//===----------------------------------------------------------------------===//
#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);
- RegClass2VRegMap.resize(TRI.getNumRegClasses()+1); // RC ID starts at 1.
+ RegAllocHints.reserve(256);
+ RegClass2VRegMap = new std::vector<unsigned>[TRI.getNumRegClasses()];
UsedPhysRegs.resize(TRI.getNumRegs());
// Create the physreg use/def lists.
"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<unsigned> &VRegs = RegClass2VRegMap[OldRC->getID()];
+ std::vector<unsigned>::iterator I = std::find(VRegs.begin(), VRegs.end(), VR);
+ VRegs.erase(I);
+
+ // Add to new register class's vregs list.
+ RegClass2VRegMap[RC->getID()].push_back(VR);
+}
+
+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
// 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(0, 0));
if (!((&VRegInfo[0] == ArrayBase || VRegInfo.size() == 1)))
// The vector reallocated, handle this now.
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 {