1 files changed, 57 insertions, 20 deletions

diff --git a/contrib/llvm-project/llvm/lib/CodeGen/LiveDebugVariables.cpp b/contrib/llvm-project/llvm/lib/CodeGen/LiveDebugVariables.cpp
index 2cc547a6b741..5b20a2482b7b 100644
--- a/contrib/llvm-project/llvm/lib/CodeGen/LiveDebugVariables.cpp
+++ b/contrib/llvm-project/llvm/lib/CodeGen/LiveDebugVariables.cpp
@@ -100,27 +100,28 @@ enum : unsigned { UndefLocNo = ~0U };
 /// usage of the location.
 class DbgValueLocation {
 public:
-  DbgValueLocation(unsigned LocNo)
-      : LocNo(LocNo) {
+  DbgValueLocation(unsigned LocNo, bool WasIndirect)
+      : LocNo(LocNo), WasIndirect(WasIndirect) {
     static_assert(sizeof(*this) == sizeof(unsigned), "bad bitfield packing");
     assert(locNo() == LocNo && "location truncation");
   }
 
-  DbgValueLocation() : LocNo(0) {}
+  DbgValueLocation() : LocNo(0), WasIndirect(0) {}
 
   unsigned locNo() const {
     // Fix up the undef location number, which gets truncated.
     return LocNo == INT_MAX ? UndefLocNo : LocNo;
   }
+  bool wasIndirect() const { return WasIndirect; }
   bool isUndef() const { return locNo() == UndefLocNo; }
 
   DbgValueLocation changeLocNo(unsigned NewLocNo) const {
-    return DbgValueLocation(NewLocNo);
+    return DbgValueLocation(NewLocNo, WasIndirect);
   }
 
   friend inline bool operator==(const DbgValueLocation &LHS,
                                 const DbgValueLocation &RHS) {
-    return LHS.LocNo == RHS.LocNo;
+    return LHS.LocNo == RHS.LocNo && LHS.WasIndirect == RHS.WasIndirect;
   }
 
   friend inline bool operator!=(const DbgValueLocation &LHS,
@@ -129,7 +130,8 @@ public:
   }
 
 private:
-  unsigned LocNo;
+  unsigned LocNo : 31;
+  unsigned WasIndirect : 1;
 };
 
 /// Map of where a user value is live, and its location.
@@ -166,6 +168,10 @@ class UserValue {
   /// Map of slot indices where this value is live.
   LocMap locInts;
 
+  /// Set of interval start indexes that have been trimmed to the
+  /// lexical scope.
+  SmallSet<SlotIndex, 2> trimmedDefs;
+
   /// Insert a DBG_VALUE into MBB at Idx for LocNo.
   void insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx,
                         SlotIndex StopIdx, DbgValueLocation Loc, bool Spilled,
@@ -279,8 +285,8 @@ public:
   void mapVirtRegs(LDVImpl *LDV);
 
   /// Add a definition point to this value.
-  void addDef(SlotIndex Idx, const MachineOperand &LocMO) {
-    DbgValueLocation Loc(getLocationNo(LocMO));
+  void addDef(SlotIndex Idx, const MachineOperand &LocMO, bool IsIndirect) {
+    DbgValueLocation Loc(getLocationNo(LocMO), IsIndirect);
     // Add a singular (Idx,Idx) -> Loc mapping.
     LocMap::iterator I = locInts.find(Idx);
     if (!I.valid() || I.start() != Idx)
@@ -315,10 +321,11 @@ public:
   ///
   /// \param LI Scan for copies of the value in LI->reg.
   /// \param LocNo Location number of LI->reg.
+  /// \param WasIndirect Indicates if the original use of LI->reg was indirect
   /// \param Kills Points where the range of LocNo could be extended.
   /// \param [in,out] NewDefs Append (Idx, LocNo) of inserted defs here.
   void addDefsFromCopies(
-      LiveInterval *LI, unsigned LocNo,
+      LiveInterval *LI, unsigned LocNo, bool WasIndirect,
       const SmallVectorImpl<SlotIndex> &Kills,
       SmallVectorImpl<std::pair<SlotIndex, DbgValueLocation>> &NewDefs,
       MachineRegisterInfo &MRI, LiveIntervals &LIS);
@@ -538,6 +545,8 @@ void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) {
       OS << "undef";
     else {
       OS << I.value().locNo();
+      if (I.value().wasIndirect())
+        OS << " ind";
     }
   }
   for (unsigned i = 0, e = locations.size(); i != e; ++i) {
@@ -646,18 +655,19 @@ bool LDVImpl::handleDebugValue(MachineInstr &MI, SlotIndex Idx) {
   }
 
