llvm-6502/utils/TableGen/InstrSelectorEmitter.h

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//===- InstrInfoEmitter.h - Generate a Instruction Set Desc. ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend is responsible for emitting a description of the target
// instruction set for the code generator.
//
//===----------------------------------------------------------------------===//
#ifndef INSTRSELECTOR_EMITTER_H
#define INSTRSELECTOR_EMITTER_H
#include "TableGenBackend.h"
#include "CodeGenWrappers.h"
#include <vector>
#include <map>
#include <cassert>
namespace llvm {
class DagInit;
class Init;
class InstrSelectorEmitter;
/// NodeType - Represents Information parsed from the DagNode entries.
///
struct NodeType {
enum ArgResultTypes {
Any, // No constraint on type
Val, // A non-void type
Arg0, // Value matches the type of Arg0
Arg1, // Value matches the type of Arg1
Ptr, // Tree node is the type of the target pointer
I8, // Always bool
Void, // Tree node always returns void
};
ArgResultTypes ResultType;
std::vector<ArgResultTypes> ArgTypes;
NodeType(ArgResultTypes RT, std::vector<ArgResultTypes> &AT) : ResultType(RT){
AT.swap(ArgTypes);
}
NodeType() : ResultType(Val) {}
NodeType(const NodeType &N) : ResultType(N.ResultType), ArgTypes(N.ArgTypes){}
static ArgResultTypes Translate(Record *R);
};
/// TreePatternNode - Represent a node of the tree patterns.
///
class TreePatternNode {
/// Operator - The operation that this node represents... this is null if this
/// is a leaf.
Record *Operator;
/// Type - The inferred value type...
///
MVT::ValueType Type;
/// Children - If this is not a leaf (Operator != 0), this is the subtrees
/// that we contain.
std::vector<std::pair<TreePatternNode*, std::string> > Children;
/// Value - If this node is a leaf, this indicates what the thing is.
///
Init *Value;
public:
TreePatternNode(Record *o, const std::vector<std::pair<TreePatternNode*,
std::string> > &c)
: Operator(o), Type(MVT::Other), Children(c), Value(0) {}
TreePatternNode(Init *V) : Operator(0), Type(MVT::Other), Value(V) {}
Record *getOperator() const {
assert(Operator && "This is a leaf node!");
return Operator;
}
MVT::ValueType getType() const { return Type; }
void setType(MVT::ValueType T) { Type = T; }
bool isLeaf() const { return Operator == 0; }
unsigned getNumChildren() const { return Children.size(); }
TreePatternNode *getChild(unsigned c) const {
assert(Operator != 0 && "This is a leaf node!");
assert(c < Children.size() && "Child access out of range!");
return Children[c].first;
}
const std::string &getChildName(unsigned c) const {
assert(Operator != 0 && "This is a leaf node!");
assert(c < Children.size() && "Child access out of range!");
return Children[c].second;
}
Init *getValue() const {
assert(Operator == 0 && "This is not a leaf node!");
return Value;
}
/// getValueRecord - Returns the value of this tree node as a record. For now
/// we only allow DefInit's as our leaf values, so this is used.
Record *getValueRecord() const;
/// clone - Make a copy of this tree and all of its children.
///
TreePatternNode *clone() const;
void dump() const;
/// InstantiateNonterminals - If this pattern refers to any nonterminals which
/// are not themselves completely resolved, clone the nonterminal and resolve
/// it with the using context we provide.
void InstantiateNonterminals(InstrSelectorEmitter &ISE);
/// UpdateNodeType - Set the node type of N to VT if VT contains information.
/// If N already contains a conflicting type, then throw an exception. This
/// returns true if any information was updated.
///
bool updateNodeType(MVT::ValueType VT, const std::string &RecName);
};
std::ostream &operator<<(std::ostream &OS, const TreePatternNode &N);
/// Pattern - Represent a pattern of one form or another. Currently, three
/// types of patterns are possible: Instruction's, Nonterminals, and Expanders.
///
struct Pattern {
enum PatternType {
Nonterminal, Instruction, Expander
};
private:
/// PTy - The type of pattern this is.
///
PatternType PTy;
/// Tree - The tree pattern which corresponds to this pattern. Note that if
/// there was a (set) node on the outside level that it has been stripped off.
///
TreePatternNode *Tree;
/// Result - If this is an instruction or expander pattern, this is the
/// register result, specified with a (set) in the pattern.
