HexagonSplitConst32AndConst64.cpp revision 263508
1//=== HexagonSplitConst32AndConst64.cpp - split CONST32/Const64 into HI/LO ===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// When the compiler is invoked with no small data, for instance, with the -G0 11// command line option, then all CONST32_* opcodes should be broken down into 12// appropriate LO and HI instructions. This splitting is done by this pass. 13// The only reason this is not done in the DAG lowering itself is that there 14// is no simple way of getting the register allocator to allot the same hard 15// register to the result of LO and HI instructions. This pass is always 16// scheduled after register allocation. 17// 18//===----------------------------------------------------------------------===// 19 20#define DEBUG_TYPE "xfer" 21 22#include "HexagonTargetMachine.h" 23#include "HexagonSubtarget.h" 24#include "HexagonMachineFunctionInfo.h" 25#include "llvm/ADT/Statistic.h" 26#include "llvm/CodeGen/LatencyPriorityQueue.h" 27#include "llvm/CodeGen/MachineDominators.h" 28#include "llvm/CodeGen/MachineFunctionPass.h" 29#include "llvm/CodeGen/MachineInstrBuilder.h" 30#include "llvm/CodeGen/MachineLoopInfo.h" 31#include "llvm/CodeGen/MachineRegisterInfo.h" 32#include "llvm/CodeGen/Passes.h" 33#include "llvm/CodeGen/ScheduleDAGInstrs.h" 34#include "llvm/CodeGen/ScheduleHazardRecognizer.h" 35#include "llvm/CodeGen/SchedulerRegistry.h" 36#include "llvm/Target/TargetMachine.h" 37#include "llvm/Target/TargetInstrInfo.h" 38#include "llvm/Target/TargetRegisterInfo.h" 39#include "llvm/Support/Compiler.h" 40#include "llvm/Support/Debug.h" 41#include "llvm/Support/CommandLine.h" 42#include "llvm/Support/MathExtras.h" 43#include <map> 44 45using namespace llvm; 46 47namespace { 48 49class HexagonSplitConst32AndConst64 : public MachineFunctionPass { 50 const HexagonTargetMachine& QTM; 51 const HexagonSubtarget &QST; 52 53 public: 54 static char ID; 55 HexagonSplitConst32AndConst64(const HexagonTargetMachine& TM) 56 : MachineFunctionPass(ID), QTM(TM), QST(*TM.getSubtargetImpl()) {} 57 58 const char *getPassName() const { 59 return "Hexagon Split Const32s and Const64s"; 60 } 61 bool runOnMachineFunction(MachineFunction &Fn); 62}; 63 64 65char HexagonSplitConst32AndConst64::ID = 0; 66 67 68bool HexagonSplitConst32AndConst64::runOnMachineFunction(MachineFunction &Fn) { 69 70 const TargetInstrInfo *TII = QTM.getInstrInfo(); 71 72 // Loop over all of the basic blocks 73 for (MachineFunction::iterator MBBb = Fn.begin(), MBBe = Fn.end(); 74 MBBb != MBBe; ++MBBb) { 75 MachineBasicBlock* MBB = MBBb; 76 // Traverse the basic block 77 MachineBasicBlock::iterator MII = MBB->begin(); 78 MachineBasicBlock::iterator MIE = MBB->end (); 79 while (MII != MIE) { 80 MachineInstr *MI = MII; 81 int Opc = MI->getOpcode(); 82 if (Opc == Hexagon::CONST32_set) { 83 int DestReg = MI->getOperand(0).getReg(); 84 MachineOperand &Symbol = MI->getOperand (1); 85 86 BuildMI (*MBB, MII, MI->getDebugLoc(), 87 TII->get(Hexagon::LO), DestReg).addOperand(Symbol); 88 BuildMI (*MBB, MII, MI->getDebugLoc(), 