   // Get or create the UserValue for (variable,offset) here.
-  assert(!MI.getOperand(1).isImm() && "DBG_VALUE with indirect flag before "
-                                      "LiveDebugVariables");
+  bool IsIndirect = MI.getOperand(1).isImm();
+  if (IsIndirect)
+    assert(MI.getOperand(1).getImm() == 0 && "DBG_VALUE with nonzero offset");
   const DILocalVariable *Var = MI.getDebugVariable();
   const DIExpression *Expr = MI.getDebugExpression();
   UserValue *UV =
       getUserValue(Var, Expr, MI.getDebugLoc());
   if (!Discard)
-    UV->addDef(Idx, MI.getOperand(0));
+    UV->addDef(Idx, MI.getOperand(0), IsIndirect);
   else {
     MachineOperand MO = MachineOperand::CreateReg(0U, false);
     MO.setIsDebug();
-    UV->addDef(Idx, MO);
+    UV->addDef(Idx, MO, false);
   }
   return true;
 }
@@ -765,7 +775,7 @@ void UserValue::extendDef(SlotIndex Idx, DbgValueLocation Loc, LiveRange *LR,
 }
 
 void UserValue::addDefsFromCopies(
-    LiveInterval *LI, unsigned LocNo,
+    LiveInterval *LI, unsigned LocNo, bool WasIndirect,
     const SmallVectorImpl<SlotIndex> &Kills,
     SmallVectorImpl<std::pair<SlotIndex, DbgValueLocation>> &NewDefs,
     MachineRegisterInfo &MRI, LiveIntervals &LIS) {
@@ -829,7 +839,7 @@ void UserValue::addDefsFromCopies(
       MachineInstr *CopyMI = LIS.getInstructionFromIndex(DstVNI->def);
       assert(CopyMI && CopyMI->isCopy() && "Bad copy value");
       unsigned LocNo = getLocationNo(CopyMI->getOperand(0));
-      DbgValueLocation NewLoc(LocNo);
+      DbgValueLocation NewLoc(LocNo, WasIndirect);
       I.insert(Idx, Idx.getNextSlot(), NewLoc);
       NewDefs.push_back(std::make_pair(Idx, NewLoc));
       break;
@@ -877,7 +887,8 @@ void UserValue::computeIntervals(MachineRegisterInfo &MRI,
       // sub-register in that regclass). For now, simply skip handling copies if
       // a sub-register is involved.
       if (LI && !LocMO.getSubReg())
-        addDefsFromCopies(LI, Loc.locNo(), Kills, Defs, MRI, LIS);
+        addDefsFromCopies(LI, Loc.locNo(), Loc.wasIndirect(), Kills, Defs, MRI,
+                          LIS);
       continue;
     }
 
@@ -910,6 +921,11 @@ void UserValue::computeIntervals(MachineRegisterInfo &MRI,
     SlotIndex RStart = LIS.getInstructionIndex(*Range.first);
     SlotIndex REnd = LIS.getInstructionIndex(*Range.second);
 
+    // Variable locations at the first instruction of a block should be
+    // based on the block's SlotIndex, not the first instruction's index.
+    if (Range.first == Range.first->getParent()->begin())
+      RStart = LIS.getSlotIndexes()->getIndexBefore(*Range.first);
+
     // At the start of each iteration I has been advanced so that
     // I.stop() >= PrevEnd. Check for overlap.
     if (PrevEnd && I.start() < PrevEnd) {
@@ -922,7 +938,8 @@ void UserValue::computeIntervals(MachineRegisterInfo &MRI,
       ++I;
 
       // If the interval also overlaps the start of the "next" (i.e.
-      // current) range create a new interval for the remainder
+      // current) range create a new interval for the remainder (which
+      // may be further trimmed).
       if (RStart < IStop)
         I.insert(RStart, IStop, Loc);
     }
@@ -932,6 +949,13 @@ void UserValue::computeIntervals(MachineRegisterInfo &MRI,
     if (!I.valid())
       return;
 
+    if (I.start() < RStart) {
+      // Interval start overlaps range - trim to the scope range.
+      I.setStartUnchecked(RStart);
+      // Remember that this interval was trimmed.
+      trimmedDefs.insert(RStart);
+    }
+
     // The end of a lexical scope range is the last instruction in the
     // range. To convert to an interval we need the index of the
     // instruction after it.
@@ -1306,14 +1330,21 @@ void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx,
   // that the original virtual register was a pointer. Also, add the stack slot
   // offset for the spilled register to the expression.
   const DIExpression *Expr = Expression;
-  if (Spilled)
-    Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, SpillOffset);
+  uint8_t DIExprFlags = DIExpression::ApplyOffset;
+  bool IsIndirect = Loc.wasIndirect();
+  if (Spilled) {
+    if (IsIndirect)
+      DIExprFlags |= DIExpression::DerefAfter;
+    Expr =
+        DIExpression::prepend(Expr, DIExprFlags, SpillOffset);
+    IsIndirect = true;
+  }
 
   assert((!Spilled || MO.isFI()) && "a spilled location must be a frame index");
 
   do {
     BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE),
-            Spilled, MO, Variable, Expr);
+            IsIndirect, MO, Variable, Expr);
 
     // Continue and insert DBG_VALUES after every redefinition of register
     // associated with the debug value within the range
@@ -1345,6 +1376,12 @@ void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS,
     bool Spilled = SpillIt != SpillOffsets.end();
     unsigned SpillOffset = Spilled ? SpillIt->second : 0;
 
+    // If the interval start was trimmed to the lexical scope insert the
+    // DBG_VALUE at the previous index (otherwise it appears after the
+    // first instruction in the range).
+    if (trimmedDefs.count(Start))
+      Start = Start.getPrevIndex();
+
     LLVM_DEBUG(dbgs() << "\t[" << Start << ';' << Stop << "):" << Loc.locNo());
     MachineFunction::iterator MBB = LIS.getMBBFromIndex(Start)->getIterator();
     SlotIndex MBBEnd = LIS.getMBBEndIdx(&*MBB);