path: root/gcc/params.opt

; Parameter options of the compiler.

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; This file is part of GCC.
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; See the GCC internals manual (options.texi) for a description of this file's format.

; Please try to keep this file in ASCII collating order.

-param=align-loop-iterations=
Common Joined UInteger Var(param_align_loop_iterations) Init(4) Param Optimization
Loops iterating at least selected number of iterations will get loop alignment.

-param=align-threshold=
Common Joined UInteger Var(param_align_threshold) Init(100) IntegerRange(1, 65536) Param Optimization
Select fraction of the maximal frequency of executions of basic block in function given basic block get alignment.

-param=asan-globals=
Common Joined UInteger Var(param_asan_globals) Init(1) IntegerRange(0, 1) Param
Enable asan globals protection.

-param=asan-instrument-allocas=
Common Joined UInteger Var(param_asan_protect_allocas) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan allocas/VLAs protection.

-param=asan-instrument-reads=
Common Joined UInteger Var(param_asan_instrument_reads) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan load operations protection.

-param=asan-instrument-writes=
Common Joined UInteger Var(param_asan_instrument_writes) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan store operations protection.

-param=asan-instrumentation-with-call-threshold=
Common Joined UInteger Var(param_asan_instrumentation_with_call_threshold) Init(7000) Param Optimization
Use callbacks instead of inline code if number of accesses in function becomes greater or equal to this number.

-param=asan-memintrin=
Common Joined UInteger Var(param_asan_memintrin) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan builtin functions protection.

-param=asan-stack=
Common Joined UInteger Var(param_asan_stack) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan stack protection.

-param=asan-use-after-return=
Common Joined UInteger Var(param_asan_use_after_return) Init(1) IntegerRange(0, 1) Param Optimization
Enable asan detection of use-after-return bugs.

-param=avg-loop-niter=
Common Joined UInteger Var(param_avg_loop_niter) Init(10) IntegerRange(1, 65536) Param Optimization
Average number of iterations of a loop.

-param=avoid-fma-max-bits=
Common Joined UInteger Var(param_avoid_fma_max_bits) IntegerRange(0, 512) Param Optimization
Maximum number of bits for which we avoid creating FMAs.

-param=builtin-expect-probability=
Common Joined UInteger Var(param_builtin_expect_probability) Init(90) IntegerRange(0, 100) Param Optimization
Set the estimated probability in percentage for builtin expect. The default value is 90% probability.

-param=builtin-string-cmp-inline-length=
Common Joined UInteger Var(param_builtin_string_cmp_inline_length) Init(3) IntegerRange(0, 100) Param Optimization
The maximum length of a constant string for a builtin string cmp call eligible for inlining. The default value is 3.

-param=case-values-threshold=
Common Joined UInteger Var(param_case_values_threshold) Param Optimization
The smallest number of different values for which it is best to use a jump-table instead of a tree of conditional branches, if 0, use the default for the machine.

-param=comdat-sharing-probability=
Common Joined UInteger Var(param_comdat_sharing_probability) Init(20) Param Optimization
Probability that COMDAT function will be shared with different compilation unit.

-param=cxx-max-namespaces-for-diagnostic-help=
Common Joined UInteger Var(param_cxx_max_namespaces_for_diagnostic_help) Init(1000) Param
Maximum number of namespaces to search for alternatives when name lookup fails.

-param=dse-max-alias-queries-per-store=
Common Joined UInteger Var(param_dse_max_alias_queries_per_store) Init(256) Param Optimization
Maximum number of queries into the alias oracle per store.

-param=dse-max-object-size=
Common Joined UInteger Var(param_dse_max_object_size) Init(256) Param Optimization
Maximum size (in bytes) of objects tracked bytewise by dead store elimination.

-param=early-inlining-insns=
Common Joined UInteger Var(param_early_inlining_insns) Init(6) Optimization Param
Maximal estimated growth of function body caused by early inlining of single call.

-param=fsm-maximum-phi-arguments=
Common Joined UInteger Var(param_fsm_maximum_phi_arguments) Init(100) IntegerRange(1, 999999) Param Optimization
Maximum number of arguments a PHI may have before the FSM threader will not try to thread through its block.

-param=fsm-scale-path-blocks=
Common Joined UInteger Var(param_fsm_scale_path_blocks) Init(3) IntegerRange(1, 10) Param Optimization
Scale factor to apply to the number of blocks in a threading path when comparing to the number of (scaled) statements.

-param=fsm-scale-path-stmts=
Common Joined UInteger Var(param_fsm_scale_path_stmts) Init(2) IntegerRange(1, 10) Param Optimization
Scale factor to apply to the number of statements in a threading path when comparing to the number of (scaled) blocks.

-param=gcse-after-reload-critical-fraction=
Common Joined UInteger Var(param_gcse_after_reload_critical_fraction) Init(10) Param Optimization
The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload.

-param=gcse-after-reload-partial-fraction=
Common Joined UInteger Var(param_gcse_after_reload_partial_fraction) Init(3) Param Optimization
The threshold ratio for performing partial redundancy elimination after reload.

-param=gcse-cost-distance-ratio=
Common Joined UInteger Var(param_gcse_cost_distance_ratio) Init(10) Param Optimization
Scaling factor in calculation of maximum distance an expression can be moved by GCSE optimizations.

-param=gcse-unrestricted-cost=
Common Joined UInteger Var(param_gcse_unrestricted_cost) Init(3) Param Optimization
Cost at which GCSE optimizations will not constraint the distance an expression can travel.

-param=ggc-min-expand=
Common Joined UInteger Var(param_ggc_min_expand) Init(30) Param
Minimum heap expansion to trigger garbage collection, as a percentage of the total size of the heap.

-param=ggc-min-heapsize=
Common Joined UInteger Var(param_ggc_min_heapsize) Init(4096) Param
Minimum heap size before we start collecting garbage, in kilobytes.

-param=gimple-fe-computed-hot-bb-threshold=
Common Joined UInteger Var(param_gimple_fe_computed_hot_bb_threshold) Param
The number of executions of a basic block which is considered hot. The parameter is used only in GIMPLE FE.

