
 647 DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
 648          "max-sched-insn-conflict-delay",
 649          "The maximum conflict delay for an insn to be considered for speculative motion.",
 650          3, 1, 10)
 651
 652 DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
 653          "sched-spec-prob-cutoff",
 654          "The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
 655          40, 0, 100)
 656
 657 DEFPARAM(PARAM_SCHED_STATE_EDGE_PROB_CUTOFF,
 658          "sched-state-edge-prob-cutoff",
 659          "The minimum probability an edge must have for the scheduler to save its state across it.",
 660          10, 0, 100)
 661
 662 DEFPARAM(PARAM_SELSCHED_MAX_LOOKAHEAD,
 663          "selsched-max-lookahead",
 664          "The maximum size of the lookahead window of selective scheduling.",
 665          50, 0, 0)
 666
 667 DEFPARAM(PARAM_SELSCHED_MAX_SCHED_TIMES,
 668          "selsched-max-sched-times",
 669          "Maximum number of times that an insn could be scheduled.",
 670          2, 1, 0)
 671
 672 DEFPARAM(PARAM_SELSCHED_INSNS_TO_RENAME,
 673          "selsched-insns-to-rename",
 674          "Maximum number of instructions in the ready list that are considered eligible for renaming.",
 675          2, 0, 0)
 676
 677 DEFPARAM (PARAM_SCHED_MEM_TRUE_DEP_COST,
 678           "sched-mem-true-dep-cost",
 679           "Minimal distance between possibly conflicting store and load.",
 680           1, 0, 0)
 681
 682 DEFPARAM (PARAM_SCHED_AUTOPREF_QUEUE_DEPTH,
 683           "sched-autopref-queue-depth",
 684           "Hardware autoprefetcher scheduler model control flag.  Number of lookahead cycles the model looks into; at '0' only enable instruction sorting heuristic.  Disabled by default.",
 685           -1, 0, 0)
 686
 687 DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
 688          "max-last-value-rtl",
 689          "The maximum number of RTL nodes that can be recorded as combiner's last value.",
 690          10000, 0, 0)
 691
 692 DEFPARAM(PARAM_MAX_COMBINE_INSNS,
 693          "max-combine-insns",
 694          "The maximum number of insns combine tries to combine.",
 695          4, 2, 4)
 696
 697 /* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
 698    {signed,unsigned} integral types.  This determines N.
 699    Experimentation shows 251 to be a good value that generates the
 700    least amount of garbage for allocating the TREE_VEC storage.  */
 701 DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
 702           "integer-share-limit",
 703           "The upper bound for sharing integer constants.",
 704           251, 2, 2)
 705
 706 DEFPARAM (PARAM_SSP_BUFFER_SIZE,
 707           "ssp-buffer-size",
 708           "The lower bound for a buffer to be considered for stack smashing protection.",
 709           8, 1, 0)
 710
 711 DEFPARAM (PARAM_MIN_SIZE_FOR_STACK_SHARING,
 712           "min-size-for-stack-sharing",
 713           "The minimum size of variables taking part in stack slot sharing "
 714           "when not optimizing.",
 715           32, 0, 0)
 716
 717 /* When we thread through a block we have to make copies of the
 718    statements within the block.  Clearly for large blocks the code
 719    duplication is bad.
 720
 721    PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
 722    of statements and PHI nodes allowed in a block which is going to
 723    be duplicated for thread jumping purposes.
 724
 725    Some simple analysis showed that more than 99% of the jump
 726    threading opportunities are for blocks with less than 15
 727    statements.  So we can get the benefits of jump threading
 728    without excessive code bloat for pathological cases with the
 729    throttle set at 15 statements.  */
 730 DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
 731           "max-jump-thread-duplication-stmts",
 732           "Maximum number of statements allowed in a block that needs to be duplicated when threading jumps.",
 733           15, 0, 0)
 734
 735 /* This is the maximum number of fields a variable may have before the pointer analysis machinery
 736    will stop trying to treat it in a field-sensitive manner.
