void PeepholePPC64();
void PeepholdCROps();
+
+ bool AllUsersSelectZero(SDNode *N);
+ void SwapAllSelectUsers(SDNode *N);
};
}
PeepholdCROps();
}
+// Check if all users of this node will become isel where the second operand
+// is the constant zero. If this is so, and if we can negate the condition,
+// then we can flip the true and false operands. This will allow the zero to
+// be folded with the isel so that we don't need to materialize a register
+// containing zero.
+bool PPCDAGToDAGISel::AllUsersSelectZero(SDNode *N) {
+ // If we're not using isel, then this does not matter.
+ if (!PPCSubTarget.hasISEL())
+ return false;
+
+ for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
+ UI != UE; ++UI) {
+ SDNode *User = *UI;
+ if (!User->isMachineOpcode())
+ return false;
+ if (User->getMachineOpcode() != PPC::SELECT_I4 &&
+ User->getMachineOpcode() != PPC::SELECT_I8)
+ return false;
+
+ SDNode *Op2 = User->getOperand(2).getNode();
+ if (!Op2->isMachineOpcode())
+ return false;
+
+ if (Op2->getMachineOpcode() != PPC::LI &&
+ Op2->getMachineOpcode() != PPC::LI8)
+ return false;
+
+ ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op2->getOperand(0));
+ if (!C)
+ return false;
+
+ if (!C->isNullValue())
+ return false;
+ }
+
+ return true;
+}
+
+void PPCDAGToDAGISel::SwapAllSelectUsers(SDNode *N) {
+ SmallVector<SDNode *, 4> ToReplace;
+ for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
+ UI != UE; ++UI) {
+ SDNode *User = *UI;
+ assert((User->getMachineOpcode() == PPC::SELECT_I4 ||
+ User->getMachineOpcode() == PPC::SELECT_I8) &&
+ "Must have all select users");
+ ToReplace.push_back(User);
+ }
+
+ for (SmallVector<SDNode *, 4>::iterator UI = ToReplace.begin(),
+ UE = ToReplace.end(); UI != UE; ++UI) {
+ SDNode *User = *UI;
+ SDNode *ResNode =
+ CurDAG->getMachineNode(User->getMachineOpcode(), SDLoc(User),
+ User->getValueType(0), User->getOperand(0),
+ User->getOperand(2),
+ User->getOperand(1));
+
+ DEBUG(dbgs() << "CR Peephole replacing:\nOld: ");
+ DEBUG(User->dump(CurDAG));
+ DEBUG(dbgs() << "\nNew: ");
+ DEBUG(ResNode->dump(CurDAG));
+ DEBUG(dbgs() << "\n");
+
+ ReplaceUses(User, ResNode);
+ }
+}
+
void PPCDAGToDAGISel::PeepholdCROps() {
bool IsModified;
do {
break;
}
+ bool SelectSwap = false;
switch (Opcode) {
default: break;
case PPC::CRAND:
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRNAND, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CRNAND:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(1).
getOperand(0),
MachineNode->getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRAND, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CROR:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRNOR, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CRXOR:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CREQV, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CRNOR:
if (Op1Set || Op2Set)
MVT::i1, MachineNode->getOperand(1).
getOperand(0),
MachineNode->getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CROR, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CREQV:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRXOR, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(0),
+ MachineNode->getOperand(1)),
+ SelectSwap = true;
break;
case PPC::CRANDC:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRORC, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(1),
+ MachineNode->getOperand(0)),
+ SelectSwap = true;
break;
case PPC::CRORC:
if (MachineNode->getOperand(0) == MachineNode->getOperand(1))
MVT::i1, MachineNode->getOperand(0),
MachineNode->getOperand(1).
getOperand(0));
+ else if (AllUsersSelectZero(MachineNode))
+ ResNode = CurDAG->getMachineNode(PPC::CRANDC, SDLoc(MachineNode),
+ MVT::i1, MachineNode->getOperand(1),
+ MachineNode->getOperand(0)),
+ SelectSwap = true;
break;
case PPC::SELECT_I4:
case PPC::SELECT_I8:
break;
}
+ // If we're inverting this node because it is used only by selects that
+ // we'd like to swap, then swap the selects before the node replacement.
+ if (SelectSwap)
+ SwapAllSelectUsers(MachineNode);
+
if (ResNode != MachineNode) {
DEBUG(dbgs() << "CR Peephole replacing:\nOld: ");
DEBUG(MachineNode->dump(CurDAG));