///
std::string ResultName; // The name of the result value...
TreePatternNode *ResultNode; // The leaf node for the result register...
/// TheRecord - The actual TableGen record corresponding to this pattern.
///
Record *TheRecord;
/// Resolved - This is true of the pattern is useful in practice. In
/// particular, some non-terminals will have non-resolvable types. When a
/// user of the non-terminal is later found, they will have inferred a type
/// for the result of the non-terminal, which cause a clone of an unresolved
/// nonterminal to be made which is "resolved".
///
bool Resolved;
/// Args - This is a list of all of the arguments to this pattern, which are
/// the non-void leaf nodes in this pattern.
std::vector<std::pair<TreePatternNode*, std::string> > Args;
/// ISE - the instruction selector emitter coordinating this madness.
///
InstrSelectorEmitter &ISE;
public:
/// Pattern constructor - Parse the specified DagInitializer into the current
/// record.
Pattern(PatternType pty, DagInit *RawPat, Record *TheRec,
InstrSelectorEmitter &ise);
/// Pattern - Constructor used for cloning nonterminal patterns
Pattern(TreePatternNode *tree, Record *rec, bool res,
InstrSelectorEmitter &ise)
: PTy(Nonterminal), Tree(tree), ResultNode(0), TheRecord(rec),
Resolved(res), ISE(ise) {
calculateArgs(Tree, "");
}
/// getPatternType - Return what flavor of Record this pattern originated from
///
PatternType getPatternType() const { return PTy; }
/// getTree - Return the tree pattern which corresponds to this pattern.
///
TreePatternNode *getTree() const { return Tree; }
Record *getResult() const {
return ResultNode ? ResultNode->getValueRecord() : 0;
}
const std::string &getResultName() const { return ResultName; }
TreePatternNode *getResultNode() const { return ResultNode; }
/// getRecord - Return the actual TableGen record corresponding to this
/// pattern.
///
Record *getRecord() const { return TheRecord; }
unsigned getNumArgs() const { return Args.size(); }
TreePatternNode *getArg(unsigned i) const {
assert(i < Args.size() && "Argument reference out of range!");
return Args[i].first;
}
Record *getArgRec(unsigned i) const {
return getArg(i)->getValueRecord();
}
Init *getArgVal(unsigned i) const {
return getArg(i)->getValue();
}
const std::string &getArgName(unsigned i) const {
assert(i < Args.size() && "Argument reference out of range!");
return Args[i].second;
}
bool isResolved() const { return Resolved; }
/// InferAllTypes - Runs the type inference engine on the current pattern,
/// stopping when nothing can be inferred, then updating the Resolved field.
void InferAllTypes();
/// InstantiateNonterminals - If this pattern refers to any nonterminals which
/// are not themselves completely resolved, clone the nonterminal and resolve
/// it with the using context we provide.
void InstantiateNonterminals() {
Tree->InstantiateNonterminals(ISE);
}
/// clone - This method is used to make an exact copy of the current pattern,
/// then change the "TheRecord" instance variable to the specified record.
///
Pattern *clone(Record *R) const;
/// error - Throw an exception, prefixing it with information about this
/// pattern.
void error(const std::string &Msg) const;
/// getSlotName - If this is a leaf node, return the slot name that the
/// operand will update.
std::string getSlotName() const;
static std::string getSlotName(Record *R);
void dump() const;
private:
void calculateArgs(TreePatternNode *N, const std::string &Name);
MVT::ValueType getIntrinsicType(Record *R) const;
TreePatternNode *ParseTreePattern(DagInit *DI);
bool InferTypes(TreePatternNode *N, bool &MadeChange);
};
std::ostream &operator<<(std::ostream &OS, const Pattern &P);
/// PatternOrganizer - This class represents all of the patterns which are
/// useful for the instruction selector, neatly catagorized in a hierarchical
/// structure.
struct PatternOrganizer {
/// PatternsForNode - The list of patterns which can produce a value of a
/// particular slot type, given a particular root node in the tree. All of
/// the patterns in this vector produce the same value type and have the same
/// root DAG node.
typedef std::vector<Pattern*> PatternsForNode;
/// NodesForSlot - This map keeps track of all of the root DAG nodes which can
/// lead to the production of a value for this slot. All of the patterns in
/// this data structure produces values of the same slot.
typedef std::map<Record*, PatternsForNode> NodesForSlot;
/// AllPatterns - This data structure contains all patterns in the instruction
/// selector.
std::map<std::string, NodesForSlot> AllPatterns;
// Forwarding functions...
typedef std::map<std::string, NodesForSlot>::iterator iterator;
iterator begin() { return AllPatterns.begin(); }
iterator end() { return AllPatterns.end(); }
/// addPattern - Add the specified pattern to the appropriate location in the
/// collection.
void addPattern(Pattern *P);
};
/// InstrSelectorEmitter - The top-level class which coordinates construction
/// and emission of the instruction selector.