 737    There are programs out there with thousands of fields per structure, and handling them
 738    field-sensitively is not worth the cost.  */
 739 DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
 740           "max-fields-for-field-sensitive",
 741           "Maximum number of fields in a structure before pointer analysis treats the structure as a single variable.",
 742           0, 0, 0)
 743
 744 DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
 745          "max-sched-ready-insns",
 746          "The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass.",
 747          100, 1, 0)
 748
 749 /* This is the maximum number of active local stores RTL DSE will consider.  */
 750 DEFPARAM (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES,
 751           "max-dse-active-local-stores",
 752           "Maximum number of active local stores in RTL dead store elimination.",
 753           5000, 0, 0)
 754
 755 /* Prefetching and cache-optimizations related parameters.  Default values are
 756    usually set by machine description.  */
 757
 758 /* The number of insns executed before prefetch is completed.  */
 759
 760 DEFPARAM (PARAM_PREFETCH_LATENCY,
 761          "prefetch-latency",
 762          "The number of insns executed before prefetch is completed.",
 763          200, 0, 0)
 764
 765 /* The number of prefetches that can run at the same time.  */
 766
 767 DEFPARAM (PARAM_SIMULTANEOUS_PREFETCHES,
 768           "simultaneous-prefetches",
 769           "The number of prefetches that can run at the same time.",
 770           3, 0, 0)
 771
 772 /* The size of L1 cache in kB.  */
 773
 774 DEFPARAM (PARAM_L1_CACHE_SIZE,
 775           "l1-cache-size",
 776           "The size of L1 cache.",
 777           64, 0, 0)
 778
 779 /* The size of L1 cache line in bytes.  */
 780
 781 DEFPARAM (PARAM_L1_CACHE_LINE_SIZE,
 782           "l1-cache-line-size",
 783           "The size of L1 cache line.",
 784           32, 0, 0)
 785
 786 /* The size of L2 cache in kB.  */
 787
 788 DEFPARAM (PARAM_L2_CACHE_SIZE,
 789           "l2-cache-size",
 790           "The size of L2 cache.",
 791           512, 0, 0)
 792
 793 /* Maximum number of statements in loop nest for loop interchange.  */
 794
 795 DEFPARAM (PARAM_LOOP_INTERCHANGE_MAX_NUM_STMTS,
 796           "loop-interchange-max-num-stmts",
 797           "The maximum number of stmts in loop nest for loop interchange.",
 798           64, 0, 0)
 799
 800 /* Minimum stride ratio for loop interchange to be profitiable.  */
 801
 802 DEFPARAM (PARAM_LOOP_INTERCHANGE_STRIDE_RATIO,
 803           "loop-interchange-stride-ratio",
 804           "The minimum stride ratio for loop interchange to be profitable",
 805           2, 0, 0)
 806
 807 /* Whether we should use canonical types rather than deep "structural"
 808    type checking.  Setting this value to 1 (the default) improves
 809    compilation performance in the C++ and Objective-C++ front end;
 810    this value should only be set to zero to work around bugs in the
 811    canonical type system by disabling it.  */
 812
 813 DEFPARAM (PARAM_USE_CANONICAL_TYPES,
 814           "use-canonical-types",
 815           "Whether to use canonical types.",
 816           1, 0, 1)
 817
 818 DEFPARAM (PARAM_MAX_PARTIAL_ANTIC_LENGTH,
 819           "max-partial-antic-length",
 820           "Maximum length of partial antic set when performing tree pre optimization.",
 821           100, 0, 0)
 822
 823 /* The following is used as a stop-gap limit for cases where really huge
