Vendor import of llvm trunk r161861:

http://llvm.org/svn/llvm-project/llvm/trunk@161861

1 files changed, 210 insertions, 0 deletions

diff --git a/lib/CodeGen/TargetInstrInfoImpl.cpp b/lib/CodeGen/TargetInstrInfoImpl.cpp
index 2beb928..ddee6b2 100644
--- a/lib/CodeGen/TargetInstrInfoImpl.cpp
+++ b/lib/CodeGen/TargetInstrInfoImpl.cpp
@@ -501,6 +501,14 @@ CreateTargetHazardRecognizer(const TargetMachine *TM,
   return new ScheduleHazardRecognizer();
 }
 
+// Default implementation of CreateTargetMIHazardRecognizer.
+ScheduleHazardRecognizer *TargetInstrInfoImpl::
+CreateTargetMIHazardRecognizer(const InstrItineraryData *II,
+                               const ScheduleDAG *DAG) const {
+  return (ScheduleHazardRecognizer *)
+    new ScoreboardHazardRecognizer(II, DAG, "misched");
+}
+
 // Default implementation of CreateTargetPostRAHazardRecognizer.
 ScheduleHazardRecognizer *TargetInstrInfoImpl::
 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
@@ -509,6 +517,10 @@ CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
     new ScoreboardHazardRecognizer(II, DAG, "post-RA-sched");
 }
 
+//===----------------------------------------------------------------------===//
+//  SelectionDAG latency interface.
+//===----------------------------------------------------------------------===//
+
 int
 TargetInstrInfoImpl::getOperandLatency(const InstrItineraryData *ItinData,
                                        SDNode *DefNode, unsigned DefIdx,
@@ -537,3 +549,201 @@ int TargetInstrInfoImpl::getInstrLatency(const InstrItineraryData *ItinData,
   return ItinData->getStageLatency(get(N->getMachineOpcode()).getSchedClass());
 }
 
