```
C:\QtSDK1.2.1\mingw\bin>g++ --help=params
The --param option recognizes the following as parameters:
sra-max-structure-size The maximum structure size (in bytes) for which
GCC will use by-element copies
sra-max-structure-count The maximum number of structure fields for which
GCC will use by-element copies
sra-field-structure-ratio The threshold ratio between instantiated fields
and the total structure size
struct-reorg-cold-struct-ratio The threshold ratio between current and
hottest structure counts
predictable-branch-outcome Maximal esitmated outcome of branch considered
predictable
max-inline-insns-single The maximum number of instructions in a single
function eligible for inlining
max-inline-insns-auto The maximum number of instructions when
automatically inlining
max-inline-insns-recursive The maximum number of instructions inline
function can grow to via recursive inlining
max-inline-insns-recursive-auto The maximum number of instructions non-inline
function can grow to via recursive inlining
max-inline-recursive-depth The maximum depth of recursive inlining for
inline functions
max-inline-recursive-depth-auto The maximum depth of recursive inlining for
non-inline functions
min-inline-recursive-probability Inline recursively only when the probability
of call being executed exceeds the parameter
max-variable-expansions-in-unroller If -fvariable-expansion-in-unroller is
used, the maximum number of times that an
individual variable will be expanded during loop
unrolling
min-vect-loop-bound If -ftree-vectorize is used, the minimal loop
bound of a loop to be considered for vectorization
max-delay-slot-insn-search The maximum number of instructions to consider to
fill a delay slot
max-delay-slot-live-search The maximum number of instructions to consider to
find accurate live register information
max-pending-list-length The maximum length of scheduling's pending
operations list
large-function-insns The size of function body to be considered large
large-function-growth Maximal growth due to inlining of large function
(in percent)
large-unit-insns The size of translation unit to be considered
large
inline-unit-growth how much can given compilation unit grow because
of the inlining (in percent)
ipcp-unit-growth how much can given compilation unit grow because
of the interprocedural constant propagation (in
percent)
inline-call-cost expense of call operation relative to ordinary
arithmetic operations
large-stack-frame The size of stack frame to be considered large
large-stack-frame-growth Maximal stack frame growth due to inlining (in
percent)
max-gcse-memory The maximum amount of memory to be allocated by
GCSE
max-gcse-passes The maximum number of passes to make when doing
GCSE
gcse-after-reload-partial-fraction The threshold ratio for performing partial
redundancy elimination after reload
gcse-after-reload-critical-fraction The threshold ratio of critical edges
execution count that permit performing redundancy
elimination after reload
max-unrolled-insns The maximum number of instructions to consider to
unroll in a loop
max-average-unrolled-insns The maximum number of instructions to consider to
unroll in a loop on average
max-unroll-times The maximum number of unrollings of a single loop
max-peeled-insns The maximum number of insns of a peeled loop
max-peel-times The maximum number of peelings of a single loop
max-completely-peeled-insns The maximum number of insns of a completely
peeled loop
max-completely-peel-times The maximum number of peelings of a single loop
that is peeled completely
max-once-peeled-insns The maximum number of insns of a peeled loop that
rolls only once
max-unswitch-insns The maximum number of insns of an unswitched loop
max-unswitch-level The maximum number of unswitchings in a single
loop
max-iterations-to-track Bound on the number of iterations the brute force
# of iterations analysis algorithm evaluates
max-iterations-computation-cost Bound on the cost of an expression to compute
the number of iterations
sms-max-ii-factor A factor for tuning the upper bound that swing
modulo scheduler uses for scheduling a loop
sms-dfa-history The number of cycles the swing modulo scheduler
considers when checking conflicts using DFA
sms-loop-average-count-threshold A threshold on the average loop count
considered by the swing modulo scheduler
hot-bb-count-fraction Select fraction of the maximal count of
repetitions of basic block in program given basic
block needs to have to be considered hot
hot-bb-frequency-fraction Select fraction of the maximal frequency of
executions of basic block in function given basic
block needs to have to be considered hot
align-threshold Select fraction of the maximal frequency of
executions of basic block in function given basic
block get alignment
align-loop-iterations Loops iterating at least selected number of
iterations will get loop alignement.
max-predicted-iterations The maximum number of loop iterations we predict
statically
tracer-dynamic-coverage-feedback The percentage of function, weighted by
execution frequency, that must be covered by
trace formation. Used when profile feedback is
available
tracer-dynamic-coverage The percentage of function, weighted by execution
frequency, that must be covered by trace
formation. Used when profile feedback is not
available
tracer-max-code-growth Maximal code growth caused by tail duplication
(in percent)
tracer-min-branch-ratio Stop reverse growth if the reverse probability of
best edge is less than this threshold (in percent)
tracer-min-branch-probability-feedback Stop forward growth if the probability
of best edge is less than this threshold (in
percent). Used when profile feedback is available
tracer-min-branch-probability Stop forward growth if the probability of best
edge is less than this threshold (in percent).