 824    SCCs blow up memory and compile-time use too much.  If we hit this limit,
 825    SCCVN and such FRE and PRE will be not done at all for the current
 826    function.  */
 827
 828 DEFPARAM (PARAM_SCCVN_MAX_SCC_SIZE,
 829           "sccvn-max-scc-size",
 830           "Maximum size of a SCC before SCCVN stops processing a function.",
 831           10000, 10, 0)
 832
 833 /* The following is used as a stop-gap limit for cases where really huge
 834    functions blow up compile-time use too much.  It limits the number of
 835    alias-queries we do for finding common subexpressions for memory loads and
 836    stores.  The number of alias-queries is otherwise limited by the number of
 837    stores on paths to function entry.  */
 838
 839 DEFPARAM (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS,
 840           "sccvn-max-alias-queries-per-access",
 841           "Maximum number of disambiguations to perform per memory access.",
 842           1000, 0, 0)
 843
 844 DEFPARAM (PARAM_IRA_MAX_LOOPS_NUM,
 845           "ira-max-loops-num",
 846           "Max loops number for regional RA.",
 847           100, 0, 0)
 848
 849 DEFPARAM (PARAM_IRA_MAX_CONFLICT_TABLE_SIZE,
 850           "ira-max-conflict-table-size",
 851           "Max size of conflict table in MB.",
 852           1000, 0, 0)
 853
 854 DEFPARAM (PARAM_IRA_LOOP_RESERVED_REGS,
 855           "ira-loop-reserved-regs",
 856           "The number of registers in each class kept unused by loop invariant motion.",
 857           2, 0, 0)
 858
 859 DEFPARAM (PARAM_LRA_MAX_CONSIDERED_RELOAD_PSEUDOS,
 860           "lra-max-considered-reload-pseudos",
 861           "The max number of reload pseudos which are considered during spilling a non-reload pseudo.",
 862           500, 0, 0)
 863
 864 DEFPARAM (PARAM_LRA_INHERITANCE_EBB_PROBABILITY_CUTOFF,
 865           "lra-inheritance-ebb-probability-cutoff",
 866           "Minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA.",
 867           40, 0, 100)
 868
 869 /* Switch initialization conversion will refuse to create arrays that are
 870    bigger than this parameter times the number of switch branches.  */
 871
 872 DEFPARAM (PARAM_SWITCH_CONVERSION_BRANCH_RATIO,
 873           "switch-conversion-max-branch-ratio",
 874           "The maximum ratio between array size and switch branches for "
 875           "a switch conversion to take place.",
 876           8, 1, 0)
 877
 878 /* Size of tiles when doing loop blocking.  */
 879
 880 DEFPARAM (PARAM_LOOP_BLOCK_TILE_SIZE,
 881           "loop-block-tile-size",
 882           "size of tiles for loop blocking.",
 883           51, 0, 0)
 884
 885 /* Maximal number of parameters that we allow in a SCoP.  */
 886
 887 DEFPARAM (PARAM_GRAPHITE_MAX_NB_SCOP_PARAMS,
 888           "graphite-max-nb-scop-params",
 889           "maximum number of parameters in a SCoP.",
 890           10, 0, 0)
 891
 892 /* Maximal number of array references in a scop.  */
 893
 894 DEFPARAM (PARAM_GRAPHITE_MAX_ARRAYS_PER_SCOP,
 895           "graphite-max-arrays-per-scop",
 896           "maximum number of arrays per scop.",
 897           100, 0, 0)
 898
 899 DEFPARAM (PARAM_MAX_ISL_OPERATIONS,
 900           "max-isl-operations",
 901           "maximum number of isl operations, 0 means unlimited",
 902           350000, 0, 0)
 903
 904 /* For testsuite purposes allow to check for codegen error handling.  */
 905 DEFPARAM (PARAM_GRAPHITE_ALLOW_CODEGEN_ERRORS,
 906           "graphite-allow-codegen-errors",
 907           "whether codegen errors should be ICEs when -fchecking.",
 908           0, 0, 1)
 909
