PR rtl-optimization/87817
[official-gcc.git] / gcc / params.def
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1 /* params.def - Run-time parameters.
2 Copyright (C) 2001-2018 Free Software Foundation, Inc.
3 Written by Mark Mitchell <mark@codesourcery.com>.
5 This file is part of GCC.
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.
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.
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/>. */
21 /* This file contains definitions for language-independent
22 parameters. The DEFPARAM macro takes 6 arguments:
24 - The enumeral corresponding to this parameter.
26 - The name that can be used to set this parameter using the
27 command-line option `--param <name>=<value>'.
29 - A help string explaining how the parameter is used.
31 - A default value for the parameter.
33 - The minimum acceptable value for the parameter.
35 - The maximum acceptable value for the parameter (if greater than
36 the minimum).
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.
43 Be sure to add an entry to invoke.texi summarizing the parameter. */
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
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)
216 /* Keep these up to date with those in configure.ac. */
217 DEFPARAM(PARAM_STACK_CLASH_PROTECTION_GUARD_SIZE,
218 "stack-clash-protection-guard-size",
219 "Size of the stack guard expressed as a power of two in bytes.",
220 12, 12, 30)
222 DEFPARAM(PARAM_STACK_CLASH_PROTECTION_PROBE_INTERVAL,
223 "stack-clash-protection-probe-interval",
224 "Interval in which to probe the stack expressed as a power of two in bytes.",
225 12, 10, 16)
227 /* The GCSE optimization will be disabled if it would require
228 significantly more memory than this value. */
229 DEFPARAM(PARAM_MAX_GCSE_MEMORY,
230 "max-gcse-memory",
231 "The maximum amount of memory to be allocated by GCSE.",
232 128 * 1024 * 1024, 0, 0)
234 /* The GCSE optimization of an expression will avoided if the ratio of
235 insertions to deletions is greater than this value. */
236 DEFPARAM(PARAM_MAX_GCSE_INSERTION_RATIO,
237 "max-gcse-insertion-ratio",
238 "The maximum ratio of insertions to deletions of expressions in GCSE.",
239 20, 0, 0)
241 /* This is the threshold ratio when to perform partial redundancy
242 elimination after reload. We perform partial redundancy elimination
243 when the following holds:
244 (Redundant load execution count)
245 ------------------------------- >= GCSE_AFTER_RELOAD_PARTIAL_FRACTION
246 (Added loads execution count) */
247 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_PARTIAL_FRACTION,
248 "gcse-after-reload-partial-fraction",
249 "The threshold ratio for performing partial redundancy elimination after reload.",
250 3, 0, 0)
251 /* This is the threshold ratio of the critical edges execution count compared to
252 the redundant loads execution count that permits performing the load
253 redundancy elimination in gcse after reload. */
254 DEFPARAM(PARAM_GCSE_AFTER_RELOAD_CRITICAL_FRACTION,
255 "gcse-after-reload-critical-fraction",
256 "The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload.",
257 10, 0, 0)
259 /* GCSE will use GCSE_COST_DISTANCE_RATION as a scaling factor
260 to calculate maximum distance for which an expression is allowed to move
261 from its rtx_cost. */
262 DEFPARAM(PARAM_GCSE_COST_DISTANCE_RATIO,
263 "gcse-cost-distance-ratio",
264 "Scaling factor in calculation of maximum distance an expression can be moved by GCSE optimizations.",
265 10, 0, 0)
266 /* GCSE won't restrict distance for which an expression with rtx_cost greater
267 than COSTS_N_INSN(GCSE_UNRESTRICTED_COST) is allowed to move. */
268 DEFPARAM(PARAM_GCSE_UNRESTRICTED_COST,
269 "gcse-unrestricted-cost",
270 "Cost at which GCSE optimizations will not constraint the distance an expression can travel.",
271 3, 0, 0)
273 /* How deep from a given basic block the dominator tree should be searched
274 for expressions to hoist to the block. The value of 0 will avoid limiting
275 the search. */
276 DEFPARAM(PARAM_MAX_HOIST_DEPTH,
277 "max-hoist-depth",
278 "Maximum depth of search in the dominator tree for expressions to hoist.",
279 30, 0, 0)
282 /* When synthesizing expnonentiation by a real constant operations using square
283 roots, this controls how deep sqrt chains we are willing to generate. */
284 DEFPARAM(PARAM_MAX_POW_SQRT_DEPTH,
285 "max-pow-sqrt-depth",
286 "Maximum depth of sqrt chains to use when synthesizing exponentiation by a real constant.",
287 5, 1, 32)
289 /* This parameter limits the number of insns in a loop that will be unrolled,
290 and by how much the loop is unrolled.
