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	results. This works around a problem affecting targets which rely on MVT::Flag to handle physical register defs. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85638 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			702 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			702 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //==--- InstrEmitter.cpp - Emit MachineInstrs for the SelectionDAG class ---==//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This implements the Emit routines for the SelectionDAG class, which creates
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| // MachineInstrs based on the decisions of the SelectionDAG instruction
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| // selection.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #define DEBUG_TYPE "instr-emitter"
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| #include "InstrEmitter.h"
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| #include "llvm/CodeGen/MachineConstantPool.h"
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| #include "llvm/CodeGen/MachineFunction.h"
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| #include "llvm/CodeGen/MachineInstrBuilder.h"
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| #include "llvm/CodeGen/MachineRegisterInfo.h"
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| #include "llvm/Target/TargetData.h"
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| #include "llvm/Target/TargetMachine.h"
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| #include "llvm/Target/TargetInstrInfo.h"
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| #include "llvm/Target/TargetLowering.h"
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| #include "llvm/ADT/Statistic.h"
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| #include "llvm/Support/CommandLine.h"
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| #include "llvm/Support/Debug.h"
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| #include "llvm/Support/ErrorHandling.h"
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| #include "llvm/Support/MathExtras.h"
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| using namespace llvm;
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| 
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| /// CountResults - The results of target nodes have register or immediate
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| /// operands first, then an optional chain, and optional flag operands (which do
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| /// not go into the resulting MachineInstr).
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| unsigned InstrEmitter::CountResults(SDNode *Node) {
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|   unsigned N = Node->getNumValues();
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|   while (N && Node->getValueType(N - 1) == MVT::Flag)
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|     --N;
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|   if (N && Node->getValueType(N - 1) == MVT::Other)
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|     --N;    // Skip over chain result.
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|   return N;
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| }
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| 
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| /// CountOperands - The inputs to target nodes have any actual inputs first,
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| /// followed by an optional chain operand, then an optional flag operand.
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| /// Compute the number of actual operands that will go into the resulting
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| /// MachineInstr.
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| unsigned InstrEmitter::CountOperands(SDNode *Node) {
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|   unsigned N = Node->getNumOperands();
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|   while (N && Node->getOperand(N - 1).getValueType() == MVT::Flag)
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|     --N;
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|   if (N && Node->getOperand(N - 1).getValueType() == MVT::Other)
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|     --N; // Ignore chain if it exists.
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|   return N;
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| }
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| 
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| /// EmitCopyFromReg - Generate machine code for an CopyFromReg node or an
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| /// implicit physical register output.
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| void InstrEmitter::
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| EmitCopyFromReg(SDNode *Node, unsigned ResNo, bool IsClone, bool IsCloned,
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|                 unsigned SrcReg, DenseMap<SDValue, unsigned> &VRBaseMap) {
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|   unsigned VRBase = 0;
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|   if (TargetRegisterInfo::isVirtualRegister(SrcReg)) {
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|     // Just use the input register directly!
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|     SDValue Op(Node, ResNo);
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|     if (IsClone)
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|       VRBaseMap.erase(Op);
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|     bool isNew = VRBaseMap.insert(std::make_pair(Op, SrcReg)).second;
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|     isNew = isNew; // Silence compiler warning.
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|     assert(isNew && "Node emitted out of order - early");
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|     return;
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|   }
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| 
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|   // If the node is only used by a CopyToReg and the dest reg is a vreg, use
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|   // the CopyToReg'd destination register instead of creating a new vreg.
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|   bool MatchReg = true;
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|   const TargetRegisterClass *UseRC = NULL;
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|   if (!IsClone && !IsCloned)
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|     for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
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|          UI != E; ++UI) {
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|       SDNode *User = *UI;
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|       bool Match = true;
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|       if (User->getOpcode() == ISD::CopyToReg && 
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|           User->getOperand(2).getNode() == Node &&
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|           User->getOperand(2).getResNo() == ResNo) {
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|         unsigned DestReg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
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|         if (TargetRegisterInfo::isVirtualRegister(DestReg)) {
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|           VRBase = DestReg;
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|           Match = false;
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|         } else if (DestReg != SrcReg)
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|           Match = false;
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|       } else {
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|         for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) {
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|           SDValue Op = User->getOperand(i);
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|           if (Op.getNode() != Node || Op.getResNo() != ResNo)
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|             continue;
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|           EVT VT = Node->getValueType(Op.getResNo());
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|           if (VT == MVT::Other || VT == MVT::Flag)
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|             continue;
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|           Match = false;
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|           if (User->isMachineOpcode()) {
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|             const TargetInstrDesc &II = TII->get(User->getMachineOpcode());
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|             const TargetRegisterClass *RC = 0;
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|             if (i+II.getNumDefs() < II.getNumOperands())
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|               RC = II.OpInfo[i+II.getNumDefs()].getRegClass(TRI);
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|             if (!UseRC)
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|               UseRC = RC;
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|             else if (RC) {
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|               const TargetRegisterClass *ComRC = getCommonSubClass(UseRC, RC);
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|               // If multiple uses expect disjoint register classes, we emit
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|               // copies in AddRegisterOperand.
