|
|
//===-- 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_IR_OPERATOR_H
#define LLVM_IR_OPERATOR_H
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
namespace llvm {
class GetElementPtrInst; class BinaryOperator; class ConstantExpr;
/// Operator - This is a utility class that provides an abstraction for the
/// common functionality between Instructions and ConstantExprs.
///
class Operator : public User { private: // The Operator class is intended to be used as a utility, and is never itself
// instantiated.
void *operator new(size_t, unsigned) LLVM_DELETED_FUNCTION; void *operator new(size_t s) LLVM_DELETED_FUNCTION; Operator() LLVM_DELETED_FUNCTION;
protected: // NOTE: Cannot use LLVM_DELETED_FUNCTION because it's not legal to delete
// an overridden method that's not deleted in the base class. Cannot leave
// this unimplemented because that leads to an ODR-violation.
~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 Instruction *) { return true; } static inline bool classof(const ConstantExpr *) { 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: enum { NoUnsignedWrap = (1 << 0), NoSignedWrap = (1 << 1) };
private: friend class BinaryOperator; friend class ConstantExpr; void setHasNoUnsignedWrap(bool B) { SubclassOptionalData = (SubclassOptionalData & ~NoUnsignedWrap) | (B * NoUnsignedWrap); } void setHasNoSignedWrap(bool B) { SubclassOptionalData = (SubclassOptionalData & ~NoSignedWrap) | (B * NoSignedWrap); }
public: /// hasNoUnsignedWrap - Test whether this operation is known to never
/// undergo unsigned overflow, aka the nuw property.
bool hasNoUnsignedWrap() const { return SubclassOptionalData & NoUnsignedWrap; }
/// hasNoSignedWrap - Test whether this operation is known to never
/// undergo signed overflow, aka the nsw property.
bool hasNoSignedWrap() const { return (SubclassOptionalData & NoSignedWrap) != 0; }
static inline bool classof(const Instruction *I) { return I->getOpcode() == Instruction::Add || I->getOpcode() == Instruction::Sub || I->getOpcode() == Instruction::Mul || I->getOpcode() == Instruction::Shl; } static inline bool classof(const ConstantExpr *CE) { return CE->getOpcode() == Instruction::Add || CE->getOpcode() == Instruction::Sub || CE->getOpcode() == Instruction::Mul || CE->getOpcode() == Instruction::Shl; } static inline bool classof(const Value *V) { return (isa<Instruction>(V) && classof(cast<Instruction>(V))) || (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V))); } };
/// PossiblyExactOperator - A udiv or sdiv instruction, which can be marked as
/// "exact", indicating that no bits are destroyed.
class PossiblyExactOperator : public Operator { public: enum { IsExact = (1 << 0) };
private: friend class BinaryOperator; friend class ConstantExpr; void setIsExact(bool B) { SubclassOptionalData = (SubclassOptionalData & ~IsExact) | (B * IsExact); }
public: /// isExact - Test whether this division is known to be exact, with
/// zero remainder.
bool isExact() const { return SubclassOptionalData & IsExact; }
static bool isPossiblyExactOpcode(unsigned OpC) { return OpC == Instruction::SDiv || OpC == Instruction::UDiv || OpC == Instruction::AShr || OpC == Instruction::LShr; } static inline bool classof(const ConstantExpr *CE) { return isPossiblyExactOpcode(CE->getOpcode()); } static inline bool classof(const Instruction *I) { return isPossiblyExactOpcode(I->getOpcode()); } static inline bool classof(const Value *V) { return (isa<Instruction>(V) && classof(cast<Instruction>(V))) || (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V))); } };
/// Convenience struct for specifying and reasoning about fast-math flags.
