Use individual register classes when spilling snippets.

The main register class may have been inflated by live range splitting, so that
register class is not necessarily valid for the snippet instructions.

Use the original register class for the stack slot interval.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128351 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 28 insertions, 24 deletions

diff --git a/lib/CodeGen/InlineSpiller.cpp b/lib/CodeGen/InlineSpiller.cpp
index 78a6ca62d9..c5994cba14 100644
--- a/lib/CodeGen/InlineSpiller.cpp
+++ b/lib/CodeGen/InlineSpiller.cpp
@@ -48,7 +48,7 @@ class InlineSpiller : public Spiller {
 
   // Variables that are valid during spill(), but used by multiple methods.
   LiveRangeEdit *Edit;
-  const TargetRegisterClass *RC;
+  LiveInterval *StackInt;
   int StackSlot;
   unsigned Original;
 
@@ -431,12 +431,12 @@ bool InlineSpiller::hoistSpill(LiveInterval &SpillLI, MachineInstr *CopyMI) {
   // Conservatively extend the stack slot range to the range of the original
   // value. We may be able to do better with stack slot coloring by being more
   // careful here.
-  LiveInterval &StackInt = LSS.getInterval(StackSlot);
+  assert(StackInt && "No stack slot assigned yet.");
   LiveInterval &OrigLI = LIS.getInterval(Original);
   VNInfo *OrigVNI = OrigLI.getVNInfoAt(Idx);
-  StackInt.MergeValueInAsValue(OrigLI, OrigVNI, StackInt.getValNumInfo(0));
+  StackInt->MergeValueInAsValue(OrigLI, OrigVNI, StackInt->getValNumInfo(0));
   DEBUG(dbgs() << "\tmerged orig valno " << OrigVNI->id << ": "
-               << StackInt << '\n');
+               << *StackInt << '\n');
 
   // Already spilled everywhere.
   if (SVI.AllDefsAreReloads)
@@ -455,7 +455,8 @@ bool InlineSpiller::hoistSpill(LiveInterval &SpillLI, MachineInstr *CopyMI) {
     ++MII;
   }
   // Insert spill without kill flag immediately after def.
-  TII.storeRegToStackSlot(*MBB, MII, SVI.SpillReg, false, StackSlot, RC, &TRI);
+  TII.storeRegToStackSlot(*MBB, MII, SVI.SpillReg, false, StackSlot,
+                          MRI.getRegClass(SVI.SpillReg), &TRI);
   --MII; // Point to store instruction.
   LIS.InsertMachineInstrInMaps(MII);
   VRM.addSpillSlotUse(StackSlot, MII);
@@ -469,7 +470,7 @@ void InlineSpiller::eliminateRedundantSpills(LiveInterval &SLI, VNInfo *VNI) {
   assert(VNI && "Missing value");
   SmallVector<std::pair<LiveInterval*, VNInfo*>, 8> WorkList;
   WorkList.push_back(std::make_pair(&SLI, VNI));
-  LiveInterval &StackInt = LSS.getInterval(StackSlot);
+  assert(StackInt && "No stack slot assigned yet.");
 
   do {
     LiveInterval *LI;
@@ -483,8 +484,8 @@ void InlineSpiller::eliminateRedundantSpills(LiveInterval &SLI, VNInfo *VNI) {
       continue;
 
     // Add all of VNI's live range to StackInt.
-    StackInt.MergeValueInAsValue(*LI, VNI, StackInt.getValNumInfo(0));
-    DEBUG(dbgs() << "Merged to stack int: " << StackInt << '\n');
+    StackInt->MergeValueInAsValue(*LI, VNI, StackInt->getValNumInfo(0));
+    DEBUG(dbgs() << "Merged to stack int: " << *StackInt << '\n');
 
     // Find all spills and copies of VNI.
     for (MachineRegisterInfo::use_nodbg_iterator UI = MRI.use_nodbg_begin(Reg);
@@ -723,7 +724,8 @@ void InlineSpiller::insertReload(LiveInterval &NewLI,
                                  MachineBasicBlock::iterator MI) {
   MachineBasicBlock &MBB = *MI->getParent();
   SlotIndex Idx = LIS.getInstructionIndex(MI).getDefIndex();
-  TII.loadRegFromStackSlot(MBB, MI, NewLI.reg, StackSlot, RC, &TRI);
+  TII.loadRegFromStackSlot(MBB, MI, NewLI.reg, StackSlot,
+                           MRI.getRegClass(NewLI.reg), &TRI);
   --MI; // Point to load instruction.
   SlotIndex LoadIdx = LIS.InsertMachineInstrInMaps(MI).getDefIndex();
   VRM.addSpillSlotUse(StackSlot, MI);
@@ -744,7 +746,8 @@ void InlineSpiller::insertSpill(LiveInterval &NewLI, const LiveInterval &OldLI,
   assert(VNI && VNI->def.getDefIndex() == Idx && "Inconsistent VNInfo");
   Idx = VNI->def;
 