///
class InstrSelectorEmitter : public TableGenBackend {
RecordKeeper &Records;
CodeGenTarget Target;
std::map<Record*, NodeType> NodeTypes;
/// Patterns - a list of all of the patterns defined by the target description
///
std::map<Record*, Pattern*> Patterns;
/// InstantiatedNTs - A data structure to keep track of which nonterminals
/// have been instantiated already...
///
std::map<std::pair<Pattern*,MVT::ValueType>, Record*> InstantiatedNTs;
/// ComputableValues - This map indicates which patterns can be used to
/// generate a value that is used by the selector. The keys of this map
/// implicitly define the values that are used by the selector.
///
PatternOrganizer ComputableValues;
public:
InstrSelectorEmitter(RecordKeeper &R) : Records(R) {}
// run - Output the instruction set description, returning true on failure.
void run(std::ostream &OS);
const CodeGenTarget &getTarget() const { return Target; }
std::map<Record*, NodeType> &getNodeTypes() { return NodeTypes; }
const NodeType &getNodeType(Record *R) const {
std::map<Record*, NodeType>::const_iterator I = NodeTypes.find(R);
assert(I != NodeTypes.end() && "Unknown node type!");
return I->second;
}
/// getPattern - return the pattern corresponding to the specified record, or
/// null if there is none.
Pattern *getPattern(Record *R) const {
std::map<Record*, Pattern*>::const_iterator I = Patterns.find(R);
return I != Patterns.end() ? I->second : 0;
}
/// ReadNonterminal - This method parses the specified record as a
/// nonterminal, but only if it hasn't been read in already.
Pattern *ReadNonterminal(Record *R);
/// InstantiateNonterminal - This method takes the nonterminal specified by
/// NT, which should not be completely resolved, clones it, applies ResultTy
/// to its root, then runs the type inference stuff on it. This should
/// produce a newly resolved nonterminal, which we make a record for and
/// return. To be extra fancy and efficient, this only makes one clone for
/// each type it is instantiated with.
Record *InstantiateNonterminal(Pattern *NT, MVT::ValueType ResultTy);
private:
// ReadNodeTypes - Read in all of the node types in the current RecordKeeper,
// turning them into the more accessible NodeTypes data structure.
void ReadNodeTypes();
// ReadNonTerminals - Read in all nonterminals and incorporate them into our
// pattern database.
void ReadNonterminals();
// ReadInstructionPatterns - Read in all subclasses of Instruction, and
// process those with a useful Pattern field.
void ReadInstructionPatterns();
// ReadExpanderPatterns - Read in all of the expanded patterns.
void ReadExpanderPatterns();
// InstantiateNonterminals - Instantiate any unresolved nonterminals with
// information from the context that they are used in.
void InstantiateNonterminals();
// CalculateComputableValues - Fill in the ComputableValues map through
// analysis of the patterns we are playing with.
void CalculateComputableValues();
// EmitMatchCosters - Given a list of patterns, which all have the same root
// pattern operator, emit an efficient decision tree to decide which one to
// pick. This is structured this way to avoid reevaluations of non-obvious
// subexpressions.
void EmitMatchCosters(std::ostream &OS,
const std::vector<std::pair<Pattern*, TreePatternNode*> > &Patterns,
const std::string &VarPrefix, unsigned Indent);
/// PrintExpanderOperand - Print out Arg as part of the instruction emission
/// process for the expander pattern P. This argument may be referencing some
/// values defined in P, or may just be physical register references or
/// something like that. If PrintArg is true, we are printing out arguments
/// to the BuildMI call. If it is false, we are printing the result register
/// name.
void PrintExpanderOperand(Init *Arg, const std::string &NameVar,
TreePatternNode *ArgDecl, Pattern *P,
bool PrintArg, std::ostream &OS);
};
} // End llvm namespace
#endif