 910 /* Avoid data dependence analysis on very large loops.  */
 911 DEFPARAM (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS,
 912           "loop-max-datarefs-for-datadeps",
 913           "Maximum number of datarefs in loop for building loop data dependencies.",
 914           1000, 0, 0)
 915
 916 /* Avoid doing loop invariant motion on very large loops.  */
 917
 918 DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_IN_LOOP,
 919           "loop-invariant-max-bbs-in-loop",
 920           "Max basic blocks number in loop for loop invariant motion.",
 921           10000, 0, 0)
 922
 923 /* When the parameter is 1, use the internal function id
 924    to look up for profile data. Otherwise, use a more stable
 925    external id based on assembler name and source location. */
 926 DEFPARAM (PARAM_PROFILE_FUNC_INTERNAL_ID,
 927          "profile-func-internal-id",
 928          "use internal function id in profile lookup.",
 929           0, 0, 1)
 930
 931 /* When the parameter is 1, track the most frequent N target
 932    addresses in indirect-call profile. This disables
 933    indirect_call_profiler_v2 which tracks single target.  */
 934 DEFPARAM (PARAM_INDIR_CALL_TOPN_PROFILE,
 935          "indir-call-topn-profile",
 936          "track topn target addresses in indirect-call profile.",
 937           0, 0, 1)
 938
 939 /* Avoid SLP vectorization of large basic blocks.  */
 940 DEFPARAM (PARAM_SLP_MAX_INSNS_IN_BB,
 941           "slp-max-insns-in-bb",
 942           "Maximum number of instructions in basic block to be considered for SLP vectorization.",
 943           1000, 0, 0)
 944
 945 DEFPARAM (PARAM_MIN_INSN_TO_PREFETCH_RATIO,
 946           "min-insn-to-prefetch-ratio",
 947           "Min. ratio of insns to prefetches to enable prefetching for "
 948           "a loop with an unknown trip count.",
 949           9, 0, 0)
 950
 951 DEFPARAM (PARAM_PREFETCH_MIN_INSN_TO_MEM_RATIO,
 952           "prefetch-min-insn-to-mem-ratio",
 953           "Min. ratio of insns to mem ops to enable prefetching in a loop.",
 954           3, 0, 0)
 955
 956 /* Set maximum hash table size for var tracking.  */
 957
 958 DEFPARAM (PARAM_MAX_VARTRACK_SIZE,
 959           "max-vartrack-size",
 960           "Max. size of var tracking hash tables.",
 961           50000000, 0, 0)
 962
 963 /* Set maximum recursion depth for var tracking expression expansion
 964    and resolution.  */
 965
 966 DEFPARAM (PARAM_MAX_VARTRACK_EXPR_DEPTH,
 967           "max-vartrack-expr-depth",
 968           "Max. recursion depth for expanding var tracking expressions.",
 969           12, 0, 0)
 970
 971 /* Set maximum length of value location list for which var tracking
 972    should add reverse operations.  */
 973
 974 DEFPARAM (PARAM_MAX_VARTRACK_REVERSE_OP_SIZE,
 975           "max-vartrack-reverse-op-size",
 976           "Max. size of loc list for which reverse ops should be added.",
 977           50, 0, 0)
 978
 979 /* Set a threshold to discard debug markers (e.g. debug begin stmt
 980    markers) when expanding a function to RTL, or inlining it into
 981    another function.  */
 982
 983 DEFPARAM (PARAM_MAX_DEBUG_MARKER_COUNT,
 984           "max-debug-marker-count",
 985           "Max. count of debug markers to expand or inline.",
 986           100000, 0, 0)
 987
 988 /* Set minimum insn uid for non-debug insns.  */
 989
 990 DEFPARAM (PARAM_MIN_NONDEBUG_INSN_UID,
 991           "min-nondebug-insn-uid",
 992           "The minimum UID to be used for a nondebug insn.",
 993           0, 0, 0)
 994
