]> git.ipfire.org Git - thirdparty/gcc.git/blame - gcc/params.def
re PR testsuite/38164 (gcc.target/i386/amd64-abi-3.c fails at -m64 on i686-apple...
[thirdparty/gcc.git] / gcc / params.def
CommitLineData
c6d9a88c 1/* params.def - Run-time parameters.
3d8864c0
SP
2 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
3 Free Software Foundation, Inc.
c6d9a88c
MM
4 Written by Mark Mitchell <mark@codesourcery.com>.
5
1322177d 6This file is part of GCC.
c6d9a88c 7
1322177d
LB
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
9dcd6f09 10Software Foundation; either version 3, or (at your option) any later
1322177d 11version.
c6d9a88c 12
1322177d
LB
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
c6d9a88c
MM
17
18You should have received a copy of the GNU General Public License
9dcd6f09
NC
19along with GCC; see the file COPYING3. If not see
20<http://www.gnu.org/licenses/>. */
c6d9a88c
MM
21
22/* This file contains definitions for language-independent
1eb68dca 23 parameters. The DEFPARAM macro takes 6 arguments:
c6d9a88c 24
0443f602 25 - The enumeral corresponding to this parameter.
c6d9a88c
MM
26
27 - The name that can be used to set this parameter using the
28 command-line option `--param <name>=<value>'.
29
30 - A help string explaining how the parameter is used.
31
1c4c47db
JO
32 - A default value for the parameter.
33
9e7705cb 34 - The minimum acceptable value for the parameter.
1eb68dca 35
9e7705cb 36 - The maximum acceptable value for the parameter (if greater than
1eb68dca
KZ
37 the minimum).
38
1c4c47db 39 Be sure to add an entry to invoke.texi summarizing the parameter. */
c6d9a88c 40
61b58001
BE
41/* The maximum structure size at which the scalar replacement of
42 aggregates (SRA) pass will perform block copies. The default
43 value, 0, implies that GCC will select the most appropriate size
44 itself. */
45DEFPARAM (PARAM_SRA_MAX_STRUCTURE_SIZE,
46 "sra-max-structure-size",
460f84ed
RH
47 "The maximum structure size (in bytes) for which GCC will "
48 "use by-element copies",
49 0, 0, 0)
50
51/* The maximum number of structure fields which the SRA pass will
52 instantiate to avoid block copies. The default value, 0, implies
53 that GCC will select the appropriate value itself. */
54DEFPARAM (PARAM_SRA_MAX_STRUCTURE_COUNT,
55 "sra-max-structure-count",
56 "The maximum number of structure fields for which GCC will "
57 "use by-element copies",
e06c0feb 58 0, 0, 0)
61b58001
BE
59
60/* The ratio between instantiated fields and the complete structure
61 size. We say that if the ratio of the number of bytes in
62 instantiated fields to the number of bytes in the complete
460f84ed
RH
63 structure exceeds this parameter, or if the number of instantiated
64 fields to the total number of fields exceeds this parameter, then
65 block copies are not used. The default is 75%. */
61b58001
BE
66DEFPARAM (PARAM_SRA_FIELD_STRUCTURE_RATIO,
67 "sra-field-structure-ratio",
e06c0feb
NS
68 "The threshold ratio between instantiated fields and the total structure size",
69 75, 0, 100)
61b58001 70
ea429753 71/* The threshold ratio between current and hottest structure counts.
e1dc98b2 72 We say that if the ratio of the current structure count,
ea429753 73 calculated by profiling, to the hottest structure count
e1dc98b2
OG
74 in the program is less than this parameter, then structure
75 reorganization is not applied. The default is 10%. */
76DEFPARAM (PARAM_STRUCT_REORG_COLD_STRUCT_RATIO,
77 "struct-reorg-cold-struct-ratio",
ea429753 78 "The threshold ratio between current and hottest structure counts",
e1dc98b2
OG
79 10, 0, 100)
80
3a4fd356
JH
81/* When branch is predicted to be taken with probability lower than this
82 threshold (in percent), then it is considered well predictable. */
83DEFPARAM (PARAM_PREDICTABLE_BRANCH_OUTCOME,
84 "predictable-branch-outcome",
85 "Maximal esitmated outcome of branch considered predictable",
86 2, 0, 50)
87
a6227154
KG
88/* The single function inlining limit. This is the maximum size
89 of a function counted in internal gcc instructions (not in
90 real machine instructions) that is eligible for inlining
91 by the tree inliner.
e5c4f28a 92 The default value is 450.
a6227154 93 Only functions marked inline (or methods defined in the class
e5c4f28a 94 definition for C++) are affected by this.
a6227154
KG
95 There are more restrictions to inlining: If inlined functions
96 call other functions, the already inlined instructions are
97 counted and once the recursive inline limit (see
98 "max-inline-insns" parameter) is exceeded, the acceptable size
99 gets decreased. */
100DEFPARAM (PARAM_MAX_INLINE_INSNS_SINGLE,
101 "max-inline-insns-single",
bc522472 102 "The maximum number of instructions in a single function eligible for inlining",
e5c4f28a 103 450, 0, 0)
a6227154 104
bc522472
KG
105/* The single function inlining limit for functions that are
106 inlined by virtue of -finline-functions (-O3).