292 This limit should be at most half of the peeling limits: loop unroller
293 decides to not unroll loops that iterate fewer than 2*number of allowed
294 unrollings and thus we would have loops that are neither peeled or unrolled
295 otherwise. */
296 DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
297 "max-unrolled-insns",
298 "The maximum number of instructions to consider to unroll in a loop.",
299 200, 0, 0)
300 /* This parameter limits how many times the loop is unrolled depending
301 on number of insns really executed in each iteration. */
302 DEFPARAM(PARAM_MAX_AVERAGE_UNROLLED_INSNS,
303 "max-average-unrolled-insns",
304 "The maximum number of instructions to consider to unroll in a loop on average.",
305 80, 0, 0)
306 /* The maximum number of unrollings of a single loop. */
307 DEFPARAM(PARAM_MAX_UNROLL_TIMES,
308 "max-unroll-times",
309 "The maximum number of unrollings of a single loop.",
310 8, 0, 0)
311 /* The maximum number of insns of a peeled loop. */
312 DEFPARAM(PARAM_MAX_PEELED_INSNS,
313 "max-peeled-insns",
314 "The maximum number of insns of a peeled loop.",
315 100, 0, 0)
316 /* The maximum number of peelings of a single loop. */
317 DEFPARAM(PARAM_MAX_PEEL_TIMES,
318 "max-peel-times",
319 "The maximum number of peelings of a single loop.",
320 16, 0, 0)
321 /* The maximum number of peelings of a single loop that is peeled completely. */
322 DEFPARAM(PARAM_MAX_PEEL_BRANCHES,
323 "max-peel-branches",
324 "The maximum number of branches on the path through the peeled sequence.",
325 32, 0, 0)
326 /* The maximum number of insns of a peeled loop. */
327 DEFPARAM(PARAM_MAX_COMPLETELY_PEELED_INSNS,
328 "max-completely-peeled-insns",
329 "The maximum number of insns of a completely peeled loop.",
330 200, 0, 0)
331 /* The maximum number of peelings of a single loop that is peeled completely. */
332 DEFPARAM(PARAM_MAX_COMPLETELY_PEEL_TIMES,
333 "max-completely-peel-times",
334 "The maximum number of peelings of a single loop that is peeled completely.",
335 16, 0, 0)
336 /* The maximum number of insns of a peeled loop that rolls only once. */
337 DEFPARAM(PARAM_MAX_ONCE_PEELED_INSNS,
338 "max-once-peeled-insns",
339 "The maximum number of insns of a peeled loop that rolls only once.",
340 400, 0, 0)
341 /* The maximum depth of a loop nest we completely peel. */
342 DEFPARAM(PARAM_MAX_UNROLL_ITERATIONS,
343 "max-completely-peel-loop-nest-depth",
344 "The maximum depth of a loop nest we completely peel.",
345 8, 0, 0)
347 /* The maximum number of insns of an unswitched loop. */
348 DEFPARAM(PARAM_MAX_UNSWITCH_INSNS,
349 "max-unswitch-insns",
350 "The maximum number of insns of an unswitched loop.",
351 50, 0, 0)
352 /* The maximum level of recursion in unswitch_single_loop. */
353 DEFPARAM(PARAM_MAX_UNSWITCH_LEVEL,
354 "max-unswitch-level",
355 "The maximum number of unswitchings in a single loop.",
356 3, 0, 0)
358 /* The maximum number of insns in loop header duplicated by the copy loop
359 headers pass. */
360 DEFPARAM(PARAM_MAX_LOOP_HEADER_INSNS,
361 "max-loop-header-insns",
362 "The maximum number of insns in loop header duplicated by the copy loop headers pass.",
363 20, 0, 0)
365 /* The maximum number of iterations of a loop the brute force algorithm
366 for analysis of # of iterations of the loop tries to evaluate. */
367 DEFPARAM(PARAM_MAX_ITERATIONS_TO_TRACK,
368 "max-iterations-to-track",
369 "Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates.",
370 1000, 0, 0)
371 /* A cutoff to avoid costly computations of the number of iterations in
372 the doloop transformation. */
373 DEFPARAM(PARAM_MAX_ITERATIONS_COMPUTATION_COST,
374 "max-iterations-computation-cost",
375 "Bound on the cost of an expression to compute the number of iterations.",
376 10, 0, 0)
378 /* This parameter is used to tune SMS MAX II calculations. */
379 DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
380 "sms-max-ii-factor",
381 "A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop.",
382 100, 0, 0)
383 /* The minimum value of stage count that swing modulo scheduler will generate. */
384 DEFPARAM(PARAM_SMS_MIN_SC,
385 "sms-min-sc",
386 "The minimum value of stage count that swing modulo scheduler will generate.",
387 2, 1, 1)
388 DEFPARAM(PARAM_SMS_DFA_HISTORY,
389 "sms-dfa-history",
390 "The number of cycles the swing modulo scheduler considers when checking conflicts using DFA.",
391 0, 0, 0)
392 DEFPARAM(PARAM_SMS_LOOP_AVERAGE_COUNT_THRESHOLD,
393 "sms-loop-average-count-threshold",
394 "A threshold on the average loop count considered by the swing modulo scheduler.",
395 0, 0, 0)
397 DEFPARAM(HOT_BB_COUNT_FRACTION,
398 "hot-bb-count-fraction",
399 "Select fraction of the maximal count of repetitions of basic block in program given basic "
400 "block needs to have to be considered hot (used in non-LTO mode)",
401 10000, 0, 0)
402 DEFPARAM(HOT_BB_COUNT_WS_PERMILLE,
403 "hot-bb-count-ws-permille",
404 "A basic block profile count is considered hot if it contributes to "
405 "the given permillage of the entire profiled execution (used in LTO mode).",
406 999, 0, 1000)
407 DEFPARAM(HOT_BB_FREQUENCY_FRACTION,
408 "hot-bb-frequency-fraction",
409 "Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot.",
410 1000, 0, 0)
412 DEFPARAM(UNLIKELY_BB_COUNT_FRACTION,
413 "unlikely-bb-count-fraction",
414 "The minimum fraction of profile runs a given basic block execution count must be not to be considered unlikely.",
415 20, 1, 10000)
417 DEFPARAM (PARAM_ALIGN_THRESHOLD,
418 "align-threshold",
419 "Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment.",
420 100, 1, 0)
422 DEFPARAM (PARAM_ALIGN_LOOP_ITERATIONS,
423 "align-loop-iterations",
424 "Loops iterating at least selected number of iterations will get "
425 "loop alignment.", 4, 0, 0)
427 /* For guessed profiles, the loops having unknown number of iterations
428 are predicted to iterate relatively few (10) times at average.
429 For functions containing one loop with large known number of iterations
430 and other loops having unbounded loops we would end up predicting all
431 the other loops cold that is not usually the case. So we need to artificially
432 flatten the profile.
434 We need to cut the maximal predicted iterations to large enough iterations
435 so the loop appears important, but safely within maximum hotness
436 range. */
438 DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
439 "max-predicted-iterations",
440 "The maximum number of loop iterations we predict statically.",
441 100, 0, 0)
443 /* This parameter controls the probability of builtin_expect. The default
444 value is 90%. This empirical value is obtained through the weighted
445 probability of FDO counters (with the FDO count value as the weight)
446 in some real world programs:
447 (1) Google performance test benchmarks: the probability is 0.9081.