 995 DEFPARAM (PARAM_IPA_SRA_PTR_GROWTH_FACTOR,
 996           "ipa-sra-ptr-growth-factor",
 997           "Maximum allowed growth of number and total size of new parameters "
 998           "that ipa-sra replaces a pointer to an aggregate with.",
 999           2, 0, 0)
1000
1001 DEFPARAM (PARAM_TM_MAX_AGGREGATE_SIZE,
1002           "tm-max-aggregate-size",
1003           "Size in bytes after which thread-local aggregates should be "
1004           "instrumented with the logging functions instead of save/restore "
1005           "pairs.",
1006           9, 0, 0)
1007
1008 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SPEED,
1009           "sra-max-scalarization-size-Ospeed",
1010           "Maximum size, in storage units, of an aggregate which should be "
1011           "considered for scalarization when compiling for speed.",
1012           0, 0, 0)
1013
1014 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SIZE,
1015           "sra-max-scalarization-size-Osize",
1016           "Maximum size, in storage units, of an aggregate which should be "
1017           "considered for scalarization when compiling for size.",
1018           0, 0, 0)
1019
1020 DEFPARAM (PARAM_IPA_CP_VALUE_LIST_SIZE,
1021           "ipa-cp-value-list-size",
1022           "Maximum size of a list of values associated with each parameter for "
1023           "interprocedural constant propagation.",
1024           8, 0, 0)
1025
1026 DEFPARAM (PARAM_IPA_CP_EVAL_THRESHOLD,
1027           "ipa-cp-eval-threshold",
1028           "Threshold ipa-cp opportunity evaluation that is still considered "
1029           "beneficial to clone..",
1030           500, 0, 0)
1031
1032 DEFPARAM (PARAM_IPA_CP_RECURSION_PENALTY,
1033           "ipa-cp-recursion-penalty",
1034           "Percentage penalty the recursive functions will receive when they "
1035           "are evaluated for cloning..",
1036           40, 0, 100)
1037
1038 DEFPARAM (PARAM_IPA_CP_SINGLE_CALL_PENALTY,
1039           "ipa-cp-single-call-penalty",
1040           "Percentage penalty functions containing a single call to another "
1041           "function will receive when they are evaluated for cloning..",
1042           15, 0, 100)
1043
1044 DEFPARAM (PARAM_IPA_MAX_AGG_ITEMS,
1045           "ipa-max-agg-items",
1046           "Maximum number of aggregate content items for a parameter in "
1047           "jump functions and lattices.",
1048           16, 0, 0)
1049
1050 DEFPARAM (PARAM_IPA_CP_LOOP_HINT_BONUS,
1051           "ipa-cp-loop-hint-bonus",
1052           "Compile-time bonus IPA-CP assigns to candidates which make loop "
1053           "bounds or strides known..",
1054           64, 0, 0)
1055
1056 DEFPARAM (PARAM_IPA_CP_ARRAY_INDEX_HINT_BONUS,
1057           "ipa-cp-array-index-hint-bonus",
1058           "Compile-time bonus IPA-CP assigns to candidates which make an array "
1059           "index known..",
1060           48, 0, 0)
1061
1062 DEFPARAM (PARAM_IPA_MAX_AA_STEPS,
1063           "ipa-max-aa-steps",
1064           "Maximum number of statements that will be visited by IPA formal "
1065           "parameter analysis based on alias analysis in any given function.",
1066           25000, 0, 0)
1067
1068 /* WHOPR partitioning configuration.  */
1069
1070 DEFPARAM (PARAM_LTO_PARTITIONS,
1071           "lto-partitions",
1072           "Number of partitions the program should be split to.",
1073           32, 1, 0)
1074
1075 DEFPARAM (MIN_PARTITION_SIZE,
1076           "lto-min-partition",
1077           "Minimal size of a partition for LTO (in estimated instructions).",
1078           10000, 0, 0)
