--- /dev/null
+// $Id$
+//---------------------------------------------------------------------------
+// File:
+// InstrForest.cpp
+//
+// Purpose:
+// Convert SSA graph to instruction trees for instruction selection.
+//
+// Strategy:
+// The key goal is 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, we do it as
+// aggressive as possible to exploit any possible taret instructions.
+// In particular, we group two instructions O and I if:
+// (1) Instruction O computes an operand used by instruction I,
+// and (2) O and I are part of the same basic block,
+// and (3) O has only a single use, viz., I.
+//
+// History:
+// 6/28/01 - Vikram Adve - Created
+//
+//---------------------------------------------------------------------------
+
+
+//************************** System Include Files **************************/
+
+#include <assert.h>
+#include <iostream.h>
+#include <bool.h>
+#include <string>
+
+//*************************** User Include Files ***************************/
+
+#include "llvm/Type.h"
+#include "llvm/Module.h"
+#include "llvm/Method.h"
+#include "llvm/Instruction.h"
+#include "llvm/iTerminators.h"
+#include "llvm/iMemory.h"
+#include "llvm/ConstPoolVals.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/Bytecode/Reader.h"
+#include "llvm/Bytecode/Writer.h"
+#include "llvm/Tools/CommandLine.h"
+#include "llvm/LLC/CompileContext.h"
+#include "llvm/Codegen/MachineInstr.h"
+#include "llvm/Codegen/InstrForest.h"
+
+//************************ Class Implementations **************************/
+
+
+//------------------------------------------------------------------------
+// class InstrTreeNode
+//------------------------------------------------------------------------
+
+
+InstrTreeNode::InstrTreeNode(InstrTreeNodeType nodeType,
+ Value* _val)
+ : treeNodeType(nodeType),
+ val(_val)
+{
+ basicNode.leftChild = NULL;
+ basicNode.rightChild = NULL;
+ basicNode.parent = NULL;
+ basicNode.opLabel = InvalidOp;
+ basicNode.treeNodePtr = this;
+}
+
+InstrTreeNode::~InstrTreeNode()
+{}
+
+
+void
+InstrTreeNode::dump(int dumpChildren,
+ int indent) const
+{
+ this->dumpNode(indent);
+
+ if (dumpChildren)
+ {
+ if (leftChild())
+ leftChild()->dump(dumpChildren, indent+1);
+ if (rightChild())
+ rightChild()->dump(dumpChildren, indent+1);
+ }
+}
+
+
+InstructionNode::InstructionNode(Instruction* _instr)
+ : InstrTreeNode(NTInstructionNode, _instr)
+{
+ OpLabel opLabel = _instr->getOpcode();
+
+ // Distinguish special cases of some instructions such as Ret and Br
+ //
+ if (opLabel == Instruction::Ret && ((ReturnInst*) _instr)->getReturnValue())
+ {
+ opLabel = RetValueOp; // ret(value) operation
+ }
+ else if (opLabel == Instruction::Br && ! ((BranchInst*) _instr)->isUnconditional())
+ {
+ opLabel = BrCondOp; // br(cond) operation
+ }
+ else if (opLabel >= Instruction::SetEQ && opLabel <= Instruction::SetGT)
+ {
+ opLabel = SetCCOp; // common label for all SetCC ops
+ }
+ else if (opLabel == Instruction::Alloca && _instr->getNumOperands() > 0)
+ {
+ opLabel = AllocaN; // Alloca(ptr, N) operation
+ }
+ else if ((opLabel == Instruction::Load ||
+ opLabel == Instruction::GetElementPtr)
+ && ((MemAccessInst*)_instr)->getFirstOffsetIdx() > 0)
+ {
+ opLabel = opLabel + 100; // load/getElem with index vector
+ }
+ else if (opLabel == Instruction::Cast)
+ {
+ const Type* instrValueType = _instr->getType();
+ switch(instrValueType->getPrimitiveID())
+ {
+ case Type::BoolTyID: opLabel = ToBoolTy; break;
+ case Type::UByteTyID: opLabel = ToUByteTy; break;
+ case Type::SByteTyID: opLabel = ToSByteTy; break;
+ case Type::UShortTyID: opLabel = ToUShortTy; break;
+ case Type::ShortTyID: opLabel = ToShortTy; break;
+ case Type::UIntTyID: opLabel = ToUIntTy; break;
+ case Type::IntTyID: opLabel = ToIntTy; break;
+ case Type::ULongTyID: opLabel = ToULongTy; break;
+ case Type::LongTyID: opLabel = ToLongTy; break;
+ case Type::FloatTyID: opLabel = ToFloatTy; break;
+ case Type::DoubleTyID: opLabel = ToDoubleTy; break;
+ default:
+ if (instrValueType->isArrayType())
+ opLabel = ToArrayTy;
+ else if (instrValueType->isPointerType())
+ opLabel = ToPointerTy;
+ else
+ ; // Just use `Cast' opcode otherwise. It's probably ignored.
+ break;
+ }
+ }
+
+ basicNode.opLabel = opLabel;
+}
+
+void
+InstructionNode::reverseBinaryArgumentOrder()
+{
+ assert(getInstruction()->isBinaryOp());
+
+ // switch arguments for the instruction
+ ((BinaryOperator*) getInstruction())->swapOperands();
+
+ // switch arguments for this tree node itself
+ BasicTreeNode* leftCopy = basicNode.leftChild;
+ basicNode.leftChild = basicNode.rightChild;
+ basicNode.rightChild = leftCopy;
+}
+
+void
+InstructionNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << getInstruction()->getOpcodeName();
+
+ const vector<MachineInstr*>& mvec = getInstruction()->getMachineInstrVec();
+ if (mvec.size() > 0)
+ cout << "\tMachine Instructions: ";
+ for (unsigned int i=0; i < mvec.size(); i++)
+ {
+ mvec[i]->dump(0);
+ if (i < mvec.size() - 1)
+ cout << "; ";
+ }
+
+ cout << endl;
+}
+
+
+VRegListNode::VRegListNode()
+ : InstrTreeNode(NTVRegListNode, NULL)
+{
+ basicNode.opLabel = VRegListOp;
+}
+
+void
+VRegListNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "List" << endl;
+}
+
+
+VRegNode::VRegNode(Value* _val)
+ : InstrTreeNode(NTVRegNode, _val)
+{
+ basicNode.opLabel = VRegNodeOp;
+}
+
+void
+VRegNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "VReg " << getValue() << "\t(type "
+ << (int) getValue()->getValueType() << ")" << endl;
+}
+
+
+ConstantNode::ConstantNode(ConstPoolVal* constVal)
+ : InstrTreeNode(NTConstNode, constVal)
+{
+ basicNode.opLabel = ConstantNodeOp;
+}
+
+void
+ConstantNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "Constant " << getValue() << "\t(type "
+ << (int) getValue()->getValueType() << ")" << endl;
+}
+
+
+LabelNode::LabelNode(BasicBlock* _bblock)
+ : InstrTreeNode(NTLabelNode, _bblock)
+{
+ basicNode.opLabel = LabelNodeOp;
+}
+
+void
+LabelNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "Label " << getValue() << endl;
+}
+
+//------------------------------------------------------------------------
+// class InstrForest
+//
+// A forest of instruction trees, usually for a single method.
