llvm-6502/include/llvm/IR/Operator.h
2013-09-12 01:07:54 +00:00

479 lines
15 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_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 exactly 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