/// This is an important base class in LLVM. It provides the common facilities
/// of all constant values in an LLVM program. A constant is a value that is
/// immutable at runtime. Functions are constants because their address is
-/// immutable. Same with global variables.
-///
+/// immutable. Same with global variables.
+///
/// All constants share the capabilities provided in this class. All constants
/// can have a null value. They can have an operand list. Constants can be
/// simple (integer and floating point values), complex (arrays and structures),
-/// or expression based (computations yielding a constant value composed of
+/// or expression based (computations yielding a constant value composed of
/// only certain operators and other constant values).
-///
-/// Note that Constants are immutable (once created they never change)
-/// and are fully shared by structural equivalence. This means that two
-/// structurally equivalent constants will always have the same address.
-/// Constants are created on demand as needed and never deleted: thus clients
+///
+/// Note that Constants are immutable (once created they never change)
+/// and are fully shared by structural equivalence. This means that two
+/// structurally equivalent constants will always have the same address.
+/// Constants are created on demand as needed and never deleted: thus clients
/// don't have to worry about the lifetime of the objects.
/// @brief LLVM Constant Representation
class Constant : public User {
- void operator=(const Constant &) LLVM_DELETED_FUNCTION;
- Constant(const Constant &) LLVM_DELETED_FUNCTION;
+ void operator=(const Constant &) = delete;
+ Constant(const Constant &) = delete;
void anchor() override;
protected:
Constant(Type *ty, ValueTy vty, Use *Ops, unsigned NumOps)
: User(ty, vty, Ops, NumOps) {}
- void destroyConstantImpl();
public:
/// isNullValue - Return true if this is the value that would be returned by
/// getNullValue.
bool isNullValue() const;
+ /// \brief Returns true if the value is one.
+ bool isOneValue() const;
+
/// isAllOnesValue - Return true if this is the value that would be returned by
/// getAllOnesValue.
bool isAllOnesValue() const;
- /// isNegativeZeroValue - Return true if the value is what would be returned
+ /// isNegativeZeroValue - Return true if the value is what would be returned
/// by getZeroValueForNegation.
bool isNegativeZeroValue() const;
/// Return true if the value is negative zero or null value.
bool isZeroValue() const;
+ /// \brief Return true if the value is not the smallest signed value.
+ bool isNotMinSignedValue() const;
+
+ /// \brief Return true if the value is the smallest signed value.
+ bool isMinSignedValue() const;
+
/// canTrap - Return true if evaluation of this constant could trap. This is
/// true for things like constant expressions that could divide by zero.
bool canTrap() const;
/// whether or not it may generate a relocation entry. This must be
/// conservative, so if it might codegen to a relocatable entry, it should say
/// so. The return values are:
- ///
+ ///
/// NoRelocation: This constant pool entry is guaranteed to never have a
/// relocation applied to it (because it holds a simple constant like
/// '4').
/// vector of constant integers, all equal, and the common value is returned.
const APInt &getUniqueInteger() const;
- /// destroyConstant - Called if some element of this constant is no longer
- /// valid. At this point only other constants may be on the use_list for this
+ /// Called if some element of this constant is no longer valid.
+ /// At this point only other constants may be on the use_list for this
/// constant. Any constants on our Use list must also be destroy'd. The
/// implementation must be sure to remove the constant from the list of
- /// available cached constants. Implementations should call
- /// destroyConstantImpl as the last thing they do, to destroy all users and
- /// delete this.
- virtual void destroyConstant() { llvm_unreachable("Not reached!"); }
+ /// available cached constants. Implementations should implement
+ /// destroyConstantImpl to remove constants from any pools/maps they are
+ /// contained it.
+ void destroyConstant();
//// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Value *V) {
V->getValueID() <= ConstantLastVal;
}
- /// replaceUsesOfWithOnConstant - This method is a special form of
- /// User::replaceUsesOfWith (which does not work on constants) that does work
+ /// This method is a special form of User::replaceUsesOfWith
+ /// (which does not work on constants) that does work
/// on constants. Basically this method goes through the trouble of building
/// a new constant that is equivalent to the current one, with all uses of
/// From replaced with uses of To. After this construction is completed, all
/// use Value::replaceAllUsesWith, which automatically dispatches to this
/// method as needed.
///
- virtual void replaceUsesOfWithOnConstant(Value *, Value *, Use *) {
- // Provide a default implementation for constants (like integers) that
- // cannot use any other values. This cannot be called at runtime, but needs
- // to be here to avoid link errors.
- assert(getNumOperands() == 0 && "replaceUsesOfWithOnConstant must be "
- "implemented for all constants that have operands!");
- llvm_unreachable("Constants that do not have operands cannot be using "
- "'From'!");
- }
+ void handleOperandChange(Value *, Value *, Use *);
static Constant *getNullValue(Type* Ty);
/// getIntegerValue - Return the value for an integer or pointer constant,
/// or a vector thereof, with the given scalar value.
- static Constant *getIntegerValue(Type* Ty, const APInt &V);
-
+ static Constant *getIntegerValue(Type *Ty, const APInt &V);
+
/// removeDeadConstantUsers - If there are any dead constant users dangling
/// off of this constant, remove them. This method is useful for clients
/// that want to check to see if a global is unused, but don't want to deal