448 (2) Linux 3.3 kernel running Google search workload: the probability
449 is 0.8717. */
451 DEFPARAM(BUILTIN_EXPECT_PROBABILITY,
452 "builtin-expect-probability",
453 "Set the estimated probability in percentage for builtin expect. The default value is 90% probability.",
454 90, 0, 100)
455 DEFPARAM(BUILTIN_STRING_CMP_INLINE_LENGTH,
456 "builtin-string-cmp-inline-length",
457 "The maximum length of a constant string for a builtin string cmp call eligible for inlining. The default value is 3.",
458 3, 0, 100)
459 DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK,
460 "tracer-dynamic-coverage-feedback",
461 "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available.",
462 95, 0, 100)
463 DEFPARAM(TRACER_DYNAMIC_COVERAGE,
464 "tracer-dynamic-coverage",
465 "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available.",
466 75, 0, 100)
467 DEFPARAM(TRACER_MAX_CODE_GROWTH,
468 "tracer-max-code-growth",
469 "Maximal code growth caused by tail duplication (in percent).",
470 100, 0, 0)
471 DEFPARAM(TRACER_MIN_BRANCH_RATIO,
472 "tracer-min-branch-ratio",
473 "Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent).",
474 10, 0, 100)
475 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK,
476 "tracer-min-branch-probability-feedback",
477 "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available.",
478 80, 0, 100)
479 DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY,
480 "tracer-min-branch-probability",
481 "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available.",
482 50, 0, 100)
484 /* The maximum number of incoming edges to consider for crossjumping. */
485 DEFPARAM(PARAM_MAX_CROSSJUMP_EDGES,
486 "max-crossjump-edges",
487 "The maximum number of incoming edges to consider for crossjumping.",
488 100, 0, 0)
490 /* The minimum number of matching instructions to consider for crossjumping. */
491 DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
492 "min-crossjump-insns",
493 "The minimum number of matching instructions to consider for crossjumping.",
494 5, 1, 0)
496 /* The maximum number expansion factor when copying basic blocks. */
497 DEFPARAM(PARAM_MAX_GROW_COPY_BB_INSNS,
498 "max-grow-copy-bb-insns",
499 "The maximum expansion factor when copying basic blocks.",
500 8, 0, 0)
502 /* The maximum number of insns to duplicate when unfactoring computed gotos. */
503 DEFPARAM(PARAM_MAX_GOTO_DUPLICATION_INSNS,
504 "max-goto-duplication-insns",
505 "The maximum number of insns to duplicate when unfactoring computed gotos.",
506 8, 0, 0)
508 /* The maximum length of path considered in cse. */
509 DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
510 "max-cse-path-length",
511 "The maximum length of path considered in cse.",
512 10, 1, 0)
513 DEFPARAM(PARAM_MAX_CSE_INSNS,
514 "max-cse-insns",
515 "The maximum instructions CSE process before flushing.",
516 1000, 0, 0)
518 /* The cost of expression in loop invariant motion that is considered
519 expensive. */
520 DEFPARAM(PARAM_LIM_EXPENSIVE,
521 "lim-expensive",
522 "The minimum cost of an expensive expression in the loop invariant motion.",
523 20, 0, 0)
525 /* Bound on number of candidates for induction variables below that
526 all candidates are considered for each use in induction variable
527 optimizations. */
529 DEFPARAM(PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND,
530 "iv-consider-all-candidates-bound",
531 "Bound on number of candidates below that all candidates are considered in iv optimizations.",
532 40, 0, 0)
534 /* The induction variable optimizations give up on loops that contain more
535 induction variable uses. */
537 DEFPARAM(PARAM_IV_MAX_CONSIDERED_USES,
538 "iv-max-considered-uses",
539 "Bound on number of iv uses in loop optimized in iv optimizations.",
540 250, 0, 0)
542 /* If there are at most this number of ivs in the set, try removing unnecessary
543 ivs from the set always. */
545 DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
546 "iv-always-prune-cand-set-bound",
547 "If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization.",
548 10, 0, 0)
550 DEFPARAM(PARAM_AVG_LOOP_NITER,
551 "avg-loop-niter",
552 "Average number of iterations of a loop.",
553 10, 1, 0)
555 DEFPARAM(PARAM_DSE_MAX_OBJECT_SIZE,
556 "dse-max-object-size",
557 "Maximum size (in bytes) of objects tracked bytewise by dead store elimination.",
558 256, 0, 0)
560 DEFPARAM(PARAM_DSE_MAX_ALIAS_QUERIES_PER_STORE,
561 "dse-max-alias-queries-per-store",
562 "Maximum number of queries into the alias oracle per store.",
563 256, 0, 0)
565 DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
566 "scev-max-expr-size",
567 "Bound on size of expressions used in the scalar evolutions analyzer.",
568 100, 0, 0)
570 DEFPARAM(PARAM_SCEV_MAX_EXPR_COMPLEXITY,
571 "scev-max-expr-complexity",
572 "Bound on the complexity of the expressions in the scalar evolutions analyzer.",
573 10, 0, 0)
575 DEFPARAM (PARAM_MAX_TREE_IF_CONVERSION_PHI_ARGS,
576 "max-tree-if-conversion-phi-args",
577 "Maximum number of arguments in a PHI supported by TREE if-conversion "
578 "unless the loop is marked with simd pragma.",
579 4, 2, 0)
581 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS,
582 "vect-max-version-for-alignment-checks",
583 "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check.",
584 6, 0, 0)
586 DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS,
587 "vect-max-version-for-alias-checks",
588 "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check.",
589 10, 0, 0)
591 DEFPARAM(PARAM_VECT_MAX_PEELING_FOR_ALIGNMENT,
592 "vect-max-peeling-for-alignment",
593 "Maximum number of loop peels to enhance alignment of data references in a loop.",
594 -1, -1, 64)
596 DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
597 "max-cselib-memory-locations",
