#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetMachine.h"
using namespace llvm;
-MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI) {
+MachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI)
+ : TRI(&TRI), IsSSA(true) {
VRegInfo.reserve(256);
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) {
- 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(), Reg);
- VRegs.erase(I);
-
- // Add to new register class's vregs list.
- RegClass2VRegMap[RC->getID()].push_back(Reg);
}
const TargetRegisterClass *
MachineRegisterInfo::constrainRegClass(unsigned Reg,
- const TargetRegisterClass *RC) {
+ const TargetRegisterClass *RC,
+ unsigned MinNumRegs) {
const TargetRegisterClass *OldRC = getRegClass(Reg);
if (OldRC == RC)
return RC;
- const TargetRegisterClass *NewRC = getCommonSubClass(OldRC, RC);
- if (!NewRC)
+ const TargetRegisterClass *NewRC = TRI->getCommonSubClass(OldRC, RC);
+ if (!NewRC || NewRC == OldRC)
+ return NewRC;
+ if (NewRC->getNumRegs() < MinNumRegs)
return 0;
- if (NewRC != OldRC)
- setRegClass(Reg, NewRC);
+ setRegClass(Reg, NewRC);
return NewRC;
}
+bool
+MachineRegisterInfo::recomputeRegClass(unsigned Reg, const TargetMachine &TM) {
+ const TargetInstrInfo *TII = TM.getInstrInfo();
+ const TargetRegisterClass *OldRC = getRegClass(Reg);
+ const TargetRegisterClass *NewRC = TRI->getLargestLegalSuperClass(OldRC);
+
+ // Stop early if there is no room to grow.
+ if (NewRC == OldRC)
+ return false;
+
+ // Accumulate constraints from all uses.
+ for (reg_nodbg_iterator I = reg_nodbg_begin(Reg), E = reg_nodbg_end(); I != E;
+ ++I) {
+ // TRI doesn't have accurate enough information to model this yet.
+ if (I.getOperand().getSubReg())
+ return false;
+ const TargetRegisterClass *OpRC =
+ I->getRegClassConstraint(I.getOperandNo(), TII, TRI);
+ if (OpRC)
+ NewRC = TRI->getCommonSubClass(NewRC, OpRC);
+ if (!NewRC || NewRC == OldRC)
+ return false;
+ }
+ setRegClass(Reg, NewRC);
+ return true;
+}
+
/// createVirtualRegister - Create and return a new virtual register in the
/// function with the specified register class.
///
if (ArrayBase && &VRegInfo[FirstVirtReg] != ArrayBase)
// The vector reallocated, handle this now.
HandleVRegListReallocation();
- RegClass2VRegMap[RegClass->getID()].push_back(Reg);
return Reg;
}