-param=graphite-allow-codegen-errors=
Common Joined UInteger Var(param_graphite_allow_codegen_errors) IntegerRange(0, 1) Param
Whether codegen errors should be ICEs when -fchecking.

-param=graphite-max-arrays-per-scop=
Common Joined UInteger Var(param_graphite_max_arrays_per_scop) Init(100) Param Optimization
Maximum number of arrays per SCoP.

-param=graphite-max-nb-scop-params=
Common Joined UInteger Var(param_graphite_max_nb_scop_params) Init(10) Param Optimization
Maximum number of parameters in a SCoP.

-param=hash-table-verification-limit=
Common Joined UInteger Var(param_hash_table_verification_limit) Init(10) Param
The number of elements for which hash table verification is done for each searched element.

-param=hot-bb-count-fraction=
Common Joined UInteger Var(param_hot_bb_count_fraction) Init(10000) Param
The denominator n of fraction 1/n of the maximal execution count of a basic block in the entire program that a basic block needs to at least have in order to be considered hot (used in non-LTO mode).

-param=hot-bb-count-ws-permille=
Common Joined UInteger Var(param_hot_bb_count_ws_permille) Init(990) IntegerRange(0, 1000) Param
The number of most executed permilles of the profiled execution of the entire program to which the execution count of a basic block must be part of in order to be considered hot (used in LTO mode).

-param=hot-bb-frequency-fraction=
Common Joined UInteger Var(param_hot_bb_frequency_fraction) Init(1000) Param
The denominator n of fraction 1/n of the execution frequency of the entry block of a function that a basic block of this function needs to at least have in order to be considered hot.

-param=hsa-gen-debug-stores=
Common Joined UInteger Var(param_hsa_gen_debug_stores) IntegerRange(0, 1) Param
Level of hsa debug stores verbosity.

-param=inline-heuristics-hint-percent=
Common Joined UInteger Var(param_inline_heuristics_hint_percent) Init(200) Optimization IntegerRange(100, 1000000) Param
The scale (in percents) applied to inline-insns-single and auto limits when heuristics hints that inlining is very profitable.

-param=inline-min-speedup=
Common Joined UInteger Var(param_inline_min_speedup) Init(30) Optimization IntegerRange(0, 100) Param
The minimal estimated speedup allowing inliner to ignore inline-insns-single and inline-insns-auto.

-param=inline-unit-growth=
Common Joined UInteger Var(param_inline_unit_growth) Init(40) Optimization Param
How much can given compilation unit grow because of the inlining (in percent).

-param=integer-share-limit=
Common Joined UInteger Var(param_integer_share_limit) Init(251) IntegerRange(2, 65536) Param
The upper bound for sharing integer constants.

-param=ipa-cp-eval-threshold=
Common Joined UInteger Var(param_ipa_cp_eval_threshold) Init(500) Param Optimization
Threshold ipa-cp opportunity evaluation that is still considered beneficial to clone.

-param=ipa-cp-loop-hint-bonus=
Common Joined UInteger Var(param_ipa_cp_loop_hint_bonus) Init(64) Param Optimization
Compile-time bonus IPA-CP assigns to candidates which make loop bounds or strides known.

-param=ipa-cp-max-recursive-depth=
Common Joined UInteger Var(param_ipa_cp_max_recursive_depth) Init(8) Param Optimization
Maximum depth of recursive cloning for self-recursive function.

-param=ipa-cp-min-recursive-probability=
Common Joined UInteger Var(param_ipa_cp_min_recursive_probability) Init(2) Param Optimization
Recursive cloning only when the probability of call being executed exceeds the parameter.

-param=ipa-cp-recursion-penalty=
Common Joined UInteger Var(param_ipa_cp_recursion_penalty) Init(40) IntegerRange(0, 100) Param Optimization
Percentage penalty the recursive functions will receive when they are evaluated for cloning.

-param=ipa-cp-single-call-penalty=
Common Joined UInteger Var(param_ipa_cp_single_call_penalty) Init(15) IntegerRange(0, 100) Param Optimization
Percentage penalty functions containing a single call to another function will receive when they are evaluated for cloning.

-param=ipa-cp-unit-growth=
Common Joined UInteger Var(param_ipa_cp_unit_growth) Init(10) Param Optimization
How much can given compilation unit grow because of the interprocedural constant propagation (in percent).

-param=ipa-cp-value-list-size=
Common Joined UInteger Var(param_ipa_cp_value_list_size) Init(8) Param Optimization
Maximum size of a list of values associated with each parameter for interprocedural constant propagation.

-param=ipa-max-aa-steps=
Common Joined UInteger Var(param_ipa_max_aa_steps) Init(25000) Param Optimization
Maximum number of statements that will be visited by IPA formal parameter analysis based on alias analysis in any given function.

-param=ipa-max-agg-items=
Common Joined UInteger Var(param_ipa_max_agg_items) Init(16) Param Optimization
Maximum number of aggregate content items for a parameter in jump functions and lattices.

-param=ipa-max-param-expr-ops=
Common Joined UInteger Var(param_ipa_max_param_expr_ops) Init(10) Param Optimization
Maximum number of operations in a parameter expression that can be handled by IPA analysis.

-param=ipa-max-switch-predicate-bounds=
Common Joined UInteger Var(param_ipa_max_switch_predicate_bounds) Init(5) Param Optimization
Maximal number of boundary endpoints of case ranges of switch statement used during IPA function summary generation.

-param=ipa-sra-max-replacements=
Common Joined UInteger Var(param_ipa_sra_max_replacements) Optimization Init(8) IntegerRange(0, 16) Param
Maximum pieces that IPA-SRA tracks per formal parameter, as a consequence, also the maximum number of replacements of a formal parameter.

-param=ipa-sra-ptr-growth-factor=
Common Joined UInteger Var(param_ipa_sra_ptr_growth_factor) Init(2) Param Optimization
Maximum allowed growth of number and total size of new parameters that ipa-sra replaces a pointer to an aggregate with.