1079
1080 DEFPARAM (MAX_PARTITION_SIZE,
1081           "lto-max-partition",
1082           "Maximal size of a partition for LTO (in estimated instructions).",
1083           1000000, 0, INT_MAX)
1084
1085 /* Diagnostic parameters.  */
1086
1087 DEFPARAM (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP,
1088           "cxx-max-namespaces-for-diagnostic-help",
1089           "Maximum number of namespaces to search for alternatives when "
1090           "name lookup fails.",
1091           1000, 0, 0)
1092
1093 /* Maximum number of conditional store pairs that can be sunk.  */
1094 DEFPARAM (PARAM_MAX_STORES_TO_SINK,
1095           "max-stores-to-sink",
1096           "Maximum number of conditional store pairs that can be sunk.",
1097           2, 0, 0)
1098
1099 /* Override CASE_VALUES_THRESHOLD of when to switch from doing switch
1100    statements via if statements to using a table jump operation.  If the value
1101    is 0, the default CASE_VALUES_THRESHOLD will be used.  */
1102 DEFPARAM (PARAM_CASE_VALUES_THRESHOLD,
1103           "case-values-threshold",
1104           "The smallest number of different values for which it is best to "
1105           "use a jump-table instead of a tree of conditional branches, "
1106           "if 0, use the default for the machine.",
1107           0, 0, 0)
1108
1109 /* Data race flags for C++0x memory model compliance.  */
1110 DEFPARAM (PARAM_ALLOW_STORE_DATA_RACES,
1111           "allow-store-data-races",
1112           "Allow new data races on stores to be introduced.",
1113           0, 0, 1)
1114
1115 /* Reassociation width to be used by tree reassoc optimization.  */
1116 DEFPARAM (PARAM_TREE_REASSOC_WIDTH,
1117           "tree-reassoc-width",
1118           "Set the maximum number of instructions executed in parallel in "
1119           "reassociated tree. If 0, use the target dependent heuristic..",
1120           0, 0, 0)
1121
1122 DEFPARAM (PARAM_MAX_TAIL_MERGE_COMPARISONS,
1123           "max-tail-merge-comparisons",
1124           "Maximum amount of similar bbs to compare a bb with.",
1125           10, 0, 0)
1126
1127 DEFPARAM (PARAM_STORE_MERGING_ALLOW_UNALIGNED,
1128           "store-merging-allow-unaligned",
1129           "Allow the store merging pass to introduce unaligned stores "
1130           "if it is legal to do so.",
1131           1, 0, 1)
1132
1133 DEFPARAM (PARAM_MAX_STORES_TO_MERGE,
1134           "max-stores-to-merge",
1135           "Maximum number of constant stores to merge in the "
1136           "store merging pass.",
1137           64, 2, 0)
1138
1139 DEFPARAM (PARAM_MAX_TAIL_MERGE_ITERATIONS,
1140           "max-tail-merge-iterations",
1141           "Maximum amount of iterations of the pass over a function.",
1142           2, 0, 0)
1143
1144 /* Maximum number of strings for which strlen optimization pass will
1145    track string lenths.  */
1146 DEFPARAM (PARAM_MAX_TRACKED_STRLENS,
1147           "max-tracked-strlens",
1148           "Maximum number of strings for which strlen optimization pass will "
1149           "track string lengths.",
1150           10000, 0, 0)
1151
1152 /* Keep this in sync with the sched_pressure_algorithm enum.  */
1153 DEFPARAM (PARAM_SCHED_PRESSURE_ALGORITHM,
1154           "sched-pressure-algorithm",
1155           "Which -fsched-pressure algorithm to apply.",
1156           1, 1, 2)
1157
1158 /* Maximum length of candidate scans in straight-line strength reduction.  */
1159 DEFPARAM (PARAM_MAX_SLSR_CANDIDATE_SCAN,
1160           "max-slsr-cand-scan",
1161           "Maximum length of candidate scans for straight-line "