+//------------------------------------------------------------------------
+
+void
+InstrForest::buildTreesForMethod(Method *method)
+{
+ for (Method::inst_iterator instrIter = method->inst_begin();
+ instrIter != method->inst_end();
+ ++instrIter)
+ {
+ Instruction *instr = *instrIter;
+ if (! instr->isPHINode())
+ (void) this->buildTreeForInstruction(instr);
+ }
+}
+
+
+void
+InstrForest::dump() const
+{
+ for (hash_set<InstructionNode*, ptrHashFunc >::const_iterator
+ treeRootIter = treeRoots.begin();
+ treeRootIter != treeRoots.end();
+ ++treeRootIter)
+ {
+ (*treeRootIter)->dump(/*dumpChildren*/ 1, /*indent*/ 0);
+ }
+}
+
+inline void
+InstrForest::noteTreeNodeForInstr(Instruction* instr,
+ InstructionNode* treeNode)
+{
+ assert(treeNode->getNodeType() == InstrTreeNode::NTInstructionNode);
+ (*this)[instr] = treeNode;
+ treeRoots.insert(treeNode); // mark node as root of a new tree
+}
+
+
+inline void
+InstrForest::setLeftChild(InstrTreeNode* parent, InstrTreeNode* child)
+{
+ parent->basicNode.leftChild = & child->basicNode;
+ child->basicNode.parent = & parent->basicNode;
+ if (child->getNodeType() == InstrTreeNode::NTInstructionNode)
+ treeRoots.erase((InstructionNode*) child); // no longer a tree root
+}
+
+
+inline void
+InstrForest::setRightChild(InstrTreeNode* parent, InstrTreeNode* child)
+{
+ parent->basicNode.rightChild = & child->basicNode;
+ child->basicNode.parent = & parent->basicNode;
+ if (child->getNodeType() == InstrTreeNode::NTInstructionNode)
+ treeRoots.erase((InstructionNode*) child); // no longer a tree root
+}
+
+
+InstructionNode*
+InstrForest::buildTreeForInstruction(Instruction* instr)
+{
+ InstructionNode* treeNode = this->getTreeNodeForInstr(instr);
+ if (treeNode != NULL)
+ {// treeNode has already been constructed for this instruction
+ assert(treeNode->getInstruction() == instr);
+ return treeNode;
+ }
+
+ // Otherwise, create a new tree node for this instruction.
+ //
+ treeNode = new InstructionNode(instr);
+ this->noteTreeNodeForInstr(instr, treeNode);
+
+ // If the instruction has more than 2 instruction operands,
+ // then we will not add any children. This assumes that instructions
+ // like 'call' that have more than 2 instruction operands do not
+ // ever get combined with the instructions that compute the operands.
+ // Note that we only count operands of type instruction and not other
+ // values such as branch labels for a branch or switch instruction.
+ //
+ // To do this efficiently, we'll walk all operands, build treeNodes
+ // for all instruction operands and save them in an array, and then
+ // insert children at the end if there are not more than 2.
+ // As a performance optimization, allocate a child array only
+ // if a fixed array is too small.
+ //
+ int numChildren = 0;
+ const unsigned int MAX_CHILD = 8;
+ static InstrTreeNode* fixedChildArray[MAX_CHILD];
+ InstrTreeNode** childArray =
+ (instr->getNumOperands() > MAX_CHILD)
+ ? new (InstrTreeNode*)[instr->getNumOperands()]
+ : fixedChildArray;
+
+ //
+ // Walk the operands of the instruction
+ //
+ for (Instruction::op_iterator opIter = instr->op_begin();
+ opIter != instr->op_end();
+ ++opIter)
+ {
+ Value* operand = *opIter;
+
+ // Check if the operand is a data value, not an branch label, type,
+ // method or module. If the operand is an address type (i.e., label
+ // or method) that is used in an non-branching operation, e.g., `add'.
+ // that should be considered a data value.
+
+ // Check latter condition here just to simplify the next IF.
+ bool includeAddressOperand =
+ ((operand->getValueType() == Value::BasicBlockVal
+ || operand->getValueType() == Value::MethodVal)
+ && ! instr->isTerminator());
+
+ if (/* (*opIter) != NULL
+ &&*/ includeAddressOperand
+ || operand->getValueType() == Value::InstructionVal
+ || operand->getValueType() == Value::ConstantVal
+ || operand->getValueType() == Value::MethodArgumentVal)
+ {// This operand is a data value
+
+ // An instruction that computes the incoming value is added as a
+ // child of the current instruction if:
+ // the value has only a single use
+ // AND both instructions are in the same basic block
+ // AND the instruction is not a PHI
+ //
+ // (Note that if the value has only a single use (viz., `instr'),
+ // the def of the value can be safely moved just before instr
+ // and therefore it is safe to combine these two instructions.)
+ //
+ // In all other cases, the virtual register holding the value
+ // is used directly, i.e., made a child of the instruction node.
+ //
+ InstrTreeNode* opTreeNode;
+ if (operand->getValueType() == Value::InstructionVal
+ && operand->use_size() == 1
+ && ((Instruction*)operand)->getParent() == instr->getParent()
+ && ! ((Instruction*)operand)->isPHINode())
+ {
+ // Recursively create a treeNode for it.
+ opTreeNode =this->buildTreeForInstruction((Instruction*)operand);
+ }
+ else if (operand->getValueType() == Value::ConstantVal)
+ {
+ // Create a leaf node for a constant
+ opTreeNode = new ConstantNode((ConstPoolVal*) operand);
+ }
+ else
+ {
+ // Create a leaf node for the virtual register
+ opTreeNode = new VRegNode(operand);
+ }
+
+ childArray[numChildren] = opTreeNode;
+ numChildren++;
+ }
+ }
+
+ //--------------------------------------------------------------------
+ // Add any selected operands as children in the tree.
+ // Certain instructions can have more than 2 in some instances (viz.,
+ // a CALL or a memory access -- LOAD, STORE, and GetElemPtr -- to an
+ // array or struct). Make the operands of every such instruction into
+ // a right-leaning binary tree with the operand nodes at the leaves
+ // and VRegList nodes as internal nodes.
+ //--------------------------------------------------------------------
+
+ InstrTreeNode* parent = treeNode; // new VRegListNode();
+ int n;
+
+ if (numChildren > 2)
+ {
+ unsigned instrOpcode = treeNode->getInstruction()->getOpcode();
+ assert(instrOpcode == Instruction::Call ||
+ instrOpcode == Instruction::Load ||
+ instrOpcode == Instruction::Store ||
+ instrOpcode == Instruction::GetElementPtr);
+ }
+
+ // Insert the first child as a direct child
+ if (numChildren >= 1)
+ this->setLeftChild(parent, childArray[0]);
+
+ // Create a list node for children 2 .. N-1, if any
+ for (n = numChildren-1; n >= 2; n--)
+ { // We have more than two children
+ InstrTreeNode* listNode = new VRegListNode();
+ this->setRightChild(parent, listNode);
+ this->setLeftChild(listNode, childArray[numChildren - n]);
+ parent = listNode;
+ }
+
+ // Now insert the last remaining child (if any).