-param=ira-loop-reserved-regs=
Common Joined UInteger Var(param_ira_loop_reserved_regs) Init(2) Param Optimization
The number of registers in each class kept unused by loop invariant motion.

-param=ira-max-conflict-table-size=
Common Joined UInteger Var(param_ira_max_conflict_table_size) Init(1000) Param Optimization
Max size of conflict table in MB.

-param=ira-max-loops-num=
Common Joined UInteger Var(param_ira_max_loops_num) Init(100) Param Optimization
Max loops number for regional RA.

-param=iv-always-prune-cand-set-bound=
Common Joined UInteger Var(param_iv_always_prune_cand_set_bound) Init(10) Param Optimization
If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization.

-param=iv-consider-all-candidates-bound=
Common Joined UInteger Var(param_iv_consider_all_candidates_bound) Init(40) Param Optimization
Bound on number of candidates below that all candidates are considered in iv optimizations.

-param=iv-max-considered-uses=
Common Joined UInteger Var(param_iv_max_considered_uses) Init(250) Param Optimization
Bound on number of iv uses in loop optimized in iv optimizations.

-param=jump-table-max-growth-ratio-for-size=
Common Joined UInteger Var(param_jump_table_max_growth_ratio_for_size) Init(300) Param Optimization
The maximum code size growth ratio when expanding into a jump table (in percent).  The parameter is used when optimizing for size.

-param=jump-table-max-growth-ratio-for-speed=
Common Joined UInteger Var(param_jump_table_max_growth_ratio_for_speed) Init(800) Param Optimization
The maximum code size growth ratio when expanding into a jump table (in percent).  The parameter is used when optimizing for speed.

-param=l1-cache-line-size=
Common Joined UInteger Var(param_l1_cache_line_size) Init(32) Param Optimization
The size of L1 cache line.

-param=l1-cache-size=
Common Joined UInteger Var(param_l1_cache_size) Init(64) Param Optimization
The size of L1 cache.

-param=l2-cache-size=
Common Joined UInteger Var(param_l2_cache_size) Init(512) Param Optimization
The size of L2 cache.

-param=large-function-growth=
Common Joined UInteger Var(param_large_function_growth) Optimization Init(100) Param
Maximal growth due to inlining of large function (in percent).

-param=large-function-insns=
Common Joined UInteger Var(param_large_function_insns) Optimization Init(2700) Param
The size of function body to be considered large.

-param=large-stack-frame=
Common Joined UInteger Var(param_large_stack_frame) Init(256) Optimization Param
The size of stack frame to be considered large.

-param=large-stack-frame-growth=
Common Joined UInteger Var(param_stack_frame_growth) Optimization Init(1000) Param
Maximal stack frame growth due to inlining (in percent).

-param=large-unit-insns=
Common Joined UInteger Var(param_large_unit_insns) Optimization Init(10000) Param
The size of translation unit to be considered large.

-param=lim-expensive=
Common Joined UInteger Var(param_lim_expensive) Init(20) Param Optimization
The minimum cost of an expensive expression in the loop invariant motion.

-param=logical-op-non-short-circuit=
Common Joined UInteger Var(param_logical_op_non_short_circuit) Init(-1) IntegerRange(-1, 1) Param
True if a non-short-circuit operation is optimal.

-param=loop-block-tile-size=
Common Joined UInteger Var(param_loop_block_tile_size) Init(51) Param Optimization
Size of tiles for loop blocking.

-param=loop-interchange-max-num-stmts=
Common Joined UInteger Var(param_loop_interchange_max_num_stmts) Init(64) Param Optimization
The maximum number of stmts in loop nest for loop interchange.

-param=loop-interchange-stride-ratio=
Common Joined UInteger Var(param_loop_interchange_stride_ratio) Init(2) Param Optimization
The minimum stride ratio for loop interchange to be profitable.

-param=loop-invariant-max-bbs-in-loop=
Common Joined UInteger Var(param_loop_invariant_max_bbs_in_loop) Init(10000) Param Optimization
Max basic blocks number in loop for loop invariant motion.

-param=loop-max-datarefs-for-datadeps=
Common Joined UInteger Var(param_loop_max_datarefs_for_datadeps) Init(1000) Param Optimization
Maximum number of datarefs in loop for building loop data dependencies.

-param=loop-versioning-max-inner-insns=
Common Joined UInteger Var(param_loop_versioning_max_inner_insns) Init(200) Param Optimization
The maximum number of instructions in an inner loop that is being considered for versioning.

-param=loop-versioning-max-outer-insns=
Common Joined UInteger Var(param_loop_versioning_max_outer_insns) Init(100) Param Optimization
The maximum number of instructions in an outer loop that is being considered for versioning, on top of the instructions in inner loops.

-param=lra-inheritance-ebb-probability-cutoff=
Common Joined UInteger Var(param_lra_inheritance_ebb_probability_cutoff) Init(40) IntegerRange(0, 100) Param Optimization
Minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA.

-param=lra-max-considered-reload-pseudos=
Common Joined UInteger Var(param_lra_max_considered_reload_pseudos) Init(500) Param Optimization
The max number of reload pseudos which are considered during spilling a non-reload pseudo.

-param=lto-max-partition=
Common Joined UInteger Var(param_max_partition_size) Init(1000000) Param
Maximal size of a partition for LTO (in estimated instructions).

-param=lto-max-streaming-parallelism=
Common Joined UInteger Var(param_max_lto_streaming_parallelism) Init(32) IntegerRange(1, 65536) Param
maximal number of LTO partitions streamed in parallel.

-param=lto-min-partition=
Common Joined UInteger Var(param_min_partition_size) Init(10000) Param
Minimal size of a partition for LTO (in estimated instructions).

-param=lto-partitions=
Common Joined UInteger Var(param_lto_partitions) Init(128) IntegerRange(1, 65536) Param
Number of partitions the program should be split to.

-param=max-average-unrolled-insns=
Common Joined UInteger Var(param_max_average_unrolled_insns) Init(80) Param Optimization
The maximum number of instructions to consider to unroll in a loop on average.

