X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;ds=sidebyside;f=lib%2FCodeGen%2FMachineRegisterInfo.cpp;h=7244d5f03a90a8fd7e6de3d97e53a8ed4a9f3d4f;hb=b34d837397053da8e9bff90dd714e24f2a3b98b3;hp=9649c4c44ce72919dfd69d304fdf913c275d27ca;hpb=90f95f88c6ce09c6744777dc9d140c3c77203b92;p=oota-llvm.git diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp index 9649c4c44ce..7244d5f03a9 100644 --- a/lib/CodeGen/MachineRegisterInfo.cpp +++ b/lib/CodeGen/MachineRegisterInfo.cpp @@ -12,12 +12,15 @@ //===----------------------------------------------------------------------===// #include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/Target/TargetInstrInfo.h" +#include "llvm/Support/CommandLine.h" using namespace llvm; MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI) { VRegInfo.reserve(256); RegAllocHints.reserve(256); - RegClass2VRegMap.resize(TRI.getNumRegClasses()+1); // RC ID starts at 1. + RegClass2VRegMap = new std::vector[TRI.getNumRegClasses()]; UsedPhysRegs.resize(TRI.getNumRegs()); // Create the physreg use/def lists. @@ -27,33 +30,47 @@ MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI) { MachineRegisterInfo::~MachineRegisterInfo() { #ifndef NDEBUG - for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i) - assert(VRegInfo[i].second == 0 && "Vreg use list non-empty still?"); + for (unsigned i = 0, e = getNumVirtRegs(); i != e; ++i) + assert(VRegInfo[TargetRegisterInfo::index2VirtReg(i)].second == 0 && + "Vreg use list non-empty still?"); for (unsigned i = 0, e = UsedPhysRegs.size(); i != e; ++i) assert(!PhysRegUseDefLists[i] && "PhysRegUseDefLists has entries after all instructions are deleted"); #endif delete [] PhysRegUseDefLists; + delete [] RegClass2VRegMap; } /// setRegClass - Set the register class of the specified virtual register. /// void MachineRegisterInfo::setRegClass(unsigned Reg, const TargetRegisterClass *RC) { - unsigned VR = Reg; - Reg -= TargetRegisterInfo::FirstVirtualRegister; - assert(Reg < VRegInfo.size() && "Invalid vreg!"); const TargetRegisterClass *OldRC = VRegInfo[Reg].first; VRegInfo[Reg].first = RC; // Remove from old register class's vregs list. This may be slow but // fortunately this operation is rarely needed. std::vector &VRegs = RegClass2VRegMap[OldRC->getID()]; - std::vector::iterator I=std::find(VRegs.begin(), VRegs.end(), VR); + std::vector::iterator I = + std::find(VRegs.begin(), VRegs.end(), Reg); VRegs.erase(I); // Add to new register class's vregs list. - RegClass2VRegMap[RC->getID()].push_back(VR); + RegClass2VRegMap[RC->getID()].push_back(Reg); +} + +const TargetRegisterClass * +MachineRegisterInfo::constrainRegClass(unsigned Reg, + const TargetRegisterClass *RC) { + const TargetRegisterClass *OldRC = getRegClass(Reg); + if (OldRC == RC) + return RC; + const TargetRegisterClass *NewRC = getCommonSubClass(OldRC, RC); + if (!NewRC) + return 0; + if (NewRC != OldRC) + setRegClass(Reg, NewRC); + return NewRC; } /// createVirtualRegister - Create and return a new virtual register in the @@ -62,17 +79,22 @@ MachineRegisterInfo::setRegClass(unsigned Reg, const TargetRegisterClass *RC) { unsigned MachineRegisterInfo::createVirtualRegister(const TargetRegisterClass *RegClass){ assert(RegClass && "Cannot create register without RegClass!"); + + // New virtual register number. + unsigned Reg = TargetRegisterInfo::index2VirtReg(getNumVirtRegs()); + // Add a reg, but keep track of whether the vector reallocated or not. - void *ArrayBase = VRegInfo.empty() ? 0 : &VRegInfo[0]; - VRegInfo.push_back(std::make_pair(RegClass, (MachineOperand*)0)); - RegAllocHints.push_back(std::make_pair(RA_None, 0)); + const unsigned FirstVirtReg = TargetRegisterInfo::index2VirtReg(0); + void *ArrayBase = getNumVirtRegs() == 0 ? 0 : &VRegInfo[FirstVirtReg]; + VRegInfo.grow(Reg); + VRegInfo[Reg].first = RegClass; + RegAllocHints.grow(Reg); - if (!