107 This limit should be chosen to be below or equal to the limit
108 that is applied to functions marked inlined (or defined in the
109 class declaration in C++) given by the "max-inline-insns-single"
110 parameter.
e5c4f28a 111 The default value is 90. */
bc522472
KG
112DEFPARAM (PARAM_MAX_INLINE_INSNS_AUTO,
113 "max-inline-insns-auto",
114 "The maximum number of instructions when automatically inlining",
e5c4f28a 115 90, 0, 0)
bc522472 116
6de9cd9a
DN
117DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE,
118 "max-inline-insns-recursive",
119 "The maximum number of instructions inline function can grow to via recursive inlining",
e5c4f28a 120 450, 0, 0)
6de9cd9a
DN
121
122DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO,
123 "max-inline-insns-recursive-auto",
124 "The maximum number of instructions non-inline function can grow to via recursive inlining",
e5c4f28a 125 450, 0, 0)
6de9cd9a
DN
126
127DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH,
128 "max-inline-recursive-depth",
129 "The maximum depth of recursive inlining for inline functions",
e06c0feb 130 8, 0, 0)
6de9cd9a
DN
131
132DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO,
133 "max-inline-recursive-depth-auto",
134 "The maximum depth of recursive inlining for non-inline functions",
e06c0feb 135 8, 0, 0)
6de9cd9a 136
c5a4444c
JH
137DEFPARAM (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY,
138 "min-inline-recursive-probability",
139 "Inline recursively only when the probability of call being executed exceeds the parameter",
140 10, 0, 0)
141
f37a4f14
RE
142/* Limit the number of expansions created by the variable expansion
143 optimization to avoid register pressure. */
144DEFPARAM (PARAM_MAX_VARIABLE_EXPANSIONS,
145 "max-variable-expansions-in-unroller",
5fa534e3 146 "If -fvariable-expansion-in-unroller is used, the maximum number of times that an individual variable will be expanded during loop unrolling",
e06c0feb 147 1, 0, 0)
f37a4f14 148
acdc40df
DN
149/* Limit loop autovectorization to loops with large enough iteration count. */
150DEFPARAM (PARAM_MIN_VECT_LOOP_BOUND,
151 "min-vect-loop-bound",
152 "If -ftree-vectorize is used, the minimal loop bound of a loop to be considered for vectorization",
8d888559 153 1, 1, 0)
acdc40df 154
0443f602
JO
155/* The maximum number of instructions to consider when looking for an
156 instruction to fill a delay slot. If more than this arbitrary
157 number of instructions is searched, the time savings from filling
158 the delay slot will be minimal so stop searching. Increasing
159 values mean more aggressive optimization, making the compile time
160 increase with probably small improvement in executable run time. */
161DEFPARAM (PARAM_MAX_DELAY_SLOT_INSN_SEARCH,
162 "max-delay-slot-insn-search",
163 "The maximum number of instructions to consider to fill a delay slot",
e06c0feb 164 100, 0, 0)
0443f602 165
d5d063d7
JO
166/* When trying to fill delay slots, the maximum number of instructions
167 to consider when searching for a block with valid live register
168 information. Increasing this arbitrarily chosen value means more
169 aggressive optimization, increasing the compile time. This
170 parameter should be removed when the delay slot code is rewritten
171 to maintain the control-flow graph. */
172DEFPARAM(PARAM_MAX_DELAY_SLOT_LIVE_SEARCH,
173 "max-delay-slot-live-search",
174 "The maximum number of instructions to consider to find accurate live register information",
e06c0feb 175 333, 0, 0)
d5d063d7 176