+//===----------------------------------------------------------------------===//
+//  MachineInstr latency interface.
+//===----------------------------------------------------------------------===//
+
+unsigned
+TargetInstrInfoImpl::getNumMicroOps(const InstrItineraryData *ItinData,
+                                    const MachineInstr *MI) const {
+  if (!ItinData || ItinData->isEmpty())
+    return 1;
+
+  unsigned Class = MI->getDesc().getSchedClass();
+  int UOps = ItinData->Itineraries[Class].NumMicroOps;
+  if (UOps >= 0)
+    return UOps;
+
+  // The # of u-ops is dynamically determined. The specific target should
+  // override this function to return the right number.
+  return 1;
+}
+
+/// Return the default expected latency for a def based on it's opcode.
+unsigned TargetInstrInfo::defaultDefLatency(const MCSchedModel *SchedModel,
+                                            const MachineInstr *DefMI) const {
+  if (DefMI->mayLoad())
+    return SchedModel->LoadLatency;
+  if (isHighLatencyDef(DefMI->getOpcode()))
+    return SchedModel->HighLatency;
+  return 1;
+}
+
+unsigned TargetInstrInfoImpl::
+getInstrLatency(const InstrItineraryData *ItinData,
+                const MachineInstr *MI,
+                unsigned *PredCost) const {
+  // Default to one cycle for no itinerary. However, an "empty" itinerary may
+  // still have a MinLatency property, which getStageLatency checks.
+  if (!ItinData)
+    return MI->mayLoad() ? 2 : 1;
+
+  return ItinData->getStageLatency(MI->getDesc().getSchedClass());
+}
+
+bool TargetInstrInfoImpl::hasLowDefLatency(const InstrItineraryData *ItinData,
+                                           const MachineInstr *DefMI,
+                                           unsigned DefIdx) const {
+  if (!ItinData || ItinData->isEmpty())
+    return false;
+
+  unsigned DefClass = DefMI->getDesc().getSchedClass();
+  int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
+  return (DefCycle != -1 && DefCycle <= 1);
+}
+
+/// Both DefMI and UseMI must be valid.  By default, call directly to the
+/// itinerary. This may be overriden by the target.
+int TargetInstrInfoImpl::
+getOperandLatency(const InstrItineraryData *ItinData,
+                  const MachineInstr *DefMI, unsigned DefIdx,
+                  const MachineInstr *UseMI, unsigned UseIdx) const {
+  unsigned DefClass = DefMI->getDesc().getSchedClass();
+  unsigned UseClass = UseMI->getDesc().getSchedClass();
+  return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx);
+}
+
+/// If we can determine the operand latency from the def only, without itinerary
+/// lookup, do so. Otherwise return -1.
+static int computeDefOperandLatency(
+  const TargetInstrInfo *TII, const InstrItineraryData *ItinData,
+  const MachineInstr *DefMI, bool FindMin) {
+
+  // Let the target hook getInstrLatency handle missing itineraries.
+  if (!ItinData)
+    return TII->getInstrLatency(ItinData, DefMI);
+
+  // Return a latency based on the itinerary properties and defining instruction
+  // if possible. Some common subtargets don't require per-operand latency,
+  // especially for minimum latencies.
+  if (FindMin) {
+    // If MinLatency is valid, call getInstrLatency. This uses Stage latency if
+    // it exists before defaulting to MinLatency.
+    if (ItinData->SchedModel->MinLatency >= 0)
+      return TII->getInstrLatency(ItinData, DefMI);
+
+    // If MinLatency is invalid, OperandLatency is interpreted as MinLatency.
+    // For empty itineraries, short-cirtuit the check and default to one cycle.
+    if (ItinData->isEmpty())
+      return 1;
+  }
+  else if(ItinData->isEmpty())
+    return TII->defaultDefLatency(ItinData->SchedModel, DefMI);
+
+  // ...operand lookup required
+  return -1;
+}
+
+/// computeOperandLatency - Compute and return the latency of the given data
+/// dependent def and use when the operand indices are already known.
+///
+/// FindMin may be set to get the minimum vs. expected latency.
+unsigned TargetInstrInfo::
+computeOperandLatency(const InstrItineraryData *ItinData,
+                      const MachineInstr *DefMI, unsigned DefIdx,
+                      const MachineInstr *UseMI, unsigned UseIdx,
+                      bool FindMin) const {
+
+  int DefLatency = computeDefOperandLatency(this, ItinData, DefMI, FindMin);
+  if (DefLatency >= 0)
+    return DefLatency;
+
+  assert(ItinData && !ItinData->isEmpty() && "computeDefOperandLatency fail");
+
+  int OperLatency = getOperandLatency(ItinData, DefMI, DefIdx, UseMI, UseIdx);
+  if (OperLatency >= 0)
+    return OperLatency;
+
+  // No operand latency was found.
+  unsigned InstrLatency = getInstrLatency(ItinData, DefMI);
+
+  // Expected latency is the max of the stage latency and itinerary props.
+  if (!FindMin)
+    InstrLatency = std::max(InstrLatency,
+                            defaultDefLatency(ItinData->SchedModel, DefMI));
+  return InstrLatency;
+}
+
+/// computeOperandLatency - Compute and return the latency of the given data
+/// dependent def and use. DefMI must be a valid def. UseMI may be NULL for an
+/// unknown use. Depending on the subtarget's itinerary properties, this may or
+/// may not need to call getOperandLatency().
+///
+/// FindMin may be set to get the minimum vs. expected latency. Minimum
+/// latency is used for scheduling groups, while expected latency is for
+/// instruction cost and critical path.
+///
+/// For most subtargets, we don't need DefIdx or UseIdx to compute min latency.
+/// DefMI must be a valid definition, but UseMI may be NULL for an unknown use.
+unsigned TargetInstrInfo::
+computeOperandLatency(const InstrItineraryData *ItinData,
+                      const TargetRegisterInfo *TRI,
+                      const MachineInstr *DefMI, const MachineInstr *UseMI,
+                      unsigned Reg, bool FindMin) const {
+
+  int DefLatency = computeDefOperandLatency(this, ItinData, DefMI, FindMin);
+  if (DefLatency >= 0)
+    return DefLatency;
+
+  assert(ItinData && !ItinData->isEmpty() && "computeDefOperandLatency fail");
+
+  // Find the definition of the register in the defining instruction.
+  int DefIdx = DefMI->findRegisterDefOperandIdx(Reg);
+  if (DefIdx != -1) {
+    const MachineOperand &MO = DefMI->getOperand(DefIdx);
+    if (MO.isReg() && MO.isImplicit() &&
+        DefIdx >= (int)DefMI->getDesc().getNumOperands()) {
+      // This is an implicit def, getOperandLatency() won't return the correct
+      // latency. e.g.
+      //   %D6<def>, %D7<def> = VLD1q16 %R2<kill>, 0, ..., %Q3<imp-def>
+      //   %Q1<def> = VMULv8i16 %Q1<kill>, %Q3<kill>, ...
+      // What we want is to compute latency between def of %D6/%D7 and use of
+      // %Q3 instead.
+      unsigned Op2 = DefMI->findRegisterDefOperandIdx(Reg, false, true, TRI);
+      if (DefMI->getOperand(Op2).isReg())
+        DefIdx = Op2;
+    }
+    // For all uses of the register, calculate the maxmimum latency
+    int OperLatency = -1;
+
+    // UseMI is null, then it must be a scheduling barrier.
+    if (!UseMI) {
+      unsigned DefClass = DefMI->getDesc().getSchedClass();
+      OperLatency = ItinData->getOperandCycle(DefClass, DefIdx);
+    }
+    else {
+      for (unsigned i = 0, e = UseMI->getNumOperands(); i != e; ++i) {
+        const MachineOperand &MO = UseMI->getOperand(i);
+        if (!MO.isReg() || !MO.isUse())
+          continue;
+        unsigned MOReg = MO.getReg();
+        if (MOReg != Reg)
+          continue;
+
+        int UseCycle = getOperandLatency(ItinData, DefMI, DefIdx, UseMI, i);
+        OperLatency = std::max(OperLatency, UseCycle);
+      }
+    }
+    // If we found an operand latency, we're done.
+    if (OperLatency >= 0)
+      return OperLatency;
+  }
+  // No operand latency was found.
+  unsigned InstrLatency = getInstrLatency(ItinData, DefMI);
+
+  // Expected latency is the max of the stage latency and itinerary props.
+  if (!FindMin)
+    InstrLatency = std::max(InstrLatency,
+                            defaultDefLatency(ItinData->SchedModel, DefMI));
+  return InstrLatency;
+}