llvm-6502/utils/TableGen/CodeGenRegisters.h

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//===- CodeGenRegisters.h - Register and RegisterClass Info -----*- 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 structures to encapsulate information gleaned from the
// target register and register class definitions.
//
//===----------------------------------------------------------------------===//
#ifndef CODEGEN_REGISTERS_H
#define CODEGEN_REGISTERS_H
#include "Record.h"
#include "SetTheory.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SetVector.h"
#include <cstdlib>
#include <map>
#include <string>
#include <set>
#include <vector>
namespace llvm {
class CodeGenRegBank;
/// CodeGenRegister - Represents a register definition.
struct CodeGenRegister {
Record *TheDef;
unsigned EnumValue;
unsigned CostPerUse;
// Map SubRegIndex -> Register.
typedef std::map<Record*, CodeGenRegister*, LessRecord> SubRegMap;
CodeGenRegister(Record *R, unsigned Enum);
const std::string &getName() const;
// Get a map of sub-registers computed lazily.
// This includes unique entries for all sub-sub-registers.
const SubRegMap &getSubRegs(CodeGenRegBank&);
const SubRegMap &getSubRegs() const {
assert(SubRegsComplete && "Must precompute sub-registers");
return SubRegs;
}
// Add sub-registers to OSet following a pre-order defined by the .td file.
void addSubRegsPreOrder(SetVector<CodeGenRegister*> &OSet) const;
// List of super-registers in topological order, small to large.
typedef std::vector<CodeGenRegister*> SuperRegList;
// Get the list of super-registers.
// This is only valid after computeDerivedInfo has visited all registers.
const SuperRegList &getSuperRegs() const {
assert(SubRegsComplete && "Must precompute sub-registers");
return SuperRegs;
}
// Order CodeGenRegister pointers by EnumValue.
struct Less {
bool operator()(const CodeGenRegister *A,
const CodeGenRegister *B) const {
return A->EnumValue < B->EnumValue;
}
};
// Canonically ordered set.
typedef std::set<const CodeGenRegister*, Less> Set;
private:
bool SubRegsComplete;
SubRegMap SubRegs;
SuperRegList SuperRegs;
};
class CodeGenRegisterClass {
CodeGenRegister::Set Members;
const std::vector<Record*> *Elements;
std::vector<SmallVector<Record*, 16> > AltOrders;
public:
Record *TheDef;
std::string Namespace;
std::vector<MVT::SimpleValueType> VTs;
unsigned SpillSize;
unsigned SpillAlignment;
int CopyCost;
bool Allocatable;
// Map SubRegIndex -> RegisterClass
DenseMap<Record*,Record*> SubRegClasses;
std::string AltOrderSelect;
const std::string &getName() const;
const std::vector<MVT::SimpleValueType> &getValueTypes() const {return VTs;}
unsigned getNumValueTypes() const { return VTs.size(); }
MVT::SimpleValueType getValueTypeNum(unsigned VTNum) const {
if (VTNum < VTs.size())
return VTs[VTNum];
assert(0 && "VTNum greater than number of ValueTypes in RegClass!");
abort();
}
// Return true if this this class contains the register.
bool contains(const CodeGenRegister*) const;
// Returns true if RC is a subclass.
// RC is a sub-class of this class if it is a valid replacement for any
// instruction operand where a register of this classis required. It must
// satisfy these conditions:
//
// 1. All RC registers are also in this.
// 2. The RC spill size must not be smaller than our spill size.
// 3. RC spill alignment must be compatible with ours.
//
bool hasSubClass(const CodeGenRegisterClass *RC) const;
// Returns an ordered list of class members.
// The order of registers is the same as in the .td file.
// No = 0 is the default allocation order, No = 1 is the first alternative.
ArrayRef<Record*> getOrder(unsigned No = 0) const {
if (No == 0)
return *Elements;
else
return AltOrders[No - 1];
}
// Return the total number of allocation orders available.
unsigned getNumOrders() const { return 1 + AltOrders.size(); }
CodeGenRegisterClass(CodeGenRegBank&, Record *R);
};
// CodeGenRegBank - Represent a target's registers and the relations between
// them.
class CodeGenRegBank {
RecordKeeper &Records;
SetTheory Sets;
std::vector<Record*> SubRegIndices;
unsigned NumNamedIndices;
std::vector<CodeGenRegister*> Registers;
DenseMap<Record*, CodeGenRegister*> Def2Reg;
std::vector<CodeGenRegisterClass> RegClasses;
DenseMap<Record*, CodeGenRegisterClass*> Def2RC;
// Composite SubRegIndex instances.
// Map (SubRegIndex, SubRegIndex) -> SubRegIndex.
typedef DenseMap<std::pair<Record*, Record*>, Record*> CompositeMap;
CompositeMap Composite;
// Populate the Composite map from sub-register relationships.
void computeComposites();
public:
CodeGenRegBank(RecordKeeper&);
SetTheory &getSets() { return Sets; }
// Sub-register indices. The first NumNamedIndices are defined by the user
// in the .td files. The rest are synthesized such that all sub-registers
// have a unique name.
const std::vector<Record*> &getSubRegIndices() { return SubRegIndices; }
unsigned getNumNamedIndices() { return NumNamedIndices; }
// Map a SubRegIndex Record to its enum value.
unsigned getSubRegIndexNo(Record *idx);
// Find or create a sub-register index representing the A+B composition.
Record *getCompositeSubRegIndex(Record *A, Record *B, bool create = false);
const std::vector<CodeGenRegister*> &getRegisters() { return Registers; }
// Find a register from its Record def.
CodeGenRegister *getReg(Record*);
const std::vector<CodeGenRegisterClass> &getRegClasses() {
return RegClasses;
}
// Find a register class from its def.
CodeGenRegisterClass *getRegClass(Record*);
/// getRegisterClassForRegister - Find the register class that contains the
/// specified physical register. If the register is not in a register
/// class, return null. If the register is in multiple classes, and the
/// classes have a superset-subset relationship and the same set of types,
/// return the superclass. Otherwise return null.
const CodeGenRegisterClass* getRegClassForRegister(Record *R);
// Computed derived records such as missing sub-register indices.
void computeDerivedInfo();
// Compute full overlap sets for every register. These sets include the
// rarely used aliases that are neither sub nor super-registers.
//
// Map[R1].count(R2) is reflexive and symmetric, but not transitive.
//
// If R1 is a sub-register of R2, Map[R1] is a subset of Map[R2].
void computeOverlaps(std::map<const CodeGenRegister*,
CodeGenRegister::Set> &Map);
};
}
#endif