llvm-6502/include/llvm/Operator.h
Dan Gohman 344df5ecdf Clarify that OverflowingBinaryOperator is not used for SDiv, even though
SDiv is a binary operation that can overflow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76464 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-20 20:32:43 +00:00

193 lines
6.5 KiB
C++

//===-- llvm/Operator.h - Operator utility subclass -------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines various classes for working with Instructions and
// ConstantExprs.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_OPERATOR_H
#define LLVM_OPERATOR_H
#include "llvm/Instruction.h"
#include "llvm/Constants.h"
namespace llvm {
/// Operator - This is a utility class that provides an abstraction for the
/// common functionality between Instructions and ConstantExprs.
///
class Operator : public User {
private:
// Do not implement any of these. The Operator class is intended to be used
// as a utility, and is never itself instantiated.
void *operator new(size_t, unsigned);
void *operator new(size_t s);
Operator();
~Operator();
public:
/// getOpcode - Return the opcode for this Instruction or ConstantExpr.
///
unsigned getOpcode() const {
if (const Instruction *I = dyn_cast<Instruction>(this))
return I->getOpcode();
return cast<ConstantExpr>(this)->getOpcode();
}
/// getOpcode - If V is an Instruction or ConstantExpr, return its
/// opcode. Otherwise return UserOp1.
///
static unsigned getOpcode(const Value *V) {
if (const Instruction *I = dyn_cast<Instruction>(V))
return I->getOpcode();
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
return CE->getOpcode();
return Instruction::UserOp1;
}
static inline bool classof(const Operator *) { return true; }
static inline bool classof(const Instruction *I) { return true; }
static inline bool classof(const ConstantExpr *I) { return true; }
static inline bool classof(const Value *V) {
return isa<Instruction>(V) || isa<ConstantExpr>(V);
}
};
/// OverflowingBinaryOperator - Utility class for integer arithmetic operators
/// which may exhibit overflow - Add, Sub, and Mul. It does not include SDiv,
/// despite that operator having the potential for overflow.
///
class OverflowingBinaryOperator : public Operator {
public:
/// hasNoSignedOverflow - Test whether this operation is known to never
/// undergo signed overflow.
bool hasNoSignedOverflow() const {
return SubclassOptionalData & (1 << 0);
}
void setHasNoSignedOverflow(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0);
}
/// hasNoUnsignedOverflow - Test whether this operation is known to never
/// undergo unsigned overflow.
bool hasNoUnsignedOverflow() const {
return SubclassOptionalData & (1 << 1);
}
void setHasNoUnsignedOverflow(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 1)) | (B << 1);
}
static inline bool classof(const OverflowingBinaryOperator *) { return true; }
static inline bool classof(const Instruction *I) {
return I->getOpcode() == Instruction::Add ||
I->getOpcode() == Instruction::Sub ||
I->getOpcode() == Instruction::Mul;
}
static inline bool classof(const ConstantExpr *CE) {
return CE->getOpcode() == Instruction::Add ||
CE->getOpcode() == Instruction::Sub ||
CE->getOpcode() == Instruction::Mul;
}
static inline bool classof(const Value *V) {
return (isa<Instruction>(V) && classof(cast<Instruction>(V))) ||
(isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
}
};
/// SDivOperator - An Operator with opcode Instruction::SDiv.
///
class SDivOperator : public Operator {
public:
/// isExact - Test whether this division is known to be exact, with
/// zero remainder.
bool isExact() const {
return SubclassOptionalData & (1 << 0);
}
void setIsExact(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0);
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const SDivOperator *) { return true; }
static inline bool classof(const ConstantExpr *CE) {
return CE->getOpcode() == Instruction::SDiv;
}
static inline bool classof(const Instruction *I) {
return I->getOpcode() == Instruction::SDiv;
}
static inline bool classof(const Value *V) {
return (isa<Instruction>(V) && classof(cast<Instruction>(V))) ||
(isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
}
};
class GEPOperator : public Operator {
public:
inline op_iterator idx_begin() { return op_begin()+1; }
inline const_op_iterator idx_begin() const { return op_begin()+1; }
inline op_iterator idx_end() { return op_end(); }
inline const_op_iterator idx_end() const { return op_end(); }
Value *getPointerOperand() {
return getOperand(0);
}
const Value *getPointerOperand() const {
return getOperand(0);
}
static unsigned getPointerOperandIndex() {
return 0U; // get index for modifying correct operand
}
/// getPointerOperandType - Method to return the pointer operand as a
/// PointerType.
const PointerType *getPointerOperandType() const {
return reinterpret_cast<const PointerType*>(getPointerOperand()->getType());
}
unsigned getNumIndices() const { // Note: always non-negative
return getNumOperands() - 1;
}
bool hasIndices() const {
return getNumOperands() > 1;
}
/// hasAllZeroIndices - Return true if all of the indices of this GEP are
/// zeros. If so, the result pointer and the first operand have the same
/// value, just potentially different types.
bool hasAllZeroIndices() const {
for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) {
if (Constant *C = dyn_cast<Constant>(I))
if (C->isNullValue())
continue;
return false;
}
return true;
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const GEPOperator *) { return true; }
static inline bool classof(const GetElementPtrInst *) { return true; }
static inline bool classof(const ConstantExpr *CE) {
return CE->getOpcode() == Instruction::GetElementPtr;
}
static inline bool classof(const Instruction *I) {
return I->getOpcode() == Instruction::GetElementPtr;
}
static inline bool classof(const Value *V) {
return isa<GetElementPtrInst>(V) ||
(isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
}
};
} // End llvm namespace
#endif