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|               if (ComRC)
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|                 UseRC = ComRC;
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|             }
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|           }
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|         }
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|       }
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|       MatchReg &= Match;
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|       if (VRBase)
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|         break;
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|     }
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| 
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|   EVT VT = Node->getValueType(ResNo);
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|   const TargetRegisterClass *SrcRC = 0, *DstRC = 0;
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|   SrcRC = TRI->getPhysicalRegisterRegClass(SrcReg, VT);
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|   
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|   // Figure out the register class to create for the destreg.
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|   if (VRBase) {
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|     DstRC = MRI->getRegClass(VRBase);
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|   } else if (UseRC) {
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|     assert(UseRC->hasType(VT) && "Incompatible phys register def and uses!");
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|     DstRC = UseRC;
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|   } else {
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|     DstRC = TLI->getRegClassFor(VT);
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|   }
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|     
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|   // If all uses are reading from the src physical register and copying the
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|   // register is either impossible or very expensive, then don't create a copy.
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|   if (MatchReg && SrcRC->getCopyCost() < 0) {
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|     VRBase = SrcReg;
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|   } else {
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|     // Create the reg, emit the copy.
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|     VRBase = MRI->createVirtualRegister(DstRC);
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|     bool Emitted = TII->copyRegToReg(*MBB, InsertPos, VRBase, SrcReg,
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|                                      DstRC, SrcRC);
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| 
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|     assert(Emitted && "Unable to issue a copy instruction!\n");
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|     (void) Emitted;
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|   }
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| 
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|   SDValue Op(Node, ResNo);
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|   if (IsClone)
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|     VRBaseMap.erase(Op);
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|   bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
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|   isNew = isNew; // Silence compiler warning.
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|   assert(isNew && "Node emitted out of order - early");
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| }
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| 
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| /// getDstOfCopyToRegUse - If the only use of the specified result number of
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| /// node is a CopyToReg, return its destination register. Return 0 otherwise.
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| unsigned InstrEmitter::getDstOfOnlyCopyToRegUse(SDNode *Node,
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|                                                 unsigned ResNo) const {
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|   if (!Node->hasOneUse())
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|     return 0;
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| 
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|   SDNode *User = *Node->use_begin();
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|   if (User->getOpcode() == ISD::CopyToReg && 
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|       User->getOperand(2).getNode() == Node &&
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|       User->getOperand(2).getResNo() == ResNo) {
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|     unsigned Reg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
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|     if (TargetRegisterInfo::isVirtualRegister(Reg))
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|       return Reg;
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|   }
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|   return 0;
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| }
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| 
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| void InstrEmitter::CreateVirtualRegisters(SDNode *Node, MachineInstr *MI,
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|                                        const TargetInstrDesc &II,
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|                                        bool IsClone, bool IsCloned,
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|                                        DenseMap<SDValue, unsigned> &VRBaseMap) {
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|   assert(Node->getMachineOpcode() != TargetInstrInfo::IMPLICIT_DEF &&
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|          "IMPLICIT_DEF should have been handled as a special case elsewhere!");
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| 
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|   for (unsigned i = 0; i < II.getNumDefs(); ++i) {
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|     // If the specific node value is only used by a CopyToReg and the dest reg
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|     // is a vreg in the same register class, use the CopyToReg'd destination
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|     // register instead of creating a new vreg.
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|     unsigned VRBase = 0;
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|     const TargetRegisterClass *RC = II.OpInfo[i].getRegClass(TRI);
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|     if (II.OpInfo[i].isOptionalDef()) {
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|       // Optional def must be a physical register.