Used when profile feedback is not available
max-crossjump-edges The maximum number of incoming edges to consider
for crossjumping
min-crossjump-insns The minimum number of matching instructions to
consider for crossjumping
max-grow-copy-bb-insns The maximum expansion factor when copying basic
blocks
max-goto-duplication-insns The maximum number of insns to duplicate when
unfactoring computed gotos
max-cse-path-length The maximum length of path considered in cse
max-cse-insns The maximum instructions CSE process before
flushing
lim-expensive The minimum cost of an expensive expression in
the loop invariant motion
iv-consider-all-candidates-bound Bound on number of candidates below that all
candidates are considered in iv optimizations
iv-max-considered-uses Bound on number of iv uses in loop optimized in
iv optimizations
iv-always-prune-cand-set-bound If number of candidates in the set is smaller,
we always try to remove unused ivs during its
optimization
scev-max-expr-size Bound on size of expressions used in the scalar
evolutions analyzer
omega-max-vars Bound on the number of variables in Omega
constraint systems
omega-max-geqs Bound on the number of inequalities in Omega
constraint systems
omega-max-eqs Bound on the number of equalities in Omega
constraint systems
omega-max-wild-cards Bound on the number of wild cards in Omega
constraint systems
omega-hash-table-size Bound on the size of the hash table in Omega
constraint systems
omega-max-keys Bound on the number of keys in Omega constraint
systems
omega-eliminate-redundant-constraints When set to 1, use expensive methods to
eliminate all redundant constraints
vect-max-version-for-alignment-checks Bound on number of runtime checks
inserted by the vectorizer's loop versioning for
alignment check
vect-max-version-for-alias-checks Bound on number of runtime checks inserted
by the vectorizer's loop versioning for alias
check
max-cselib-memory-locations The maximum memory locations recorded by cselib
ggc-min-expand Minimum heap expansion to trigger garbage
collection, as a percentage of the total size of
the heap
ggc-min-heapsize Minimum heap size before we start collecting
garbage, in kilobytes
max-reload-search-insns The maximum number of instructions to search
backward when looking for equivalent reload
max-aliased-vops The maximum number of virtual operators that a
function is allowed to have before triggering
memory partitioning heuristics
avg-aliased-vops The average number of virtual operators that
memory statements are allowed to have before
triggering memory partitioning heuristics
max-sched-region-blocks The maximum number of blocks in a region to be
considered for interblock scheduling
max-sched-region-insns The maximum number of insns in a region to be
considered for interblock scheduling
max-pipeline-region-blocks The maximum number of blocks in a region to be
considered for interblock scheduling
max-pipeline-region-insns The maximum number of insns in a region to be
considered for interblock scheduling
min-spec-prob The minimum probability of reaching a source
block for interblock speculative scheduling
max-sched-extend-regions-iters The maximum number of iterations through CFG
to extend regions
max-sched-insn-conflict-delay The maximum conflict delay for an insn to be
considered for speculative motion
sched-spec-prob-cutoff The minimal probability of speculation success
(in percents), so that speculative insn will be
scheduled.
selsched-max-lookahead The maximum size of the lookahead window of
selective scheduling
selsched-max-sched-times Maximum number of times that an insn could be
scheduled
selsched-insns-to-rename Maximum number of instructions in the ready list
that are considered eligible for renaming
sched-mem-true-dep-cost Minimal distance between possibly conflicting
store and load
max-last-value-rtl The maximum number of RTL nodes that can be
recorded as combiner's last value
integer-share-limit The upper bound for sharing integer constants
min-virtual-mappings Minimum number of virtual mappings to consider
switching to full virtual renames
virtual-mappings-ratio Ratio between virtual mappings and virtual
symbols to do full virtual renames
ssp-buffer-size The lower bound for a buffer to be considered for
stack smashing protection
max-jump-thread-duplication-stmts Maximum number of statements allowed in a
block that needs to be duplicated when threading
jumps
max-fields-for-field-sensitive Maximum number of fields in a structure before
pointer analysis treats the structure as a single
variable
max-sched-ready-insns The maximum number of instructions ready to be
issued to be considered by the scheduler during
the first scheduling pass
prefetch-latency The number of insns executed before prefetch is
completed
simultaneous-prefetches The number of prefetches that can run at the same
time
l1-cache-size The size of L1 cache
l1-cache-line-size The size of L1 cache line
l2-cache-size The size of L2 cache
use-canonical-types Whether to use canonical types
max-partial-antic-length Maximum length of partial antic set when
performing tree pre optimization
sccvn-max-scc-size Maximum size of a SCC before SCCVN stops
processing a function
ira-max-loops-num max loops number for regional RA
ira-max-conflict-table-size max size of conflict table in MB
switch-conversion-max-branch-ratio The maximum ratio between array size and
switch branches for a switch conversion to take
place
loop-invariant-max-bbs-in-loop max basic blocks number in loop for loop
invariant motion
```