598 "The maximum memory locations recorded by cselib.",
599 500, 0, 0)
601 #ifdef ENABLE_GC_ALWAYS_COLLECT
602 # define GGC_MIN_EXPAND_DEFAULT 0
603 # define GGC_MIN_HEAPSIZE_DEFAULT 0
604 #else
605 # define GGC_MIN_EXPAND_DEFAULT 30
606 # define GGC_MIN_HEAPSIZE_DEFAULT 4096
607 #endif
609 DEFPARAM(GGC_MIN_EXPAND,
610 "ggc-min-expand",
611 "Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap.",
612 GGC_MIN_EXPAND_DEFAULT, 0, 0)
614 DEFPARAM(GGC_MIN_HEAPSIZE,
615 "ggc-min-heapsize",
616 "Minimum heap size before we start collecting garbage, in kilobytes.",
617 GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
619 #undef GGC_MIN_EXPAND_DEFAULT
620 #undef GGC_MIN_HEAPSIZE_DEFAULT
622 DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
623 "max-reload-search-insns",
624 "The maximum number of instructions to search backward when looking for equivalent reload.",
625 100, 0, 0)
627 DEFPARAM(PARAM_SINK_FREQUENCY_THRESHOLD,
628 "sink-frequency-threshold",
629 "Target block's relative execution frequency (as a percentage) required to sink a statement.",
630 75, 0, 100)
632 DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
633 "max-sched-region-blocks",
634 "The maximum number of blocks in a region to be considered for interblock scheduling.",
635 10, 0, 0)
637 DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
638 "max-sched-region-insns",
639 "The maximum number of insns in a region to be considered for interblock scheduling.",
640 100, 0, 0)
642 DEFPARAM(PARAM_MAX_PIPELINE_REGION_BLOCKS,
643 "max-pipeline-region-blocks",
644 "The maximum number of blocks in a region to be considered for interblock scheduling.",
645 15, 0, 0)
647 DEFPARAM(PARAM_MAX_PIPELINE_REGION_INSNS,
648 "max-pipeline-region-insns",
649 "The maximum number of insns in a region to be considered for interblock scheduling.",
650 200, 0, 0)
652 DEFPARAM(PARAM_MIN_SPEC_PROB,
653 "min-spec-prob",
654 "The minimum probability of reaching a source block for interblock speculative scheduling.",
655 40, 0, 0)
657 DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
658 "max-sched-extend-regions-iters",
659 "The maximum number of iterations through CFG to extend regions.",
660 0, 0, 0)
662 DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
663 "max-sched-insn-conflict-delay",
664 "The maximum conflict delay for an insn to be considered for speculative motion.",
665 3, 1, 10)
667 DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
668 "sched-spec-prob-cutoff",
669 "The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
670 40, 0, 100)
672 DEFPARAM(PARAM_SCHED_STATE_EDGE_PROB_CUTOFF,
673 "sched-state-edge-prob-cutoff",
674 "The minimum probability an edge must have for the scheduler to save its state across it.",
675 10, 0, 100)
677 DEFPARAM(PARAM_SELSCHED_MAX_LOOKAHEAD,
678 "selsched-max-lookahead",
679 "The maximum size of the lookahead window of selective scheduling.",
680 50, 0, 0)
682 DEFPARAM(PARAM_SELSCHED_MAX_SCHED_TIMES,
683 "selsched-max-sched-times",
684 "Maximum number of times that an insn could be scheduled.",
685 2, 1, 0)
687 DEFPARAM(PARAM_SELSCHED_INSNS_TO_RENAME,
688 "selsched-insns-to-rename",
689 "Maximum number of instructions in the ready list that are considered eligible for renaming.",
690 2, 0, 0)
692 DEFPARAM (PARAM_SCHED_MEM_TRUE_DEP_COST,
693 "sched-mem-true-dep-cost",
694 "Minimal distance between possibly conflicting store and load.",
695 1, 0, 0)
697 DEFPARAM (PARAM_SCHED_AUTOPREF_QUEUE_DEPTH,
698 "sched-autopref-queue-depth",
699 "Hardware autoprefetcher scheduler model control flag. Number of lookahead cycles the model looks into; at '0' only enable instruction sorting heuristic. Disabled by default.",
700 -1, 0, 0)
702 DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
703 "max-last-value-rtl",
704 "The maximum number of RTL nodes that can be recorded as combiner's last value.",
705 10000, 0, 0)
707 DEFPARAM(PARAM_MAX_COMBINE_INSNS,
708 "max-combine-insns",
709 "The maximum number of insns combine tries to combine.",
710 4, 2, 4)
712 /* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
713 {signed,unsigned} integral types. This determines N.
714 Experimentation shows 251 to be a good value that generates the
715 least amount of garbage for allocating the TREE_VEC storage. */
716 DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
717 "integer-share-limit",
718 "The upper bound for sharing integer constants.",
719 251, 2, 2)
721 DEFPARAM (PARAM_SSP_BUFFER_SIZE,
722 "ssp-buffer-size",
723 "The lower bound for a buffer to be considered for stack smashing protection.",
724 8, 1, 0)
726 DEFPARAM (PARAM_MIN_SIZE_FOR_STACK_SHARING,
727 "min-size-for-stack-sharing",
728 "The minimum size of variables taking part in stack slot sharing "
729 "when not optimizing.",
730 32, 0, 0)
732 /* When we thread through a block we have to make copies of the
733 statements within the block. Clearly for large blocks the code
734 duplication is bad.
736 PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
737 of statements and PHI nodes allowed in a block which is going to
738 be duplicated for thread jumping purposes.
740 Some simple analysis showed that more than 99% of the jump
741 threading opportunities are for blocks with less than 15
742 statements. So we can get the benefits of jump threading
743 without excessive code bloat for pathological cases with the
744 throttle set at 15 statements. */
745 DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
746 "max-jump-thread-duplication-stmts",
747 "Maximum number of statements allowed in a block that needs to be duplicated when threading jumps.",
748 15, 0, 0)
750 /* This is the maximum number of fields a variable may have before the pointer analysis machinery
751 will stop trying to treat it in a field-sensitive manner.