((&VRegInfo[0] == ArrayBase || VRegInfo.size() == 1))) + if (ArrayBase && &VRegInfo[FirstVirtReg] != ArrayBase) // The vector reallocated, handle this now. HandleVRegListReallocation(); - unsigned VR = getLastVirtReg(); - RegClass2VRegMap[RegClass->getID()].push_back(VR); - return VR; + RegClass2VRegMap[RegClass->getID()].push_back(Reg); + return Reg; } /// HandleVRegListReallocation - We just added a virtual register to the @@ -81,11 +103,12 @@ MachineRegisterInfo::createVirtualRegister(const TargetRegisterClass *RegClass){ void MachineRegisterInfo::HandleVRegListReallocation() { // The back pointers for the vreg lists point into the previous vector. // Update them to point to their correct slots. - for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i) { - MachineOperand *List = VRegInfo[i].second; + for (unsigned i = 0, e = getNumVirtRegs(); i != e; ++i) { + unsigned Reg = TargetRegisterInfo::index2VirtReg(i); + MachineOperand *List = VRegInfo[Reg].second; if (!List) continue; // Update the back-pointer to be accurate once more. - List->Contents.Reg.Prev = &VRegInfo[i].second; + List->Contents.Reg.Prev = &VRegInfo[Reg].second; } } @@ -108,16 +131,107 @@ void MachineRegisterInfo::replaceRegWith(unsigned FromReg, unsigned ToReg) { /// register or null if none is found. This assumes that the code is in SSA /// form, so there should only be one definition. MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const { - assert(Reg-TargetRegisterInfo::FirstVirtualRegister < VRegInfo.size() && - "Invalid vreg!"); - for (reg_iterator I = reg_begin(Reg), E = reg_end(); I != E; ++I) { - // Since we are in SSA form, we can stop at the first definition. - if (I.getOperand().isDef()) - return &*I; - } + // Since we are in SSA form, we can use the first definition. + if (!def_empty(Reg)) + return &*def_begin(Reg); + return 0; +} + +bool MachineRegisterInfo::hasOneUse(unsigned RegNo) const { + use_iterator UI = use_begin(RegNo); + if (UI == use_end()) + return false; + return ++UI == use_end(); +} + +bool MachineRegisterInfo::hasOneNonDBGUse(unsigned RegNo) const { + use_nodbg_iterator UI = use_nodbg_begin(RegNo); + if (UI == use_nodbg_end()) + return false; + return ++UI == use_nodbg_end(); +} + +/// clearKillFlags - Iterate over all the uses of the given register and +/// clear the kill flag from the MachineOperand. This function is used by +/// optimization passes which extend register lifetimes and need only +/// preserve conservative kill flag information. +void MachineRegisterInfo::clearKillFlags(unsigned Reg) const { + for (use_iterator UI = use_begin(Reg), UE = use_end(); UI != UE; ++UI) + UI.getOperand().setIsKill(false); +} + +bool MachineRegisterInfo::isLiveIn(unsigned Reg) const { + for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) + if (I->first == Reg || I->second == Reg) + return true; + return false; +} + +bool MachineRegisterInfo::isLiveOut(unsigned Reg) const { + for (liveout_iterator I = liveout_begin(), E = liveout_end(); I != E; ++I) + if (*I == Reg) + return true; + return false; +} + +/// getLiveInPhysReg - If VReg is a live-in virtual register, return the +/// corresponding live-in physical register. +unsigned MachineRegisterInfo::getLiveInPhysReg(unsigned VReg) const { + for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) + if (I->second == VReg) + return I->first; return 0; } +/// getLiveInVirtReg - If PReg is a live-in physical register, return the +/// corresponding live-in physical register. +unsigned MachineRegisterInfo::getLiveInVirtReg(unsigned PReg) const { + for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) + if (I->first == PReg) + return I->second; + return 0; +} + +/// EmitLiveInCopies - Emit copies to initialize livein virtual registers +/// into the given entry block. +void +MachineRegisterInfo::EmitLiveInCopies(MachineBasicBlock *EntryMBB, + const TargetRegisterInfo &TRI, + const TargetInstrInfo &TII) { + // Emit the copies into the top of the block. + for (unsigned i = 0, e = LiveIns.size(); i != e; ++i) + if (LiveIns[i].second) { + if (use_empty(LiveIns[i].second)) { + // The livein has no uses. Drop it. + // + // It would be preferable to have isel avoid creating live-in + // records for unused arguments in the first place, but it's + // complicated by the debug info code for arguments. + LiveIns.erase(LiveIns.begin() + i); + --i; --e; + } else { + // Emit a copy. + BuildMI(*EntryMBB, EntryMBB->begin(), DebugLoc(), + TII.get(TargetOpcode::COPY), LiveIns[i].second) + .addReg(LiveIns[i].first); + + // Add the register to the entry block live-in set. + EntryMBB->addLiveIn(LiveIns[i].first); + } + } else { + // Add the register to the entry block live-in set. + EntryMBB->addLiveIn(LiveIns[i].first); + } +} + +void MachineRegisterInfo::closePhysRegsUsed(const TargetRegisterInfo &TRI) { + for (int i = UsedPhysRegs.find_first(); i >= 0; + i = UsedPhysRegs.find_next(i)) + for (const unsigned *SS = TRI.getSubRegisters(i); + unsigned SubReg = *SS; ++SS) + if (SubReg > unsigned(i)) + UsedPhysRegs.set(SubReg); +} #ifndef NDEBUG void MachineRegisterInfo::dumpUses(unsigned Reg) const {