+ if (numChildren >= 2)
+ {
+ assert(n == 1);
+ this->setRightChild(parent, childArray[numChildren - 1]);
+ }
+
+ if (childArray != fixedChildArray)
+ {
+ delete[] childArray;
+ }
+
+ return treeNode;
+}
+
--- /dev/null
+// $Id$ -*-c++-*-
+//***************************************************************************
+// File:
+// InstrSelection.h
+//
+// Purpose:
+//
+// History:
+// 7/02/01 - Vikram Adve - Created
+//***************************************************************************
+
+
+//************************** System Include Files **************************/
+
+#include <assert.h>
+#include <stdio.h>
+#include <iostream.h>
+#include <bool.h>
+#include <string>
+
+//*************************** User Include Files ***************************/
+
+#include "llvm/Method.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/Type.h"
+#include "llvm/iMemory.h"
+#include "llvm/Instruction.h"
+#include "llvm/LLC/CompileContext.h"
+#include "llvm/Codegen/InstrForest.h"
+#include "llvm/Codegen/MachineInstr.h"
+#include "llvm/Codegen/InstrSelection.h"
+
+
+//************************* Forward Declarations ***************************/
+
+static bool SelectInstructionsForTree (BasicTreeNode* treeRoot,
+ int goalnt,
+ CompileContext& ccontext);
+
+
+//******************* Externally Visible Functions *************************/
+
+
+//---------------------------------------------------------------------------
+// Entry point for instruction selection using BURG.
+// Returns true if instruction selection failed, false otherwise.
+//---------------------------------------------------------------------------
+
+bool
+SelectInstructionsForMethod(Method* method,
+ CompileContext& ccontext)
+{
+ bool failed = false;
+
+ InstrForest instrForest;
+ instrForest.buildTreesForMethod(method);
+
+ const hash_set<InstructionNode*, ptrHashFunc>&
+ treeRoots = instrForest.getRootSet();
+
+ //
+ // Invoke BURG instruction selection for each tree
+ //
+ for (hash_set<InstructionNode*, ptrHashFunc >::const_iterator
+ treeRootIter = treeRoots.begin();
+ treeRootIter != treeRoots.end();
+ ++treeRootIter)
+ {
+ BasicTreeNode* basicNode = (*treeRootIter)->getBasicNode();
+
+ // Invoke BURM to label each tree node with a state
+ (void) burm_label(basicNode);
+
+ if (ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT)
+ >= DEBUG_BURG_TREES)
+ {
+ printcover(basicNode, 1, 0);
+ printf("\nCover cost == %d\n\n", treecost(basicNode, 1, 0));
+ printMatches(basicNode);
+ }
+
+ // Then recursively walk the tree to select instructions
+ if (SelectInstructionsForTree(basicNode, /*goalnt*/1, ccontext))
+ {
+ failed = true;
+ break;
+ }
+ }
+
+ if (!failed)
+ {
+ if ( ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT)
+ >= DEBUG_INSTR_TREES)
+ {
+ cout << "\n\n*** Instruction trees for method "
+ << (method->hasName()? method->getName() : "")
+ << endl << endl;
+ instrForest.dump();
+ }
+
+ if (ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT) > 0)
+ PrintMachineInstructions(method, ccontext);
+ }
+
+ return false;
+}
+
+
+//---------------------------------------------------------------------------
+// Function: FoldGetElemChain
+//
+// Purpose:
+// Fold a chain of GetElementPtr instructions into an equivalent
+// (Pointer, IndexVector) pair. Returns the pointer Value, and
+// stores the resulting IndexVector in argument chainIdxVec.
+//---------------------------------------------------------------------------
+
+Value*
+FoldGetElemChain(const InstructionNode* getElemInstrNode,
+ vector<ConstPoolVal*>& chainIdxVec)
+{
+ MemAccessInst* getElemInst = (MemAccessInst*)
+ getElemInstrNode->getInstruction();
+
+ // Initialize return values from the incoming instruction
+ Value* ptrVal = getElemInst->getPtrOperand();
+ chainIdxVec = getElemInst->getIndexVec(); // copies index vector values
+
+ // Now chase the chain of getElementInstr instructions, if any
+ InstrTreeNode* ptrChild = getElemInstrNode->leftChild();
+ while (ptrChild->getOpLabel() == Instruction::GetElementPtr ||
+ ptrChild->getOpLabel() == GetElemPtrIdx)
+ {
+ // Child is a GetElemPtr instruction
+ getElemInst = (MemAccessInst*)
+ ((InstructionNode*) ptrChild)->getInstruction();
+ const vector<ConstPoolVal*>& idxVec = getElemInst->getIndexVec();
+
+ // Get the pointer value out of ptrChild and *prepend* its index vector
+ ptrVal = getElemInst->getPtrOperand();
+ chainIdxVec.insert(chainIdxVec.begin(), idxVec.begin(), idxVec.end());
+
+ ptrChild = ptrChild->leftChild();
+ }
+
+ return ptrVal;
+}
+
+
+void
+PrintMachineInstructions(Method* method,
+ CompileContext& ccontext)
+{
+ cout << "\n" << method->getReturnType()
+ << " \"" << method->getName() << "\"" << endl;
+
+ for (Method::const_iterator bbIter = method->begin();
+ bbIter != method->end();
+ ++bbIter)
+ {
+ BasicBlock* bb = *bbIter;
+ cout << "\n"
+ << (bb->hasName()? bb->getName() : "Label")
+ << " (" << bb << ")" << ":"
+ << endl;
+
+ for (BasicBlock::const_iterator instrIter = bb->begin();
+ instrIter != bb->end();
+ ++instrIter)
+ {
+ Instruction *instr = *instrIter;
+ const MachineCodeForVMInstr& minstrVec = instr->getMachineInstrVec();
+ for (unsigned i=0, N=minstrVec.size(); i < N; i++)
+ cout << "\t" << *minstrVec[i] << endl;
+ }
+ }
+}
+
+//*********************** Private Functions *****************************/
+
+
+//---------------------------------------------------------------------------
+// Function SelectInstructionsForTree
+//
+// Recursively walk the tree to select instructions.
+// Do this top-down so that child instructions can exploit decisions
+// made at the child instructions.
+//
+// E.g., if br(setle(reg,const)) decides the constant is 0 and uses
+// a branch-on-integer-register instruction, then the setle node
+// can use that information to avoid generating the SUBcc instruction.
+//
+// Note that this cannot be done bottom-up because setle must do this
+// only if it is a child of the branch (otherwise, the result of setle
+// may be used by multiple instructions).
+//---------------------------------------------------------------------------
+
+bool
+SelectInstructionsForTree(BasicTreeNode* treeRoot,
+ int goalnt,
+ CompileContext& ccontext)
+{
+ // Use a static vector to avoid allocating a new one per VM instruction
+ static MachineInstr* minstrVec[MAX_INSTR_PER_VMINSTR];
+
+ // Get the rule that matches this node.
+ //
+ int ruleForNode = burm_rule(treeRoot->state, goalnt);
+
+ if (ruleForNode == 0)
+ {
+ cerr << "Could not match instruction tree for instr selection" << endl;
+ return true;
+ }
+
+ // Get this rule's non-terminals and the corresponding child nodes (if any)
+ //
+ short *nts = burm_nts[ruleForNode];
+
+
+ // First, select instructions for the current node and rule.
+ // (If this is a list node, not an instruction, then skip this step).
+ // This function is specific to the target architecture.
+ //
+ if (treeRoot->opLabel != VRegListOp)
+ {
+ InstructionNode* instrNode = (InstructionNode*) MainTreeNode(treeRoot);
+ assert(instrNode->getNodeType() == InstrTreeNode::NTInstructionNode);
+
+ unsigned N = GetInstructionsByRule(instrNode, ruleForNode, nts, ccontext,
+ minstrVec);
+ assert(N <= MAX_INSTR_PER_VMINSTR);
+ for (unsigned i=0; i < N; i++)
+ {
+ assert(minstrVec[i] != NULL);
+ instrNode->getInstruction()->addMachineInstruction(minstrVec[i]);
+ }
+ }
+
+ // Then, recursively compile the child nodes, if any.