752 There are programs out there with thousands of fields per structure, and handling them
753 field-sensitively is not worth the cost. */
754 DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
755 "max-fields-for-field-sensitive",
756 "Maximum number of fields in a structure before pointer analysis treats the structure as a single variable.",
757 0, 0, 0)
759 DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
760 "max-sched-ready-insns",
761 "The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass.",
762 100, 1, 0)
764 /* This is the maximum number of active local stores RTL DSE will consider. */
765 DEFPARAM (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES,
766 "max-dse-active-local-stores",
767 "Maximum number of active local stores in RTL dead store elimination.",
768 5000, 0, 0)
770 /* Prefetching and cache-optimizations related parameters. Default values are
771 usually set by machine description. */
773 /* The number of insns executed before prefetch is completed. */
775 DEFPARAM (PARAM_PREFETCH_LATENCY,
776 "prefetch-latency",
777 "The number of insns executed before prefetch is completed.",
778 200, 0, 0)
780 /* The number of prefetches that can run at the same time. */
782 DEFPARAM (PARAM_SIMULTANEOUS_PREFETCHES,
783 "simultaneous-prefetches",
784 "The number of prefetches that can run at the same time.",
785 3, 0, 0)
787 /* The size of L1 cache in kB. */
789 DEFPARAM (PARAM_L1_CACHE_SIZE,
790 "l1-cache-size",
791 "The size of L1 cache.",
792 64, 0, 0)
794 /* The size of L1 cache line in bytes. */
796 DEFPARAM (PARAM_L1_CACHE_LINE_SIZE,
797 "l1-cache-line-size",
798 "The size of L1 cache line.",
799 32, 0, 0)
801 /* The size of L2 cache in kB. */
803 DEFPARAM (PARAM_L2_CACHE_SIZE,
804 "l2-cache-size",
805 "The size of L2 cache.",
806 512, 0, 0)
808 /* Whether software prefetch hints should be issued for non-constant
809 strides. */
811 DEFPARAM (PARAM_PREFETCH_DYNAMIC_STRIDES,
812 "prefetch-dynamic-strides",
813 "Whether software prefetch hints should be issued for non-constant "
814 "strides.",
815 1, 0, 1)
817 /* The minimum constant stride beyond which we should use prefetch hints
818 for. */
820 DEFPARAM (PARAM_PREFETCH_MINIMUM_STRIDE,
821 "prefetch-minimum-stride",
822 "The minimum constant stride beyond which we should use prefetch "
823 "hints for.",
824 -1, 0, 0)
826 /* Maximum number of statements in loop nest for loop interchange. */
828 DEFPARAM (PARAM_LOOP_INTERCHANGE_MAX_NUM_STMTS,
829 "loop-interchange-max-num-stmts",
830 "The maximum number of stmts in loop nest for loop interchange.",
831 64, 0, 0)
833 /* Minimum stride ratio for loop interchange to be profitiable. */
835 DEFPARAM (PARAM_LOOP_INTERCHANGE_STRIDE_RATIO,
836 "loop-interchange-stride-ratio",
837 "The minimum stride ratio for loop interchange to be profitable.",
838 2, 0, 0)
840 /* Whether we should use canonical types rather than deep "structural"
841 type checking. Setting this value to 1 (the default) improves
842 compilation performance in the C++ and Objective-C++ front end;
843 this value should only be set to zero to work around bugs in the
844 canonical type system by disabling it. */
846 DEFPARAM (PARAM_USE_CANONICAL_TYPES,
847 "use-canonical-types",
848 "Whether to use canonical types.",
849 1, 0, 1)
851 DEFPARAM (PARAM_MAX_PARTIAL_ANTIC_LENGTH,
852 "max-partial-antic-length",
853 "Maximum length of partial antic set when performing tree pre optimization.",
854 100, 0, 0)
856 /* The following is used as a stop-gap limit for cases where really deep
857 loop nests cause compile-time to blow up. If we hit this limit,
858 FRE and PRE will value-number outer loops (but the outermost) in a
859 loop nest non-optimistically. */
861 DEFPARAM (PARAM_RPO_VN_MAX_LOOP_DEPTH,
862 "rpo-vn-max-loop-depth",
863 "Maximum depth of a loop nest to fully value-number optimistically.",
864 7, 2, 0)
866 /* The following is used as a stop-gap limit for cases where really huge
867 functions blow up compile-time use too much. It limits the number of
868 alias-queries we do for finding common subexpressions for memory loads and
869 stores. The number of alias-queries is otherwise limited by the number of
870 stores on paths to function entry. */
872 DEFPARAM (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS,
873 "sccvn-max-alias-queries-per-access",
874 "Maximum number of disambiguations to perform per memory access.",
875 1000, 0, 0)
877 DEFPARAM (PARAM_IRA_MAX_LOOPS_NUM,
878 "ira-max-loops-num",
879 "Max loops number for regional RA.",
880 100, 0, 0)
882 DEFPARAM (PARAM_IRA_MAX_CONFLICT_TABLE_SIZE,
883 "ira-max-conflict-table-size",
884 "Max size of conflict table in MB.",
885 1000, 0, 0)
887 DEFPARAM (PARAM_IRA_LOOP_RESERVED_REGS,
888 "ira-loop-reserved-regs",
889 "The number of registers in each class kept unused by loop invariant motion.",
890 2, 0, 0)
892 DEFPARAM (PARAM_LRA_MAX_CONSIDERED_RELOAD_PSEUDOS,
893 "lra-max-considered-reload-pseudos",
894 "The max number of reload pseudos which are considered during spilling a non-reload pseudo.",
895 500, 0, 0)
897 DEFPARAM (PARAM_LRA_INHERITANCE_EBB_PROBABILITY_CUTOFF,
898 "lra-inheritance-ebb-probability-cutoff",
899 "Minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA.",
900 40, 0, 100)
902 /* Switch initialization conversion will refuse to create arrays that are
