ValueRangePropagator

ValueRangePropagator to figure out if it is safe to truncate a value to make it fit in a smaller type.

It does so by computing the range of possible values the expression can take and checking if that range fit in a given type.

It is only specialized for uint and ulong, as smaller integral type are promoted before any computation to 32bits values and above. As a result, smaller types do not really matter as long as we promote them properly. As a result, ranges computed from improperly promoted expression may be extremely pessimistics.

struct ValueRangePropagator (

) if (

is(T == uint) ||

is(T == ulong)

) {

alias VR = ValueRange!T;

this(SemanticPass pass);

bool canFit(Expression e, Type t);

bool canFit(Expression e, BuiltinType t);

VR visit(Expression e);

VR visit(BooleanLiteral e);

VR visit(IntegerLiteral e);

VR visit(BinaryExpression e);

VR visit(UnaryExpression e);

VR visit(VariableExpression e);

VR visit(Variable v);

VR visit(CastExpression e);

}

Constructors

this this(SemanticPass pass): Undocumented in source.

VR alias VR = ValueRange!T: Undocumented in source.

Functions

canFit bool canFit(Expression e, Type t): Undocumented in source.
canFit bool canFit(Expression e, BuiltinType t): Undocumented in source.
visit VR visit(Expression e): Undocumented in source.
visit VR visit(BooleanLiteral e): Undocumented in source. Be warned that the author may not have intended to support it.
visit VR visit(IntegerLiteral e): Undocumented in source. Be warned that the author may not have intended to support it.
visit VR visit(BinaryExpression e): Undocumented in source. Be warned that the author may not have intended to support it.
visit VR visit(UnaryExpression e): Undocumented in source. Be warned that the author may not have intended to support it.
visit VR visit(VariableExpression e): Undocumented in source. Be warned that the author may not have intended to support it.
visit VR visit(Variable v): Undocumented in source.
visit VR visit(CastExpression e): Undocumented in source. Be warned that the author may not have intended to support it.

ValueRangePropagator

Constructors

Alias This

Members

Aliases

Functions

Meta

Source