+ //
+ if (nts[0])
+ { // i.e., there is at least one kid
+
+ BasicTreeNode* kids[2];
+ int currentRule = ruleForNode;
+ burm_kids(treeRoot, currentRule, kids);
+
+ // First skip over any chain rules so that we don't visit
+ // the current node again.
+ //
+ while (ThisIsAChainRule(currentRule))
+ {
+ currentRule = burm_rule(treeRoot->state, nts[0]);
+ nts = burm_nts[currentRule];
+ burm_kids(treeRoot, currentRule, kids);
+ }
+
+ // Now we have the first non-chain rule so we have found
+ // the actual child nodes. Recursively compile them.
+ //
+ for (int i = 0; nts[i]; i++)
+ {
+ assert(i < 2);
+ InstrTreeNode::InstrTreeNodeType
+ nodeType = MainTreeNode(kids[i])->getNodeType();
+ if (nodeType == InstrTreeNode::NTVRegListNode ||
+ nodeType == InstrTreeNode::NTInstructionNode)
+ {
+ bool failed= SelectInstructionsForTree(kids[i], nts[i],ccontext);
+ if (failed)
+ return true; // failure
+ }
+ }
+ }
+
+ return false; // success
+}
+
--- /dev/null
+LEVEL = ../../..
+
+DIRS =
+
+LIBRARYNAME = select
+
+## List source files in link order
+Source = \
+ InstrSelection.o \
+ MachineInstr.o \
+ InstrForest.o
+
+include $(LEVEL)/Makefile.common
--- /dev/null
+// $Id$
+//***************************************************************************
+// File:
+// MachineInstr.cpp
+//
+// Purpose:
+//
+//
+// Strategy:
+//
+// History:
+// 7/2/01 - Vikram Adve - Created
+//**************************************************************************/
+
+
+//************************** System Include Files **************************/
+
+#include <strstream.h>
+#include <string>
+#include <vector>
+
+//*************************** User Include Files ***************************/
+
+#include "llvm/Type.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/ConstPoolVals.h"
+#include "llvm/Value.h"
+#include "llvm/Instruction.h"
+#include "llvm/Codegen/InstrForest.h"
+#include "llvm/Codegen/MachineInstr.h"
+
+//************************ Class Implementations **************************/
+
+
+bool
+MachineInstrInfo::constantFitsInImmedField(int64_t intValue) const
+{
+ // First, check if opCode has an immed field.
+ bool isSignExtended;
+ uint64_t maxImmedValue = this->maxImmedConstant(isSignExtended);
+ if (maxImmedValue != 0)
+ {
+ // Now check if the constant fits
+ if (intValue <= (int64_t) maxImmedValue &&
+ intValue >= -((int64_t) maxImmedValue+1))
+ return true;
+ }
+
+ return false;
+}
+
+MachineInstr::MachineInstr(MachineOpCode _opCode,
+ OpCodeMask _opCodeMask)
+ : opCode(_opCode),
+ opCodeMask(_opCodeMask),
+ operands(TargetMachineInstrInfo[_opCode].numOperands)
+{
+}
+
+MachineInstr::~MachineInstr()
+{
+}
+
+void
+MachineInstr::SetMachineOperand(unsigned int i,
+ MachineOperand::MachineOperandType operandType,
+ Value* _val)
+{
+ assert(i < TargetMachineInstrInfo[opCode].numOperands);
+ operands[i].Initialize(operandType, _val);
+}
+
+void
+MachineInstr::SetMachineOperand(unsigned int i,
+ MachineOperand::MachineOperandType operandType,
+ int64_t intValue)
+{
+ assert(i < TargetMachineInstrInfo[opCode].numOperands);
+ operands[i].InitializeConst(operandType, intValue);
+}
+
+void
+MachineInstr::SetMachineOperand(unsigned int i,
+ unsigned int regNum)
+{
+ assert(i < TargetMachineInstrInfo[opCode].numOperands);
+ operands[i].InitializeReg(regNum);
+}
+
+void
+MachineInstr::dump(unsigned int indent)
+{
+ for (unsigned i=0; i < indent; i++)
+ cout << " ";
+
+ cout << *this;
+}
+
+ostream&
+operator<< (ostream& os, const MachineInstr& minstr)
+{
+ os << TargetMachineInstrInfo[minstr.opCode].opCodeString;
+
+ for (unsigned i=0, N=minstr.getNumOperands(); i < N; i++)
+ os << "\t" << minstr.getOperand(i);
+
+ return os;
+}
+
+ostream&
+operator<< (ostream& os, const MachineOperand& mop)
+{
+ strstream regInfo;
+ if (mop.machineOperandType == MachineOperand::MO_Register)
+ {
+ if (mop.vregType == MachineOperand::MO_VirtualReg)
+ regInfo << "(val " << mop.value << ")" << ends;
+ else
+ regInfo << "(" << mop.regNum << ")" << ends;
+ }
+ else if (mop.machineOperandType == MachineOperand::MO_CCRegister)
+ regInfo << "(val " << mop.value << ")" << ends;
+
+ switch(mop.machineOperandType)
+ {
+ case MachineOperand::MO_Register:
+ os << "%reg" << regInfo.str();
+ free(regInfo.str());
+ break;
+
+ case MachineOperand::MO_CCRegister:
+ os << "%ccreg" << regInfo.str();
+ free(regInfo.str());
+ break;
+
+ case MachineOperand::MO_SignExtendedImmed:
+ os << mop.immedVal;
+ break;
+
+ case MachineOperand::MO_UnextendedImmed:
+ os << mop.immedVal;
+ break;
+
+ case MachineOperand::MO_PCRelativeDisp:
+ os << "%disp(label " << mop.value << ")";
+ break;
+
+ default:
+ assert(0 && "Unrecognized operand type");
+ break;
+ }
+
+ return os;
+}
+
+
+//---------------------------------------------------------------------------
+// Target-independent utility routines for creating machine instructions
+//---------------------------------------------------------------------------
+
+
+//------------------------------------------------------------------------
+// Function Set2OperandsFromInstr
+// Function Set3OperandsFromInstr
+//
+// For the common case of 2- and 3-operand arithmetic/logical instructions,
+// set the m/c instr. operands directly from the VM instruction's operands.
+// Check whether the first or second operand is 0 and can use a dedicated "0" register.
+// Check whether the second operand should use an immediate field or register.
+// (First and third operands are never immediates for such instructions.)
+//
+// Arguments:
+// canDiscardResult: Specifies that the result operand can be discarded
+// by using the dedicated "0"
+//
+// op1position, op2position and resultPosition: Specify in which position
+// in the machine instruction the 3 operands (arg1, arg2
+// and result) should go.
+//
+// RETURN VALUE: unsigned int flags, where
+// flags & 0x01 => operand 1 is constant and needs a register
+// flags & 0x02 => operand 2 is constant and needs a register
+//------------------------------------------------------------------------
+
+void
+Set2OperandsFromInstr(MachineInstr* minstr,
+ InstructionNode* vmInstrNode,
+ const TargetMachine& targetMachine,
+ bool canDiscardResult,
+ int op1Position,
+ int resultPosition)
+{
+ Set3OperandsFromInstr(minstr, vmInstrNode, targetMachine,
+ canDiscardResult, op1Position,
+ /*op2Position*/ -1, resultPosition);
+}
+
+
+unsigned
+Set3OperandsFromInstrJUNK(MachineInstr* minstr,
+ InstructionNode* vmInstrNode,
+ const TargetMachine& targetMachine,
+ bool canDiscardResult,
+ int op1Position,
+ int op2Position,
+ int resultPosition)
+{
+ assert(op1Position >= 0);
+ assert(resultPosition >= 0);
+
+ unsigned returnFlags = 0x0;
+
+ // Check if operand 1 is 0 and if so, try to use the register that gives 0, if any.