903 bigger than this parameter times the number of switch branches. */
905 DEFPARAM (PARAM_SWITCH_CONVERSION_BRANCH_RATIO,
906 "switch-conversion-max-branch-ratio",
907 "The maximum ratio between array size and switch branches for "
908 "a switch conversion to take place.",
909 8, 1, 0)
911 /* Size of tiles when doing loop blocking. */
913 DEFPARAM (PARAM_LOOP_BLOCK_TILE_SIZE,
914 "loop-block-tile-size",
915 "Size of tiles for loop blocking.",
916 51, 0, 0)
918 /* Maximal number of parameters that we allow in a SCoP. */
920 DEFPARAM (PARAM_GRAPHITE_MAX_NB_SCOP_PARAMS,
921 "graphite-max-nb-scop-params",
922 "Maximum number of parameters in a SCoP.",
923 10, 0, 0)
925 /* Maximal number of array references in a scop. */
927 DEFPARAM (PARAM_GRAPHITE_MAX_ARRAYS_PER_SCOP,
928 "graphite-max-arrays-per-scop",
929 "Maximum number of arrays per scop.",
930 100, 0, 0)
932 DEFPARAM (PARAM_MAX_ISL_OPERATIONS,
933 "max-isl-operations",
934 "Maximum number of isl operations, 0 means unlimited.",
935 350000, 0, 0)
937 /* For testsuite purposes allow to check for codegen error handling. */
938 DEFPARAM (PARAM_GRAPHITE_ALLOW_CODEGEN_ERRORS,
939 "graphite-allow-codegen-errors",
940 "Whether codegen errors should be ICEs when -fchecking.",
941 0, 0, 1)
943 /* Avoid data dependence analysis on very large loops. */
944 DEFPARAM (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS,
945 "loop-max-datarefs-for-datadeps",
946 "Maximum number of datarefs in loop for building loop data dependencies.",
947 1000, 0, 0)
949 /* Avoid doing loop invariant motion on very large loops. */
951 DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_IN_LOOP,
952 "loop-invariant-max-bbs-in-loop",
953 "Max basic blocks number in loop for loop invariant motion.",
954 10000, 0, 0)
956 /* When the parameter is 1, use the internal function id
957 to look up for profile data. Otherwise, use a more stable
958 external id based on assembler name and source location. */
959 DEFPARAM (PARAM_PROFILE_FUNC_INTERNAL_ID,
960 "profile-func-internal-id",
961 "Use internal function id in profile lookup.",
962 0, 0, 1)
964 /* When the parameter is 1, track the most frequent N target
965 addresses in indirect-call profile. This disables
966 indirect_call_profiler_v2 which tracks single target. */
967 DEFPARAM (PARAM_INDIR_CALL_TOPN_PROFILE,
968 "indir-call-topn-profile",
969 "Track top N target addresses in indirect-call profile.",
970 0, 0, 1)
972 /* Avoid SLP vectorization of large basic blocks. */
973 DEFPARAM (PARAM_SLP_MAX_INSNS_IN_BB,
974 "slp-max-insns-in-bb",
975 "Maximum number of instructions in basic block to be considered for "
976 "SLP vectorization.", 1000, 0, 0)
978 DEFPARAM (PARAM_MIN_INSN_TO_PREFETCH_RATIO,
979 "min-insn-to-prefetch-ratio",
980 "Min. ratio of insns to prefetches to enable prefetching for "
981 "a loop with an unknown trip count.",
982 9, 0, 0)
984 DEFPARAM (PARAM_PREFETCH_MIN_INSN_TO_MEM_RATIO,
985 "prefetch-min-insn-to-mem-ratio",
986 "Min. ratio of insns to mem ops to enable prefetching in a loop.",
987 3, 0, 0)
989 /* Set maximum hash table size for var tracking. */
991 DEFPARAM (PARAM_MAX_VARTRACK_SIZE,
992 "max-vartrack-size",
993 "Max. size of var tracking hash tables.",
994 50000000, 0, 0)
996 /* Set maximum recursion depth for var tracking expression expansion
997 and resolution. */
999 DEFPARAM (PARAM_MAX_VARTRACK_EXPR_DEPTH,
1000 "max-vartrack-expr-depth",
1001 "Max. recursion depth for expanding var tracking expressions.",
1002 12, 0, 0)
1004 /* Set maximum length of value location list for which var tracking
1005 should add reverse operations. */
1007 DEFPARAM (PARAM_MAX_VARTRACK_REVERSE_OP_SIZE,
1008 "max-vartrack-reverse-op-size",
1009 "Max. size of loc list for which reverse ops should be added.",
1010 50, 0, 0)
1012 /* Set a threshold to discard debug markers (e.g. debug begin stmt
1013 markers) when expanding a function to RTL, or inlining it into
1014 another function. */
1016 DEFPARAM (PARAM_MAX_DEBUG_MARKER_COUNT,
1017 "max-debug-marker-count",
1018 "Max. count of debug markers to expand or inline.",
1019 100000, 0, 0)
1021 /* Set minimum insn uid for non-debug insns. */
1023 DEFPARAM (PARAM_MIN_NONDEBUG_INSN_UID,
1024 "min-nondebug-insn-uid",
1025 "The minimum UID to be used for a nondebug insn.",
1026 0, 0, 0)
1028 DEFPARAM (PARAM_IPA_SRA_PTR_GROWTH_FACTOR,
1029 "ipa-sra-ptr-growth-factor",
1030 "Maximum allowed growth of number and total size of new parameters "
1031 "that ipa-sra replaces a pointer to an aggregate with.",
1032 2, 0, 0)
1034 DEFPARAM (PARAM_TM_MAX_AGGREGATE_SIZE,
1035 "tm-max-aggregate-size",
1036 "Size in bytes after which thread-local aggregates should be "
1037 "instrumented with the logging functions instead of save/restore "
1038 "pairs.",
1039 9, 0, 0)
1041 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SPEED,
1042 "sra-max-scalarization-size-Ospeed",
1043 "Maximum size, in storage units, of an aggregate which should be "
1044 "considered for scalarization when compiling for speed.",
1045 0, 0, 0)
1047 DEFPARAM (PARAM_SRA_MAX_SCALARIZATION_SIZE_SIZE,
1048 "sra-max-scalarization-size-Osize",
1049 "Maximum size, in storage units, of an aggregate which should be "
1050 "considered for scalarization when compiling for size.",
1051 0, 0, 0)
1053 DEFPARAM (PARAM_IPA_CP_VALUE_LIST_SIZE,
1054 "ipa-cp-value-list-size",