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|       unsigned NumResults = CountResults(Node);
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|       VRBase = cast<RegisterSDNode>(Node->getOperand(i-NumResults))->getReg();
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|       assert(TargetRegisterInfo::isPhysicalRegister(VRBase));
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|       MI->addOperand(MachineOperand::CreateReg(VRBase, true));
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|     }
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| 
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|     if (!VRBase && !IsClone && !IsCloned)
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|       for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
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|            UI != E; ++UI) {
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|         SDNode *User = *UI;
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|         if (User->getOpcode() == ISD::CopyToReg && 
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|             User->getOperand(2).getNode() == Node &&
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|             User->getOperand(2).getResNo() == i) {
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|           unsigned Reg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
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|           if (TargetRegisterInfo::isVirtualRegister(Reg)) {
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|             const TargetRegisterClass *RegRC = MRI->getRegClass(Reg);
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|             if (RegRC == RC) {
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|               VRBase = Reg;
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|               MI->addOperand(MachineOperand::CreateReg(Reg, true));
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|               break;
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|             }
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|           }
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|         }
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|       }
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| 
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|     // Create the result registers for this node and add the result regs to
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|     // the machine instruction.
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|     if (VRBase == 0) {
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|       assert(RC && "Isn't a register operand!");
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|       VRBase = MRI->createVirtualRegister(RC);
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|       MI->addOperand(MachineOperand::CreateReg(VRBase, true));
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|     }
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| 
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|     SDValue Op(Node, i);
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|     if (IsClone)
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|       VRBaseMap.erase(Op);
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|     bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
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|     isNew = isNew; // Silence compiler warning.
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|     assert(isNew && "Node emitted out of order - early");
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|   }
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| }
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| 
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| /// getVR - Return the virtual register corresponding to the specified result
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| /// of the specified node.
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| unsigned InstrEmitter::getVR(SDValue Op,
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|                              DenseMap<SDValue, unsigned> &VRBaseMap) {
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|   if (Op.isMachineOpcode() &&
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|       Op.getMachineOpcode() == TargetInstrInfo::IMPLICIT_DEF) {
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|     // Add an IMPLICIT_DEF instruction before every use.
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|     unsigned VReg = getDstOfOnlyCopyToRegUse(Op.getNode(), Op.getResNo());
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|     // IMPLICIT_DEF can produce any type of result so its TargetInstrDesc
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|     // does not include operand register class info.
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|     if (!VReg) {
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|       const TargetRegisterClass *RC = TLI->getRegClassFor(Op.getValueType());
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|       VReg = MRI->createVirtualRegister(RC);
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|     }
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|     BuildMI(MBB, Op.getDebugLoc(),
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|             TII->get(TargetInstrInfo::IMPLICIT_DEF), VReg);
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|     return VReg;
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|   }
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| 
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|   DenseMap<SDValue, unsigned>::iterator I = VRBaseMap.find(Op);
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|   assert(I != VRBaseMap.end() && "Node emitted out of order - late");
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|   return I->second;
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| }
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| 
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| 
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| /// AddRegisterOperand - Add the specified register as an operand to the
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| /// specified machine instr. Insert register copies if the register is
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| /// not in the required register class.
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| void
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| InstrEmitter::AddRegisterOperand(MachineInstr *MI, SDValue Op,
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|                                  unsigned IIOpNum,
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|                                  const TargetInstrDesc *II,
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|                                  DenseMap<SDValue, unsigned> &VRBaseMap) {
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|   assert(Op.getValueType() != MVT::Other &&
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|          Op.getValueType() != MVT::Flag &&
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|          "Chain and flag operands should occur at end of operand list!");
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|   // Get/emit the operand.
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|   unsigned VReg = getVR(Op, VRBaseMap);
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|   assert(TargetRegisterInfo::isVirtualRegister(VReg) && "Not a vreg?");
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| 
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|   const TargetInstrDesc &TID = MI->getDesc();
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|   bool isOptDef = IIOpNum < TID.getNumOperands() &&
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|     TID.OpInfo[IIOpNum].isOptionalDef();
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| 
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|   // If the instruction requires a register in a different class, create
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|   // a new virtual register and copy the value into it.