+ Value* op1Value = vmInstrNode->leftChild()->getValue();
+ bool isValidConstant;
+ int64_t intValue = GetConstantValueAsSignedInt(op1Value, isValidConstant);
+ if (isValidConstant && intValue == 0 && targetMachine.zeroRegNum >= 0)
+ minstr->SetMachineOperand(op1Position, /*regNum*/ targetMachine.zeroRegNum);
+ else
+ {
+ if (op1Value->getValueType() == Value::ConstantVal)
+ {// value is constant and must be loaded from constant pool
+ returnFlags = returnFlags | (1 << op1Position);
+ }
+ minstr->SetMachineOperand(op1Position, MachineOperand::MO_Register,
+ op1Value);
+ }
+
+ // Check if operand 2 (if any) fits in the immediate field of the instruction,
+ // of if it is 0 and can use a dedicated machine register
+ if (op2Position >= 0)
+ {
+ Value* op2Value = vmInstrNode->rightChild()->getValue();
+ int64_t immedValue;
+ MachineOperand::VirtualRegisterType vregType;
+ unsigned int machineRegNum;
+
+ MachineOperand::MachineOperandType
+ op2type = ChooseRegOrImmed(op2Value, minstr->getOpCode(),targetMachine,
+ /*canUseImmed*/ true,
+ vregType, machineRegNum, immedValue);
+
+ if (op2type == MachineOperand::MO_Register)
+ {
+ if (vregType == MachineOperand::MO_MachineReg)
+ minstr->SetMachineOperand(op2Position, machineRegNum);
+ else
+ {
+ if (op2Value->getValueType() == Value::ConstantVal)
+ {// value is constant and must be loaded from constant pool
+ returnFlags = returnFlags | (1 << op2Position);
+ }
+ minstr->SetMachineOperand(op2Position, op2type, op2Value);
+ }
+ }
+ else
+ minstr->SetMachineOperand(op2Position, op2type, immedValue);
+ }
+
+ // If operand 3 (result) can be discarded, use a dead register if one exists
+ if (canDiscardResult && targetMachine.zeroRegNum >= 0)
+ minstr->SetMachineOperand(resultPosition, targetMachine.zeroRegNum);
+ else
+ minstr->SetMachineOperand(resultPosition, MachineOperand::MO_Register,
+ vmInstrNode->getValue());
+
+ return returnFlags;
+}
+
+
+void
+Set3OperandsFromInstr(MachineInstr* minstr,
+ InstructionNode* vmInstrNode,
+ const TargetMachine& targetMachine,
+ bool canDiscardResult,
+ int op1Position,
+ int op2Position,
+ int resultPosition)
+{
+ assert(op1Position >= 0);
+ assert(resultPosition >= 0);
+
+ // operand 1
+ minstr->SetMachineOperand(op1Position, MachineOperand::MO_Register,
+ vmInstrNode->leftChild()->getValue());
+
+ // operand 2 (if any)
+ if (op2Position >= 0)
+ minstr->SetMachineOperand(op2Position, MachineOperand::MO_Register,
+ vmInstrNode->rightChild()->getValue());
+
+ // result operand: if it can be discarded, use a dead register if one exists
+ if (canDiscardResult && targetMachine.zeroRegNum >= 0)
+ minstr->SetMachineOperand(resultPosition, targetMachine.zeroRegNum);
+ else
+ minstr->SetMachineOperand(resultPosition, MachineOperand::MO_Register,
+ vmInstrNode->getValue());
+}
+
+
+MachineOperand::MachineOperandType
+ChooseRegOrImmed(Value* val,
+ MachineOpCode opCode,
+ const TargetMachine& targetMachine,
+ bool canUseImmed,
+ MachineOperand::VirtualRegisterType& getVRegType,
+ unsigned int& getMachineRegNum,
+ int64_t& getImmedValue)
+{
+ MachineOperand::MachineOperandType opType = MachineOperand::MO_Register;
+ getVRegType = MachineOperand::MO_VirtualReg;
+ getMachineRegNum = 0;
+ getImmedValue = 0;
+
+ // Check for the common case first: argument is not constant
+ //
+ if (val->getValueType() != Value::ConstantVal)
+ return opType;
+
+ // Now get the constant value and check if it fits in the IMMED field.
+ // Take advantage of the fact that the max unsigned value will rarely
+ // fit into any IMMED field and ignore that case (i.e., cast smaller
+ // unsigned constants to signed).
+ //
+ bool isValidConstant;
+ int64_t intValue = GetConstantValueAsSignedInt(val, isValidConstant);
+
+ if (isValidConstant)
+ {
+ if (intValue == 0 && targetMachine.zeroRegNum >= 0)
+ {
+ getVRegType = MachineOperand::MO_MachineReg;
+ getMachineRegNum = targetMachine.zeroRegNum;
+ }
+ else if (canUseImmed &&
+ targetMachine.machineInstrInfo[opCode].constantFitsInImmedField(intValue))
+ {
+ opType = MachineOperand::MO_SignExtendedImmed;
+ getImmedValue = intValue;
+ }
+ }
+
+ return opType;
+}
--- /dev/null
+// $Id$
+//---------------------------------------------------------------------------
+// File:
+// InstrForest.cpp
+//
+// Purpose:
+// Convert SSA graph to instruction trees for instruction selection.
+//
+// Strategy:
+// The key goal is 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, we do it as
+// aggressive as possible to exploit any possible taret instructions.
+// In particular, we group two instructions O and I if:
+// (1) Instruction O computes an operand used by instruction I,
+// and (2) O and I are part of the same basic block,
+// and (3) O has only a single use, viz., I.