1162           "strength reduction.",
1163           50, 1, 999999)
1164
1165 DEFPARAM (PARAM_ASAN_STACK,
1166          "asan-stack",
1167          "Enable asan stack protection.",
1168          1, 0, 1)
1169
1170 DEFPARAM (PARAM_ASAN_PROTECT_ALLOCAS,
1171         "asan-instrument-allocas",
1172         "Enable asan allocas/VLAs protection.",
1173         1, 0, 1)
1174
1175 DEFPARAM (PARAM_ASAN_GLOBALS,
1176          "asan-globals",
1177          "Enable asan globals protection.",
1178          1, 0, 1)
1179
1180 DEFPARAM (PARAM_ASAN_INSTRUMENT_WRITES,
1181          "asan-instrument-writes",
1182          "Enable asan store operations protection.",
1183          1, 0, 1)
1184
1185 DEFPARAM (PARAM_ASAN_INSTRUMENT_READS,
1186          "asan-instrument-reads",
1187          "Enable asan load operations protection.",
1188          1, 0, 1)
1189
1190 DEFPARAM (PARAM_ASAN_MEMINTRIN,
1191          "asan-memintrin",
1192          "Enable asan builtin functions protection.",
1193          1, 0, 1)
1194
1195 DEFPARAM (PARAM_ASAN_USE_AFTER_RETURN,
1196          "asan-use-after-return",
1197          "Enable asan detection of use-after-return bugs.",
1198          1, 0, 1)
1199
1200 DEFPARAM (PARAM_ASAN_INSTRUMENTATION_WITH_CALL_THRESHOLD,
1201          "asan-instrumentation-with-call-threshold",
1202          "Use callbacks instead of inline code if number of accesses "
1203          "in function becomes greater or equal to this number.",
1204          7000, 0, INT_MAX)
1205
1206 DEFPARAM (PARAM_USE_AFTER_SCOPE_DIRECT_EMISSION_THRESHOLD,
1207          "use-after-scope-direct-emission-threshold",
1208          "Use direct poisoning/unpoisoning instructions for variables "
1209          "smaller or equal to this number.",
1210          256, 0, INT_MAX)
1211
1212 DEFPARAM (PARAM_UNINIT_CONTROL_DEP_ATTEMPTS,
1213           "uninit-control-dep-attempts",
1214           "Maximum number of nested calls to search for control dependencies "
1215           "during uninitialized variable analysis.",
1216           1000, 1, 0)
1217
1218 DEFPARAM (PARAM_CHKP_MAX_CTOR_SIZE,
1219           "chkp-max-ctor-size",
1220           "Maximum number of statements to be included into a single static "
1221           "constructor generated by Pointer Bounds Checker.",
1222           5000, 100, 0)
1223
1224 DEFPARAM (PARAM_FSM_SCALE_PATH_STMTS,
1225           "fsm-scale-path-stmts",
1226           "Scale factor to apply to the number of statements in a threading path when comparing to the number of (scaled) blocks.",
1227           2, 1, 10)
1228
1229 DEFPARAM (PARAM_FSM_MAXIMUM_PHI_ARGUMENTS,
1230           "fsm-maximum-phi-arguments",
1231           "Maximum number of arguments a PHI may have before the FSM threader will not try to thread through its block.",
1232           100, 1, 999999)
1233
1234 DEFPARAM (PARAM_FSM_SCALE_PATH_BLOCKS,
1235           "fsm-scale-path-blocks",
1236           "Scale factor to apply to the number of blocks in a threading path when comparing to the number of (scaled) statements.",
1237           3, 1, 10)
1238
1239 DEFPARAM (PARAM_MAX_FSM_THREAD_PATH_INSNS,
1240           "max-fsm-thread-path-insns",
1241           "Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path.",
1242           100, 1, 999999)
1243
1244 DEFPARAM (PARAM_MAX_FSM_THREAD_LENGTH,
1245           "max-fsm-thread-length",
1246           "Maximum number of basic blocks on a finite state automaton jump thread path.",
1247           10, 1, 999999)
1248
1249 DEFPARAM (PARAM_MAX_FSM_THREAD_PATHS,
1250           "max-fsm-thread-paths",