class FastMathFlags { private: friend class FPMathOperator; unsigned Flags; FastMathFlags(unsigned F) : Flags(F) { }
public: enum { UnsafeAlgebra = (1 << 0), NoNaNs = (1 << 1), NoInfs = (1 << 2), NoSignedZeros = (1 << 3), AllowReciprocal = (1 << 4) };
FastMathFlags() : Flags(0) { }
/// Whether any flag is set
bool any() { return Flags != 0; }
/// Set all the flags to false
void clear() { Flags = 0; }
/// Flag queries
bool noNaNs() { return 0 != (Flags & NoNaNs); } bool noInfs() { return 0 != (Flags & NoInfs); } bool noSignedZeros() { return 0 != (Flags & NoSignedZeros); } bool allowReciprocal() { return 0 != (Flags & AllowReciprocal); } bool unsafeAlgebra() { return 0 != (Flags & UnsafeAlgebra); }
/// Flag setters
void setNoNaNs() { Flags |= NoNaNs; } void setNoInfs() { Flags |= NoInfs; } void setNoSignedZeros() { Flags |= NoSignedZeros; } void setAllowReciprocal() { Flags |= AllowReciprocal; } void setUnsafeAlgebra() { Flags |= UnsafeAlgebra; setNoNaNs(); setNoInfs(); setNoSignedZeros(); setAllowReciprocal(); } };
/// FPMathOperator - Utility class for floating point operations which can have
/// information about relaxed accuracy requirements attached to them.
class FPMathOperator : public Operator { private: friend class Instruction;
void setHasUnsafeAlgebra(bool B) { SubclassOptionalData = (SubclassOptionalData & ~FastMathFlags::UnsafeAlgebra) | (B * FastMathFlags::UnsafeAlgebra);
// Unsafe algebra implies all the others
if (B) { setHasNoNaNs(true); setHasNoInfs(true); setHasNoSignedZeros(true); setHasAllowReciprocal(true); } } void setHasNoNaNs(bool B) { SubclassOptionalData = (SubclassOptionalData & ~FastMathFlags::NoNaNs) | (B * FastMathFlags::NoNaNs); } void setHasNoInfs(bool B) { SubclassOptionalData = (SubclassOptionalData & ~FastMathFlags::NoInfs) | (B * FastMathFlags::NoInfs); } void setHasNoSignedZeros(bool B) { SubclassOptionalData = (SubclassOptionalData & ~FastMathFlags::NoSignedZeros) | (B * FastMathFlags::NoSignedZeros); } void setHasAllowReciprocal(bool B) { SubclassOptionalData = (SubclassOptionalData & ~FastMathFlags::AllowReciprocal) | (B * FastMathFlags::AllowReciprocal); }
/// Convenience function for setting all the fast-math flags
void setFastMathFlags(FastMathFlags FMF) { SubclassOptionalData |= FMF.Flags; }
public: /// Test whether this operation is permitted to be
/// algebraically transformed, aka the 'A' fast-math property.
bool hasUnsafeAlgebra() const { return (SubclassOptionalData & FastMathFlags::UnsafeAlgebra) != 0; }
/// Test whether this operation's arguments and results are to be
/// treated as non-NaN, aka the 'N' fast-math property.
bool hasNoNaNs() const { return (SubclassOptionalData & FastMathFlags::NoNaNs) != 0; }
/// Test whether this operation's arguments and results are to be
/// treated as NoN-Inf, aka the 'I' fast-math property.
bool hasNoInfs() const { return (SubclassOptionalData & FastMathFlags::NoInfs) != 0; }
/// Test whether this operation can treat the sign of zero
/// as insignificant, aka the 'S' fast-math property.
bool hasNoSignedZeros() const { return (SubclassOptionalData & FastMathFlags::NoSignedZeros) != 0; }
/// Test whether this operation is permitted to use
/// reciprocal instead of division, aka the 'R' fast-math property.
bool hasAllowReciprocal() const { return (SubclassOptionalData & FastMathFlags::AllowReciprocal) != 0; }
/// Convenience function for getting all the fast-math flags
FastMathFlags getFastMathFlags() const { return FastMathFlags(SubclassOptionalData); }
/// \brief Get the maximum error permitted by this operation in ULPs. An
/// accuracy of 0.0 means that the operation should be performed with the
/// default precision.