+//
+// History:
+// 6/28/01 - Vikram Adve - Created
+//
+//---------------------------------------------------------------------------
+
+
+//************************** System Include Files **************************/
+
+#include <assert.h>
+#include <iostream.h>
+#include <bool.h>
+#include <string>
+
+//*************************** User Include Files ***************************/
+
+#include "llvm/Type.h"
+#include "llvm/Module.h"
+#include "llvm/Method.h"
+#include "llvm/Instruction.h"
+#include "llvm/iTerminators.h"
+#include "llvm/iMemory.h"
+#include "llvm/ConstPoolVals.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/Bytecode/Reader.h"
+#include "llvm/Bytecode/Writer.h"
+#include "llvm/Tools/CommandLine.h"
+#include "llvm/LLC/CompileContext.h"
+#include "llvm/Codegen/MachineInstr.h"
+#include "llvm/Codegen/InstrForest.h"
+
+//************************ Class Implementations **************************/
+
+
+//------------------------------------------------------------------------
+// class InstrTreeNode
+//------------------------------------------------------------------------
+
+
+InstrTreeNode::InstrTreeNode(InstrTreeNodeType nodeType,
+ Value* _val)
+ : treeNodeType(nodeType),
+ val(_val)
+{
+ basicNode.leftChild = NULL;
+ basicNode.rightChild = NULL;
+ basicNode.parent = NULL;
+ basicNode.opLabel = InvalidOp;
+ basicNode.treeNodePtr = this;
+}
+
+InstrTreeNode::~InstrTreeNode()
+{}
+
+
+void
+InstrTreeNode::dump(int dumpChildren,
+ int indent) const
+{
+ this->dumpNode(indent);
+
+ if (dumpChildren)
+ {
+ if (leftChild())
+ leftChild()->dump(dumpChildren, indent+1);
+ if (rightChild())
+ rightChild()->dump(dumpChildren, indent+1);
+ }
+}
+
+
+InstructionNode::InstructionNode(Instruction* _instr)
+ : InstrTreeNode(NTInstructionNode, _instr)
+{
+ OpLabel opLabel = _instr->getOpcode();
+
+ // Distinguish special cases of some instructions such as Ret and Br
+ //
+ if (opLabel == Instruction::Ret && ((ReturnInst*) _instr)->getReturnValue())
+ {
+ opLabel = RetValueOp; // ret(value) operation
+ }
+ else if (opLabel == Instruction::Br && ! ((BranchInst*) _instr)->isUnconditional())
+ {
+ opLabel = BrCondOp; // br(cond) operation
+ }
+ else if (opLabel >= Instruction::SetEQ && opLabel <= Instruction::SetGT)
+ {
+ opLabel = SetCCOp; // common label for all SetCC ops
+ }
+ else if (opLabel == Instruction::Alloca && _instr->getNumOperands() > 0)
+ {
+ opLabel = AllocaN; // Alloca(ptr, N) operation
+ }
+ else if ((opLabel == Instruction::Load ||
+ opLabel == Instruction::GetElementPtr)
+ && ((MemAccessInst*)_instr)->getFirstOffsetIdx() > 0)
+ {
+ opLabel = opLabel + 100; // load/getElem with index vector
+ }
+ else if (opLabel == Instruction::Cast)
+ {
+ const Type* instrValueType = _instr->getType();
+ switch(instrValueType->getPrimitiveID())
+ {
+ case Type::BoolTyID: opLabel = ToBoolTy; break;
+ case Type::UByteTyID: opLabel = ToUByteTy; break;
+ case Type::SByteTyID: opLabel = ToSByteTy; break;
+ case Type::UShortTyID: opLabel = ToUShortTy; break;
+ case Type::ShortTyID: opLabel = ToShortTy; break;
+ case Type::UIntTyID: opLabel = ToUIntTy; break;
+ case Type::IntTyID: opLabel = ToIntTy; break;
+ case Type::ULongTyID: opLabel = ToULongTy; break;
+ case Type::LongTyID: opLabel = ToLongTy; break;
+ case Type::FloatTyID: opLabel = ToFloatTy; break;
+ case Type::DoubleTyID: opLabel = ToDoubleTy; break;
+ default:
+ if (instrValueType->isArrayType())
+ opLabel = ToArrayTy;
+ else if (instrValueType->isPointerType())
+ opLabel = ToPointerTy;
+ else
+ ; // Just use `Cast' opcode otherwise. It's probably ignored.
+ break;
+ }
+ }
+
+ basicNode.opLabel = opLabel;
+}
+
+void
+InstructionNode::reverseBinaryArgumentOrder()
+{
+ assert(getInstruction()->isBinaryOp());
+
+ // switch arguments for the instruction
+ ((BinaryOperator*) getInstruction())->swapOperands();
+
+ // switch arguments for this tree node itself
+ BasicTreeNode* leftCopy = basicNode.leftChild;
+ basicNode.leftChild = basicNode.rightChild;
+ basicNode.rightChild = leftCopy;
+}
+
+void
+InstructionNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << getInstruction()->getOpcodeName();
+
+ const vector<MachineInstr*>& mvec = getInstruction()->getMachineInstrVec();
+ if (mvec.size() > 0)
+ cout << "\tMachine Instructions: ";
+ for (unsigned int i=0; i < mvec.size(); i++)
+ {
+ mvec[i]->dump(0);
+ if (i < mvec.size() - 1)
+ cout << "; ";
+ }
+
+ cout << endl;
+}
+
+
+VRegListNode::VRegListNode()
+ : InstrTreeNode(NTVRegListNode, NULL)
+{
+ basicNode.opLabel = VRegListOp;
+}
+
+void
+VRegListNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "List" << endl;
+}
+
+
+VRegNode::VRegNode(Value* _val)
+ : InstrTreeNode(NTVRegNode, _val)
+{
+ basicNode.opLabel = VRegNodeOp;
+}
+
+void
+VRegNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "VReg " << getValue() << "\t(type "
+ << (int) getValue()->getValueType() << ")" << endl;
+}
+
+
+ConstantNode::ConstantNode(ConstPoolVal* constVal)
+ : InstrTreeNode(NTConstNode, constVal)
+{
+ basicNode.opLabel = ConstantNodeOp;
+}
+
+void
+ConstantNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "Constant " << getValue() << "\t(type "
+ << (int) getValue()->getValueType() << ")" << endl;
+}
+
+
+LabelNode::LabelNode(BasicBlock* _bblock)
+ : InstrTreeNode(NTLabelNode, _bblock)
+{
+ basicNode.opLabel = LabelNodeOp;
+}
+
+void
+LabelNode::dumpNode(int indent) const
+{
+ for (int i=0; i < indent; i++)
+ cout << " ";
+
+ cout << "Label " << getValue() << endl;
+}
+
+//------------------------------------------------------------------------
+// class InstrForest
+//
+// A forest of instruction trees, usually for a single method.
+//------------------------------------------------------------------------
+
+void
+InstrForest::buildTreesForMethod(Method *method)
+{
+ for (Method::inst_iterator instrIter = method->inst_begin();
+ instrIter != method->inst_end();
+ ++instrIter)
+ {
+ Instruction *instr = *instrIter;
+ if (! instr->isPHINode())
+ (void) this->buildTreeForInstruction(instr);
+ }
+}
+
+
+void
+InstrForest::dump() const
+{
+ for (hash_set<InstructionNode*, ptrHashFunc >::const_iterator
+ treeRootIter = treeRoots.begin();
+ treeRootIter != treeRoots.end();
+ ++treeRootIter)
+ {
+ (*treeRootIter)->dump(/*dumpChildren*/ 1, /*indent*/ 0);
+ }
+}
+
+inline void
+InstrForest::noteTreeNodeForInstr(Instruction* instr,
+ InstructionNode* treeNode)
+{
+ assert(treeNode->getNodeType() == InstrTreeNode::NTInstructionNode);
+ (*this)[instr] = treeNode;
+ treeRoots.insert(treeNode); // mark node as root of a new tree
+}
+
+
+inline void
+InstrForest::setLeftChild(InstrTreeNode* parent, InstrTreeNode* child)
+{
+ parent->basicNode.leftChild = & child->basicNode;
+ child->basicNode.parent = & parent->basicNode;
+ if (child->getNodeType() == InstrTreeNode::NTInstructionNode)
+ treeRoots.erase((InstructionNode*) child); // no longer a tree root
+}
+
+
+inline void
+InstrForest::setRightChild(InstrTreeNode* parent, InstrTreeNode* child)
+{
+ parent->basicNode.rightChild = & child->basicNode;
+ child->basicNode.parent = & parent->basicNode;
+ if (child->getNodeType() == InstrTreeNode::NTInstructionNode)
+ treeRoots.erase((InstructionNode*) child); // no longer a tree root
+}
+
+
+InstructionNode*
+InstrForest::buildTreeForInstruction(Instruction* instr)
+{
+ InstructionNode* treeNode = this->getTreeNodeForInstr(instr);
+ if (treeNode != NULL)
+ {// treeNode has already been constructed for this instruction
+ assert(treeNode->getInstruction() == instr);
+ return treeNode;
+ }
+
+ // Otherwise, create a new tree node for this instruction.
