constify the TargetMachine being passed through the Mips subtarget

[oota-llvm.git] / lib / CodeGen / RegisterPressure.cpp

diff --git a/lib/CodeGen/RegisterPressure.cpp b/lib/CodeGen/RegisterPressure.cpp
index 1be203f36dd18b04a79e881002ee17bdbb607abd..49c4cb0a824516310079bb613eb0400726331eba 100644 (file)
--- a/lib/CodeGen/RegisterPressure.cpp
+++ b/lib/CodeGen/RegisterPressure.cpp
@@ -41,7 +41,7 @@ static void decreaseSetPressure(std::vector<unsigned> &CurrSetPressure,
   }
 }
 
-#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD
 void llvm::dumpRegSetPressure(ArrayRef<unsigned> SetPressure,
                               const TargetRegisterInfo *TRI) {
   bool Empty = true;
@@ -55,6 +55,7 @@ void llvm::dumpRegSetPressure(ArrayRef<unsigned> SetPressure,
     dbgs() << "\n";
 }
 
+LLVM_DUMP_METHOD
 void RegisterPressure::dump(const TargetRegisterInfo *TRI) const {
   dbgs() << "Max Pressure: ";
   dumpRegSetPressure(MaxSetPressure, TRI);
@@ -68,6 +69,7 @@ void RegisterPressure::dump(const TargetRegisterInfo *TRI) const {
   dbgs() << '\n';
 }
 
+LLVM_DUMP_METHOD
 void RegPressureTracker::dump() const {
   if (!isTopClosed() || !isBottomClosed()) {
     dbgs() << "Curr Pressure: ";
@@ -75,7 +77,6 @@ void RegPressureTracker::dump() const {
   }
   P.dump(TRI);
 }
-#endif
 
 /// Increase the current pressure as impacted by these registers and bump
 /// the high water mark if needed.
@@ -147,12 +148,30 @@ void RegionPressure::openBottom(MachineBasicBlock::const_iterator PrevBottom) {
   LiveInRegs.clear();
 }
 
-const LiveInterval *RegPressureTracker::getInterval(unsigned Reg) const {
+const LiveRange *RegPressureTracker::getLiveRange(unsigned Reg) const {
   if (TargetRegisterInfo::isVirtualRegister(Reg))
     return &LIS->getInterval(Reg);
   return LIS->getCachedRegUnit(Reg);
 }
 
+void RegPressureTracker::reset() {
+  MBB = nullptr;
+  LIS = nullptr;
+
+  CurrSetPressure.clear();
+  LiveThruPressure.clear();
+  P.MaxSetPressure.clear();
+
+  if (RequireIntervals)
+    static_cast<IntervalPressure&>(P).reset();
+  else
+    static_cast<RegionPressure&>(P).reset();
+
+  LiveRegs.PhysRegs.clear();
+  LiveRegs.VirtRegs.clear();
+  UntiedDefs.clear();
+}
+
 /// Setup the RegPressureTracker.
 ///
 /// TODO: Add support for pressure without LiveIntervals.
@@ -163,8 +182,10 @@ void RegPressureTracker::init(const MachineFunction *mf,
                               MachineBasicBlock::const_iterator pos,
                               bool ShouldTrackUntiedDefs)
 {
+  reset();
+
   MF = mf;
-  TRI = MF->getTarget().getRegisterInfo();
+  TRI = MF->getSubtarget().getRegisterInfo();
   RCI = rci;
   MRI = &MF->getRegInfo();
   MBB = mbb;
@@ -177,19 +198,11 @@ void RegPressureTracker::init(const MachineFunction *mf,
 
   CurrPos = pos;
   CurrSetPressure.assign(TRI->getNumRegPressureSets(), 0);
-  LiveThruPressure.clear();
 
-  if (RequireIntervals)
-    static_cast<IntervalPressure&>(P).reset();
-  else
-    static_cast<RegionPressure&>(P).reset();
   P.MaxSetPressure = CurrSetPressure;
 
-  LiveRegs.PhysRegs.clear();
   LiveRegs.PhysRegs.setUniverse(TRI->getNumRegs());
-  LiveRegs.VirtRegs.clear();
   LiveRegs.VirtRegs.setUniverse(MRI->getNumVirtRegs());
-  UntiedDefs.clear();
   if (TrackUntiedDefs)
     UntiedDefs.setUniverse(MRI->getNumVirtRegs());
 }
@@ -486,10 +499,26 @@ bool RegPressureTracker::recede(SmallVectorImpl<unsigned> *LiveUses,
   // TODO: consider earlyclobbers?
   for (unsigned i = 0, e = RegOpers.Defs.size(); i < e; ++i) {
     unsigned Reg = RegOpers.Defs[i];
-    if (LiveRegs.erase(Reg))
-      decreaseRegPressure(Reg);
-    else
-      discoverLiveOut(Reg);
+    bool DeadDef = false;
+    if (RequireIntervals) {
+      const LiveRange *LR = getLiveRange(Reg);
+      if (LR) {
+        LiveQueryResult LRQ = LR->Query(SlotIdx);
+        DeadDef = LRQ.isDeadDef();
+      }
+    }
+    if (DeadDef) {
+      // LiveIntervals knows this is a dead even though it's MachineOperand is
+      // not flagged as such. Since this register will not be recorded as
+      // live-out, increase its PDiff value to avoid underflowing pressure.
+      if (PDiff)
+        PDiff->addPressureChange(Reg, false, MRI);
+    } else {
+      if (LiveRegs.erase(Reg))
+        decreaseRegPressure(Reg);
+      else
+        discoverLiveOut(Reg);
+    }
   }
 