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|   if (II) {
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|     const TargetRegisterClass *SrcRC = MRI->getRegClass(VReg);
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|     const TargetRegisterClass *DstRC = 0;
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|     if (IIOpNum < II->getNumOperands())
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|       DstRC = II->OpInfo[IIOpNum].getRegClass(TRI);
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|     assert((DstRC || (TID.isVariadic() && IIOpNum >= TID.getNumOperands())) &&
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|            "Don't have operand info for this instruction!");
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|     if (DstRC && SrcRC != DstRC && !SrcRC->hasSuperClass(DstRC)) {
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|       unsigned NewVReg = MRI->createVirtualRegister(DstRC);
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|       bool Emitted = TII->copyRegToReg(*MBB, InsertPos, NewVReg, VReg,
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|                                        DstRC, SrcRC);
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|       assert(Emitted && "Unable to issue a copy instruction!\n");
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|       (void) Emitted;
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|       VReg = NewVReg;
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|     }
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|   }
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| 
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|   MI->addOperand(MachineOperand::CreateReg(VReg, isOptDef));
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| }
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| 
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| /// AddOperand - Add the specified operand to the specified machine instr.  II
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| /// specifies the instruction information for the node, and IIOpNum is the
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| /// operand number (in the II) that we are adding. IIOpNum and II are used for 
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| /// assertions only.
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| void InstrEmitter::AddOperand(MachineInstr *MI, SDValue Op,
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|                               unsigned IIOpNum,
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|                               const TargetInstrDesc *II,
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|                               DenseMap<SDValue, unsigned> &VRBaseMap) {
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|   if (Op.isMachineOpcode()) {
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|     AddRegisterOperand(MI, Op, IIOpNum, II, VRBaseMap);
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|   } else if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateImm(C->getSExtValue()));
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|   } else if (ConstantFPSDNode *F = dyn_cast<ConstantFPSDNode>(Op)) {
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|     const ConstantFP *CFP = F->getConstantFPValue();
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|     MI->addOperand(MachineOperand::CreateFPImm(CFP));
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|   } else if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateReg(R->getReg(), false));
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|   } else if (GlobalAddressSDNode *TGA = dyn_cast<GlobalAddressSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateGA(TGA->getGlobal(), TGA->getOffset(),
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|                                             TGA->getTargetFlags()));
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|   } else if (BasicBlockSDNode *BBNode = dyn_cast<BasicBlockSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateMBB(BBNode->getBasicBlock()));
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|   } else if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateFI(FI->getIndex()));
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|   } else if (JumpTableSDNode *JT = dyn_cast<JumpTableSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateJTI(JT->getIndex(),
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|                                              JT->getTargetFlags()));
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|   } else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(Op)) {
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|     int Offset = CP->getOffset();
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|     unsigned Align = CP->getAlignment();
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|     const Type *Type = CP->getType();
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|     // MachineConstantPool wants an explicit alignment.
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|     if (Align == 0) {
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|       Align = TM->getTargetData()->getPrefTypeAlignment(Type);
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|       if (Align == 0) {
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|         // Alignment of vector types.  FIXME!
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|         Align = TM->getTargetData()->getTypeAllocSize(Type);
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|       }
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|     }
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|     
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|     unsigned Idx;
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|     MachineConstantPool *MCP = MF->getConstantPool();
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|     if (CP->isMachineConstantPoolEntry())
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|       Idx = MCP->getConstantPoolIndex(CP->getMachineCPVal(), Align);
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|     else
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|       Idx = MCP->getConstantPoolIndex(CP->getConstVal(), Align);
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|     MI->addOperand(MachineOperand::CreateCPI(Idx, Offset,
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|                                              CP->getTargetFlags()));
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|   } else if (ExternalSymbolSDNode *ES = dyn_cast<ExternalSymbolSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateES(ES->getSymbol(),
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|                                             ES->getTargetFlags()));
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|   } else if (BlockAddressSDNode *BA = dyn_cast<BlockAddressSDNode>(Op)) {
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|     MI->addOperand(MachineOperand::CreateBA(BA->getBlockAddress()));
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|   } else {
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|     assert(Op.getValueType() != MVT::Other &&
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|            Op.getValueType() != MVT::Flag &&
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|            "Chain and flag operands should occur at end of operand list!");
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|     AddRegisterOperand(MI, Op, IIOpNum, II, VRBaseMap);
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|   }
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| }
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| 
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| /// getSuperRegisterRegClass - Returns the register class of a superreg A whose
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| /// "SubIdx"'th sub-register class is the specified register class and whose
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| /// type matches the specified type.
