- for (unsigned idx = 0, e = MI->getNumOperands(); idx != e; ++idx) {
- // Consider replacing all frame index operands that reference
- // an object allocated in the local block.
- if (MI->getOperand(idx).isFI()) {
- int FrameIdx = MI->getOperand(idx).getIndex();
-
- assert(MFI->isObjectPreAllocated(FrameIdx) &&
- "Only pre-allocated locals expected!");
-
- DEBUG(dbgs() << "Considering: " << *MI);
- if (TRI->needsFrameBaseReg(MI, LocalOffsets[FrameIdx])) {
- unsigned BaseReg = 0;
- int64_t Offset = 0;
- int64_t FrameSizeAdjust =
- StackGrowsDown ? MFI->getLocalFrameSize() : 0;
-
- DEBUG(dbgs() << " Replacing FI in: " << *MI);
-
- // If we have a suitable base register available, use it; otherwise
- // create a new one. Note that any offset encoded in the
- // instruction itself will be taken into account by the target,
- // so we don't have to adjust for it here when reusing a base
- // register.
- std::pair<unsigned, int64_t> RegOffset;
- if (lookupCandidateBaseReg(BaseRegisters, RegOffset,
- FrameSizeAdjust,
- LocalOffsets[FrameIdx],
- MI, TRI)) {
- DEBUG(dbgs() << " Reusing base register " <<
- RegOffset.first << "\n");
- // We found a register to reuse.
- BaseReg = RegOffset.first;
- Offset = FrameSizeAdjust + LocalOffsets[FrameIdx] -
- RegOffset.second;
- } else {
- // No previously defined register was in range, so create a
- // new one.
- int64_t InstrOffset = TRI->getFrameIndexInstrOffset(MI, idx);
- const TargetRegisterClass *RC = TRI->getPointerRegClass();
- BaseReg = Fn.getRegInfo().createVirtualRegister(RC);
-
- DEBUG(dbgs() << " Materializing base register " << BaseReg <<
- " at frame local offset " <<
- LocalOffsets[FrameIdx] + InstrOffset << "\n");
-
- // Tell the target to insert the instruction to initialize
- // the base register.
- // MachineBasicBlock::iterator InsertionPt = Entry->begin();
- TRI->materializeFrameBaseRegister(Entry, BaseReg, FrameIdx,
- InstrOffset);
-
- // The base register already includes any offset specified
- // by the instruction, so account for that so it doesn't get
- // applied twice.
- Offset = -InstrOffset;
-
- int64_t BaseOffset = FrameSizeAdjust + LocalOffsets[FrameIdx] +
- InstrOffset;
- BaseRegisters.push_back(
- std::pair<unsigned, int64_t>(BaseReg, BaseOffset));
- ++NumBaseRegisters;
- UsedBaseReg = true;
- }
- assert(BaseReg != 0 && "Unable to allocate virtual base register!");
-
- // Modify the instruction to use the new base register rather
- // than the frame index operand.
- TRI->resolveFrameIndex(I, BaseReg, Offset);
- DEBUG(dbgs() << "Resolved: " << *MI);
-
- ++NumReplacements;
- }
+ int64_t LocalOffset = FR.getLocalOffset();
+ int FrameIdx = FR.getFrameIndex();
+ assert(MFI->isObjectPreAllocated(FrameIdx) &&
+ "Only pre-allocated locals expected!");
+
+ DEBUG(dbgs() << "Considering: " << *MI);
+
+ unsigned idx = 0;
+ for (unsigned f = MI->getNumOperands(); idx != f; ++idx) {
+ if (!MI->getOperand(idx).isFI())
+ continue;
+
+ if (FrameIdx == I->getOperand(idx).getIndex())
+ break;
+ }
+
+ assert(idx < MI->getNumOperands() && "Cannot find FI operand");
+
+ int64_t Offset = 0;
+ int64_t FrameSizeAdjust = StackGrowsDown ? MFI->getLocalFrameSize() : 0;
+
+ DEBUG(dbgs() << " Replacing FI in: " << *MI);
+
+ // If we have a suitable base register available, use it; otherwise
+ // create a new one. Note that any offset encoded in the
+ // instruction itself will be taken into account by the target,
+ // so we don't have to adjust for it here when reusing a base
+ // register.
+ if (UsedBaseReg && lookupCandidateBaseReg(BaseReg, BaseOffset,
+ FrameSizeAdjust, LocalOffset, MI,
+ TRI)) {
+ DEBUG(dbgs() << " Reusing base register " << BaseReg << "\n");
+ // We found a register to reuse.
+ Offset = FrameSizeAdjust + LocalOffset - BaseOffset;
+ } else {
+ // No previously defined register was in range, so create a // new one.
+
+ int64_t InstrOffset = TRI->getFrameIndexInstrOffset(MI, idx);
+
+ int64_t PrevBaseOffset = BaseOffset;
+ BaseOffset = FrameSizeAdjust + LocalOffset + InstrOffset;
+
+ // We'd like to avoid creating single-use virtual base registers.
+ // Because the FrameRefs are in sorted order, and we've already
+ // processed all FrameRefs before this one, just check whether or not
+ // the next FrameRef will be able to reuse this new register. If not,
+ // then don't bother creating it.
+ if (ref + 1 >= e ||
+ !lookupCandidateBaseReg(
+ BaseReg, BaseOffset, FrameSizeAdjust,
+ FrameReferenceInsns[ref + 1].getLocalOffset(),
+ FrameReferenceInsns[ref + 1].getMachineInstr(), TRI)) {
+ BaseOffset = PrevBaseOffset;
+ continue;