-  TII.storeRegToStackSlot(MBB, ++MI, NewLI.reg, true, StackSlot, RC, &TRI);
+  TII.storeRegToStackSlot(MBB, ++MI, NewLI.reg, true, StackSlot,
+                          MRI.getRegClass(NewLI.reg), &TRI);
   --MI; // Point to store instruction.
   SlotIndex StoreIdx = LIS.InsertMachineInstrInMaps(MI).getDefIndex();
   VRM.addSpillSlotUse(StackSlot, MI);
@@ -818,7 +821,7 @@ void InlineSpiller::spillAroundUses(unsigned Reg) {
 
     // Allocate interval around instruction.
     // FIXME: Infer regclass from instruction alone.
-    LiveInterval &NewLI = Edit->create(LIS, VRM);
+    LiveInterval &NewLI = Edit->createFrom(Reg, LIS, VRM);
     NewLI.markNotSpillable();
 
     if (Reads)
@@ -853,6 +856,7 @@ void InlineSpiller::spill(LiveRangeEdit &edit) {
   // Share a stack slot among all descendants of Original.
   Original = VRM.getOriginal(edit.getReg());
   StackSlot = VRM.getStackSlot(Original);
+  StackInt = 0;
 
   DEBUG(dbgs() << "Inline spilling "
                << MRI.getRegClass(edit.getReg())->getName()
@@ -870,22 +874,22 @@ void InlineSpiller::spill(LiveRangeEdit &edit) {
   if (Edit->getParent().empty())
     return;
 
-  RC = MRI.getRegClass(edit.getReg());
-
-  if (StackSlot == VirtRegMap::NO_STACK_SLOT)
+  // Update LiveStacks now that we are committed to spilling.
+  if (StackSlot == VirtRegMap::NO_STACK_SLOT) {
     StackSlot = VRM.assignVirt2StackSlot(Original);
+    StackInt = &LSS.getOrCreateInterval(StackSlot, MRI.getRegClass(Original));
+    StackInt->getNextValue(SlotIndex(), 0, LSS.getVNInfoAllocator());
+  } else
+    StackInt = &LSS.getInterval(StackSlot);
 
   if (Original != edit.getReg())
     VRM.assignVirt2StackSlot(edit.getReg(), StackSlot);
 
-  // Update LiveStacks now that we are committed to spilling.
-  LiveInterval &stacklvr = LSS.getOrCreateInterval(StackSlot, RC);
-  if (!stacklvr.hasAtLeastOneValue())
-    stacklvr.getNextValue(SlotIndex(), 0, LSS.getVNInfoAllocator());
+  assert(StackInt->getNumValNums() == 1 && "Bad stack interval values");
   for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i)
-    stacklvr.MergeRangesInAsValue(LIS.getInterval(RegsToSpill[i]),
-                                  stacklvr.getValNumInfo(0));
-  DEBUG(dbgs() << "Merged spilled regs: " << stacklvr << '\n');
+    StackInt->MergeRangesInAsValue(LIS.getInterval(RegsToSpill[i]),
+                                   StackInt->getValNumInfo(0));
+  DEBUG(dbgs() << "Merged spilled regs: " << *StackInt << '\n');
 
   // Spill around uses of all RegsToSpill.
   for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i)
diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
index 0846961f5b..0e03137c86 100644
--- a/lib/CodeGen/LiveRangeEdit.h
+++ b/lib/CodeGen/LiveRangeEdit.h
@@ -65,9 +65,6 @@ private:
   /// live range trimmed or entirely removed.
   SmallPtrSet<const VNInfo*,4> rematted_;
 
-  /// createFrom - Create a new virtual register based on OldReg.
-  LiveInterval &createFrom(unsigned, LiveIntervals&, VirtRegMap &);
-
   /// scanRemattable - Identify the parent_ values that may rematerialize.
   void scanRemattable(LiveIntervals &lis,
                       const TargetInstrInfo &tii,
@@ -113,6 +110,9 @@ public:
     return uselessRegs_;
   }
 
+  /// createFrom - Create a new virtual register based on OldReg.
+  LiveInterval &createFrom(unsigned OldReg, LiveIntervals&, VirtRegMap&);
+
   /// create - Create a new register with the same class and original slot as
   /// parent.
   LiveInterval &create(LiveIntervals &LIS, VirtRegMap &VRM) {