-param=max-combine-insns=
Common Joined UInteger Var(param_max_combine_insns) Init(4) IntegerRange(2, 4) Param Optimization
The maximum number of insns combine tries to combine.

-param=max-completely-peel-loop-nest-depth=
Common Joined UInteger Var(param_max_unroll_iterations) Init(8) Param Optimization
The maximum depth of a loop nest we completely peel.

-param=max-completely-peel-times=
Common Joined UInteger Var(param_max_completely_peel_times) Init(16) Param Optimization
The maximum number of peelings of a single loop that is peeled completely.

-param=max-completely-peeled-insns=
Common Joined UInteger Var(param_max_completely_peeled_insns) Init(200) Param Optimization
The maximum number of insns of a completely peeled loop.

-param=max-crossjump-edges=
Common Joined UInteger Var(param_max_crossjump_edges) Init(100) Param Optimization
The maximum number of incoming edges to consider for crossjumping.

-param=max-cse-insns=
Common Joined UInteger Var(param_max_cse_insns) Init(1000) Param Optimization
The maximum instructions CSE process before flushing.

-param=max-cse-path-length=
Common Joined UInteger Var(param_max_cse_path_length) Init(10) IntegerRange(1, 65536) Param Optimization
The maximum length of path considered in cse.

-param=max-cselib-memory-locations=
Common Joined UInteger Var(param_max_cselib_memory_locations) Init(500) Param Optimization
The maximum memory locations recorded by cselib.

-param=max-debug-marker-count=
Common Joined UInteger Var(param_max_debug_marker_count) Init(100000) Param Optimization
Max. count of debug markers to expand or inline.

-param=max-delay-slot-insn-search=
Common Joined UInteger Var(param_max_delay_slot_insn_search) Init(100) Param Optimization
The maximum number of instructions to consider to fill a delay slot.

-param=max-delay-slot-live-search=
Common Joined UInteger Var(param_max_delay_slot_live_search) Init(333) Param Optimization
The maximum number of instructions to consider to find accurate live register information.

-param=max-dse-active-local-stores=
Common Joined UInteger Var(param_max_dse_active_local_stores) Init(5000) Param Optimization
Maximum number of active local stores in RTL dead store elimination.

-param=max-early-inliner-iterations=
Common Joined UInteger Var(param_early_inliner_max_iterations) Init(1) Param Optimization
The maximum number of nested indirect inlining performed by early inliner.

-param=max-fields-for-field-sensitive=
Common Joined UInteger Var(param_max_fields_for_field_sensitive) Param
Maximum number of fields in a structure before pointer analysis treats the structure as a single variable.

-param=max-fsm-thread-length=
Common Joined UInteger Var(param_max_fsm_thread_length) Init(10) IntegerRange(1, 999999) Param Optimization
Maximum number of basic blocks on a finite state automaton jump thread path.

-param=max-fsm-thread-path-insns=
Common Joined UInteger Var(param_max_fsm_thread_path_insns) Init(100) IntegerRange(1, 999999) Param Optimization
Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path.

-param=max-fsm-thread-paths=
Common Joined UInteger Var(param_max_fsm_thread_paths) Init(50) IntegerRange(1, 999999) Param Optimization
Maximum number of new jump thread paths to create for a finite state automaton.

-param=max-gcse-insertion-ratio=
Common Joined UInteger Var(param_max_gcse_insertion_ratio) Init(20) Param Optimization
The maximum ratio of insertions to deletions of expressions in GCSE.

-param=max-gcse-memory=
Common Joined UInteger Var(param_max_gcse_memory) Init(134217728) Param Optimization
The maximum amount of memory to be allocated by GCSE.

-param=max-goto-duplication-insns=
Common Joined UInteger Var(param_max_goto_duplication_insns) Init(8) Param Optimization
The maximum number of insns to duplicate when unfactoring computed gotos.

-param=max-grow-copy-bb-insns=
Common Joined UInteger Var(param_max_grow_copy_bb_insns) Init(8) Param Optimization
The maximum expansion factor when copying basic blocks.

-param=max-hoist-depth=
Common Joined UInteger Var(param_max_hoist_depth) Init(30) Param Optimization
Maximum depth of search in the dominator tree for expressions to hoist.

-param=max-inline-insns-auto=
Common Joined UInteger Var(param_max_inline_insns_auto) Init(15) Optimization Param
The maximum number of instructions when automatically inlining.

-param=max-inline-insns-recursive=
Common Joined UInteger Var(param_max_inline_insns_recursive) Optimization Init(450) Param
The maximum number of instructions inline function can grow to via recursive inlining.

-param=max-inline-insns-recursive-auto=
Common Joined UInteger Var(param_max_inline_insns_recursive_auto) Optimization Init(450) Param
The maximum number of instructions non-inline function can grow to via recursive inlining.

-param=max-inline-insns-single=
Common Joined UInteger Var(param_max_inline_insns_single) Optimization Init(70) Param
The maximum number of instructions in a single function eligible for inlining.

-param=max-inline-insns-size=
Common Joined UInteger Var(param_max_inline_insns_size) Optimization Param
The maximum number of instructions when inlining for size.

-param=max-inline-insns-small=
Common Joined UInteger Var(param_max_inline_insns_small) Optimization Param
The maximum number of instructions when automatically inlining small functions.

-param=max-inline-recursive-depth=
Common Joined UInteger Var(param_max_inline_recursive_depth) Optimization Init(8) Param
The maximum depth of recursive inlining for inline functions.

-param=max-inline-recursive-depth-auto=
Common Joined UInteger Var(param_max_inline_recursive_depth_auto) Optimization Init(8) Param
The maximum depth of recursive inlining for non-inline functions.

-param=max-isl-operations=
Common Joined UInteger Var(param_max_isl_operations) Init(350000) Param Optimization
Maximum number of isl operations, 0 means unlimited.

-param=max-iterations-computation-cost=
Common Joined UInteger Var(param_max_iterations_computation_cost) Init(10) Param Optimization
Bound on the cost of an expression to compute the number of iterations.

-param=max-iterations-to-track=
Common Joined UInteger Var(param_max_iterations_to_track) Init(1000) Param Optimization
Bound on the number of iterations the brute force # of iterations analysis algorithm evaluates.

