llvm-6502/include/llvm/CodeGen/InstrForest.h
Chris Lattner 70534ee581 Whoops, this one was needed
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7346 91177308-0d34-0410-b5e6-96231b3b80d8
2003-07-26 23:18:11 +00:00

322 lines
10 KiB
C++

//===-- llvm/CodeGen/InstForest.h ------------------------------*- C++ -*--===//
//
// Purpose:
// Convert SSA graph to instruction trees for instruction selection.
//
// Strategy:
// The basic idea is that we would like to group instructions into a single
// tree if one or more of them might be potentially combined into a single
// complex instruction in the target machine.
// Since this grouping is completely machine-independent, it is as
// aggressive as possible. In particular, we group two instructions
// O and I if:
// (1) Instruction O computes an operand of instruction I, and
// (2) O and I are part of the same basic block, and
// (3) O has only a single use, viz., I.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_INSTRFOREST_H
#define LLVM_CODEGEN_INSTRFOREST_H
#include "llvm/Instruction.h"
#include "Support/hash_map"
class Constant;
class Function;
class InstrTreeNode;
class InstrForest;
//--------------------------------------------------------------------------
// OpLabel values for special-case nodes created for instruction selection.
// All op-labels not defined here are identical to the instruction
// opcode returned by Instruction::getOpcode()
//--------------------------------------------------------------------------
const int InvalidOp = -1;
const int VRegListOp = 97;
const int VRegNodeOp = 98;
const int ConstantNodeOp= 99;
const int LabelNodeOp = 100;
const int RetValueOp = 100 + Instruction::Ret; // 101
const int BrCondOp = 100 + Instruction::Br; // 102
const int BAndOp = 100 + Instruction::And; // 111
const int BOrOp = 100 + Instruction::Or; // 112
const int BXorOp = 100 + Instruction::Xor; // 113
const int BNotOp = 200 + Instruction::Xor; // 213
const int NotOp = 300 + Instruction::Xor; // 313
const int SetCCOp = 100 + Instruction::SetEQ; // 114
const int AllocaN = 100 + Instruction::Alloca; // 122
const int LoadIdx = 100 + Instruction::Load; // 123
const int GetElemPtrIdx= 100 + Instruction::GetElementPtr; // 125
const int ToBoolTy = 100 + Instruction::Cast; // 127
const int ToUByteTy = ToBoolTy + 1;
const int ToSByteTy = ToBoolTy + 2;
const int ToUShortTy = ToBoolTy + 3;
const int ToShortTy = ToBoolTy + 4;
const int ToUIntTy = ToBoolTy + 5;
const int ToIntTy = ToBoolTy + 6;
const int ToULongTy = ToBoolTy + 7;
const int ToLongTy = ToBoolTy + 8;
const int ToFloatTy = ToBoolTy + 9;
const int ToDoubleTy = ToBoolTy + 10;
const int ToArrayTy = ToBoolTy + 11;
const int ToPointerTy = ToBoolTy + 12;
//-------------------------------------------------------------------------
// Data types needed by BURG and implemented by us
//-------------------------------------------------------------------------
typedef int OpLabel;
typedef int StateLabel;
//-------------------------------------------------------------------------
// Declarations of data and functions created by BURG
//-------------------------------------------------------------------------
extern short* burm_nts[];
extern StateLabel burm_label (InstrTreeNode* p);
extern StateLabel burm_state (OpLabel op, StateLabel leftState,
StateLabel rightState);
extern StateLabel burm_rule (StateLabel state, int goalNT);
extern InstrTreeNode** burm_kids (InstrTreeNode* p, int eruleno,
InstrTreeNode* kids[]);
extern void printcover (InstrTreeNode*, int, int);
extern void printtree (InstrTreeNode*);
extern int treecost (InstrTreeNode*, int, int);
extern void printMatches (InstrTreeNode*);
//------------------------------------------------------------------------
// class InstrTreeNode
//
// A single tree node in the instruction tree used for
// instruction selection via BURG.