4a121cc3 177/* This parameter limits the number of branch elements that the
ff7cc307 178 scheduler will track anti-dependencies through without resetting
4a121cc3 179 the tracking mechanism. Large functions with few calls or barriers
ff7cc307 180 can generate lists containing many 1000's of dependencies. Generally
4a121cc3
AM
181 the compiler either uses all available memory, or runs for far too long. */
182DEFPARAM(PARAM_MAX_PENDING_LIST_LENGTH,
183 "max-pending-list-length",
184 "The maximum length of scheduling's pending operations list",
e06c0feb 185 32, 0, 0)
4a121cc3 186
b58b1157
JH
187DEFPARAM(PARAM_LARGE_FUNCTION_INSNS,
188 "large-function-insns",
189 "The size of function body to be considered large",
e5c4f28a 190 2700, 0, 0)
b58b1157
JH
191DEFPARAM(PARAM_LARGE_FUNCTION_GROWTH,
192 "large-function-growth",
2cc98056 193 "Maximal growth due to inlining of large function (in percent)",
e06c0feb 194 100, 0, 0)
b4f32d07
JH
195DEFPARAM(PARAM_LARGE_UNIT_INSNS,
196 "large-unit-insns",
197 "The size of translation unit to be considered large",
198 10000, 0, 0)
b58b1157
JH
199DEFPARAM(PARAM_INLINE_UNIT_GROWTH,
200 "inline-unit-growth",
2cc98056 201 "how much can given compilation unit grow because of the inlining (in percent)",
d562c668 202 30, 0, 0)
5e45130d
JH
203DEFPARAM(PARAM_IPCP_UNIT_GROWTH,
204 "ipcp-unit-growth",
205 "how much can given compilation unit grow because of the interprocedural constant propagation (in percent)",
206 10, 0, 0)
e5c4f28a
RG
207DEFPARAM(PARAM_INLINE_CALL_COST,
208 "inline-call-cost",
2e0ea515 209 "expense of call operation relative to ordinary arithmetic operations",
f2879759 210 12, 0, 0)
ff28a94d
JH
211DEFPARAM(PARAM_LARGE_STACK_FRAME,
212 "large-stack-frame",
213 "The size of stack frame to be considered large",
214 256, 0, 0)
215DEFPARAM(PARAM_STACK_FRAME_GROWTH,
216 "large-stack-frame-growth",
217 "Maximal stack frame growth due to inlining (in percent)",
218 1000, 0, 0)
b58b1157 219
f1fa37ff
MM
220/* The GCSE optimization will be disabled if it would require
221 significantly more memory than this value. */
222DEFPARAM(PARAM_MAX_GCSE_MEMORY,
223 "max-gcse-memory",
224 "The maximum amount of memory to be allocated by GCSE",
e06c0feb 225 50 * 1024 * 1024, 0, 0)
991b6592 226/* The number of repetitions of copy/const prop and PRE to run. */
740f35a0
DB
227DEFPARAM(PARAM_MAX_GCSE_PASSES,
228 "max-gcse-passes",
229 "The maximum number of passes to make when doing GCSE",
e06c0feb 230 1, 1, 0)
f9957958
MH
231/* This is the threshold ratio when to perform partial redundancy
232 elimination after reload. We perform partial redundancy elimination
233 when the following holds:
234 (Redundant load execution count)
235 ------------------------------- >= GCSE_AFTER_RELOAD_PARTIAL_FRACTION
236 (Added loads execution count) */
237DEFPARAM(PARAM_GCSE_AFTER_RELOAD_PARTIAL_FRACTION,
238 "gcse-after-reload-partial-fraction",
c85ce869 239 "The threshold ratio for performing partial redundancy elimination after reload",
e06c0feb 240 3, 0, 0)
f9957958
MH
241/* This is the threshold ratio of the critical edges execution count compared to
242 the redundant loads execution count that permits performing the load
243 redundancy elimination in gcse after reload. */
244DEFPARAM(PARAM_GCSE_AFTER_RELOAD_CRITICAL_FRACTION,
245 "gcse-after-reload-critical-fraction",
c85ce869 246 "The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload",
e06c0feb 247 10, 0, 0)
03e9dbc9 248/* This parameter limits the number of insns in a loop that will be unrolled,
701ad47e
JH
249 and by how much the loop is unrolled.