1251           "Maximum number of new jump thread paths to create for a finite state automaton.",
1252           50, 1, 999999)
1253
1254 DEFPARAM (PARAM_PARLOOPS_CHUNK_SIZE,
1255           "parloops-chunk-size",
1256           "Chunk size of omp schedule for loops parallelized by parloops.",
1257           0, 0, 0)
1258
1259 DEFPARAMENUM5 (PARAM_PARLOOPS_SCHEDULE,
1260                "parloops-schedule",
1261                "Schedule type of omp schedule for loops parallelized by "
1262                "parloops (static, dynamic, guided, auto, runtime).",
1263                static,
1264                static, dynamic, guided, auto, runtime)
1265
1266 DEFPARAM (PARAM_PARLOOPS_MIN_PER_THREAD,
1267           "parloops-min-per-thread",
1268           "Minimum number of iterations per thread of an innermost "
1269           "parallelized loop.",
1270           100, 2, 0)
1271
1272 DEFPARAM (PARAM_MAX_SSA_NAME_QUERY_DEPTH,
1273           "max-ssa-name-query-depth",
1274           "Maximum recursion depth allowed when querying a property of an"
1275           " SSA name.",
1276           3, 1, 10)
1277
1278 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_INSNS,
1279           "max-rtl-if-conversion-insns",
1280           "Maximum number of insns in a basic block to consider for RTL "
1281           "if-conversion.",
1282           10, 0, 99)
1283
1284 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_PREDICTABLE_COST,
1285           "max-rtl-if-conversion-predictable-cost",
1286           "Maximum permissible cost for the sequence that would be "
1287           "generated by the RTL if-conversion pass for a branch that "
1288           "is considered predictable.",
1289           20, 0, 200)
1290
1291 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_UNPREDICTABLE_COST,
1292           "max-rtl-if-conversion-unpredictable-cost",
1293           "Maximum permissible cost for the sequence that would be "
1294           "generated by the RTL if-conversion pass for a branch that "
1295           "is considered unpredictable.",
1296           40, 0, 200)
1297
1298 DEFPARAM (PARAM_HSA_GEN_DEBUG_STORES,
1299           "hsa-gen-debug-stores",
1300           "Level of hsa debug stores verbosity",
1301           0, 0, 1)
1302
1303 DEFPARAM (PARAM_MAX_SPECULATIVE_DEVIRT_MAYDEFS,
1304           "max-speculative-devirt-maydefs",
1305           "Maximum number of may-defs visited when devirtualizing "
1306           "speculatively", 50, 0, 0)
1307
1308 DEFPARAM (PARAM_MAX_VRP_SWITCH_ASSERTIONS,
1309           "max-vrp-switch-assertions",
1310           "Maximum number of assertions to add along the default "
1311           "edge of a switch statement during VRP",
1312           10, 0, 0)
1313
1314 DEFPARAM (PARAM_VECT_EPILOGUES_NOMASK,
1315           "vect-epilogues-nomask",
1316           "Enable loop epilogue vectorization using smaller vector size.",
1317           0, 0, 1)
1318
1319 DEFPARAM(PARAM_UNROLL_JAM_MIN_PERCENT,
1320          "unroll-jam-min-percent",
1321          "Minimum percentage of memrefs that must go away for unroll-and-jam to be considered profitable.",
1322          1, 0, 100)
1323
1324 DEFPARAM(PARAM_UNROLL_JAM_MAX_UNROLL,
1325          "unroll-jam-max-unroll",
1326          "Maximum unroll factor for the unroll-and-jam transformation.",
1327          4, 0, 0)
1328
1329 DEFPARAM(PARAM_AVOID_FMA_MAX_BITS,
1330          "avoid-fma-max-bits",
1331          "Maximum number of bits for which we avoid creating FMAs.",
1332          0, 0, 512)
1333
1334 /*
1335
1336 Local variables:
1337 mode:c
1338 End:
1339 */