float getFPAccuracy() const;
static inline bool classof(const Instruction *I) { return I->getType()->isFPOrFPVectorTy(); } static inline bool classof(const Value *V) { return isa<Instruction>(V) && classof(cast<Instruction>(V)); } };
/// ConcreteOperator - A helper template for defining operators for individual
/// opcodes.
template<typename SuperClass, unsigned Opc> class ConcreteOperator : public SuperClass { public: static inline bool classof(const Instruction *I) { return I->getOpcode() == Opc; } static inline bool classof(const ConstantExpr *CE) { return CE->getOpcode() == Opc; } static inline bool classof(const Value *V) { return (isa<Instruction>(V) && classof(cast<Instruction>(V))) || (isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V))); } };
class AddOperator : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Add> { }; class SubOperator : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Sub> { }; class MulOperator : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Mul> { }; class ShlOperator : public ConcreteOperator<OverflowingBinaryOperator, Instruction::Shl> { };
class SDivOperator : public ConcreteOperator<PossiblyExactOperator, Instruction::SDiv> { }; class UDivOperator : public ConcreteOperator<PossiblyExactOperator, Instruction::UDiv> { }; class AShrOperator : public ConcreteOperator<PossiblyExactOperator, Instruction::AShr> { }; class LShrOperator : public ConcreteOperator<PossiblyExactOperator, Instruction::LShr> { };
class GEPOperator : public ConcreteOperator<Operator, Instruction::GetElementPtr> { enum { IsInBounds = (1 << 0) };
friend class GetElementPtrInst; friend class ConstantExpr; void setIsInBounds(bool B) { SubclassOptionalData = (SubclassOptionalData & ~IsInBounds) | (B * IsInBounds); }
public: /// isInBounds - Test whether this is an inbounds GEP, as defined
/// by LangRef.html.
bool isInBounds() const { return SubclassOptionalData & IsInBounds; }
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.
Type *getPointerOperandType() const { return getPointerOperand()->getType(); }
/// getPointerAddressSpace - Method to return the address space of the
/// pointer operand.
unsigned getPointerAddressSpace() const { return cast<PointerType>(getPointerOperandType())->getAddressSpace(); }
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 (ConstantInt *C = dyn_cast<ConstantInt>(I)) if (C->isZero()) continue; return false; } return true; }
/// hasAllConstantIndices - Return true if all of the indices of this GEP are
/// constant integers. If so, the result pointer and the first operand have
/// a constant offset between them.
bool hasAllConstantIndices() const { for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) { if (!isa<ConstantInt>(I)) return false; } return true; }
/// \brief Accumulate the constant address offset of this GEP if possible.
///
/// This routine accepts an APInt into which it will accumulate the constant
/// offset of this GEP if the GEP is in fact constant. If the GEP is not
/// all-constant, it returns false and the value of the offset APInt is
/// undefined (it is *not* preserved!). The APInt passed into this routine
/// must be at least as wide as the IntPtr type for the address space of
/// the base GEP pointer.
bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const { assert(Offset.getBitWidth() == DL.getPointerSizeInBits(getPointerAddressSpace()) && "The offset must have exactly as many bits as our pointer.");
for (gep_type_iterator GTI = gep_type_begin(this), GTE = gep_type_end(this); GTI != GTE; ++GTI) { ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand()); if (!OpC) return false; if (OpC->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (StructType *STy = dyn_cast<StructType>(*GTI)) { unsigned ElementIdx = OpC->getZExtValue(); const StructLayout *SL = DL.getStructLayout(STy); Offset += APInt(Offset.getBitWidth(), SL->getElementOffset(ElementIdx)); continue; }
// For array or vector indices, scale the index by the size of the type.
APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth()); Offset += Index * APInt(Offset.getBitWidth(), DL.getTypeAllocSize(GTI.getIndexedType())); } return true; }
};
} // End llvm namespace
#endif
|