89 TII->get(Hexagon::HI), DestReg).addOperand(Symbol); 90 // MBB->erase returns the iterator to the next instruction, which is the 91 // one we want to process next 92 MII = MBB->erase (MI); 93 continue; 94 } 95 else if (Opc == Hexagon::CONST32_set_jt) { 96 int DestReg = MI->getOperand(0).getReg(); 97 MachineOperand &Symbol = MI->getOperand (1); 98 99 BuildMI (*MBB, MII, MI->getDebugLoc(), 100 TII->get(Hexagon::LO_jt), DestReg).addOperand(Symbol); 101 BuildMI (*MBB, MII, MI->getDebugLoc(), 102 TII->get(Hexagon::HI_jt), DestReg).addOperand(Symbol); 103 // MBB->erase returns the iterator to the next instruction, which is the 104 // one we want to process next 105 MII = MBB->erase (MI); 106 continue; 107 } 108 else if (Opc == Hexagon::CONST32_Label) { 109 int DestReg = MI->getOperand(0).getReg(); 110 MachineOperand &Symbol = MI->getOperand (1); 111 112 BuildMI (*MBB, MII, MI->getDebugLoc(), 113 TII->get(Hexagon::LO_label), DestReg).addOperand(Symbol); 114 BuildMI (*MBB, MII, MI->getDebugLoc(), 115 TII->get(Hexagon::HI_label), DestReg).addOperand(Symbol); 116 // MBB->erase returns the iterator to the next instruction, which is the 117 // one we want to process next 118 MII = MBB->erase (MI); 119 continue; 120 } 121 else if (Opc == Hexagon::CONST32_Int_Real) { 122 int DestReg = MI->getOperand(0).getReg(); 123 int64_t ImmValue = MI->getOperand(1).getImm (); 124 125 BuildMI (*MBB, MII, MI->getDebugLoc(), 126 TII->get(Hexagon::LOi), DestReg).addImm(ImmValue); 127 BuildMI (*MBB, MII, MI->getDebugLoc(), 128 TII->get(Hexagon::HIi), DestReg).addImm(ImmValue); 129 MII = MBB->erase (MI); 130 continue; 131 } 132 else if (Opc == Hexagon::CONST64_Int_Real) { 133 int DestReg = MI->getOperand(0).getReg(); 134 int64_t ImmValue = MI->getOperand(1).getImm (); 135 unsigned DestLo = 136 QTM.getRegisterInfo()->getSubReg (DestReg, Hexagon::subreg_loreg); 137 unsigned DestHi = 138 QTM.getRegisterInfo()->getSubReg (DestReg, Hexagon::subreg_hireg); 139 140 int32_t LowWord = (ImmValue & 0xFFFFFFFF); 141 int32_t HighWord = (ImmValue >> 32) & 0xFFFFFFFF; 142 143 // Lower Registers Lower Half 144 BuildMI (*MBB, MII, MI->getDebugLoc(), 145 TII->get(Hexagon::LOi), DestLo).addImm(LowWord); 146 // Lower Registers Higher Half 147 BuildMI (*MBB, MII, MI->getDebugLoc(), 148 TII->get(Hexagon::HIi), DestLo).addImm(LowWord); 149 // Higher Registers Lower Half 150 BuildMI (*MBB, MII, MI->getDebugLoc(), 151 TII->get(Hexagon::LOi), DestHi).addImm(HighWord); 152 // Higher Registers Higher Half. 153 BuildMI (*MBB, MII, MI->getDebugLoc(), 154 TII->get(Hexagon::HIi), DestHi).addImm(HighWord); 155 MII = MBB->erase (MI); 156 continue; 157 } 158 ++MII; 159 } 160 } 161 162 return true; 163} 164 165} 166 167//===----------------------------------------------------------------------===// 168// Public Constructor Functions 169//===----------------------------------------------------------------------===// 170 171FunctionPass * 172llvm::createHexagonSplitConst32AndConst64(const HexagonTargetMachine &TM) { 173 return new HexagonSplitConst32AndConst64(TM); 174} 175