-param=max-jump-thread-duplication-stmts=
Common Joined UInteger Var(param_max_jump_thread_duplication_stmts) Init(15) Param Optimization
Maximum number of statements allowed in a block that needs to be duplicated when threading jumps.

-param=max-last-value-rtl=
Common Joined UInteger Var(param_max_last_value_rtl) Init(10000) Param Optimization
The maximum number of RTL nodes that can be recorded as combiner's last value.

-param=max-loop-header-insns=
Common Joined UInteger Var(param_max_loop_header_insns) Init(20) Param Optimization
The maximum number of insns in loop header duplicated by the copy loop headers pass.

-param=max-modulo-backtrack-attempts=
Common Joined UInteger Var(param_max_modulo_backtrack_attempts) Init(40) Param Optimization
The maximum number of backtrack attempts the scheduler should make when modulo scheduling a loop.

-param=max-partial-antic-length=
Common Joined UInteger Var(param_max_partial_antic_length) Init(100) Param Optimization
Maximum length of partial antic set when performing tree pre optimization.

-param=max-peel-branches=
Common Joined UInteger Var(param_max_peel_branches) Init(32) Param Optimization
The maximum number of branches on the path through the peeled sequence.

-param=max-peel-times=
Common Joined UInteger Var(param_max_peel_times) Init(16) Param Optimization
The maximum number of peelings of a single loop.

-param=max-peeled-insns=
Common Joined UInteger Var(param_max_peeled_insns) Init(100) Param Optimization
The maximum number of insns of a peeled loop.

-param=max-pending-list-length=
Common Joined UInteger Var(param_max_pending_list_length) Init(32) Param Optimization
The maximum length of scheduling's pending operations list.

-param=max-pipeline-region-blocks=
Common Joined UInteger Var(param_max_pipeline_region_blocks) Init(15) Param Optimization
The maximum number of blocks in a region to be considered for interblock scheduling.

-param=max-pipeline-region-insns=
Common Joined UInteger Var(param_max_pipeline_region_insns) Init(200) Param Optimization
The maximum number of insns in a region to be considered for interblock scheduling.

-param=max-pow-sqrt-depth=
Common Joined UInteger Var(param_max_pow_sqrt_depth) Init(5) IntegerRange(1, 32) Param Optimization
Maximum depth of sqrt chains to use when synthesizing exponentiation by a real constant.

-param=max-predicted-iterations=
Common Joined UInteger Var(param_max_predicted_iterations) Init(100) IntegerRange(0, 65536) Param Optimization
The maximum number of loop iterations we predict statically.

-param=max-reload-search-insns=
Common Joined UInteger Var(param_max_reload_search_insns) Init(100) Param Optimization
The maximum number of instructions to search backward when looking for equivalent reload.

-param=max-rtl-if-conversion-insns=
Common Joined UInteger Var(param_max_rtl_if_conversion_insns) Init(10) IntegerRange(0, 99) Param Optimization
Maximum number of insns in a basic block to consider for RTL if-conversion.

-param=max-rtl-if-conversion-predictable-cost=
Common Joined UInteger Var(param_max_rtl_if_conversion_predictable_cost) Init(20) IntegerRange(0, 200) Param Optimization
Maximum permissible cost for the sequence that would be generated by the RTL if-conversion pass for a branch that is considered predictable.

-param=max-rtl-if-conversion-unpredictable-cost=
Common Joined UInteger Var(param_max_rtl_if_conversion_unpredictable_cost) Init(40) IntegerRange(0, 200) Param Optimization
Maximum permissible cost for the sequence that would be generated by the RTL if-conversion pass for a branch that is considered unpredictable.

-param=max-sched-extend-regions-iters=
Common Joined UInteger Var(param_max_sched_extend_regions_iters) Param Optimization
The maximum number of iterations through CFG to extend regions.

-param=max-sched-insn-conflict-delay=
Common Joined UInteger Var(param_max_sched_insn_conflict_delay) Init(3) IntegerRange(1, 10) Param Optimization
The maximum conflict delay for an insn to be considered for speculative motion.

-param=max-sched-ready-insns=
Common Joined UInteger Var(param_max_sched_ready_insns) Init(100) IntegerRange(1, 65536) Param Optimization
The maximum number of instructions ready to be issued to be considered by the scheduler during the first scheduling pass.

-param=max-sched-region-blocks=
Common Joined UInteger Var(param_max_sched_region_blocks) Init(10) Param Optimization
The maximum number of blocks in a region to be considered for interblock scheduling.

-param=max-sched-region-insns=
Common Joined UInteger Var(param_max_sched_region_insns) Init(100) Param Optimization
The maximum number of insns in a region to be considered for interblock scheduling.

-param=max-slsr-cand-scan=
Common Joined UInteger Var(param_max_slsr_candidate_scan) Init(50) IntegerRange(1, 999999) Param Optimization
Maximum length of candidate scans for straight-line strength reduction.

-param=max-speculative-devirt-maydefs=
Common Joined UInteger Var(param_max_speculative_devirt_maydefs) Init(50) Param Optimization
Maximum number of may-defs visited when devirtualizing speculatively.

-param=max-ssa-name-query-depth=
Common Joined UInteger Var(param_max_ssa_name_query_depth) Init(3) IntegerRange(1, 10) Param
Maximum recursion depth allowed when querying a property of an SSA name.

-param=max-stores-to-merge=
Common Joined UInteger Var(param_max_stores_to_merge) Init(64) IntegerRange(2, 65536) Param Optimization
Maximum number of constant stores to merge in the store merging pass.

-param=max-stores-to-sink=
Common Joined UInteger Var(param_max_stores_to_sink) Init(2) Param Optimization
Maximum number of conditional store pairs that can be sunk.

-param=max-tail-merge-comparisons=
Common Joined UInteger Var(param_max_tail_merge_comparisons) Init(10) Param Optimization
Maximum amount of similar bbs to compare a bb with.

-param=max-tail-merge-iterations=
Common Joined UInteger Var(param_max_tail_merge_iterations) Init(2) Param Optimization
Maximum amount of iterations of the pass over a function.