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| static const TargetRegisterClass*
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| getSuperRegisterRegClass(const TargetRegisterClass *TRC,
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|                          unsigned SubIdx, EVT VT) {
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|   // Pick the register class of the superegister for this type
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|   for (TargetRegisterInfo::regclass_iterator I = TRC->superregclasses_begin(),
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|          E = TRC->superregclasses_end(); I != E; ++I)
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|     if ((*I)->hasType(VT) && (*I)->getSubRegisterRegClass(SubIdx) == TRC)
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|       return *I;
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|   assert(false && "Couldn't find the register class");
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|   return 0;
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| }
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| 
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| /// EmitSubregNode - Generate machine code for subreg nodes.
 | |
| ///
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| void InstrEmitter::EmitSubregNode(SDNode *Node, 
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|                                   DenseMap<SDValue, unsigned> &VRBaseMap){
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|   unsigned VRBase = 0;
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|   unsigned Opc = Node->getMachineOpcode();
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|   
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|   // If the node is only used by a CopyToReg and the dest reg is a vreg, use
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|   // the CopyToReg'd destination register instead of creating a new vreg.
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|   for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
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|        UI != E; ++UI) {
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|     SDNode *User = *UI;
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|     if (User->getOpcode() == ISD::CopyToReg && 
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|         User->getOperand(2).getNode() == Node) {
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|       unsigned DestReg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
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|       if (TargetRegisterInfo::isVirtualRegister(DestReg)) {
 | |
|         VRBase = DestReg;
 | |
|         break;
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   
 | |
|   if (Opc == TargetInstrInfo::EXTRACT_SUBREG) {
 | |
|     unsigned SubIdx = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
 | |
| 
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|     // Create the extract_subreg machine instruction.
 | |
|     MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(),
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|                                TII->get(TargetInstrInfo::EXTRACT_SUBREG));
 | |
| 
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|     // Figure out the register class to create for the destreg.
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|     unsigned VReg = getVR(Node->getOperand(0), VRBaseMap);
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|     const TargetRegisterClass *TRC = MRI->getRegClass(VReg);
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|     const TargetRegisterClass *SRC = TRC->getSubRegisterRegClass(SubIdx);
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|     assert(SRC && "Invalid subregister index in EXTRACT_SUBREG");
 | |
| 
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|     // Figure out the register class to create for the destreg.
 | |
|     // Note that if we're going to directly use an existing register,
 | |
|     // it must be precisely the required class, and not a subclass
 | |
|     // thereof.
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|     if (VRBase == 0 || SRC != MRI->getRegClass(VRBase)) {
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|       // Create the reg
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|       assert(SRC && "Couldn't find source register class");
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|       VRBase = MRI->createVirtualRegister(SRC);
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|     }
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| 
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|     // Add def, source, and subreg index
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|     MI->addOperand(MachineOperand::CreateReg(VRBase, true));
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|     AddOperand(MI, Node->getOperand(0), 0, 0, VRBaseMap);
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|     MI->addOperand(MachineOperand::CreateImm(SubIdx));
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|     MBB->insert(InsertPos, MI);
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|   } else if (Opc == TargetInstrInfo::INSERT_SUBREG ||
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|              Opc == TargetInstrInfo::SUBREG_TO_REG) {
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|     SDValue N0 = Node->getOperand(0);
 | |
|     SDValue N1 = Node->getOperand(1);
 | |
|     SDValue N2 = Node->getOperand(2);
 | |
|     unsigned SubReg = getVR(N1, VRBaseMap);
 | |
|     unsigned SubIdx = cast<ConstantSDNode>(N2)->getZExtValue();
 | |
|     const TargetRegisterClass *TRC = MRI->getRegClass(SubReg);
 | |
|     const TargetRegisterClass *SRC =
 | |
|       getSuperRegisterRegClass(TRC, SubIdx,
 | |
|                                Node->getValueType(0));
 | |
| 
 | |
|     // Figure out the register class to create for the destreg.
 | |
|     // Note that if we're going to directly use an existing register,
 | |
|     // it must be precisely the required class, and not a subclass
 | |
|     // thereof.
 | |
|     if (VRBase == 0 || SRC != MRI->getRegClass(VRBase)) {
 | |
|       // Create the reg
 | |
|       assert(SRC && "Couldn't find source register class");
 | |
|       VRBase = MRI->createVirtualRegister(SRC);
 | |
|     }
 | |
| 
 | |
|     // Create the insert_subreg or subreg_to_reg machine instruction.