250
251 This limit should be at most half of the peeling limits: loop unroller
252 decides to not unroll loops that iterate fewer than 2*number of allowed
a1105617 253 unrollings and thus we would have loops that are neither peeled or unrolled
701ad47e 254 otherwise. */
03e9dbc9
MM
255DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
256 "max-unrolled-insns",
257 "The maximum number of instructions to consider to unroll in a loop",
e06c0feb 258 200, 0, 0)
b17d5d7c
ZD
259/* This parameter limits how many times the loop is unrolled depending
260 on number of insns really executed in each iteration. */
261DEFPARAM(PARAM_MAX_AVERAGE_UNROLLED_INSNS,
262 "max-average-unrolled-insns",
263 "The maximum number of instructions to consider to unroll in a loop on average",
e06c0feb 264 80, 0, 0)
b17d5d7c
ZD
265/* The maximum number of unrollings of a single loop. */
266DEFPARAM(PARAM_MAX_UNROLL_TIMES,
267 "max-unroll-times",
268 "The maximum number of unrollings of a single loop",
e06c0feb 269 8, 0, 0)
b17d5d7c
ZD
270/* The maximum number of insns of a peeled loop. */
271DEFPARAM(PARAM_MAX_PEELED_INSNS,
272 "max-peeled-insns",
273 "The maximum number of insns of a peeled loop",
e06c0feb 274 400, 0, 0)
b17d5d7c
ZD
275/* The maximum number of peelings of a single loop. */
276DEFPARAM(PARAM_MAX_PEEL_TIMES,
277 "max-peel-times",
278 "The maximum number of peelings of a single loop",
e06c0feb 279 16, 0, 0)
b17d5d7c
ZD
280/* The maximum number of insns of a peeled loop. */
281DEFPARAM(PARAM_MAX_COMPLETELY_PEELED_INSNS,
282 "max-completely-peeled-insns",
283 "The maximum number of insns of a completely peeled loop",
e06c0feb 284 400, 0, 0)
b17d5d7c
ZD
285/* The maximum number of peelings of a single loop that is peeled completely. */
286DEFPARAM(PARAM_MAX_COMPLETELY_PEEL_TIMES,
287 "max-completely-peel-times",
288 "The maximum number of peelings of a single loop that is peeled completely",
e06c0feb 289 16, 0, 0)
b17d5d7c
ZD
290/* The maximum number of insns of a peeled loop that rolls only once. */
291DEFPARAM(PARAM_MAX_ONCE_PEELED_INSNS,
292 "max-once-peeled-insns",
293 "The maximum number of insns of a peeled loop that rolls only once",
e06c0feb 294 400, 0, 0)
194734e9 295
617b465c
ZD
296/* The maximum number of insns of an unswitched loop. */
297DEFPARAM(PARAM_MAX_UNSWITCH_INSNS,
298 "max-unswitch-insns",
299 "The maximum number of insns of an unswitched loop",
e06c0feb 300 50, 0, 0)
617b465c
ZD
301/* The maximum level of recursion in unswitch_single_loop. */
302DEFPARAM(PARAM_MAX_UNSWITCH_LEVEL,
303 "max-unswitch-level",
304 "The maximum number of unswitchings in a single loop",
e06c0feb 305 3, 0, 0)
617b465c 306
e9eb809d
ZD
307/* The maximum number of iterations of a loop the brute force algorithm
308 for analysis of # of iterations of the loop tries to evaluate. */
309DEFPARAM(PARAM_MAX_ITERATIONS_TO_TRACK,
310 "max-iterations-to-track",
e06c0feb
NS
311 "Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates",
312 1000, 0, 0)
45b9a14b
BS
313/* A cutoff to avoid costly computations of the number of iterations in
314 the doloop transformation. */
315DEFPARAM(PARAM_MAX_ITERATIONS_COMPUTATION_COST,
316 "max-iterations-computation-cost",
317 "Bound on the cost of an expression to compute the number of iterations",
318 10, 0, 0)
e9eb809d 319
e5626198
AZ
320/* This parameter is used to tune SMS MAX II calculations. */
321DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
322 "sms-max-ii-factor",
e06c0feb
NS
323 "A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop",
324 100, 0, 0)
e5626198
AZ
325DEFPARAM(PARAM_SMS_DFA_HISTORY,
326 "sms-dfa-history",
5fa534e3 327 "The number of cycles the swing modulo scheduler considers when checking conflicts using DFA",
e06c0feb 328 0, 0, 0)
e5626198
AZ
329DEFPARAM(PARAM_SMS_LOOP_AVERAGE_COUNT_THRESHOLD,
330 "sms-loop-average-count-threshold",
e06c0feb
NS
331 "A threshold on the average loop count considered by the swing modulo scheduler",
332 0, 0, 0)
e5626198 333
194734e9
JH
334DEFPARAM(HOT_BB_COUNT_FRACTION,
335 "hot-bb-count-fraction",
e06c0feb
NS
336 "Select fraction of the maximal count of repetitions of basic block in program given basic block needs to have to be considered hot",
337 10000, 0, 0)
194734e9
JH
338DEFPARAM(HOT_BB_FREQUENCY_FRACTION,
339 "hot-bb-frequency-fraction",
e06c0feb
NS
340 "Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot",
341 1000, 0, 0)
95b9a3a5 342
edbed3d3
JH
343DEFPARAM (PARAM_ALIGN_THRESHOLD,
344 "align-threshold",
345 "Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment",
346 100, 0, 0)
347
348DEFPARAM (PARAM_ALIGN_LOOP_ITERATIONS,
349 "align-loop-iterations",
350 "Loops iterating at least selected number of iterations will get loop alignement.",
351 4, 0, 0)
352
95b9a3a5
JH
353/* For guessed profiles, the loops having unknown number of iterations
354 are predicted to iterate relatively few (10) times at average.