-param=max-tracked-strlens=
Common Joined UInteger Var(param_max_tracked_strlens) Init(10000) Param Optimization
Maximum number of strings for which strlen optimization pass will track string lengths.

-param=max-tree-if-conversion-phi-args=
Common Joined UInteger Var(param_max_tree_if_conversion_phi_args) Init(4) IntegerRange(2, 65536) Param Optimization
Maximum number of arguments in a PHI supported by TREE if-conversion unless the loop is marked with simd pragma.

-param=max-unroll-times=
Common Joined UInteger Var(param_max_unroll_times) Init(8) Param Optimization
The maximum number of unrollings of a single loop.

-param=max-unrolled-insns=
Common Joined UInteger Var(param_max_unrolled_insns) Init(200) Param Optimization
The maximum number of instructions to consider to unroll in a loop.

-param=max-unswitch-insns=
Common Joined UInteger Var(param_max_unswitch_insns) Init(50) Param Optimization
The maximum number of insns of an unswitched loop.

-param=max-unswitch-level=
Common Joined UInteger Var(param_max_unswitch_level) Init(3) Param Optimization
The maximum number of unswitchings in a single loop.

-param=max-variable-expansions-in-unroller=
Common Joined UInteger Var(param_max_variable_expansions) Init(1) Param Optimization
If -fvariable-expansion-in-unroller is used, the maximum number of times that an individual variable will be expanded during loop unrolling.

-param=max-vartrack-expr-depth=
Common Joined UInteger Var(param_max_vartrack_expr_depth) Init(12) Param Optimization
Max. recursion depth for expanding var tracking expressions.

-param=max-vartrack-reverse-op-size=
Common Joined UInteger Var(param_max_vartrack_reverse_op_size) Init(50) Param Optimization
Max. size of loc list for which reverse ops should be added.

-param=max-vartrack-size=
Common Joined UInteger Var(param_max_vartrack_size) Init(50000000) Param Optimization
Max. size of var tracking hash tables.

-param=max-find-base-term-values=
Common Joined UInteger Var(param_max_find_base_term_values) Init(200) Param Optimization
Maximum number of VALUEs handled during a single find_base_term call.

-param=max-vrp-switch-assertions=
Common Joined UInteger Var(param_max_vrp_switch_assertions) Init(10) Param Optimization
Maximum number of assertions to add along the default edge of a switch statement during VRP.

-param=min-crossjump-insns=
Common Joined UInteger Var(param_min_crossjump_insns) Init(5) IntegerRange(1, 65536) Param Optimization
The minimum number of matching instructions to consider for crossjumping.

-param=min-inline-recursive-probability=
Common Joined UInteger Var(param_min_inline_recursive_probability) Init(10) Optimization Param
Inline recursively only when the probability of call being executed exceeds the parameter.

-param=min-insn-to-prefetch-ratio=
Common Joined UInteger Var(param_min_insn_to_prefetch_ratio) Init(9) Param Optimization
Min. ratio of insns to prefetches to enable prefetching for a loop with an unknown trip count.

-param=min-loop-cond-split-prob=
Common Joined UInteger Var(param_min_loop_cond_split_prob) Init(30) IntegerRange(0, 100) Param Optimization
The minimum threshold for probability of semi-invariant condition statement to trigger loop split.

-param=min-nondebug-insn-uid=
Common Joined UInteger Var(param_min_nondebug_insn_uid) Param
The minimum UID to be used for a nondebug insn.

-param=min-size-for-stack-sharing=
Common Joined UInteger Var(param_min_size_for_stack_sharing) Init(32) Param Optimization
The minimum size of variables taking part in stack slot sharing when not optimizing.

-param=min-spec-prob=
Common Joined UInteger Var(param_min_spec_prob) Init(40) Param Optimization
The minimum probability of reaching a source block for interblock speculative scheduling.

-param=min-vect-loop-bound=
Common Joined UInteger Var(param_min_vect_loop_bound) Param Optimization
If -ftree-vectorize is used, the minimal loop bound of a loop to be considered for vectorization.

-param=parloops-chunk-size=
Common Joined UInteger Var(param_parloops_chunk_size) Param Optimization
Chunk size of omp schedule for loops parallelized by parloops.

-param=parloops-min-per-thread=
Common Joined UInteger Var(param_parloops_min_per_thread) Init(100) IntegerRange(2, 65536) Param Optimization
Minimum number of iterations per thread of an innermost parallelized loop.

-param=parloops-schedule=
Common Joined Var(param_parloops_schedule) Enum(parloops_schedule_type) Param Optimization
--param=parloops-schedule=[static|dynamic|guided|auto|runtime]	Schedule type of omp schedule for loops parallelized by parloops.

Enum
Name(parloops_schedule_type) Type(int)

EnumValue
Enum(parloops_schedule_type) String(static) Value(PARLOOPS_SCHEDULE_STATIC)

EnumValue
Enum(parloops_schedule_type) String(dynamic) Value(PARLOOPS_SCHEDULE_DYNAMIC)

EnumValue
Enum(parloops_schedule_type) String(guided) Value(PARLOOPS_SCHEDULE_GUIDED)

EnumValue
Enum(parloops_schedule_type) String(auto) Value(PARLOOPS_SCHEDULE_AUTO)

EnumValue
Enum(parloops_schedule_type) String(runtime) Value(PARLOOPS_SCHEDULE_RUNTIME)

-param=partial-inlining-entry-probability=
Common Joined UInteger Var(param_partial_inlining_entry_probability) Init(70) Optimization IntegerRange(0, 100) Param
Maximum probability of the entry BB of split region (in percent relative to entry BB of the function) to make partial inlining happen.

-param=predictable-branch-outcome=
Common Joined UInteger Var(param_predictable_branch_outcome) Init(2) IntegerRange(0, 50) Param Optimization
Maximal estimated outcome of branch considered predictable.

-param=prefetch-dynamic-strides=
Common Joined UInteger Var(param_prefetch_dynamic_strides) Init(1) IntegerRange(0, 1) Param Optimization
Whether software prefetch hints should be issued for non-constant strides.

