Package daikon.inv.unary.scalar

Class RangeInt.PowerOfTwo

Object

Invariant

UnaryInvariant

SingleScalar

RangeInt

PowerOfTwo

All Implemented Interfaces:

Serializable, Cloneable

Enclosing class:

RangeInt

public static class RangeInt.PowerOfTwo
extends RangeInt

Invariant representing longs whose values are always a power of 2 (exactly one bit is set). Used for non-instantiating suppressions. Since this is not covered by the Bound or OneOf invariants it is printed. Prints as x is a power of 2.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class RangeInt

RangeInt.BooleanVal, RangeInt.Bound0_63, RangeInt.EqualMinusOne, RangeInt.EqualOne, RangeInt.EqualZero, RangeInt.Even, RangeInt.GreaterEqual64, RangeInt.GreaterEqualZero, RangeInt.PowerOfTwo

Nested classes/interfaces inherited from class Invariant

Invariant.ClassVarnameComparator, Invariant.ClassVarnameFormulaComparator, Invariant.InvariantComparatorForPrinting, Invariant.Match

Field Summary

Fields

Modifier and Type	Field	Description
static boolean	dkconfig_enabled	Boolean.

Fields inherited from class Invariant

CONFIDENCE_JUSTIFIED, CONFIDENCE_NEVER, CONFIDENCE_UNJUSTIFIED, debug, debugFlow, debugGuarding, debugIsObvious, debugIsWorthPrinting, debugPrint, debugPrintEquality, dkconfig_confidence_limit, dkconfig_fuzzy_ratio, dkconfig_simplify_define_predicates, falsified, invariantEnabledDefault, isGuardingPredicate, min_mod_non_missing_samples, ppt, PROBABILITY_JUSTIFIED, PROBABILITY_NEVER, PROBABILITY_UNJUSTIFIED

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PowerOfTwo()
protected	PowerOfTwo(PptSlice ppt)

Method Summary

Modifier and Type	Method	Description
boolean	enabled()	returns whether or not this invariant is enabled
boolean	eq_check(long x)	Returns true if x is a power of 2 (has one bit on).
String	get_format_str(OutputFormat format)	Return a format string for the specified output format.
static RangeInt.PowerOfTwo	get_proto()	returns the prototype invariant
RangeInt.PowerOfTwo	instantiate_dyn(PptSlice slice)	instantiates the invariant on the specified slice
@Nullable DiscardInfo	isObviousDynamically(VarInfo[] vis)	Since PowerOfTwo is not covered by Bound or OneOf, it is not obvious (and should thus be printed).

Methods inherited from class RangeInt

add_modified, check_modified, computeConfidence, find_oneof, format_using, get_proto_all, instantiate_ok, isExclusiveFormula, isSameFormula

Methods inherited from class SingleScalar

add, add_unmodified, check, check_unmodified, valid_types, valid_types_static, var

Methods inherited from class UnaryInvariant

resurrect_done

Methods inherited from class Invariant

add_sample, asInvClass, checkRep, clear_falsified, clone, clone_and_permute, conf_is_ge, confidence_and, confidence_and, confidence_or, createGuardedInvariant, createGuardingPredicate, enoughSamples, falsify, find, format, format_classname, format_too_few_samples, format_unimplemented, formatFuzzy, get_comparability, get_ni_suppressions, getConfidence, getGuardingList, getGuardingList, hasUninterestingConstant, instantiate, is_false, is_ni_suppressed, isActive, isAllPrestate, isEqualityComparison, isExact, isObvious, isObviousDynamically, isObviousDynamically_SomeInEquality, isObviousDynamically_SomeInEqualityHelper, isObviousStatically, isObviousStatically, isObviousStatically_AllInEquality, isObviousStatically_SomeInEquality, isObviousStatically_SomeInEqualityHelper, isReflexive, isSameInvariant, isValidEscExpression, isValidExpression, isWorthPrinting, justified, log, log, logDetail, logOn, match, merge, mergeFormulasOk, permute, prob_and, prob_and, prob_is_ge, prob_or, repCheck, repr, repr_prob, resurrect, simplify_format_double, simplify_format_long, simplify_format_string, state_match, toString, toString, transfer, usesVar, usesVar, usesVarDerived, varNames

Methods inherited from class Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

dkconfig_enabled

public static boolean dkconfig_enabled

Boolean. True if PowerOfTwo invariants should be considered.

Constructor Detail

PowerOfTwo

protected PowerOfTwo(PptSlice ppt)

PowerOfTwo

protected PowerOfTwo()

Method Detail

get_proto

public static RangeInt.PowerOfTwo get_proto()

returns the prototype invariant

enabled

public boolean enabled()

returns whether or not this invariant is enabled

Specified by:

enabled in class Invariant

instantiate_dyn

public RangeInt.PowerOfTwo instantiate_dyn( RangeInt.PowerOfTwo this,
                                           PptSlice slice)

instantiates the invariant on the specified slice

Specified by:

instantiate_dyn in class Invariant

Returns:

the new invariant

get_format_str

public String get_format_str(@GuardSatisfied RangeInt.PowerOfTwo this,
                             OutputFormat format)

Description copied from class: RangeInt

Return a format string for the specified output format. Each instance of %varN% will be replaced by the correct name for varN.

Specified by:

get_format_str in class RangeInt

eq_check

public boolean eq_check(long x)

Returns true if x is a power of 2 (has one bit on). The check is to and x with itself - 1. The theory is that if there are multiple bits turned on, at least one of those bits is unmodified by a subtract operation and thus the bitwise-and be non-zero. There is probably a more elegant way to do this.

Specified by:

eq_check in class RangeInt

isObviousDynamically

@Pure
public @Nullable DiscardInfo isObviousDynamically(VarInfo[] vis)

Since PowerOfTwo is not covered by Bound or OneOf, it is not obvious (and should thus be printed).

Overrides:

isObviousDynamically in class RangeInt