 | |
|     MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(), TII->get(Opc));
 | |
|     MI->addOperand(MachineOperand::CreateReg(VRBase, true));
 | |
|     
 | |
|     // If creating a subreg_to_reg, then the first input operand
 | |
|     // is an implicit value immediate, otherwise it's a register
 | |
|     if (Opc == TargetInstrInfo::SUBREG_TO_REG) {
 | |
|       const ConstantSDNode *SD = cast<ConstantSDNode>(N0);
 | |
|       MI->addOperand(MachineOperand::CreateImm(SD->getZExtValue()));
 | |
|     } else
 | |
|       AddOperand(MI, N0, 0, 0, VRBaseMap);
 | |
|     // Add the subregster being inserted
 | |
|     AddOperand(MI, N1, 0, 0, VRBaseMap);
 | |
|     MI->addOperand(MachineOperand::CreateImm(SubIdx));
 | |
|     MBB->insert(InsertPos, MI);
 | |
|   } else
 | |
|     llvm_unreachable("Node is not insert_subreg, extract_subreg, or subreg_to_reg");
 | |
|      
 | |
|   SDValue Op(Node, 0);
 | |
|   bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
 | |
|   isNew = isNew; // Silence compiler warning.
 | |
|   assert(isNew && "Node emitted out of order - early");
 | |
| }
 | |
| 
 | |
| /// EmitCopyToRegClassNode - Generate machine code for COPY_TO_REGCLASS nodes.
 | |
| /// COPY_TO_REGCLASS is just a normal copy, except that the destination
 | |
| /// register is constrained to be in a particular register class.
 | |
| ///
 | |
| void
 | |
| InstrEmitter::EmitCopyToRegClassNode(SDNode *Node,
 | |
|                                      DenseMap<SDValue, unsigned> &VRBaseMap) {
 | |
|   unsigned VReg = getVR(Node->getOperand(0), VRBaseMap);
 | |
|   const TargetRegisterClass *SrcRC = MRI->getRegClass(VReg);
 | |
| 
 | |
|   unsigned DstRCIdx = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
 | |
|   const TargetRegisterClass *DstRC = TRI->getRegClass(DstRCIdx);
 | |
| 
 | |
|   // Create the new VReg in the destination class and emit a copy.
 | |
|   unsigned NewVReg = MRI->createVirtualRegister(DstRC);
 | |
|   bool Emitted = TII->copyRegToReg(*MBB, InsertPos, NewVReg, VReg,
 | |
|                                    DstRC, SrcRC);
 | |
|   assert(Emitted &&
 | |
|          "Unable to issue a copy instruction for a COPY_TO_REGCLASS node!\n");
 | |
|   (void) Emitted;
 | |
| 
 | |
|   SDValue Op(Node, 0);
 | |
|   bool isNew = VRBaseMap.insert(std::make_pair(Op, NewVReg)).second;
 | |
|   isNew = isNew; // Silence compiler warning.
 | |
|   assert(isNew && "Node emitted out of order - early");
 | |
| }
 | |
| 
 | |
| /// EmitNode - Generate machine code for an node and needed dependencies.
 | |
| ///
 | |
| void InstrEmitter::EmitNode(SDNode *Node, bool IsClone, bool IsCloned,
 | |
|                             DenseMap<SDValue, unsigned> &VRBaseMap,
 | |
|                          DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) {
 | |
|   // If machine instruction
 | |
|   if (Node->isMachineOpcode()) {
 | |
|     unsigned Opc = Node->getMachineOpcode();
 | |
|     
 | |
|     // Handle subreg insert/extract specially
 | |
|     if (Opc == TargetInstrInfo::EXTRACT_SUBREG || 
 | |
|         Opc == TargetInstrInfo::INSERT_SUBREG ||
 | |
|         Opc == TargetInstrInfo::SUBREG_TO_REG) {
 | |
|       EmitSubregNode(Node, VRBaseMap);
 | |
|       return;
 | |
|     }
 | |
| 
 | |
|     // Handle COPY_TO_REGCLASS specially.
 | |
|     if (Opc == TargetInstrInfo::COPY_TO_REGCLASS) {
 | |
|       EmitCopyToRegClassNode(Node, VRBaseMap);
 | |
|       return;
 | |
|     }
 | |
| 
 | |
|     if (Opc == TargetInstrInfo::IMPLICIT_DEF)
 | |
|       // We want a unique VR for each IMPLICIT_DEF use.