355 For functions containing one loop with large known number of iterations
356 and other loops having unbounded loops we would end up predicting all
c83eecad 357 the other loops cold that is not usually the case. So we need to artificially
95b9a3a5
JH
358 flatten the profile.
359
6416ae7f 360 We need to cut the maximal predicted iterations to large enough iterations
95b9a3a5
JH
361 so the loop appears important, but safely within HOT_BB_COUNT_FRACTION
362 range. */
363
364DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
365 "max-predicted-iterations",
366 "The maximum number of loop iterations we predict statically",
367 100, 0, 0)
5c856b23
JH
368DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK,
369 "tracer-dynamic-coverage-feedback",
e06c0feb
NS
370 "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available",
371 95, 0, 100)
5c856b23
JH
372DEFPARAM(TRACER_DYNAMIC_COVERAGE,
373 "tracer-dynamic-coverage",
e06c0feb
NS
374 "The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available",
375 75, 0, 100)
5c856b23
JH
376DEFPARAM(TRACER_MAX_CODE_GROWTH,
377 "tracer-max-code-growth",
2cc98056 378 "Maximal code growth caused by tail duplication (in percent)",
e06c0feb 379 100, 0, 0)
5c856b23
JH
380DEFPARAM(TRACER_MIN_BRANCH_RATIO,
381 "tracer-min-branch-ratio",
e06c0feb
NS
382 "Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent)",
383 10, 0, 100)
5c856b23
JH
384DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK,
385 "tracer-min-branch-probability-feedback",
e06c0feb
NS
386 "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available",
387 80, 0, 100)
5c856b23
JH
388DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY,
389 "tracer-min-branch-probability",
e06c0feb
NS
390 "Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available",
391 50, 0, 100)
3788cc17 392
5f24e0dc
RH
393/* The maximum number of incoming edges to consider for crossjumping. */
394DEFPARAM(PARAM_MAX_CROSSJUMP_EDGES,
395 "max-crossjump-edges",
396 "The maximum number of incoming edges to consider for crossjumping",
e06c0feb 397 100, 0, 0)
5f24e0dc 398
12183e0f
PH
399/* The minimum number of matching instructions to consider for crossjumping. */
400DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
401 "min-crossjump-insns",
402 "The minimum number of matching instructions to consider for crossjumping",
e06c0feb 403 5, 0, 0)
12183e0f 404
f935b9e0
DE
405/* The maximum number expansion factor when copying basic blocks. */
406DEFPARAM(PARAM_MAX_GROW_COPY_BB_INSNS,
407 "max-grow-copy-bb-insns",
408 "The maximum expansion factor when copying basic blocks",
409 8, 0, 0)
410
bbcb0c05
SB
411/* The maximum number of insns to duplicate when unfactoring computed gotos. */
412DEFPARAM(PARAM_MAX_GOTO_DUPLICATION_INSNS,
413 "max-goto-duplication-insns",
414 "The maximum number of insns to duplicate when unfactoring computed gotos",
415 8, 0, 0)
416
9bf8cfbf
ZD
417/* The maximum length of path considered in cse. */
418DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
419 "max-cse-path-length",
2cc98056 420 "The maximum length of path considered in cse",
e06c0feb 421 10, 0, 0)
95b9a3a5 422DEFPARAM(PARAM_MAX_CSE_INSNS,
921b02cd 423 "max-cse-insns",
95b9a3a5
JH
424 "The maximum instructions CSE process before flushing",
425 1000, 0, 0)
9bf8cfbf 426
a7e5372d
ZD
427/* The cost of expression in loop invariant motion that is considered
428 expensive. */
429DEFPARAM(PARAM_LIM_EXPENSIVE,
430 "lim-expensive",
431 "The minimum cost of an expensive expression in the loop invariant motion",
e06c0feb 432 20, 0, 0)
a7e5372d 433
8b11a64c
ZD
434/* Bound on number of candidates for induction variables below that
435 all candidates are considered for each use in induction variable
436 optimizations. */
437
438DEFPARAM(PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND,
439 "iv-consider-all-candidates-bound",
440 "Bound on number of candidates below that all candidates are considered in iv optimizations",
e06c0feb 441 30, 0, 0)
8b11a64c
ZD
442
443/* The induction variable optimizations give up on loops that contain more
444 induction variable uses. */
445
446DEFPARAM(PARAM_IV_MAX_CONSIDERED_USES,
447 "iv-max-considered-uses",
448 "Bound on number of iv uses in loop optimized in iv optimizations",
e06c0feb 449 250, 0, 0)
8b11a64c 450
36f5ada1
ZD
451/* If there are at most this number of ivs in the set, try removing unnecessary
452 ivs from the set always. */
453
454DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
455 "iv-always-prune-cand-set-bound",
456 "If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization",
457 10, 0, 0)
458
2412d35c
SP
459DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
460 "scev-max-expr-size",
461 "Bound on size of expressions used in the scalar evolutions analyzer",
462 20, 0, 0)
463
3d8864c0
SP
464DEFPARAM(PARAM_OMEGA_MAX_VARS,
465 "omega-max-vars",
466 "Bound on the number of variables in Omega constraint systems",
467 128, 0, 0)
468
469DEFPARAM(PARAM_OMEGA_MAX_GEQS,
470 "omega-max-geqs",
471 "Bound on the number of inequalities in Omega constraint systems",
472 256, 0, 0)
473
474DEFPARAM(PARAM_OMEGA_MAX_EQS,
475 "omega-max-eqs",
476 "Bound on the number of equalities in Omega constraint systems",
477 128, 0, 0)
478
479DEFPARAM(PARAM_OMEGA_MAX_WILD_CARDS,
480 "omega-max-wild-cards",
481 "Bound on the number of wild cards in Omega constraint systems",
482 18, 0, 0)
483
484DEFPARAM(PARAM_OMEGA_HASH_TABLE_SIZE,
485 "omega-hash-table-size",
486 "Bound on the size of the hash table in Omega constraint systems",
487 550, 0, 0)
488
489DEFPARAM(PARAM_OMEGA_MAX_KEYS,
490 "omega-max-keys",
491 "Bound on the number of keys in Omega constraint systems",
492 500, 0, 0)
493
494DEFPARAM(PARAM_OMEGA_ELIMINATE_REDUNDANT_CONSTRAINTS,
495 "omega-eliminate-redundant-constraints",
496 "When set to 1, use expensive methods to eliminate all redundant constraints",
497 0, 0, 1)
498
bc1edb77
VK
499DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIGNMENT_CHECKS,
500 "vect-max-version-for-alignment-checks",
501 "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check",
c12cc930
KB
502 6, 0, 0)
503
bc1edb77
VK
504DEFPARAM(PARAM_VECT_MAX_VERSION_FOR_ALIAS_CHECKS,
505 "vect-max-version-for-alias-checks",
506 "Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check",
507 10, 0, 0)
508
c65ecebc
JH
509DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
510 "max-cselib-memory-locations",
511 "The maximum memory locations recorded by cselib",
e06c0feb 512 500, 0, 0)
c65ecebc 513
3788cc17
ZW
514#ifdef ENABLE_GC_ALWAYS_COLLECT
515# define GGC_MIN_EXPAND_DEFAULT 0
737c38d1 516# define GGC_MIN_HEAPSIZE_DEFAULT 0
3788cc17
ZW
517#else
518# define GGC_MIN_EXPAND_DEFAULT 30
737c38d1 519# define GGC_MIN_HEAPSIZE_DEFAULT 4096
3788cc17
ZW
520#endif
521
522DEFPARAM(GGC_MIN_EXPAND,
523 "ggc-min-expand",
e06c0feb
NS
524 "Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap",
525 GGC_MIN_EXPAND_DEFAULT, 0, 0)
3788cc17 526
3788cc17
ZW
527DEFPARAM(GGC_MIN_HEAPSIZE,
528 "ggc-min-heapsize",
2cc98056 529 "Minimum heap size before we start collecting garbage, in kilobytes",
e06c0feb 530 GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
737c38d1
GK
531
532#undef GGC_MIN_EXPAND_DEFAULT
533#undef GGC_MIN_HEAPSIZE_DEFAULT
3788cc17 534
0bcf8261
JH
535DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
536 "max-reload-search-insns",
537 "The maximum number of instructions to search backward when looking for equivalent reload",
e06c0feb 538 100, 0, 0)
0bcf8261 539
6de9cd9a
DN
540DEFPARAM(PARAM_MAX_ALIASED_VOPS,
541 "max-aliased-vops",
e9e0aa2c
DN
542 "The maximum number of virtual operators that a function is allowed to have before triggering memory partitioning heuristics",
543 100, 0, 0)
544
545DEFPARAM(PARAM_AVG_ALIASED_VOPS,
546 "avg-aliased-vops",
547 "The average number of virtual operators that memory statements are allowed to have before triggering memory partitioning heuristics",
548 1, 0, 0)
6de9cd9a 549
f72c6b56
DE
550DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
551 "max-sched-region-blocks",
552 "The maximum number of blocks in a region to be considered for interblock scheduling",
e06c0feb 553 10, 0, 0)
f72c6b56
DE
554
555DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
556 "max-sched-region-insns",
557 "The maximum number of insns in a region to be considered for interblock scheduling",
e06c0feb 558 100, 0, 0)
f72c6b56 559
e855c69d
AB
560DEFPARAM(PARAM_MAX_PIPELINE_REGION_BLOCKS,
561 "max-pipeline-region-blocks",
562 "The maximum number of blocks in a region to be considered for interblock scheduling",
563 15, 0, 0)
564
565DEFPARAM(PARAM_MAX_PIPELINE_REGION_INSNS,
566 "max-pipeline-region-insns",
567 "The maximum number of insns in a region to be considered for interblock scheduling",
568 200, 0, 0)
569
6f48c21a
PS
570DEFPARAM(PARAM_MIN_SPEC_PROB,
571 "min-spec-prob",
572 "The minimum probability of reaching a source block for interblock speculative scheduling",
573 40, 0, 0)
574
d08eefb9
MK
575DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
576 "max-sched-extend-regions-iters",
577 "The maximum number of iterations through CFG to extend regions",
bb83aa4b 578 0, 0, 0)
d08eefb9 579
496d7bb0
MK
580DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
581 "max-sched-insn-conflict-delay",
582 "The maximum conflict delay for an insn to be considered for speculative motion",
583 3, 1, 10)
584
585DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
586 "sched-spec-prob-cutoff",
587 "The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
588 40, 0, 100)
589
e855c69d
AB
590DEFPARAM(PARAM_SELSCHED_MAX_LOOKAHEAD,
591 "selsched-max-lookahead",
592 "The maximum size of the lookahead window of selective scheduling",
593 50, 0, 0)
594
595DEFPARAM(PARAM_SELSCHED_MAX_SCHED_TIMES,
596 "selsched-max-sched-times",
597 "Maximum number of times that an insn could be scheduled",
598 2, 0, 0)
599
600DEFPARAM(PARAM_SELSCHED_INSNS_TO_RENAME,
601 "selsched-insns-to-rename",
602 "Maximum number of instructions in the ready list that are considered eligible for renaming",
603 2, 0, 0)
604
605DEFPARAM (PARAM_SCHED_MEM_TRUE_DEP_COST,
606 "sched-mem-true-dep-cost",
607 "Minimal distance between possibly conflicting store and load",
608 1, 0, 0)
609
49c3b9a8
JJ
610DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
611 "max-last-value-rtl",
612 "The maximum number of RTL nodes that can be recorded as combiner's last value",
613 10000, 0, 0)
614
89b0433e
NS
615/* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
616 {signed,unsigned} integral types. This determines N.
617 Experimentation shows 256 to be a good value. */
618DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
619 "integer-share-limit",
620 "The upper bound for sharing integer constants",
e06c0feb 621 256, 2, 2)
89b0433e 622
84d65814
DN
623/* Incremental SSA updates for virtual operands may be very slow if
624 there is a large number of mappings to process. In those cases, it
625 is faster to rewrite the virtual symbols from scratch as if they
626 had been recently introduced. This heuristic cannot be applied to
627 SSA mappings for real SSA names, only symbols kept in FUD chains.
628
629 PARAM_MIN_VIRTUAL_MAPPINGS specifies the minimum number of virtual
630 mappings that should be registered to trigger the heuristic.
631
632 PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO specifies the ratio between
633 mappings and symbols. If the number of virtual mappings is
634 PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO bigger than the number of
635 virtual symbols to be updated, then the updater switches to a full
636 update for those symbols. */
637DEFPARAM (PARAM_MIN_VIRTUAL_MAPPINGS,
638 "min-virtual-mappings",
639 "Minimum number of virtual mappings to consider switching to full virtual renames",
640 100, 0, 0)
641
642DEFPARAM (PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO,
643 "virtual-mappings-ratio",
644 "Ratio between virtual mappings and virtual symbols to do full virtual renames",
645 3, 0, 0)
646
7d69de61
RH
647DEFPARAM (PARAM_SSP_BUFFER_SIZE,
648 "ssp-buffer-size",
649 "The lower bound for a buffer to be considered for stack smashing protection",
650 8, 1, 0)
651
43f31be5
JL
652/* When we thread through a block we have to make copies of the
653 statements within the block. Clearly for large blocks the code
654 duplication is bad.
655
656 PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
657 of statements and PHI nodes allowed in a block which is going to
658 be duplicated for thread jumping purposes.