-param=prefetch-latency=
Common Joined UInteger Var(param_prefetch_latency) Init(200) Param Optimization
The number of insns executed before prefetch is completed.

-param=prefetch-min-insn-to-mem-ratio=
Common Joined UInteger Var(param_prefetch_min_insn_to_mem_ratio) Init(3) Param Optimization
Min. ratio of insns to mem ops to enable prefetching in a loop.

-param=prefetch-minimum-stride=
Common Joined UInteger Var(param_prefetch_minimum_stride) Init(-1) Param Optimization
The minimum constant stride beyond which we should use prefetch hints for.

-param=profile-func-internal-id=
Common Joined UInteger Var(param_profile_func_internal_id) IntegerRange(0, 1) Param
Use internal function id in profile lookup.

-param=rpo-vn-max-loop-depth=
Common Joined UInteger Var(param_rpo_vn_max_loop_depth) Init(7) IntegerRange(2, 65536) Param Optimization
Maximum depth of a loop nest to fully value-number optimistically.

-param=sccvn-max-alias-queries-per-access=
Common Joined UInteger Var(param_sccvn_max_alias_queries_per_access) Init(1000) Param Optimization
Maximum number of disambiguations to perform per memory access.

-param=scev-max-expr-complexity=
Common Joined UInteger Var(param_scev_max_expr_complexity) Init(10) Param Optimization
Bound on the complexity of the expressions in the scalar evolutions analyzer.

-param=scev-max-expr-size=
Common Joined UInteger Var(param_scev_max_expr_size) Init(100) Param Optimization
Bound on size of expressions used in the scalar evolutions analyzer.

-param=sched-autopref-queue-depth=
Common Joined UInteger Var(param_sched_autopref_queue_depth) Init(-1) Param Optimization
Hardware autoprefetcher scheduler model control flag.  Number of lookahead cycles the model looks into, at '0' only enable instruction sorting heuristic.  Disabled by default.

-param=sched-mem-true-dep-cost=
Common Joined UInteger Var(param_sched_mem_true_dep_cost) Init(1) Param Optimization
Minimal distance between possibly conflicting store and load.

-param=sched-pressure-algorithm=
Common Joined UInteger Var(param_sched_pressure_algorithm) Init(1) IntegerRange(1, 2) Param Optimization
Which -fsched-pressure algorithm to apply.

-param=sched-spec-prob-cutoff=
Common Joined UInteger Var(param_sched_spec_prob_cutoff) Init(40) IntegerRange(0, 100) Param Optimization
The minimal probability of speculation success (in percents), so that speculative insn will be scheduled.

-param=sched-state-edge-prob-cutoff=
Common Joined UInteger Var(param_sched_state_edge_prob_cutoff) Init(10) IntegerRange(0, 100) Param Optimization
The minimum probability an edge must have for the scheduler to save its state across it.

-param=selsched-insns-to-rename=
Common Joined UInteger Var(param_selsched_insns_to_rename) Init(2) Param Optimization
Maximum number of instructions in the ready list that are considered eligible for renaming.

-param=selsched-max-lookahead=
Common Joined UInteger Var(param_selsched_max_lookahead) Init(50) Param Optimization
The maximum size of the lookahead window of selective scheduling.

-param=selsched-max-sched-times=
Common Joined UInteger Var(param_selsched_max_sched_times) Init(2) IntegerRange(1, 65536) Param Optimization
Maximum number of times that an insn could be scheduled.

-param=simultaneous-prefetches=
Common Joined UInteger Var(param_simultaneous_prefetches) Init(3) Param Optimization
The number of prefetches that can run at the same time.

-param=sink-frequency-threshold=
Common Joined UInteger Var(param_sink_frequency_threshold) Init(75) IntegerRange(0, 100) Param Optimization
Target block's relative execution frequency (as a percentage) required to sink a statement.

-param=slp-max-insns-in-bb=
Common Joined UInteger Var(param_slp_max_insns_in_bb) Init(1000) Param Optimization
Maximum number of instructions in basic block to be considered for SLP vectorization.

-param=sms-dfa-history=
Common Joined UInteger Var(param_sms_dfa_history) IntegerRange(0, 16) Param Optimization
The number of cycles the swing modulo scheduler considers when checking conflicts using DFA.

-param=sms-loop-average-count-threshold=
Common Joined UInteger Var(param_sms_loop_average_count_threshold) Param Optimization
A threshold on the average loop count considered by the swing modulo scheduler.

-param=sms-max-ii-factor=
Common Joined UInteger Var(param_sms_max_ii_factor) Init(2) IntegerRange(1, 16) Param Optimization
A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop.

-param=sms-min-sc=
Common Joined UInteger Var(param_sms_min_sc) Init(2) IntegerRange(1, 2) Param Optimization
The minimum value of stage count that swing modulo scheduler will generate.

-param=sra-max-scalarization-size-Osize=
Common Joined UInteger Var(param_sra_max_scalarization_size_size) Param Optimization
Maximum size, in storage units, of an aggregate which should be considered for scalarization when compiling for size.

-param=sra-max-scalarization-size-Ospeed=
Common Joined UInteger Var(param_sra_max_scalarization_size_speed) Param Optimization
Maximum size, in storage units, of an aggregate which should be considered for scalarization when compiling for speed.

-param=sra-max-propagations=
Common Joined UInteger Var(param_sra_max_propagations) Param Optimization Init(32)
Maximum number of artificial accesses to enable forward propagation that Scalar Replacement of Aggregates will keep for one local variable.

-param=ssa-name-def-chain-limit=
Common Joined UInteger Var(param_ssa_name_def_chain_limit) Init(512) Param Optimization
The maximum number of SSA_NAME assignments to follow in determining a value.

-param=ssp-buffer-size=
Common Joined UInteger Var(param_ssp_buffer_size) Init(8) IntegerRange(1, 65536) Param Optimization
The lower bound for a buffer to be considered for stack smashing protection.