 | |
|       return;
 | |
|     
 | |
|     const TargetInstrDesc &II = TII->get(Opc);
 | |
|     unsigned NumResults = CountResults(Node);
 | |
|     unsigned NodeOperands = CountOperands(Node);
 | |
|     bool HasPhysRegOuts = (NumResults > II.getNumDefs()) &&
 | |
|                           II.getImplicitDefs() != 0;
 | |
| #ifndef NDEBUG
 | |
|     unsigned NumMIOperands = NodeOperands + NumResults;
 | |
|     assert((II.getNumOperands() == NumMIOperands ||
 | |
|             HasPhysRegOuts || II.isVariadic()) &&
 | |
|            "#operands for dag node doesn't match .td file!"); 
 | |
| #endif
 | |
| 
 | |
|     // Create the new machine instruction.
 | |
|     MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(), II);
 | |
|     
 | |
|     // Add result register values for things that are defined by this
 | |
|     // instruction.
 | |
|     if (NumResults)
 | |
|       CreateVirtualRegisters(Node, MI, II, IsClone, IsCloned, VRBaseMap);
 | |
|     
 | |
|     // Emit all of the actual operands of this instruction, adding them to the
 | |
|     // instruction as appropriate.
 | |
|     bool HasOptPRefs = II.getNumDefs() > NumResults;
 | |
|     assert((!HasOptPRefs || !HasPhysRegOuts) &&
 | |
|            "Unable to cope with optional defs and phys regs defs!");
 | |
|     unsigned NumSkip = HasOptPRefs ? II.getNumDefs() - NumResults : 0;
 | |
|     for (unsigned i = NumSkip; i != NodeOperands; ++i)
 | |
|       AddOperand(MI, Node->getOperand(i), i-NumSkip+II.getNumDefs(), &II,
 | |
|                  VRBaseMap);
 | |
| 
 | |
|     // Transfer all of the memory reference descriptions of this instruction.
 | |
|     MI->setMemRefs(cast<MachineSDNode>(Node)->memoperands_begin(),
 | |
|                    cast<MachineSDNode>(Node)->memoperands_end());
 | |
| 
 | |
|     if (II.usesCustomInsertionHook()) {
 | |
|       // Insert this instruction into the basic block using a target
 | |
|       // specific inserter which may returns a new basic block.
 | |
|       MBB = TLI->EmitInstrWithCustomInserter(MI, MBB, EM);
 | |
|       InsertPos = MBB->end();
 | |
|     } else {
 | |
|       MBB->insert(InsertPos, MI);
 | |
|     }
 | |
| 
 | |
|     // Additional results must be an physical register def.
 | |
|     if (HasPhysRegOuts) {
 | |
|       for (unsigned i = II.getNumDefs(); i < NumResults; ++i) {
 | |
|         unsigned Reg = II.getImplicitDefs()[i - II.getNumDefs()];
 | |
|         if (Node->hasAnyUseOfValue(i))
 | |
|           EmitCopyFromReg(Node, i, IsClone, IsCloned, Reg, VRBaseMap);
 | |
|         // If there are no uses, mark the register as dead now, so that
 | |
|         // MachineLICM/Sink can see that it's dead. Don't do this if the
 | |
|         // node has a Flag value, for the benefit of targets still using
 | |
|         // Flag for values in physregs.
 | |
|         else if (Node->getValueType(Node->getNumValues()-1) != MVT::Flag)
 | |
|           MI->addRegisterDead(Reg, TRI);
 | |
|       }
 | |
|     }
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   switch (Node->getOpcode()) {
 | |
|   default:
 | |
| #ifndef NDEBUG
 | |
|     Node->dump();
 | |
| #endif
 | |
|     llvm_unreachable("This target-independent node should have been selected!");
 | |
|     break;
 | |
|   case ISD::EntryToken:
 | |
|     llvm_unreachable("EntryToken should have been excluded from the schedule!");
 | |
|     break;
 | |
|   case ISD::MERGE_VALUES:
 | |
|   case ISD::TokenFactor: // fall thru
 | |
|     break;
 | |
|   case ISD::CopyToReg: {
 | |
|     unsigned SrcReg;
 | |
|     SDValue SrcVal = Node->getOperand(2);
 | |
|     if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(SrcVal))
 | |
|       SrcReg = R->getReg();
 | |
|     else
 | |
|       SrcReg = getVR(SrcVal, VRBaseMap);
 | |
|       
 | |
|     unsigned DestReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
 | |
|     if (SrcReg == DestReg) // Coalesced away the copy? Ignore.
