-//===-- ConstantHandling.h - Stuff for manipulating constants ---*- C++ -*-===//
+//===-- ConstantFolding.h - Internal Constant Folding Interface -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
//
-// This file contains the declarations of some cool operators that allow you
-// to do natural things with constant pool values.
+// This file defines the (internal) constant folding interfaces for LLVM. These
+// interfaces are used by the ConstantExpr::get* methods to automatically fold
+// constants when possible.
//
-// Unfortunately we can't overload operators on pointer types (like this:)
-//
-// inline bool operator==(const Constant *V1, const Constant *V2)
-//
-// so we must make due with references, even though it leads to some butt ugly
-// looking code downstream. *sigh* (ex: Constant *Result = *V1 + *v2; )
-//
-//===----------------------------------------------------------------------===//
-//
-// WARNING: These operators may return a null object if I don't know how to
-// perform the specified operation on the specified constant types.
-//
-//===----------------------------------------------------------------------===//
-//
-// Implementation notes:
-// This library is implemented this way for a reason: In most cases, we do
-// not want to have to link the constant mucking code into an executable.
-// We do, however want to tie some of this into the main type system, as an
-// optional component. By using a mutable cache member in the Type class, we
-// get exactly the kind of behavior we want.
-//
-// In the end, we get performance almost exactly the same as having a virtual
-// function dispatch, but we don't have to put our virtual functions into the
-// "Type" class, and we can implement functionality with templates. Good deal.
+// These operators may return a null object if I don't know how to perform the
+// specified operation on the specified constant types.
//
//===----------------------------------------------------------------------===//
-#ifndef LLVM_CONSTANTHANDLING_H
-#define LLVM_CONSTANTHANDLING_H
+#ifndef CONSTANTFOLDING_H
+#define CONSTANTFOLDING_H
-#include "llvm/Constants.h"
-#include "llvm/Type.h"
+#include <vector>
namespace llvm {
-
-class PointerType;
-
-//===----------------------------------------------------------------------===//
-// Implement all other operators indirectly through TypeRules system
-//===----------------------------------------------------------------------===//
-
-struct ConstRules {
- ConstRules() {}
-
- // Binary Operators...
- virtual Constant *add(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *sub(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *mul(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *div(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *rem(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *op_and(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *op_or (const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *op_xor(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *shl(const Constant *V1, const Constant *V2) const = 0;
- virtual Constant *shr(const Constant *V1, const Constant *V2) const = 0;
-
- virtual ConstantBool *lessthan(const Constant *V1,
- const Constant *V2) const = 0;
- virtual ConstantBool *equalto(const Constant *V1,
- const Constant *V2) const = 0;
-
- // Casting operators. ick
- virtual ConstantBool *castToBool (const Constant *V) const = 0;
- virtual ConstantSInt *castToSByte (const Constant *V) const = 0;
- virtual ConstantUInt *castToUByte (const Constant *V) const = 0;
- virtual ConstantSInt *castToShort (const Constant *V) const = 0;
- virtual ConstantUInt *castToUShort(const Constant *V) const = 0;
- virtual ConstantSInt *castToInt (const Constant *V) const = 0;
- virtual ConstantUInt *castToUInt (const Constant *V) const = 0;
- virtual ConstantSInt *castToLong (const Constant *V) const = 0;
- virtual ConstantUInt *castToULong (const Constant *V) const = 0;
- virtual ConstantFP *castToFloat (const Constant *V) const = 0;
- virtual ConstantFP *castToDouble(const Constant *V) const = 0;
- virtual Constant *castToPointer(const Constant *V,
- const PointerType *Ty) const = 0;
-
- inline Constant *castTo(const Constant *V, const Type *Ty) const {
- switch (Ty->getPrimitiveID()) {
- case Type::BoolTyID: return castToBool(V);
- case Type::UByteTyID: return castToUByte(V);
- case Type::SByteTyID: return castToSByte(V);
- case Type::UShortTyID: return castToUShort(V);
- case Type::ShortTyID: return castToShort(V);
- case Type::UIntTyID: return castToUInt(V);
- case Type::IntTyID: return castToInt(V);
- case Type::ULongTyID: return castToULong(V);
- case Type::LongTyID: return castToLong(V);
- case Type::FloatTyID: return castToFloat(V);
- case Type::DoubleTyID: return castToDouble(V);
- case Type::PointerTyID:
- return castToPointer(V, reinterpret_cast<const PointerType*>(Ty));
- default: return 0;
- }
- }
-
- // ConstRules::get - Return an instance of ConstRules for the specified
- // constant operands.