-param=stack-clash-protection-guard-size=
Common Joined UInteger Var(param_stack_clash_protection_guard_size) Init(12) IntegerRange(12, 30) Param Optimization
Size of the stack guard expressed as a power of two in bytes.

-param=stack-clash-protection-probe-interval=
Common Joined UInteger Var(param_stack_clash_protection_probe_interval) Init(12) IntegerRange(10, 16) Param Optimization
Interval in which to probe the stack expressed as a power of two in bytes.

-param=store-merging-allow-unaligned=
Common Joined UInteger Var(param_store_merging_allow_unaligned) Init(1) IntegerRange(0, 1) Param Optimization
Allow the store merging pass to introduce unaligned stores if it is legal to do so.

-param=store-merging-max-size=
Common Joined UInteger Var(param_store_merging_max_size) Init(65536) IntegerRange(1, 65536) Param Optimization
Maximum size of a single store merging region in bytes.

-param=switch-conversion-max-branch-ratio=
Common Joined UInteger Var(param_switch_conversion_branch_ratio) Init(8) IntegerRange(1, 65536) Param Optimization
The maximum ratio between array size and switch branches for a switch conversion to take place.

-param=tm-max-aggregate-size=
Common Joined UInteger Var(param_tm_max_aggregate_size) Init(9) Param Optimization
Size in bytes after which thread-local aggregates should be instrumented with the logging functions instead of save/restore pairs.

-param=tracer-dynamic-coverage=
Common Joined UInteger Var(param_tracer_dynamic_coverage) Init(75) IntegerRange(0, 100) Param Optimization
The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is not available.

-param=tracer-dynamic-coverage-feedback=
Common Joined UInteger Var(param_tracer_dynamic_coverage_feedback) Init(95) IntegerRange(0, 100) Param Optimization
The percentage of function, weighted by execution frequency, that must be covered by trace formation. Used when profile feedback is available.

-param=tracer-max-code-growth=
Common Joined UInteger Var(param_tracer_max_code_growth) Init(100) Param Optimization
Maximal code growth caused by tail duplication (in percent).

-param=tracer-min-branch-probability=
Common Joined UInteger Var(param_tracer_min_branch_probability) Init(50) IntegerRange(0, 100) Param Optimization
Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is not available.

-param=tracer-min-branch-probability-feedback=
Common Joined UInteger Var(param_tracer_min_branch_probability_feedback) Init(80) IntegerRange(0, 100) Param Optimization
Stop forward growth if the probability of best edge is less than this threshold (in percent). Used when profile feedback is available.

-param=tracer-min-branch-ratio=
Common Joined UInteger Var(param_tracer_min_branch_ratio) Init(10) IntegerRange(0, 100) Param Optimization
Stop reverse growth if the reverse probability of best edge is less than this threshold (in percent).

-param=tree-reassoc-width=
Common Joined UInteger Var(param_tree_reassoc_width) Param Optimization
Set the maximum number of instructions executed in parallel in reassociated tree.  If 0, use the target dependent heuristic.

-param=uninit-control-dep-attempts=
Common Joined UInteger Var(param_uninit_control_dep_attempts) Init(1000) IntegerRange(1, 65536) Param Optimization
Maximum number of nested calls to search for control dependencies during uninitialized variable analysis.

-param=uninlined-function-insns=
Common Joined UInteger Var(param_uninlined_function_insns) Init(2) Optimization IntegerRange(0, 1000000) Param
Instruction accounted for function prologue, epilogue and other overhead.

-param=uninlined-function-time=
Common Joined UInteger Var(param_uninlined_function_time) Optimization IntegerRange(0, 1000000) Param
Time accounted for function prologue, epilogue and other overhead.

-param=uninlined-thunk-insns=
Common Joined UInteger Var(param_uninlined_function_thunk_insns) Optimization Init(2) IntegerRange(0, 1000000) Param
Instruction accounted for function thunk overhead.

-param=uninlined-thunk-time=
Common Joined UInteger Var(param_uninlined_function_thunk_time) Optimization Init(2) IntegerRange(0, 1000000) Param
Time accounted for function thunk overhead.

-param=unlikely-bb-count-fraction=
Common Joined UInteger Var(param_unlikely_bb_count_fraction) Init(20) Param Optimization
The denominator n of fraction 1/n of the number of profiled runs of the entire program below which the execution count of a basic block must be in order for the basic block to be considered unlikely.

-param=unroll-jam-max-unroll=
Common Joined UInteger Var(param_unroll_jam_max_unroll) Init(4) Param Optimization
Maximum unroll factor for the unroll-and-jam transformation.

-param=unroll-jam-min-percent=
Common Joined UInteger Var(param_unroll_jam_min_percent) Init(1) IntegerRange(0, 100) Param Optimization
Minimum percentage of memrefs that must go away for unroll-and-jam to be considered profitable.

-param=use-after-scope-direct-emission-threshold=
Common Joined UInteger Var(param_use_after_scope_direct_emission_threshold) Init(256) Param Optimization
Use direct poisoning/unpoisoning instructions for variables smaller or equal to this number.

-param=use-canonical-types=
Common Joined UInteger Var(param_use_canonical_types) Init(1) IntegerRange(0, 1) Param
Whether to use canonical types.

-param=vect-epilogues-nomask=
Common Joined UInteger Var(param_vect_epilogues_nomask) Init(1) IntegerRange(0, 1) Param Optimization
Enable loop epilogue vectorization using smaller vector size.

-param=vect-max-peeling-for-alignment=
Common Joined UInteger Var(param_vect_max_peeling_for_alignment) Init(-1) IntegerRange(-1, 64) Param Optimization
Maximum number of loop peels to enhance alignment of data references in a loop.

-param=vect-max-version-for-alias-checks=
Common Joined UInteger Var(param_vect_max_version_for_alias_checks) Init(10) Param Optimization
Bound on number of runtime checks inserted by the vectorizer's loop versioning for alias check.

-param=vect-max-version-for-alignment-checks=
Common Joined UInteger Var(param_vect_max_version_for_alignment_checks) Init(6) Param Optimization
Bound on number of runtime checks inserted by the vectorizer's loop versioning for alignment check.

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