1055 "Maximum size of a list of values associated with each parameter for "
1056 "interprocedural constant propagation.",
1057 8, 0, 0)
1059 DEFPARAM (PARAM_IPA_CP_EVAL_THRESHOLD,
1060 "ipa-cp-eval-threshold",
1061 "Threshold ipa-cp opportunity evaluation that is still considered "
1062 "beneficial to clone.",
1063 500, 0, 0)
1065 DEFPARAM (PARAM_IPA_CP_RECURSION_PENALTY,
1066 "ipa-cp-recursion-penalty",
1067 "Percentage penalty the recursive functions will receive when they "
1068 "are evaluated for cloning.",
1069 40, 0, 100)
1071 DEFPARAM (PARAM_IPA_CP_SINGLE_CALL_PENALTY,
1072 "ipa-cp-single-call-penalty",
1073 "Percentage penalty functions containing a single call to another "
1074 "function will receive when they are evaluated for cloning.",
1075 15, 0, 100)
1077 DEFPARAM (PARAM_IPA_MAX_AGG_ITEMS,
1078 "ipa-max-agg-items",
1079 "Maximum number of aggregate content items for a parameter in "
1080 "jump functions and lattices.",
1081 16, 0, 0)
1083 DEFPARAM (PARAM_IPA_CP_LOOP_HINT_BONUS,
1084 "ipa-cp-loop-hint-bonus",
1085 "Compile-time bonus IPA-CP assigns to candidates which make loop "
1086 "bounds or strides known.",
1087 64, 0, 0)
1089 DEFPARAM (PARAM_IPA_CP_ARRAY_INDEX_HINT_BONUS,
1090 "ipa-cp-array-index-hint-bonus",
1091 "Compile-time bonus IPA-CP assigns to candidates which make an array "
1092 "index known.",
1093 48, 0, 0)
1095 DEFPARAM (PARAM_IPA_MAX_AA_STEPS,
1096 "ipa-max-aa-steps",
1097 "Maximum number of statements that will be visited by IPA formal "
1098 "parameter analysis based on alias analysis in any given function.",
1099 25000, 0, 0)
1101 /* WHOPR partitioning configuration. */
1103 DEFPARAM (PARAM_LTO_PARTITIONS,
1104 "lto-partitions",
1105 "Number of partitions the program should be split to.",
1106 128, 1, 0)
1108 DEFPARAM (MIN_PARTITION_SIZE,
1109 "lto-min-partition",
1110 "Minimal size of a partition for LTO (in estimated instructions).",
1111 10000, 0, 0)
1113 DEFPARAM (MAX_PARTITION_SIZE,
1114 "lto-max-partition",
1115 "Maximal size of a partition for LTO (in estimated instructions).",
1116 1000000, 0, INT_MAX)
1118 /* Diagnostic parameters. */
1120 DEFPARAM (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP,
1121 "cxx-max-namespaces-for-diagnostic-help",
1122 "Maximum number of namespaces to search for alternatives when "
1123 "name lookup fails.",
1124 1000, 0, 0)
1126 /* Maximum number of conditional store pairs that can be sunk. */
1127 DEFPARAM (PARAM_MAX_STORES_TO_SINK,
1128 "max-stores-to-sink",
1129 "Maximum number of conditional store pairs that can be sunk.",
1130 2, 0, 0)
1132 /* Override CASE_VALUES_THRESHOLD of when to switch from doing switch
1133 statements via if statements to using a table jump operation. If the value
1134 is 0, the default CASE_VALUES_THRESHOLD will be used. */
1135 DEFPARAM (PARAM_CASE_VALUES_THRESHOLD,
1136 "case-values-threshold",
1137 "The smallest number of different values for which it is best to "
1138 "use a jump-table instead of a tree of conditional branches, "
1139 "if 0, use the default for the machine.",
1140 0, 0, 0)
1142 /* Data race flags for C++0x memory model compliance. */
1143 DEFPARAM (PARAM_ALLOW_STORE_DATA_RACES,
1144 "allow-store-data-races",
1145 "Allow new data races on stores to be introduced.",
1146 0, 0, 1)
1148 /* Reassociation width to be used by tree reassoc optimization. */
1149 DEFPARAM (PARAM_TREE_REASSOC_WIDTH,
1150 "tree-reassoc-width",
1151 "Set the maximum number of instructions executed in parallel in "
1152 "reassociated tree. If 0, use the target dependent heuristic.",
1153 0, 0, 0)
1155 DEFPARAM (PARAM_MAX_TAIL_MERGE_COMPARISONS,
1156 "max-tail-merge-comparisons",
1157 "Maximum amount of similar bbs to compare a bb with.",
1158 10, 0, 0)
1160 DEFPARAM (PARAM_STORE_MERGING_ALLOW_UNALIGNED,
1161 "store-merging-allow-unaligned",
1162 "Allow the store merging pass to introduce unaligned stores "
1163 "if it is legal to do so.",
1164 1, 0, 1)
1166 DEFPARAM (PARAM_MAX_STORES_TO_MERGE,
1167 "max-stores-to-merge",
1168 "Maximum number of constant stores to merge in the "
1169 "store merging pass.",
1170 64, 2, 0)
1172 DEFPARAM (PARAM_MAX_TAIL_MERGE_ITERATIONS,
1173 "max-tail-merge-iterations",
1174 "Maximum amount of iterations of the pass over a function.",
1175 2, 0, 0)
1177 /* Maximum number of strings for which strlen optimization pass will
1178 track string lenths. */
1179 DEFPARAM (PARAM_MAX_TRACKED_STRLENS,
1180 "max-tracked-strlens",
1181 "Maximum number of strings for which strlen optimization pass will "
1182 "track string lengths.",
1183 10000, 0, 0)
1185 /* Keep this in sync with the sched_pressure_algorithm enum. */
1186 DEFPARAM (PARAM_SCHED_PRESSURE_ALGORITHM,
1187 "sched-pressure-algorithm",
1188 "Which -fsched-pressure algorithm to apply.",
1189 1, 1, 2)
1191 /* Maximum length of candidate scans in straight-line strength reduction. */
1192 DEFPARAM (PARAM_MAX_SLSR_CANDIDATE_SCAN,
1193 "max-slsr-cand-scan",
1194 "Maximum length of candidate scans for straight-line "
1195 "strength reduction.",
1196 50, 1, 999999)
1198 /* ASan stands for AddressSanitizer: https://github.com/google/sanitizers. */
1200 DEFPARAM (PARAM_ASAN_STACK,
1201 "asan-stack",
1202 "Enable asan stack protection.",
1203 1, 0, 1)
1205 DEFPARAM (PARAM_ASAN_PROTECT_ALLOCAS,
1206 "asan-instrument-allocas",
1207 "Enable asan allocas/VLAs protection.",
1208 1, 0, 1)
1210 DEFPARAM (PARAM_ASAN_GLOBALS,