+ //
+ treeNode = new InstructionNode(instr);
+ this->noteTreeNodeForInstr(instr, treeNode);
+
+ // If the instruction has more than 2 instruction operands,
+ // then we will not add any children. This assumes that instructions
+ // like 'call' that have more than 2 instruction operands do not
+ // ever get combined with the instructions that compute the operands.
+ // Note that we only count operands of type instruction and not other
+ // values such as branch labels for a branch or switch instruction.
+ //
+ // To do this efficiently, we'll walk all operands, build treeNodes
+ // for all instruction operands and save them in an array, and then
+ // insert children at the end if there are not more than 2.
+ // As a performance optimization, allocate a child array only
+ // if a fixed array is too small.
+ //
+ int numChildren = 0;
+ const unsigned int MAX_CHILD = 8;
+ static InstrTreeNode* fixedChildArray[MAX_CHILD];
+ InstrTreeNode** childArray =
+ (instr->getNumOperands() > MAX_CHILD)
+ ? new (InstrTreeNode*)[instr->getNumOperands()]
+ : fixedChildArray;
+
+ //
+ // Walk the operands of the instruction
+ //
+ for (Instruction::op_iterator opIter = instr->op_begin();
+ opIter != instr->op_end();
+ ++opIter)
+ {
+ Value* operand = *opIter;
+
+ // Check if the operand is a data value, not an branch label, type,
+ // method or module. If the operand is an address type (i.e., label
+ // or method) that is used in an non-branching operation, e.g., `add'.
+ // that should be considered a data value.
+
+ // Check latter condition here just to simplify the next IF.
+ bool includeAddressOperand =
+ ((operand->getValueType() == Value::BasicBlockVal
+ || operand->getValueType() == Value::MethodVal)
+ && ! instr->isTerminator());
+
+ if (/* (*opIter) != NULL
+ &&*/ includeAddressOperand
+ || operand->getValueType() == Value::InstructionVal
+ || operand->getValueType() == Value::ConstantVal
+ || operand->getValueType() == Value::MethodArgumentVal)
+ {// This operand is a data value
+
+ // An instruction that computes the incoming value is added as a
+ // child of the current instruction if:
+ // the value has only a single use
+ // AND both instructions are in the same basic block
+ // AND the instruction is not a PHI
+ //
+ // (Note that if the value has only a single use (viz., `instr'),
+ // the def of the value can be safely moved just before instr
+ // and therefore it is safe to combine these two instructions.)
+ //
+ // In all other cases, the virtual register holding the value
+ // is used directly, i.e., made a child of the instruction node.
+ //
+ InstrTreeNode* opTreeNode;
+ if (operand->getValueType() == Value::InstructionVal
+ && operand->use_size() == 1
+ && ((Instruction*)operand)->getParent() == instr->getParent()
+ && ! ((Instruction*)operand)->isPHINode())
+ {
+ // Recursively create a treeNode for it.
+ opTreeNode =this->buildTreeForInstruction((Instruction*)operand);
+ }
+ else if (operand->getValueType() == Value::ConstantVal)
+ {
+ // Create a leaf node for a constant
+ opTreeNode = new ConstantNode((ConstPoolVal*) operand);
+ }
+ else
+ {
+ // Create a leaf node for the virtual register
+ opTreeNode = new VRegNode(operand);
+ }
+
+ childArray[numChildren] = opTreeNode;
+ numChildren++;
+ }
+ }
+
+ //--------------------------------------------------------------------
+ // Add any selected operands as children in the tree.
+ // Certain instructions can have more than 2 in some instances (viz.,
+ // a CALL or a memory access -- LOAD, STORE, and GetElemPtr -- to an
+ // array or struct). Make the operands of every such instruction into
+ // a right-leaning binary tree with the operand nodes at the leaves
+ // and VRegList nodes as internal nodes.
+ //--------------------------------------------------------------------
+
+ InstrTreeNode* parent = treeNode; // new VRegListNode();
+ int n;
+
+ if (numChildren > 2)
+ {
+ unsigned instrOpcode = treeNode->getInstruction()->getOpcode();
+ assert(instrOpcode == Instruction::Call ||
+ instrOpcode == Instruction::Load ||
+ instrOpcode == Instruction::Store ||
+ instrOpcode == Instruction::GetElementPtr);
+ }
+
+ // Insert the first child as a direct child
+ if (numChildren >= 1)
+ this->setLeftChild(parent, childArray[0]);
+
+ // Create a list node for children 2 .. N-1, if any
+ for (n = numChildren-1; n >= 2; n--)
+ { // We have more than two children
+ InstrTreeNode* listNode = new VRegListNode();
+ this->setRightChild(parent, listNode);
+ this->setLeftChild(listNode, childArray[numChildren - n]);
+ parent = listNode;
+ }
+
+ // Now insert the last remaining child (if any).
+ if (numChildren >= 2)
+ {
+ assert(n == 1);
+ this->setRightChild(parent, childArray[numChildren - 1]);
+ }
+
+ if (childArray != fixedChildArray)
+ {
+ delete[] childArray;
+ }
+
+ return treeNode;
+}
+
--- /dev/null
+// $Id$ -*-c++-*-
+//***************************************************************************
+// File:
+// InstrSelection.h
+//
+// Purpose:
+//
+// History:
+// 7/02/01 - Vikram Adve - Created
+//***************************************************************************
+
+
+//************************** System Include Files **************************/
+
+#include <assert.h>
+#include <stdio.h>
+#include <iostream.h>
+#include <bool.h>
+#include <string>
+
+//*************************** User Include Files ***************************/
+
+#include "llvm/Method.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/Type.h"
+#include "llvm/iMemory.h"
+#include "llvm/Instruction.h"
+#include "llvm/LLC/CompileContext.h"
+#include "llvm/Codegen/InstrForest.h"
+#include "llvm/Codegen/MachineInstr.h"
+#include "llvm/Codegen/InstrSelection.h"
+
+
+//************************* Forward Declarations ***************************/
+
+static bool SelectInstructionsForTree (BasicTreeNode* treeRoot,
+ int goalnt,
+ CompileContext& ccontext);
+
+
+//******************* Externally Visible Functions *************************/
+
+
+//---------------------------------------------------------------------------
+// Entry point for instruction selection using BURG.
+// Returns true if instruction selection failed, false otherwise.
