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//===- TargetRegisterInfo.cpp - Target Register Information Implementation ===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file implements the TargetRegisterInfo interface.
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//===----------------------------------------------------------------------===//
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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#include "llvm/Target/TargetFrameInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/ADT/BitVector.h"
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TargetRegisterInfo::TargetRegisterInfo(const TargetRegisterDesc *D, unsigned NR,
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regclass_iterator RCB, regclass_iterator RCE,
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const unsigned* subregs, const unsigned subregsize,
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const unsigned* superregs, const unsigned superregsize,
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const unsigned* aliases, const unsigned aliasessize)
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: SubregHash(subregs), SubregHashSize(subregsize),
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SuperregHash(superregs), SuperregHashSize(superregsize),
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AliasesHash(aliases), AliasesHashSize(aliasessize),
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Desc(D), NumRegs(NR), RegClassBegin(RCB), RegClassEnd(RCE) {
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assert(NumRegs < FirstVirtualRegister &&
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"Target has too many physical registers!");
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CallFrameSetupOpcode = CFSO;
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CallFrameDestroyOpcode = CFDO;
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TargetRegisterInfo::~TargetRegisterInfo() {}
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/// getPhysicalRegisterRegClass - Returns the Register Class of a physical
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/// register of the given type. If type is EVT::Other, then just return any
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/// register class the register belongs to.
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const TargetRegisterClass *
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TargetRegisterInfo::getPhysicalRegisterRegClass(unsigned reg, EVT VT) const {
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assert(isPhysicalRegister(reg) && "reg must be a physical register");
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// Pick the most super register class of the right type that contains
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const TargetRegisterClass* BestRC = 0;
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for (regclass_iterator I = regclass_begin(), E = regclass_end(); I != E; ++I){
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const TargetRegisterClass* RC = *I;
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if ((VT == MVT::Other || RC->hasType(VT)) && RC->contains(reg) &&
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(!BestRC || BestRC->hasSuperClass(RC)))
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assert(BestRC && "Couldn't find the register class");
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/// getAllocatableSetForRC - Toggle the bits that represent allocatable
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/// registers for the specific register class.
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static void getAllocatableSetForRC(const MachineFunction &MF,
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const TargetRegisterClass *RC, BitVector &R){
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for (TargetRegisterClass::iterator I = RC->allocation_order_begin(MF),
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E = RC->allocation_order_end(MF); I != E; ++I)
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BitVector TargetRegisterInfo::getAllocatableSet(const MachineFunction &MF,
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const TargetRegisterClass *RC) const {
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BitVector Allocatable(NumRegs);
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getAllocatableSetForRC(MF, RC, Allocatable);
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for (TargetRegisterInfo::regclass_iterator I = regclass_begin(),
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E = regclass_end(); I != E; ++I)
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getAllocatableSetForRC(MF, *I, Allocatable);
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/// getFrameIndexOffset - Returns the displacement from the frame register to
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/// the stack frame of the specified index. This is the default implementation
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/// which is overridden for some targets.
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int TargetRegisterInfo::getFrameIndexOffset(const MachineFunction &MF,
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const TargetFrameInfo &TFI = *MF.getTarget().getFrameInfo();
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const MachineFrameInfo *MFI = MF.getFrameInfo();
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return MFI->getObjectOffset(FI) + MFI->getStackSize() -
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TFI.getOffsetOfLocalArea() + MFI->getOffsetAdjustment();
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/// getInitialFrameState - Returns a list of machine moves that are assumed
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/// on entry to a function.
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TargetRegisterInfo::getInitialFrameState(std::vector<MachineMove> &Moves) const{
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// Default is to do nothing.
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const TargetRegisterClass *
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llvm::getCommonSubClass(const TargetRegisterClass *A,
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const TargetRegisterClass *B) {
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// First take care of the trivial cases
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// If B is a subclass of A, it will be handled in the loop below
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if (B->hasSubClass(A))
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const TargetRegisterClass *Best = 0;
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for (TargetRegisterClass::sc_iterator I = A->subclasses_begin();
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const TargetRegisterClass *X = *I; ++I) {
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return B; // B is a subclass of A
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// X must be a common subclass of A and B
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if (!B->hasSubClass(X))
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// A superclass is definitely better.
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if (!Best || Best->hasSuperClass(X)) {
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// A subclass is definitely worse
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if (Best->hasSubClass(X))
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// Best and *I have no super/sub class relation - pick the larger class, or
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// the smaller spill size.
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int nb = std::distance(Best->begin(), Best->end());
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int ni = std::distance(X->begin(), X->end());
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if (ni>nb || (ni==nb && X->getSize() < Best->getSize()))