- //
- static ConstRules &get(const Constant &V1, const Constant &V2);
-private:
- ConstRules(const ConstRules &); // Do not implement
- ConstRules &operator=(const ConstRules &); // Do not implement
-};
-
-// Unary operators...
-inline Constant *operator~(const Constant &V) {
- assert(V.getType()->isIntegral() && "Cannot invert non-integral constant!");
- return ConstRules::get(V, V).op_xor(&V,
- ConstantInt::getAllOnesValue(V.getType()));
-}
-
-inline Constant *operator-(const Constant &V) {
- return ConstRules::get(V, V).sub(Constant::getNullValue(V.getType()), &V);
-}
-
-// Standard binary operators...
-inline Constant *operator+(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).add(&V1, &V2);
-}
-
-inline Constant *operator-(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).sub(&V1, &V2);
-}
-
-inline Constant *operator*(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).mul(&V1, &V2);
-}
-
-inline Constant *operator/(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).div(&V1, &V2);
-}
-
-inline Constant *operator%(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).rem(&V1, &V2);
-}
-
-// Logical Operators...
-inline Constant *operator&(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).op_and(&V1, &V2);
-}
-
-inline Constant *operator|(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).op_or(&V1, &V2);
-}
-
-inline Constant *operator^(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).op_xor(&V1, &V2);
-}
-
-// Shift Instructions...
-inline Constant *operator<<(const Constant &V1, const Constant &V2) {
- assert(V1.getType()->isInteger() && V2.getType() == Type::UByteTy);
- return ConstRules::get(V1, V2).shl(&V1, &V2);
-}
-
-inline Constant *operator>>(const Constant &V1, const Constant &V2) {
- assert(V1.getType()->isInteger() && V2.getType() == Type::UByteTy);
- return ConstRules::get(V1, V2).shr(&V1, &V2);
-}
-
-inline ConstantBool *operator<(const Constant &V1,
- const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).lessthan(&V1, &V2);
-}
-
-inline ConstantBool *operator==(const Constant &V1, const Constant &V2) {
- assert(V1.getType() == V2.getType() && "Constant types must be identical!");
- return ConstRules::get(V1, V2).equalto(&V1, &V2);
-}
-
-//===----------------------------------------------------------------------===//
-// Implement 'derived' operators based on what we already have...
-//===----------------------------------------------------------------------===//
-
-inline ConstantBool *operator!=(const Constant &V1, const Constant &V2) {
- if (ConstantBool *V = (V1 == V2))
- return V->inverted(); // !(V1 == V2)
- return 0;
-}
-
-inline ConstantBool *operator>(const Constant &V1,
- const Constant &V2) {
- return V2 < V1;
-}
-
-inline ConstantBool *operator>=(const Constant &V1,
- const Constant &V2) {
- if (ConstantBool *V = (V1 < V2))
- return V->inverted(); // !(V1 < V2)
- return 0;
-}
-
-inline ConstantBool *operator<=(const Constant &V1,
- const Constant &V2) {
- if (ConstantBool *V = (V1 > V2))
- return V->inverted(); // !(V1 > V2)
- return 0;
-}
-
-
-//===----------------------------------------------------------------------===//
-// Implement higher level instruction folding type instructions
-//===----------------------------------------------------------------------===//
-
-// Constant fold various types of instruction...
-Constant *ConstantFoldCastInstruction(const Constant *V, const Type *DestTy);
-Constant *ConstantFoldBinaryInstruction(unsigned Opcode, const Constant *V1,
- const Constant *V2);
-Constant *ConstantFoldShiftInstruction(unsigned Opcode, const Constant *V1,
- const Constant *V2);
-Constant *ConstantFoldGetElementPtr(const Constant *C,
- const std::vector<Constant*> &IdxList);
-
+ class Constant;
+ struct Type;
+
+ // Constant fold various types of instruction...
+ Constant *ConstantFoldCastInstruction(const Constant *V, const Type *DestTy);
+ Constant *ConstantFoldSelectInstruction(const Constant *Cond,
+ const Constant *V1,
+ const Constant *V2);
+ Constant *ConstantFoldBinaryInstruction(unsigned Opcode, const Constant *V1,
+ const Constant *V2);
+ Constant *ConstantFoldGetElementPtr(const Constant *C,
+ const std::vector<Constant*> &IdxList);
} // End llvm namespace
#endif