Add a new MVT::untyped. This will be used in future work for modelling ISA features like register pairs and lists with "interesting" constraints (such as ARM NEON contiguous register lists or even-odd paired registers). We need to be able to generate these instructions (often from intrinsics), but don't want to have to assign a legal type to them. Instead, we'll use an "untyped" edge to bypass the type-checking and simply ensure that the register classes match.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133106 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
index 15ce11c..f09b381 100644
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
@@ -276,6 +276,33 @@
};
} // end anonymous namespace
+/// GetCostForDef - Looks up the register class and cost for a given definition.
+/// Typically this just means looking up the representative register class,
+/// but for untyped values (MVT::untyped) it means inspecting the node's
+/// opcode to determine what register class is being generated.
+static void GetCostForDef(const ScheduleDAGSDNodes::RegDefIter &RegDefPos,
+ const TargetLowering *TLI,
+ const TargetInstrInfo *TII,
+ const TargetRegisterInfo *TRI,
+ unsigned &RegClass, unsigned &Cost) {
+ EVT VT = RegDefPos.GetValue();
+
+ // Special handling for untyped values. These values can only come from
+ // the expansion of custom DAG-to-DAG patterns.
+ if (VT == MVT::untyped) {
+ unsigned Opcode = RegDefPos.GetNode()->getMachineOpcode();
+ unsigned Idx = RegDefPos.GetIdx();
+ const TargetInstrDesc Desc = TII->get(Opcode);
+ const TargetRegisterClass *RC = Desc.getRegClass(Idx, TRI);
+ RegClass = RC->getID();
+ // FIXME: Cost arbitrarily set to 1 because there doesn't seem to be a
+ // better way to determine it.
+ Cost = 1;
+ } else {
+ RegClass = TLI->getRepRegClassFor(VT)->getID();
+ Cost = TLI->getRepRegClassCostFor(VT);
+ }
+}
/// Schedule - Schedule the DAG using list scheduling.
void ScheduleDAGRRList::Schedule() {
@@ -1807,8 +1834,10 @@
for (ScheduleDAGSDNodes::RegDefIter RegDefPos(PredSU, scheduleDAG);
RegDefPos.IsValid(); RegDefPos.Advance()) {
EVT VT = RegDefPos.GetValue();
- unsigned RCId = TLI->getRepRegClassFor(VT)->getID();
- unsigned Cost = TLI->getRepRegClassCostFor(VT);
+
+ unsigned RCId, Cost;
+ GetCostForDef(RegDefPos, TLI, TII, TRI, RCId, Cost);
+
if ((RegPressure[RCId] + Cost) >= RegLimit[RCId])
return true;
}
@@ -1919,9 +1948,10 @@
RegDefPos.IsValid(); RegDefPos.Advance(), --SkipRegDefs) {
if (SkipRegDefs)
continue;
- EVT VT = RegDefPos.GetValue();
- unsigned RCId = TLI->getRepRegClassFor(VT)->getID();
- RegPressure[RCId] += TLI->getRepRegClassCostFor(VT);
+
+ unsigned RCId, Cost;
+ GetCostForDef(RegDefPos, TLI, TII, TRI, RCId, Cost);
+ RegPressure[RCId] += Cost;
break;
}
}
@@ -1934,16 +1964,16 @@
RegDefPos.IsValid(); RegDefPos.Advance(), --SkipRegDefs) {
if (SkipRegDefs > 0)
continue;
- EVT VT = RegDefPos.GetValue();
- unsigned RCId = TLI->getRepRegClassFor(VT)->getID();
- if (RegPressure[RCId] < TLI->getRepRegClassCostFor(VT)) {
+ unsigned RCId, Cost;
+ GetCostForDef(RegDefPos, TLI, TII, TRI, RCId, Cost);
+ if (RegPressure[RCId] < Cost) {
// Register pressure tracking is imprecise. This can happen. But we try
// hard not to let it happen because it likely results in poor scheduling.
DEBUG(dbgs() << " SU(" << SU->NodeNum << ") has too many regdefs\n");
RegPressure[RCId] = 0;
}
else {
- RegPressure[RCId] -= TLI->getRepRegClassCostFor(VT);
+ RegPressure[RCId] -= Cost;
}
}
dumpRegPressure();
diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.h b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.h
index b5f68f3..3ad2bd6 100644
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.h
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.h
@@ -135,6 +135,14 @@
return ValueType;
}
+ const SDNode *GetNode() const {
+ return Node;
+ }
+
+ unsigned GetIdx() const {
+ return DefIdx;
+ }
+
void Advance();
private:
void InitNodeNumDefs();