 | |
|       break;
 | |
|       
 | |
|     const TargetRegisterClass *SrcTRC = 0, *DstTRC = 0;
 | |
|     // Get the register classes of the src/dst.
 | |
|     if (TargetRegisterInfo::isVirtualRegister(SrcReg))
 | |
|       SrcTRC = MRI->getRegClass(SrcReg);
 | |
|     else
 | |
|       SrcTRC = TRI->getPhysicalRegisterRegClass(SrcReg,SrcVal.getValueType());
 | |
| 
 | |
|     if (TargetRegisterInfo::isVirtualRegister(DestReg))
 | |
|       DstTRC = MRI->getRegClass(DestReg);
 | |
|     else
 | |
|       DstTRC = TRI->getPhysicalRegisterRegClass(DestReg,
 | |
|                                             Node->getOperand(1).getValueType());
 | |
| 
 | |
|     bool Emitted = TII->copyRegToReg(*MBB, InsertPos, DestReg, SrcReg,
 | |
|                                      DstTRC, SrcTRC);
 | |
|     assert(Emitted && "Unable to issue a copy instruction!\n");
 | |
|     (void) Emitted;
 | |
|     break;
 | |
|   }
 | |
|   case ISD::CopyFromReg: {
 | |
|     unsigned SrcReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
 | |
|     EmitCopyFromReg(Node, 0, IsClone, IsCloned, SrcReg, VRBaseMap);
 | |
|     break;
 | |
|   }
 | |
|   case ISD::INLINEASM: {
 | |
|     unsigned NumOps = Node->getNumOperands();
 | |
|     if (Node->getOperand(NumOps-1).getValueType() == MVT::Flag)
 | |
|       --NumOps;  // Ignore the flag operand.
 | |
|       
 | |
|     // Create the inline asm machine instruction.
 | |
|     MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(),
 | |
|                                TII->get(TargetInstrInfo::INLINEASM));
 | |
| 
 | |
|     // Add the asm string as an external symbol operand.
 | |
|     const char *AsmStr =
 | |
|       cast<ExternalSymbolSDNode>(Node->getOperand(1))->getSymbol();
 | |
|     MI->addOperand(MachineOperand::CreateES(AsmStr));
 | |
|       
 | |
|     // Add all of the operand registers to the instruction.
 | |
|     for (unsigned i = 2; i != NumOps;) {
 | |
|       unsigned Flags =
 | |
|         cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
 | |
|       unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
 | |
|         
 | |
|       MI->addOperand(MachineOperand::CreateImm(Flags));
 | |
|       ++i;  // Skip the ID value.
 | |
|         
 | |
|       switch (Flags & 7) {
 | |
|       default: llvm_unreachable("Bad flags!");
 | |
|       case 2:   // Def of register.
 | |
|         for (; NumVals; --NumVals, ++i) {
 | |
|           unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
 | |
|           MI->addOperand(MachineOperand::CreateReg(Reg, true));
 | |
|         }
 | |
|         break;
 | |
|       case 6:   // Def of earlyclobber register.
 | |
|         for (; NumVals; --NumVals, ++i) {
 | |
|           unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
 | |
|           MI->addOperand(MachineOperand::CreateReg(Reg, true, false, false, 
 | |
|                                                    false, false, true));
 | |
|         }
 | |
|         break;
 | |
|       case 1:  // Use of register.
 | |
|       case 3:  // Immediate.
 | |
|       case 4:  // Addressing mode.
 | |
|         // The addressing mode has been selected, just add all of the
 | |
|         // operands to the machine instruction.
 | |
|         for (; NumVals; --NumVals, ++i)
 | |
|           AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
 | |
|         break;
 | |
|       }
 | |
|     }
 | |
|     MBB->insert(InsertPos, MI);
 | |
|     break;
 | |
|   }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /// InstrEmitter - Construct an InstrEmitter and set it to start inserting
 | |
| /// at the given position in the given block.
 | |
| InstrEmitter::InstrEmitter(MachineBasicBlock *mbb,
 | |
|                            MachineBasicBlock::iterator insertpos)
 | |
|   : MF(mbb->getParent()),
 | |
|     MRI(&MF->getRegInfo()),
 | |
|     TM(&MF->getTarget()),
 | |
|     TII(TM->getInstrInfo()),
 | |
|     TRI(TM->getRegisterInfo()),
 | |
|     TLI(TM->getTargetLowering()),
 | |
|     MBB(mbb), InsertPos(insertpos) {
 | |
| }
 |