1211 "asan-globals",
1212 "Enable asan globals protection.",
1213 1, 0, 1)
1215 DEFPARAM (PARAM_ASAN_INSTRUMENT_WRITES,
1216 "asan-instrument-writes",
1217 "Enable asan store operations protection.",
1218 1, 0, 1)
1220 DEFPARAM (PARAM_ASAN_INSTRUMENT_READS,
1221 "asan-instrument-reads",
1222 "Enable asan load operations protection.",
1223 1, 0, 1)
1225 DEFPARAM (PARAM_ASAN_MEMINTRIN,
1226 "asan-memintrin",
1227 "Enable asan builtin functions protection.",
1228 1, 0, 1)
1230 DEFPARAM (PARAM_ASAN_USE_AFTER_RETURN,
1231 "asan-use-after-return",
1232 "Enable asan detection of use-after-return bugs.",
1233 1, 0, 1)
1235 DEFPARAM (PARAM_ASAN_INSTRUMENTATION_WITH_CALL_THRESHOLD,
1236 "asan-instrumentation-with-call-threshold",
1237 "Use callbacks instead of inline code if number of accesses "
1238 "in function becomes greater or equal to this number.",
1239 7000, 0, INT_MAX)
1241 DEFPARAM (PARAM_USE_AFTER_SCOPE_DIRECT_EMISSION_THRESHOLD,
1242 "use-after-scope-direct-emission-threshold",
1243 "Use direct poisoning/unpoisoning instructions for variables "
1244 "smaller or equal to this number.",
1245 256, 0, INT_MAX)
1247 DEFPARAM (PARAM_UNINIT_CONTROL_DEP_ATTEMPTS,
1248 "uninit-control-dep-attempts",
1249 "Maximum number of nested calls to search for control dependencies "
1250 "during uninitialized variable analysis.",
1251 1000, 1, 0)
1253 DEFPARAM (PARAM_FSM_SCALE_PATH_STMTS,
1254 "fsm-scale-path-stmts",
1255 "Scale factor to apply to the number of statements in a threading path when comparing to the number of (scaled) blocks.",
1256 2, 1, 10)
1258 DEFPARAM (PARAM_FSM_MAXIMUM_PHI_ARGUMENTS,
1259 "fsm-maximum-phi-arguments",
1260 "Maximum number of arguments a PHI may have before the FSM threader will not try to thread through its block.",
1261 100, 1, 999999)
1263 DEFPARAM (PARAM_FSM_SCALE_PATH_BLOCKS,
1264 "fsm-scale-path-blocks",
1265 "Scale factor to apply to the number of blocks in a threading path when comparing to the number of (scaled) statements.",
1266 3, 1, 10)
1268 DEFPARAM (PARAM_MAX_FSM_THREAD_PATH_INSNS,
1269 "max-fsm-thread-path-insns",
1270 "Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path.",
1271 100, 1, 999999)
1273 DEFPARAM (PARAM_MAX_FSM_THREAD_LENGTH,
1274 "max-fsm-thread-length",
1275 "Maximum number of basic blocks on a finite state automaton jump thread path.",
1276 10, 1, 999999)
1278 DEFPARAM (PARAM_MAX_FSM_THREAD_PATHS,
1279 "max-fsm-thread-paths",
1280 "Maximum number of new jump thread paths to create for a finite state automaton.",
1281 50, 1, 999999)
1283 DEFPARAM (PARAM_PARLOOPS_CHUNK_SIZE,
1284 "parloops-chunk-size",
1285 "Chunk size of omp schedule for loops parallelized by parloops.",
1286 0, 0, 0)
1288 DEFPARAMENUM5 (PARAM_PARLOOPS_SCHEDULE,
1289 "parloops-schedule",
1290 "Schedule type of omp schedule for loops parallelized by "
1291 "parloops (static, dynamic, guided, auto, runtime).",
1292 static,
1293 static, dynamic, guided, auto, runtime)
1295 DEFPARAM (PARAM_PARLOOPS_MIN_PER_THREAD,
1296 "parloops-min-per-thread",
1297 "Minimum number of iterations per thread of an innermost "
1298 "parallelized loop.",
1299 100, 2, 0)
1301 DEFPARAM (PARAM_MAX_SSA_NAME_QUERY_DEPTH,
1302 "max-ssa-name-query-depth",
1303 "Maximum recursion depth allowed when querying a property of an"
1304 " SSA name.",
1305 3, 1, 10)
1307 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_INSNS,
1308 "max-rtl-if-conversion-insns",
1309 "Maximum number of insns in a basic block to consider for RTL "
1310 "if-conversion.",
1311 10, 0, 99)
1313 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_PREDICTABLE_COST,
1314 "max-rtl-if-conversion-predictable-cost",
1315 "Maximum permissible cost for the sequence that would be "
1316 "generated by the RTL if-conversion pass for a branch that "
1317 "is considered predictable.",
1318 20, 0, 200)
1320 DEFPARAM (PARAM_MAX_RTL_IF_CONVERSION_UNPREDICTABLE_COST,
1321 "max-rtl-if-conversion-unpredictable-cost",
1322 "Maximum permissible cost for the sequence that would be "
1323 "generated by the RTL if-conversion pass for a branch that "
1324 "is considered unpredictable.",
1325 40, 0, 200)
1327 DEFPARAM (PARAM_HSA_GEN_DEBUG_STORES,
1328 "hsa-gen-debug-stores",
1329 "Level of hsa debug stores verbosity.",
1330 0, 0, 1)
1332 DEFPARAM (PARAM_MAX_SPECULATIVE_DEVIRT_MAYDEFS,
1333 "max-speculative-devirt-maydefs",
1334 "Maximum number of may-defs visited when devirtualizing "
1335 "speculatively.", 50, 0, 0)
1337 DEFPARAM (PARAM_MAX_VRP_SWITCH_ASSERTIONS,
1338 "max-vrp-switch-assertions",
1339 "Maximum number of assertions to add along the default "
1340 "edge of a switch statement during VRP.",
1341 10, 0, 0)
1343 DEFPARAM (PARAM_VECT_EPILOGUES_NOMASK,
1344 "vect-epilogues-nomask",
1345 "Enable loop epilogue vectorization using smaller vector size.",
1346 0, 0, 1)
1348 DEFPARAM(PARAM_UNROLL_JAM_MIN_PERCENT,
1349 "unroll-jam-min-percent",
1350 "Minimum percentage of memrefs that must go away for unroll-and-jam to be considered profitable.",
1351 1, 0, 100)
1353 DEFPARAM(PARAM_UNROLL_JAM_MAX_UNROLL,
1354 "unroll-jam-max-unroll",
1355 "Maximum unroll factor for the unroll-and-jam transformation.",
1356 4, 0, 0)
1358 DEFPARAM(PARAM_AVOID_FMA_MAX_BITS,
1359 "avoid-fma-max-bits",
1360 "Maximum number of bits for which we avoid creating FMAs.",
1361 0, 0, 512)
1365 Local variables:
1366 mode:c
1367 End: