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601 lines
24 KiB
Modula-2
601 lines
24 KiB
Modula-2
/* params.def - Run-time parameters.
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Copyright (C) 2001, 2002, 2004, 2005 Free Software Foundation, Inc.
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Written by Mark Mitchell <mark@codesourcery.com>.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA.
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*/
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/* This file contains definitions for language-independent
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parameters. The DEFPARAM macro takes 6 arguments:
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- The enumeral corresponding to this parameter.
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- The name that can be used to set this parameter using the
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command-line option `--param <name>=<value>'.
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- A help string explaining how the parameter is used.
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- A default value for the parameter.
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- The minimum acceptable value for the parameter.
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- The maximum acceptable value for the parameter (if greater than
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the minimum).
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Be sure to add an entry to invoke.texi summarizing the parameter. */
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/* The maximum number of fields in a variable with only implicit uses
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for which structure aliasing will consider trying to track each
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field. The default is 5. */
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DEFPARAM (PARAM_SALIAS_MAX_IMPLICIT_FIELDS,
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"salias-max-implicit-fields",
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"The maximum number of fields in a structure variable without direct structure accesses that GCC will attempt to track separately",
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5, 0, 0)
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/* The maximum number of array elements structure aliasing will decompose
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an array for. The default is 4. */
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DEFPARAM (PARAM_SALIAS_MAX_ARRAY_ELEMENTS,
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"salias-max-array-elements",
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"The maximum number of elements in an array for wich we track its elements separately",
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4, 0, 0)
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/* The maximum structure size at which the scalar replacement of
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aggregates (SRA) pass will perform block copies. The default
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value, 0, implies that GCC will select the most appropriate size
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itself. */
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DEFPARAM (PARAM_SRA_MAX_STRUCTURE_SIZE,
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"sra-max-structure-size",
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"The maximum structure size (in bytes) for which GCC will "
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"use by-element copies",
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0, 0, 0)
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/* The maximum number of structure fields which the SRA pass will
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instantiate to avoid block copies. The default value, 0, implies
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that GCC will select the appropriate value itself. */
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DEFPARAM (PARAM_SRA_MAX_STRUCTURE_COUNT,
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"sra-max-structure-count",
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"The maximum number of structure fields for which GCC will "
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"use by-element copies",
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0, 0, 0)
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/* The ratio between instantiated fields and the complete structure
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size. We say that if the ratio of the number of bytes in
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instantiated fields to the number of bytes in the complete
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structure exceeds this parameter, or if the number of instantiated
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fields to the total number of fields exceeds this parameter, then
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block copies are not used. The default is 75%. */
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DEFPARAM (PARAM_SRA_FIELD_STRUCTURE_RATIO,
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"sra-field-structure-ratio",
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"The threshold ratio between instantiated fields and the total structure size",
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75, 0, 100)
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/* The single function inlining limit. This is the maximum size
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of a function counted in internal gcc instructions (not in
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real machine instructions) that is eligible for inlining
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by the tree inliner.
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The default value is 450.
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Only functions marked inline (or methods defined in the class
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definition for C++) are affected by this.
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There are more restrictions to inlining: If inlined functions
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call other functions, the already inlined instructions are
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counted and once the recursive inline limit (see
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"max-inline-insns" parameter) is exceeded, the acceptable size
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gets decreased. */
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DEFPARAM (PARAM_MAX_INLINE_INSNS_SINGLE,
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"max-inline-insns-single",
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"The maximum number of instructions in a single function eligible for inlining",
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450, 0, 0)
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/* The single function inlining limit for functions that are
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inlined by virtue of -finline-functions (-O3).
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This limit should be chosen to be below or equal to the limit
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that is applied to functions marked inlined (or defined in the
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class declaration in C++) given by the "max-inline-insns-single"
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parameter.
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The default value is 90. */
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DEFPARAM (PARAM_MAX_INLINE_INSNS_AUTO,
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"max-inline-insns-auto",
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"The maximum number of instructions when automatically inlining",
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90, 0, 0)
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DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE,
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"max-inline-insns-recursive",
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"The maximum number of instructions inline function can grow to via recursive inlining",
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450, 0, 0)
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DEFPARAM (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO,
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"max-inline-insns-recursive-auto",
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"The maximum number of instructions non-inline function can grow to via recursive inlining",
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450, 0, 0)
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DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH,
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"max-inline-recursive-depth",
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"The maximum depth of recursive inlining for inline functions",
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8, 0, 0)
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DEFPARAM (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO,
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"max-inline-recursive-depth-auto",
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"The maximum depth of recursive inlining for non-inline functions",
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8, 0, 0)
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DEFPARAM (PARAM_MIN_INLINE_RECURSIVE_PROBABILITY,
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"min-inline-recursive-probability",
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"Inline recursively only when the probability of call being executed exceeds the parameter",
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10, 0, 0)
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/* Limit the number of expansions created by the variable expansion
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optimization to avoid register pressure. */
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DEFPARAM (PARAM_MAX_VARIABLE_EXPANSIONS,
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"max-variable-expansions-in-unroller",
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"If -fvariable-expansion-in-unroller is used, the maximum number of times that an individual variable will be expanded during loop unrolling",
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1, 0, 0)
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/* The maximum number of instructions to consider when looking for an
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instruction to fill a delay slot. If more than this arbitrary
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number of instructions is searched, the time savings from filling
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the delay slot will be minimal so stop searching. Increasing
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values mean more aggressive optimization, making the compile time
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increase with probably small improvement in executable run time. */
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DEFPARAM (PARAM_MAX_DELAY_SLOT_INSN_SEARCH,
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"max-delay-slot-insn-search",
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"The maximum number of instructions to consider to fill a delay slot",
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100, 0, 0)
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/* When trying to fill delay slots, the maximum number of instructions
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to consider when searching for a block with valid live register
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information. Increasing this arbitrarily chosen value means more
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aggressive optimization, increasing the compile time. This
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parameter should be removed when the delay slot code is rewritten
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to maintain the control-flow graph. */
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DEFPARAM(PARAM_MAX_DELAY_SLOT_LIVE_SEARCH,
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"max-delay-slot-live-search",
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"The maximum number of instructions to consider to find accurate live register information",
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333, 0, 0)
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/* This parameter limits the number of branch elements that the
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scheduler will track anti-dependencies through without resetting
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the tracking mechanism. Large functions with few calls or barriers
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can generate lists containing many 1000's of dependencies. Generally
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the compiler either uses all available memory, or runs for far too long. */
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DEFPARAM(PARAM_MAX_PENDING_LIST_LENGTH,
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"max-pending-list-length",
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"The maximum length of scheduling's pending operations list",
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32, 0, 0)
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DEFPARAM(PARAM_LARGE_FUNCTION_INSNS,
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"large-function-insns",
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"The size of function body to be considered large",
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2700, 0, 0)
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DEFPARAM(PARAM_LARGE_FUNCTION_GROWTH,
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"large-function-growth",
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"Maximal growth due to inlining of large function (in percent)",
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100, 0, 0)
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DEFPARAM(PARAM_LARGE_UNIT_INSNS,
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"large-unit-insns",
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"The size of translation unit to be considered large",
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10000, 0, 0)
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DEFPARAM(PARAM_INLINE_UNIT_GROWTH,
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"inline-unit-growth",
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"how much can given compilation unit grow because of the inlining (in percent)",
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50, 0, 0)
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DEFPARAM(PARAM_INLINE_CALL_COST,
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"inline-call-cost",
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"expense of call operation relative to ordinary arithmetic operations",
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16, 0, 0)
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/* The GCSE optimization will be disabled if it would require
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significantly more memory than this value. */
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DEFPARAM(PARAM_MAX_GCSE_MEMORY,
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"max-gcse-memory",
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"The maximum amount of memory to be allocated by GCSE",
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50 * 1024 * 1024, 0, 0)
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/* The number of repetitions of copy/const prop and PRE to run. */
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DEFPARAM(PARAM_MAX_GCSE_PASSES,
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"max-gcse-passes",
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"The maximum number of passes to make when doing GCSE",
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1, 1, 0)
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/* This is the threshold ratio when to perform partial redundancy
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elimination after reload. We perform partial redundancy elimination
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when the following holds:
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(Redundant load execution count)
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------------------------------- >= GCSE_AFTER_RELOAD_PARTIAL_FRACTION
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(Added loads execution count) */
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DEFPARAM(PARAM_GCSE_AFTER_RELOAD_PARTIAL_FRACTION,
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"gcse-after-reload-partial-fraction",
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"The threshold ratio for performing partial redundancy elimination after reload",
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3, 0, 0)
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/* This is the threshold ratio of the critical edges execution count compared to
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the redundant loads execution count that permits performing the load
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redundancy elimination in gcse after reload. */
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DEFPARAM(PARAM_GCSE_AFTER_RELOAD_CRITICAL_FRACTION,
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"gcse-after-reload-critical-fraction",
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"The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload",
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10, 0, 0)
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/* This parameter limits the number of insns in a loop that will be unrolled,
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and by how much the loop is unrolled.
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This limit should be at most half of the peeling limits: loop unroller
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decides to not unroll loops that iterate fewer than 2*number of allowed
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unrollings and thus we would have loops that are neither peeled or unrolled
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otherwise. */
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DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
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"max-unrolled-insns",
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"The maximum number of instructions to consider to unroll in a loop",
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200, 0, 0)
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/* This parameter limits how many times the loop is unrolled depending
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on number of insns really executed in each iteration. */
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DEFPARAM(PARAM_MAX_AVERAGE_UNROLLED_INSNS,
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"max-average-unrolled-insns",
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"The maximum number of instructions to consider to unroll in a loop on average",
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80, 0, 0)
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/* The maximum number of unrollings of a single loop. */
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DEFPARAM(PARAM_MAX_UNROLL_TIMES,
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"max-unroll-times",
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"The maximum number of unrollings of a single loop",
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8, 0, 0)
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/* The maximum number of insns of a peeled loop. */
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DEFPARAM(PARAM_MAX_PEELED_INSNS,
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"max-peeled-insns",
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"The maximum number of insns of a peeled loop",
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400, 0, 0)
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/* The maximum number of peelings of a single loop. */
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DEFPARAM(PARAM_MAX_PEEL_TIMES,
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"max-peel-times",
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"The maximum number of peelings of a single loop",
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16, 0, 0)
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/* The maximum number of insns of a peeled loop. */
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DEFPARAM(PARAM_MAX_COMPLETELY_PEELED_INSNS,
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"max-completely-peeled-insns",
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"The maximum number of insns of a completely peeled loop",
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400, 0, 0)
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/* The maximum number of peelings of a single loop that is peeled completely. */
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DEFPARAM(PARAM_MAX_COMPLETELY_PEEL_TIMES,
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"max-completely-peel-times",
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"The maximum number of peelings of a single loop that is peeled completely",
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16, 0, 0)
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/* The maximum number of insns of a peeled loop that rolls only once. */
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DEFPARAM(PARAM_MAX_ONCE_PEELED_INSNS,
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"max-once-peeled-insns",
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"The maximum number of insns of a peeled loop that rolls only once",
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400, 0, 0)
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/* The maximum number of insns of an unswitched loop. */
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DEFPARAM(PARAM_MAX_UNSWITCH_INSNS,
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"max-unswitch-insns",
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"The maximum number of insns of an unswitched loop",
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50, 0, 0)
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/* The maximum level of recursion in unswitch_single_loop. */
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DEFPARAM(PARAM_MAX_UNSWITCH_LEVEL,
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"max-unswitch-level",
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"The maximum number of unswitchings in a single loop",
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3, 0, 0)
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/* The maximum number of iterations of a loop the brute force algorithm
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for analysis of # of iterations of the loop tries to evaluate. */
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DEFPARAM(PARAM_MAX_ITERATIONS_TO_TRACK,
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"max-iterations-to-track",
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"Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates",
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1000, 0, 0)
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/* A cutoff to avoid costly computations of the number of iterations in
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the doloop transformation. */
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DEFPARAM(PARAM_MAX_ITERATIONS_COMPUTATION_COST,
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"max-iterations-computation-cost",
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"Bound on the cost of an expression to compute the number of iterations",
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10, 0, 0)
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DEFPARAM(PARAM_MAX_SMS_LOOP_NUMBER,
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"max-sms-loop-number",
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"Maximum number of loops to perform swing modulo scheduling on (mainly for debugging)",
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-1, -1, -1)
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/* This parameter is used to tune SMS MAX II calculations. */
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DEFPARAM(PARAM_SMS_MAX_II_FACTOR,
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"sms-max-ii-factor",
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"A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop",
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100, 0, 0)
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DEFPARAM(PARAM_SMS_DFA_HISTORY,
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"sms-dfa-history",
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"The number of cycles the swing modulo scheduler considers when checking conflicts using DFA",
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0, 0, 0)
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DEFPARAM(PARAM_SMS_LOOP_AVERAGE_COUNT_THRESHOLD,
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"sms-loop-average-count-threshold",
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"A threshold on the average loop count considered by the swing modulo scheduler",
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0, 0, 0)
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DEFPARAM(HOT_BB_COUNT_FRACTION,
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"hot-bb-count-fraction",
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"Select fraction of the maximal count of repetitions of basic block in program given basic block needs to have to be considered hot",
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10000, 0, 0)
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DEFPARAM(HOT_BB_FREQUENCY_FRACTION,
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"hot-bb-frequency-fraction",
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"Select fraction of the maximal frequency of executions of basic block in function given basic block needs to have to be considered hot",
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1000, 0, 0)
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/* For guessed profiles, the loops having unknown number of iterations
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are predicted to iterate relatively few (10) times at average.
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For functions containing one loop with large known number of iterations
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and other loops having unbounded loops we would end up predicting all
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the other loops cold that is not usually the case. So we need to artificially
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flatten the profile.
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We need to cut the maximal predicted iterations to large enough iterations
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so the loop appears important, but safely within HOT_BB_COUNT_FRACTION
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range. */
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DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
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"max-predicted-iterations",
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"The maximum number of loop iterations we predict statically",
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100, 0, 0)
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DEFPARAM(TRACER_DYNAMIC_COVERAGE_FEEDBACK,
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"tracer-dynamic-coverage-feedback",
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"The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available",
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95, 0, 100)
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DEFPARAM(TRACER_DYNAMIC_COVERAGE,
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"tracer-dynamic-coverage",
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"The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available",
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75, 0, 100)
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DEFPARAM(TRACER_MAX_CODE_GROWTH,
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"tracer-max-code-growth",
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"Maximal code growth caused by tail duplication (in percent)",
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100, 0, 0)
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DEFPARAM(TRACER_MIN_BRANCH_RATIO,
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"tracer-min-branch-ratio",
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"Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent)",
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10, 0, 100)
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DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK,
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"tracer-min-branch-probability-feedback",
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"Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available",
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80, 0, 100)
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DEFPARAM(TRACER_MIN_BRANCH_PROBABILITY,
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"tracer-min-branch-probability",
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"Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available",
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50, 0, 100)
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/* The maximum number of incoming edges to consider for crossjumping. */
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DEFPARAM(PARAM_MAX_CROSSJUMP_EDGES,
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"max-crossjump-edges",
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"The maximum number of incoming edges to consider for crossjumping",
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100, 0, 0)
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/* The minimum number of matching instructions to consider for crossjumping. */
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DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
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"min-crossjump-insns",
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"The minimum number of matching instructions to consider for crossjumping",
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5, 0, 0)
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/* The maximum number expansion factor when copying basic blocks. */
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DEFPARAM(PARAM_MAX_GROW_COPY_BB_INSNS,
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"max-grow-copy-bb-insns",
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"The maximum expansion factor when copying basic blocks",
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8, 0, 0)
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/* The maximum number of insns to duplicate when unfactoring computed gotos. */
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DEFPARAM(PARAM_MAX_GOTO_DUPLICATION_INSNS,
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"max-goto-duplication-insns",
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"The maximum number of insns to duplicate when unfactoring computed gotos",
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8, 0, 0)
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/* The maximum length of path considered in cse. */
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DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
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"max-cse-path-length",
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"The maximum length of path considered in cse",
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10, 0, 0)
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DEFPARAM(PARAM_MAX_CSE_INSNS,
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"max-cse-insns",
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"The maximum instructions CSE process before flushing",
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1000, 0, 0)
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/* The cost of expression in loop invariant motion that is considered
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expensive. */
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DEFPARAM(PARAM_LIM_EXPENSIVE,
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"lim-expensive",
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"The minimum cost of an expensive expression in the loop invariant motion",
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20, 0, 0)
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/* Bound on number of candidates for induction variables below that
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all candidates are considered for each use in induction variable
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optimizations. */
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DEFPARAM(PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND,
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"iv-consider-all-candidates-bound",
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"Bound on number of candidates below that all candidates are considered in iv optimizations",
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30, 0, 0)
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/* The induction variable optimizations give up on loops that contain more
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induction variable uses. */
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DEFPARAM(PARAM_IV_MAX_CONSIDERED_USES,
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"iv-max-considered-uses",
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"Bound on number of iv uses in loop optimized in iv optimizations",
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250, 0, 0)
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/* If there are at most this number of ivs in the set, try removing unnecessary
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ivs from the set always. */
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DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
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"iv-always-prune-cand-set-bound",
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"If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization",
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10, 0, 0)
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DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
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"scev-max-expr-size",
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"Bound on size of expressions used in the scalar evolutions analyzer",
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20, 0, 0)
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DEFPARAM(PARAM_VECT_MAX_VERSION_CHECKS,
|
|
"vect-max-version-checks",
|
|
"Bound on number of runtime checks inserted by the vectorizer's loop versioning",
|
|
6, 0, 0)
|
|
|
|
/* The product of the next two is used to decide whether or not to
|
|
use .GLOBAL_VAR. See tree-dfa.c. */
|
|
DEFPARAM(PARAM_GLOBAL_VAR_THRESHOLD,
|
|
"global-var-threshold",
|
|
"Given N calls and V call-clobbered vars in a function. Use .GLOBAL_VAR if NxV is larger than this limit",
|
|
500000, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_CSELIB_MEMORY_LOCATIONS,
|
|
"max-cselib-memory-locations",
|
|
"The maximum memory locations recorded by cselib",
|
|
500, 0, 0)
|
|
DEFPARAM(PARAM_MAX_FLOW_MEMORY_LOCATIONS,
|
|
"max-flow-memory-locations",
|
|
"The maximum memory locations recorded by flow",
|
|
100, 0, 0)
|
|
|
|
#ifdef ENABLE_GC_ALWAYS_COLLECT
|
|
# define GGC_MIN_EXPAND_DEFAULT 0
|
|
# define GGC_MIN_HEAPSIZE_DEFAULT 0
|
|
#else
|
|
# define GGC_MIN_EXPAND_DEFAULT 30
|
|
# define GGC_MIN_HEAPSIZE_DEFAULT 4096
|
|
#endif
|
|
|
|
DEFPARAM(GGC_MIN_EXPAND,
|
|
"ggc-min-expand",
|
|
"Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap",
|
|
GGC_MIN_EXPAND_DEFAULT, 0, 0)
|
|
|
|
DEFPARAM(GGC_MIN_HEAPSIZE,
|
|
"ggc-min-heapsize",
|
|
"Minimum heap size before we start collecting garbage, in kilobytes",
|
|
GGC_MIN_HEAPSIZE_DEFAULT, 0, 0)
|
|
|
|
#undef GGC_MIN_EXPAND_DEFAULT
|
|
#undef GGC_MIN_HEAPSIZE_DEFAULT
|
|
|
|
DEFPARAM(PARAM_MAX_RELOAD_SEARCH_INSNS,
|
|
"max-reload-search-insns",
|
|
"The maximum number of instructions to search backward when looking for equivalent reload",
|
|
100, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_ALIASED_VOPS,
|
|
"max-aliased-vops",
|
|
"The maximum number of virtual operands allowed to represent aliases before triggering alias grouping",
|
|
500, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_SCHED_REGION_BLOCKS,
|
|
"max-sched-region-blocks",
|
|
"The maximum number of blocks in a region to be considered for interblock scheduling",
|
|
10, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_SCHED_REGION_INSNS,
|
|
"max-sched-region-insns",
|
|
"The maximum number of insns in a region to be considered for interblock scheduling",
|
|
100, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MIN_SPEC_PROB,
|
|
"min-spec-prob",
|
|
"The minimum probability of reaching a source block for interblock speculative scheduling",
|
|
40, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_SCHED_EXTEND_REGIONS_ITERS,
|
|
"max-sched-extend-regions-iters",
|
|
"The maximum number of iterations through CFG to extend regions",
|
|
0, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_SCHED_INSN_CONFLICT_DELAY,
|
|
"max-sched-insn-conflict-delay",
|
|
"The maximum conflict delay for an insn to be considered for speculative motion",
|
|
3, 1, 10)
|
|
|
|
DEFPARAM(PARAM_SCHED_SPEC_PROB_CUTOFF,
|
|
"sched-spec-prob-cutoff",
|
|
"The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.",
|
|
40, 0, 100)
|
|
|
|
DEFPARAM(PARAM_MAX_LAST_VALUE_RTL,
|
|
"max-last-value-rtl",
|
|
"The maximum number of RTL nodes that can be recorded as combiner's last value",
|
|
10000, 0, 0)
|
|
|
|
/* INTEGER_CST nodes are shared for values [{-1,0} .. N) for
|
|
{signed,unsigned} integral types. This determines N.
|
|
Experimentation shows 256 to be a good value. */
|
|
DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
|
|
"integer-share-limit",
|
|
"The upper bound for sharing integer constants",
|
|
256, 2, 2)
|
|
|
|
/* Incremental SSA updates for virtual operands may be very slow if
|
|
there is a large number of mappings to process. In those cases, it
|
|
is faster to rewrite the virtual symbols from scratch as if they
|
|
had been recently introduced. This heuristic cannot be applied to
|
|
SSA mappings for real SSA names, only symbols kept in FUD chains.
|
|
|
|
PARAM_MIN_VIRTUAL_MAPPINGS specifies the minimum number of virtual
|
|
mappings that should be registered to trigger the heuristic.
|
|
|
|
PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO specifies the ratio between
|
|
mappings and symbols. If the number of virtual mappings is
|
|
PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO bigger than the number of
|
|
virtual symbols to be updated, then the updater switches to a full
|
|
update for those symbols. */
|
|
DEFPARAM (PARAM_MIN_VIRTUAL_MAPPINGS,
|
|
"min-virtual-mappings",
|
|
"Minimum number of virtual mappings to consider switching to full virtual renames",
|
|
100, 0, 0)
|
|
|
|
DEFPARAM (PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO,
|
|
"virtual-mappings-ratio",
|
|
"Ratio between virtual mappings and virtual symbols to do full virtual renames",
|
|
3, 0, 0)
|
|
|
|
DEFPARAM (PARAM_SSP_BUFFER_SIZE,
|
|
"ssp-buffer-size",
|
|
"The lower bound for a buffer to be considered for stack smashing protection",
|
|
8, 1, 0)
|
|
|
|
/* When we thread through a block we have to make copies of the
|
|
statements within the block. Clearly for large blocks the code
|
|
duplication is bad.
|
|
|
|
PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS specifies the maximum number
|
|
of statements and PHI nodes allowed in a block which is going to
|
|
be duplicated for thread jumping purposes.
|
|
|
|
Some simple analysis showed that more than 99% of the jump
|
|
threading opportunities are for blocks with less than 15
|
|
statements. So we can get the benefits of jump threading
|
|
without excessive code bloat for pathological cases with the
|
|
throttle set at 15 statements. */
|
|
DEFPARAM (PARAM_MAX_JUMP_THREAD_DUPLICATION_STMTS,
|
|
"max-jump-thread-duplication-stmts",
|
|
"Maximum number of statements allowed in a block that needs to be duplicated when threading jumps",
|
|
15, 0, 0)
|
|
|
|
/* This is the maximum number of fields a variable may have before the pointer analysis machinery
|
|
will stop trying to treat it in a field-sensitive manner.
|
|
There are programs out there with thousands of fields per structure, and handling them
|
|
field-sensitively is not worth the cost. */
|
|
DEFPARAM (PARAM_MAX_FIELDS_FOR_FIELD_SENSITIVE,
|
|
"max-fields-for-field-sensitive",
|
|
"Maximum number of fields in a structure before pointer analysis treats the structure as a single variable",
|
|
100, 0, 0)
|
|
|
|
DEFPARAM(PARAM_MAX_SCHED_READY_INSNS,
|
|
"max-sched-ready-insns",
|
|
"The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass",
|
|
100, 0, 0)
|
|
|
|
/*
|
|
Local variables:
|
|
mode:c
|
|
End: */
|