659
660 Some simple analysis showed that more than 99% of the jump
661 threading opportunities are for blocks with less than 15
662 statements. So we can get the benefits of jump threading
663 without excessive code bloat for pathological cases with the
664 throttle set at 15 statements. */
665DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
666 "max-jump-thread-duplication-stmts",
667 "Maximum number of statements allowed in a block that needs to be duplicated when threading jumps",
668 15, 0, 0)
98035a75
DB
669
670/* This is the maximum number of fields a variable may have before the pointer analysis machinery
671 will stop trying to treat it in a field-sensitive manner.
672 There are programs out there with thousands of fields per structure, and handling them
673 field-sensitively is not worth the cost. */
674DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
675 "max-fields-for-field-sensitive",
676 "Maximum number of fields in a structure before pointer analysis treats the structure as a single variable",
d9338cf0 677 0, 0, 0)
6f8dd94b
EB
678
679DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
680 "max-sched-ready-insns",
681 "The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass",
682 100, 0, 0)
683
47eb5b32
ZD
684/* Prefetching and cache-optimizations related parameters. Default values are
685 usually set by machine description. */
686
687/* The number of insns executed before prefetch is completed. */
688
689DEFPARAM (PARAM_PREFETCH_LATENCY,
690 "prefetch-latency",
691 "The number of insns executed before prefetch is completed",
692 200, 0, 0)
693
694/* The number of prefetches that can run at the same time. */
695
696DEFPARAM (PARAM_SIMULTANEOUS_PREFETCHES,
697 "simultaneous-prefetches",
698 "The number of prefetches that can run at the same time",
699 3, 0, 0)
700
46cb0441 701/* The size of L1 cache in kB. */
47eb5b32
ZD
702
703DEFPARAM (PARAM_L1_CACHE_SIZE,
704 "l1-cache-size",
705 "The size of L1 cache",
46cb0441 706 64, 0, 0)
47eb5b32
ZD
707
708/* The size of L1 cache line in bytes. */
709
710DEFPARAM (PARAM_L1_CACHE_LINE_SIZE,
711 "l1-cache-line-size",
712 "The size of L1 cache line",
713 32, 0, 0)
714
46cb0441
ZD
715/* The size of L2 cache in kB. */
716
717DEFPARAM (PARAM_L2_CACHE_SIZE,
718 "l2-cache-size",
719 "The size of L2 cache",
720 512, 0, 0)
721
7313518b
DG
722/* Whether we should use canonical types rather than deep "structural"
723 type checking. Setting this value to 1 (the default) improves
724 compilation performance in the C++ and Objective-C++ front end;
725 this value should only be set to zero to work around bugs in the
726 canonical type system by disabling it. */
727
728DEFPARAM (PARAM_USE_CANONICAL_TYPES,
729 "use-canonical-types",
730 "Whether to use canonical types",
731 1, 0, 1)
f0ed4cfb
NC
732
733DEFPARAM (PARAM_MAX_PARTIAL_ANTIC_LENGTH,
734 "max-partial-antic-length",
735 "Maximum length of partial antic set when performing tree pre optimization",
736 100, 0, 0)
737
863d2a57
RG
738/* The following is used as a stop-gap limit for cases where really huge
739 SCCs blow up memory and compile-time use too much. If we hit this limit,
740 SCCVN and such FRE and PRE will be not done at all for the current
741 function. */
742
743DEFPARAM (PARAM_SCCVN_MAX_SCC_SIZE,
744 "sccvn-max-scc-size",
745 "Maximum size of a SCC before SCCVN stops processing a function",
746 10000, 10, 0)
747
058e97ec
VM
748DEFPARAM (PARAM_IRA_MAX_LOOPS_NUM,
749 "ira-max-loops-num",
750 "max loops number for regional RA",
30ea859e 751 100, 0, 0)
058e97ec 752
311aab06
VM
753DEFPARAM (PARAM_IRA_MAX_CONFLICT_TABLE_SIZE,
754 "ira-max-conflict-table-size",
755 "max size of conflict table in MB",
7cd06356 756 1000, 0, 0)
311aab06 757
b6e99746
MJ
758/* Switch initialization conversion will refuse to create arrays that are
759 bigger than this parameter times the number of switch branches. */
760
761DEFPARAM (PARAM_SWITCH_CONVERSION_BRANCH_RATIO,
762 "switch-conversion-max-branch-ratio",
763 "The maximum ratio between array size and switch branches for "
764 "a switch conversion to take place",
765 8, 1, 0)
766
c6d9a88c
MM
767/*
768Local variables:
769mode:c
f4b4a3e2
NC
770End:
771*/