//===-- llvm/CodeGen/SSARegMap.h --------------------------------*- C++ -*-===//
-//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
// Map register numbers to register classes that are correctly sized (typed) to
// hold the information. Assists register allocation. Contained by
// MachineFunction, should be deleted by register allocator when it is no
// longer needed.
-//
+//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_SSAREGMAP_H
#define LLVM_CODEGEN_SSAREGMAP_H
#include "llvm/Target/MRegisterInfo.h"
+#include "llvm/ADT/DenseMap.h"
+
+namespace llvm {
class TargetRegisterClass;
class SSARegMap {
- std::vector<const TargetRegisterClass*> RegClassMap;
-
- unsigned rescale(unsigned Reg) {
- return Reg - MRegisterInfo::FirstVirtualRegister;
- }
+ DenseMap<const TargetRegisterClass*, VirtReg2IndexFunctor> RegClassMap;
+ unsigned NextRegNum;
public:
- SSARegMap() {}
+ SSARegMap() : NextRegNum(MRegisterInfo::FirstVirtualRegister) { }
const TargetRegisterClass* getRegClass(unsigned Reg) {
- unsigned actualReg = rescale(Reg);
- assert(actualReg < RegClassMap.size() && "Register out of bounds");
- return RegClassMap[actualReg];
+ return RegClassMap[Reg];
}
- void addRegMap(unsigned Reg, const TargetRegisterClass* RegClass) {
- assert(rescale(Reg) == RegClassMap.size() &&
- "Register mapping not added in sequential order!");
- RegClassMap.push_back(RegClass);
+ /// createVirtualRegister - Create and return a new virtual register in the
+ /// function with the specified register class.
+ ///
+ unsigned createVirtualRegister(const TargetRegisterClass *RegClass) {
+ RegClassMap.grow(NextRegNum);
+ RegClassMap[NextRegNum] = RegClass;
+ return NextRegNum++;
+ }
+
+ unsigned getLastVirtReg() const {
+ return NextRegNum - 1;
}
};
+} // End llvm namespace
+
#endif