   // Generate liveness for uses.
@@ -498,10 +527,10 @@ bool RegPressureTracker::recede(SmallVectorImpl<unsigned> *LiveUses,
     if (!LiveRegs.contains(Reg)) {
       // Adjust liveouts if LiveIntervals are available.
       if (RequireIntervals) {
-        const LiveInterval *LI = getInterval(Reg);
-        // Check if this LR is killed and not redefined here.
-        if (LI && !LI->isKilledAtInstr(SlotIdx)
-            && !LI->isDefinedByInstr(SlotIdx)) {
+        const LiveRange *LR = getLiveRange(Reg);
+        if (LR) {
+          LiveQueryResult LRQ = LR->Query(SlotIdx);
+          if (!LRQ.isKill() && !LRQ.valueDefined())
             discoverLiveOut(Reg);
         }
       }
@@ -557,8 +586,8 @@ bool RegPressureTracker::advance() {
     // Kill liveness at last uses.
     bool lastUse = false;
     if (RequireIntervals) {
-      const LiveInterval *LI = getInterval(Reg);
-      lastUse = LI && LI->isKilledAtInstr(SlotIdx);
+      const LiveRange *LR = getLiveRange(Reg);
+      lastUse = LR && LR->Query(SlotIdx).isKill();
     }
     else {
       // Allocatable physregs are always single-use before register rewriting.
@@ -690,8 +719,19 @@ void RegPressureTracker::bumpUpwardPressure(const MachineInstr *MI) {
   // Kill liveness at live defs.
   for (unsigned i = 0, e = RegOpers.Defs.size(); i < e; ++i) {
     unsigned Reg = RegOpers.Defs[i];
-    if (!containsReg(RegOpers.Uses, Reg))
-      decreaseRegPressure(Reg);
+    bool DeadDef = false;
+    if (RequireIntervals) {
+      const LiveRange *LR = getLiveRange(Reg);
+      if (LR) {
+        SlotIndex SlotIdx = LIS->getInstructionIndex(MI);
+        LiveQueryResult LRQ = LR->Query(SlotIdx);
+        DeadDef = LRQ.isDeadDef();
+      }
+    }
+    if (!DeadDef) {
+      if (!containsReg(RegOpers.Uses, Reg))
+        decreaseRegPressure(Reg);
+    }
   }
   // Generate liveness for uses.
   for (unsigned i = 0, e = RegOpers.Uses.size(); i < e; ++i) {
@@ -843,9 +883,9 @@ static bool findUseBetween(unsigned Reg,
                            SlotIndex PriorUseIdx, SlotIndex NextUseIdx,
                            const MachineRegisterInfo *MRI,
                            const LiveIntervals *LIS) {
-  for (MachineRegisterInfo::use_nodbg_iterator
-         UI = MRI->use_nodbg_begin(Reg), UE = MRI->use_nodbg_end();
-         UI != UE; UI.skipInstruction()) {
+  for (MachineRegisterInfo::use_instr_nodbg_iterator
+       UI = MRI->use_instr_nodbg_begin(Reg),
+       UE = MRI->use_instr_nodbg_end(); UI != UE; ++UI) {
       const MachineInstr* MI = &*UI;
       if (MI->isDebugValue())
         continue;
@@ -881,10 +921,12 @@ void RegPressureTracker::bumpDownwardPressure(const MachineInstr *MI) {
       // FIXME: allow the caller to pass in the list of vreg uses that remain
       // to be bottom-scheduled to avoid searching uses at each query.
       SlotIndex CurrIdx = getCurrSlot();
-      const LiveInterval *LI = getInterval(Reg);
-      if (LI && LI->isKilledAtInstr(SlotIdx)
-          && !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS)) {
-        decreaseRegPressure(Reg);
+      const LiveRange *LR = getLiveRange(Reg);
+      if (LR) {
+        LiveQueryResult LRQ = LR->Query(SlotIdx);
+        if (LRQ.isKill() && !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS)) {
+          decreaseRegPressure(Reg);
+        }
       }
     }
     else if (!TargetRegisterInfo::isVirtualRegister(Reg)) {