llvm-6502/lib/Target/TargetRegisterInfo.cpp
Owen Anderson 1360b7d8f8 Cache subregister relationships in a set in TargetRegisterInfo to allow faster lookups.
This speeds up LiveVariables from 0.6279s to 0.6165s on kimwitu++.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52818 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-27 06:56:04 +00:00

124 lines
4.4 KiB
C++

//===- TargetRegisterInfo.cpp - Target Register Information Implementation ===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the TargetRegisterInfo interface.
//
//===----------------------------------------------------------------------===//
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/ADT/BitVector.h"
using namespace llvm;
TargetRegisterInfo::TargetRegisterInfo(const TargetRegisterDesc *D, unsigned NR,
regclass_iterator RCB, regclass_iterator RCE,
int CFSO, int CFDO)
: Desc(D), NumRegs(NR), RegClassBegin(RCB), RegClassEnd(RCE) {
assert(NumRegs < FirstVirtualRegister &&
"Target has too many physical registers!");
CallFrameSetupOpcode = CFSO;
CallFrameDestroyOpcode = CFDO;
for (unsigned i = 0; i < NumRegs; ++i) {
const TargetRegisterDesc* CurrReg = Desc + i;
// Initialize the Subregs set, which stores pairs (a, b) where
// b is a subreg of a.
if (CurrReg->SubRegs)
for (const unsigned* CurrSR = CurrReg->SubRegs; *CurrSR; ++CurrSR)
Subregs.insert(std::make_pair(i, *CurrSR));
}
}
TargetRegisterInfo::~TargetRegisterInfo() {}
namespace {
// Sort according to super- / sub- class relations.
// i.e. super- register class < sub- register class.
struct RCCompare {
bool operator()(const TargetRegisterClass* const &LHS,
const TargetRegisterClass* const &RHS) {
return RHS->hasSuperClass(LHS);
}
};
}
/// getPhysicalRegisterRegClass - Returns the Register Class of a physical
/// register of the given type. If type is MVT::Other, then just return any
/// register class the register belongs to.
const TargetRegisterClass *
TargetRegisterInfo::getPhysicalRegisterRegClass(unsigned reg, MVT VT) const {
assert(isPhysicalRegister(reg) && "reg must be a physical register");
// Pick the register class of the right type that contains this physreg.
SmallVector<const TargetRegisterClass*, 4> RCs;
for (regclass_iterator I = regclass_begin(), E = regclass_end(); I != E; ++I){
if ((VT == MVT::Other || (*I)->hasType(VT)) && (*I)->contains(reg))
RCs.push_back(*I);
}
if (RCs.size() == 1)
return RCs[0];
if (RCs.size()) {
// Multiple compatible register classes. Get the super- class.
std::stable_sort(RCs.begin(), RCs.end(), RCCompare());
return RCs[0];
}
assert(false && "Couldn't find the register class");
return 0;
}
/// getAllocatableSetForRC - Toggle the bits that represent allocatable
/// registers for the specific register class.
static void getAllocatableSetForRC(MachineFunction &MF,
const TargetRegisterClass *RC, BitVector &R){
for (TargetRegisterClass::iterator I = RC->allocation_order_begin(MF),
E = RC->allocation_order_end(MF); I != E; ++I)
R.set(*I);
}
BitVector TargetRegisterInfo::getAllocatableSet(MachineFunction &MF,
const TargetRegisterClass *RC) const {
BitVector Allocatable(NumRegs);
if (RC) {
getAllocatableSetForRC(MF, RC, Allocatable);
return Allocatable;
}
for (TargetRegisterInfo::regclass_iterator I = regclass_begin(),
E = regclass_end(); I != E; ++I)
getAllocatableSetForRC(MF, *I, Allocatable);
return Allocatable;
}
/// getFrameIndexOffset - Returns the displacement from the frame register to
/// the stack frame of the specified index. This is the default implementation
/// which is likely incorrect for the target.
int TargetRegisterInfo::getFrameIndexOffset(MachineFunction &MF, int FI) const {
const TargetFrameInfo &TFI = *MF.getTarget().getFrameInfo();
MachineFrameInfo *MFI = MF.getFrameInfo();
return MFI->getObjectOffset(FI) + MFI->getStackSize() -
TFI.getOffsetOfLocalArea() + MFI->getOffsetAdjustment();
}
/// getInitialFrameState - Returns a list of machine moves that are assumed
/// on entry to a function.
void
TargetRegisterInfo::getInitialFrameState(std::vector<MachineMove> &Moves) const {
// Default is to do nothing.
}