Revert "[WinEH] Add an EH registration and state insertion pass for 32-bit x86"

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

diff --git a/lib/CodeGen/RegisterPressure.cpp b/lib/CodeGen/RegisterPressure.cpp
index 2f273a3fd3727a2fc79054b3cc05847a7a2a096a..36341039acf8ce0f5aaf8ddfe0dea725c63b28ba 100644 (file)
--- a/lib/CodeGen/RegisterPressure.cpp
+++ b/lib/CodeGen/RegisterPressure.cpp
@@ -19,7 +19,6 @@
 #include "llvm/CodeGen/RegisterClassInfo.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetMachine.h"
 
 using namespace llvm;
 
@@ -41,7 +40,7 @@ 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 +54,7 @@ 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 +68,7 @@ void RegisterPressure::dump(const TargetRegisterInfo *TRI) const {
   dbgs() << '\n';
 }
 
+LLVM_DUMP_METHOD
 void RegPressureTracker::dump() const {
   if (!isTopClosed() || !isBottomClosed()) {
     dbgs() << "Curr Pressure: ";
@@ -75,7 +76,6 @@ 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.
@@ -147,15 +147,15 @@ 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 = 0;
-  LIS = 0;
+  MBB = nullptr;
+  LIS = nullptr;
 
   CurrSetPressure.clear();
   LiveThruPressure.clear();
@@ -184,7 +184,7 @@ void RegPressureTracker::init(const MachineFunction *mf,
   reset();
 
   MF = mf;
-  TRI = MF->getTarget().getRegisterInfo();
+  TRI = MF->getSubtarget().getRegisterInfo();
   RCI = rci;
   MRI = &MF->getRegInfo();
   MBB = mbb;
@@ -304,6 +304,7 @@ static bool containsReg(ArrayRef<unsigned> RegUnits, unsigned RegUnit) {
   return std::find(RegUnits.begin(), RegUnits.end(), RegUnit) != RegUnits.end();
 }
 
+namespace {
 /// Collect this instruction's unique uses and defs into SmallVectors for
 /// processing defs and uses in order.
 ///
@@ -354,6 +355,7 @@ protected:
     }
   }
 };
+} // namespace
 
 /// Collect physical and virtual register operands.
 static void collectOperands(const MachineInstr *MI,
@@ -498,10 +500,26 @@ 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.
@@ -510,10 +528,9 @@ 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) {
-          LiveQueryResult LRQ = LI->Query(SlotIdx);
+        const LiveRange *LR = getLiveRange(Reg);
+        if (LR) {
+          LiveQueryResult LRQ = LR->Query(SlotIdx);
           if (!LRQ.isKill() && !LRQ.valueDefined())
             discoverLiveOut(Reg);
         }
@@ -570,8 +587,8 @@ bool RegPressureTracker::advance() {
     // Kill liveness at last uses.
     bool lastUse = false;
     if (RequireIntervals) {
-      const LiveInterval *LI = getInterval(Reg);
-      lastUse = LI && LI->Query(SlotIdx).isKill();
+      const LiveRange *LR = getLiveRange(Reg);
+      lastUse = LR && LR->Query(SlotIdx).isKill();
     }
     else {
       // Allocatable physregs are always single-use before register rewriting.
@@ -703,8 +720,19 @@ 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) {
@@ -856,9 +884,9 @@ 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;
@@ -894,11 +922,12 @@ 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) {
-        LiveQueryResult LRQ = LI->Query(SlotIdx);
-        if (LRQ.isKill() && !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS))
+      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)) {