+//---------------------------------------------------------------------------
+
+bool
+SelectInstructionsForMethod(Method* method,
+ CompileContext& ccontext)
+{
+ bool failed = false;
+
+ InstrForest instrForest;
+ instrForest.buildTreesForMethod(method);
+
+ const hash_set<InstructionNode*, ptrHashFunc>&
+ treeRoots = instrForest.getRootSet();
+
+ //
+ // Invoke BURG instruction selection for each tree
+ //
+ for (hash_set<InstructionNode*, ptrHashFunc >::const_iterator
+ treeRootIter = treeRoots.begin();
+ treeRootIter != treeRoots.end();
+ ++treeRootIter)
+ {
+ BasicTreeNode* basicNode = (*treeRootIter)->getBasicNode();
+
+ // Invoke BURM to label each tree node with a state
+ (void) burm_label(basicNode);
+
+ if (ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT)
+ >= DEBUG_BURG_TREES)
+ {
+ printcover(basicNode, 1, 0);
+ printf("\nCover cost == %d\n\n", treecost(basicNode, 1, 0));
+ printMatches(basicNode);
+ }
+
+ // Then recursively walk the tree to select instructions
+ if (SelectInstructionsForTree(basicNode, /*goalnt*/1, ccontext))
+ {
+ failed = true;
+ break;
+ }
+ }
+
+ if (!failed)
+ {
+ if ( ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT)
+ >= DEBUG_INSTR_TREES)
+ {
+ cout << "\n\n*** Instruction trees for method "
+ << (method->hasName()? method->getName() : "")
+ << endl << endl;
+ instrForest.dump();
+ }
+
+ if (ccontext.getOptions().IntOptionValue(DEBUG_INSTR_SELECT_OPT) > 0)
+ PrintMachineInstructions(method, ccontext);
+ }
+
+ return false;
+}
+
+
+//---------------------------------------------------------------------------
+// Function: FoldGetElemChain
+//
+// Purpose:
+// Fold a chain of GetElementPtr instructions into an equivalent
+// (Pointer, IndexVector) pair. Returns the pointer Value, and
+// stores the resulting IndexVector in argument chainIdxVec.
+//---------------------------------------------------------------------------
+
+Value*
+FoldGetElemChain(const InstructionNode* getElemInstrNode,
+ vector<ConstPoolVal*>& chainIdxVec)
+{
+ MemAccessInst* getElemInst = (MemAccessInst*)
+ getElemInstrNode->getInstruction();
+
+ // Initialize return values from the incoming instruction
+ Value* ptrVal = getElemInst->getPtrOperand();
+ chainIdxVec = getElemInst->getIndexVec(); // copies index vector values
+
+ // Now chase the chain of getElementInstr instructions, if any
+ InstrTreeNode* ptrChild = getElemInstrNode->leftChild();
+ while (ptrChild->getOpLabel() == Instruction::GetElementPtr ||
+ ptrChild->getOpLabel() == GetElemPtrIdx)
+ {
+ // Child is a GetElemPtr instruction
+ getElemInst = (MemAccessInst*)
+ ((InstructionNode*) ptrChild)->getInstruction();
+ const vector<ConstPoolVal*>& idxVec = getElemInst->getIndexVec();
+
+ // Get the pointer value out of ptrChild and *prepend* its index vector
+ ptrVal = getElemInst->getPtrOperand();
+ chainIdxVec.insert(chainIdxVec.begin(), idxVec.begin(), idxVec.end());
+
+ ptrChild = ptrChild->leftChild();
+ }
+
+ return ptrVal;
+}
+
+
+void
+PrintMachineInstructions(Method* method,
+ CompileContext& ccontext)
+{
+ cout << "\n" << method->getReturnType()
+ << " \"" << method->getName() << "\"" << endl;
+
+ for (Method::const_iterator bbIter = method->begin();
+ bbIter != method->end();
+ ++bbIter)
+ {
+ BasicBlock* bb = *bbIter;
+ cout << "\n"
+ << (bb->hasName()? bb->getName() : "Label")
+ << " (" << bb << ")" << ":"
+ << endl;
+
+ for (BasicBlock::const_iterator instrIter = bb->begin();
+ instrIter != bb->end();
+ ++instrIter)
+ {
+ Instruction *instr = *instrIter;
+ const MachineCodeForVMInstr& minstrVec = instr->getMachineInstrVec();
+ for (unsigned i=0, N=minstrVec.size(); i < N; i++)
+ cout << "\t" << *minstrVec[i] << endl;
+ }
+ }
+}
+
+//*********************** Private Functions *****************************/
+
+
+//---------------------------------------------------------------------------
+// Function SelectInstructionsForTree
+//
+// Recursively walk the tree to select instructions.
+// Do this top-down so that child instructions can exploit decisions
+// made at the child instructions.
+//
+// E.g., if br(setle(reg,const)) decides the constant is 0 and uses
+// a branch-on-integer-register instruction, then the setle node
+// can use that information to avoid generating the SUBcc instruction.
+//
+// Note that this cannot be done bottom-up because setle must do this
+// only if it is a child of the branch (otherwise, the result of setle
+// may be used by multiple instructions).
+//---------------------------------------------------------------------------
+
+bool
+SelectInstructionsForTree(BasicTreeNode* treeRoot,
+ int goalnt,
+ CompileContext& ccontext)
+{
+ // Use a static vector to avoid allocating a new one per VM instruction
+ static MachineInstr* minstrVec[MAX_INSTR_PER_VMINSTR];
+
+ // Get the rule that matches this node.
+ //
+ int ruleForNode = burm_rule(treeRoot->state, goalnt);
+
+ if (ruleForNode == 0)
+ {
+ cerr << "Could not match instruction tree for instr selection" << endl;
+ return true;
+ }
+
+ // Get this rule's non-terminals and the corresponding child nodes (if any)
+ //
+ short *nts = burm_nts[ruleForNode];
+
+
+ // First, select instructions for the current node and rule.
+ // (If this is a list node, not an instruction, then skip this step).
+ // This function is specific to the target architecture.
+ //
+ if (treeRoot->opLabel != VRegListOp)
+ {
+ InstructionNode* instrNode = (InstructionNode*) MainTreeNode(treeRoot);
+ assert(instrNode->getNodeType() == InstrTreeNode::NTInstructionNode);
+
+ unsigned N = GetInstructionsByRule(instrNode, ruleForNode, nts, ccontext,
+ minstrVec);
+ assert(N <= MAX_INSTR_PER_VMINSTR);
+ for (unsigned i=0; i < N; i++)
+ {
+ assert(minstrVec[i] != NULL);
+ instrNode->getInstruction()->addMachineInstruction(minstrVec[i]);
+ }
+ }
+
+ // Then, recursively compile the child nodes, if any.
+ //
+ if (nts[0])
+ { // i.e., there is at least one kid
+
+ BasicTreeNode* kids[2];
+ int currentRule = ruleForNode;
+ burm_kids(treeRoot, currentRule, kids);
+
+ // First skip over any chain rules so that we don't visit
+ // the current node again.
+ //
+ while (ThisIsAChainRule(currentRule))
+ {
+ currentRule = burm_rule(treeRoot->state, nts[0]);
+ nts = burm_nts[currentRule];
+ burm_kids(treeRoot, currentRule, kids);
+ }
+
+ // Now we have the first non-chain rule so we have found
+ // the actual child nodes. Recursively compile them.
+ //
+ for (int i = 0; nts[i]; i++)
+ {
+ assert(i < 2);
+ InstrTreeNode::InstrTreeNodeType
+ nodeType = MainTreeNode(kids[i])->getNodeType();
+ if (nodeType == InstrTreeNode::NTVRegListNode ||
+ nodeType == InstrTreeNode::NTInstructionNode)
+ {
+ bool failed= SelectInstructionsForTree(kids[i], nts[i],ccontext);
+ if (failed)
+ return true; // failure
+ }
+ }
+ }
+
+ return false; // success
+}
+
--- /dev/null
+LEVEL = ../../..
+
+DIRS =
+
+LIBRARYNAME = select
+
+## List source files in link order
+Source = \
+ InstrSelection.o \
+ MachineInstr.o \
+ InstrForest.o
+
+include $(LEVEL)/Makefile.common
projects / oota-llvm.git / commitdiff