//------------------------------------------------------------------------
class InstrTreeNode {
InstrTreeNode(const InstrTreeNode &); // DO NOT IMPLEMENT
void operator=(const InstrTreeNode &); // DO NOT IMPLEMENT
public:
enum InstrTreeNodeType { NTInstructionNode,
NTVRegListNode,
NTVRegNode,
NTConstNode,
NTLabelNode };
// BASIC TREE NODE START
InstrTreeNode* LeftChild;
InstrTreeNode* RightChild;
InstrTreeNode* Parent;
OpLabel opLabel;
StateLabel state;
// BASIC TREE NODE END
protected:
InstrTreeNodeType treeNodeType;
Value* val;
public:
InstrTreeNode(InstrTreeNodeType nodeType, Value* _val)
: treeNodeType(nodeType), val(_val) {
LeftChild = RightChild = Parent = 0;
opLabel = InvalidOp;
}
virtual ~InstrTreeNode() {
delete LeftChild;
delete RightChild;
}
InstrTreeNodeType getNodeType () const { return treeNodeType; }
Value* getValue () const { return val; }
inline OpLabel getOpLabel () const { return opLabel; }
inline InstrTreeNode* leftChild() const {
return LeftChild;
}
// If right child is a list node, recursively get its *left* child
inline InstrTreeNode* rightChild() const {
return (!RightChild ? 0 :
(RightChild->getOpLabel() == VRegListOp
? RightChild->LeftChild : RightChild));
}
inline InstrTreeNode *parent() const {
return Parent;
}
void dump(int dumpChildren, int indent) const;
protected:
virtual void dumpNode(int indent) const = 0;
friend class InstrForest;
};
class InstructionNode : public InstrTreeNode {
private:
bool codeIsFoldedIntoParent;
public:
InstructionNode(Instruction *_instr);
Instruction *getInstruction() const {
assert(treeNodeType == NTInstructionNode);
return cast<Instruction>(val);
}
void markFoldedIntoParent() { codeIsFoldedIntoParent = true; }
bool isFoldedIntoParent() { return codeIsFoldedIntoParent; }
// Methods to support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const InstructionNode *N) { return true; }
static inline bool classof(const InstrTreeNode *N) {
return N->getNodeType() == InstrTreeNode::NTInstructionNode;
}
protected:
virtual void dumpNode(int indent) const;
};
class VRegListNode : public InstrTreeNode {
public:
VRegListNode() : InstrTreeNode(NTVRegListNode, 0) {
opLabel = VRegListOp;
}
// Methods to support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const VRegListNode *N) { return true; }
static inline bool classof(const InstrTreeNode *N) {
return N->getNodeType() == InstrTreeNode::NTVRegListNode;
}
protected:
virtual void dumpNode(int indent) const;
};
class VRegNode : public InstrTreeNode {
public:
VRegNode(Value* _val) : InstrTreeNode(NTVRegNode, _val) {
opLabel = VRegNodeOp;
}
// Methods to support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const VRegNode *N) { return true; }
static inline bool classof(const InstrTreeNode *N) {
return N->getNodeType() == InstrTreeNode::NTVRegNode;
}
protected:
virtual void dumpNode(int indent) const;
};
class ConstantNode : public InstrTreeNode {
public:
ConstantNode(Constant *constVal)
: InstrTreeNode(NTConstNode, (Value*)constVal) {
opLabel = ConstantNodeOp;
}
Constant *getConstVal() const { return (Constant*) val;}
// Methods to support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const ConstantNode *N) { return true; }
static inline bool classof(const InstrTreeNode *N) {
return N->getNodeType() == InstrTreeNode::NTConstNode;
}
protected:
virtual void dumpNode(int indent) const;
};
class LabelNode : public InstrTreeNode {
public:
LabelNode(BasicBlock* BB) : InstrTreeNode(NTLabelNode, (Value*)BB) {
opLabel = LabelNodeOp;
}
BasicBlock *getBasicBlock() const { return (BasicBlock*)val;}
// Methods to support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const LabelNode *N) { return true; }
static inline bool classof(const InstrTreeNode *N) {
return N->getNodeType() == InstrTreeNode::NTLabelNode;
}
protected:
virtual void dumpNode(int indent) const;
};
//------------------------------------------------------------------------
// class InstrForest
//
// A forest of instruction trees, usually for a single method.
//
// Methods:
// buildTreesForMethod() Builds the forest of trees for a method
// getTreeNodeForInstr() Returns the tree node for an Instruction
// getRootSet() Returns a set of root nodes for all the trees
//
//------------------------------------------------------------------------
class InstrForest : private hash_map<const Instruction *, InstructionNode*> {
public:
// Use a vector for the root set to get a deterministic iterator
// for stable code generation. Even though we need to erase nodes
// during forest construction, a vector should still be efficient
// because the elements to erase are nearly always near the end.
typedef std::vector<InstructionNode*> RootSet;
typedef RootSet:: iterator root_iterator;
typedef RootSet::const_iterator const_root_iterator;
private:
RootSet treeRoots;
public:
/*ctor*/ InstrForest (Function *F);
/*dtor*/ ~InstrForest ();
inline InstructionNode *getTreeNodeForInstr(Instruction* instr) {
return (*this)[instr];
}
const_root_iterator roots_begin() const { return treeRoots.begin(); }
root_iterator roots_begin() { return treeRoots.begin(); }
const_root_iterator roots_end () const { return treeRoots.end(); }
root_iterator roots_end () { return treeRoots.end(); }
void dump() const;
private:
//
// Private methods for buidling the instruction forest
//
void eraseRoot (InstructionNode* node);
void setLeftChild (InstrTreeNode* parent, InstrTreeNode* child);
void setRightChild(InstrTreeNode* parent, InstrTreeNode* child);
void setParent (InstrTreeNode* child, InstrTreeNode* parent);
void noteTreeNodeForInstr(Instruction* instr, InstructionNode* treeNode);
InstructionNode* buildTreeForInstruction(Instruction* instr);
};
#endif