Subzero: Refactor tracking of Defs and block-local Variables.

src/IceInst.cpp

 //===- subzero/src/IceInst.cpp - High-level instruction implementation ----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the Inst class, primarily the various
@@ skipping 93 matching lines @@
         }
         Mask >>= 1;
         if (Mask == 0)
           return false; // another early-exit optimization
       }
     }
   }
   return false;
 }
 
-void Inst::updateVars(CfgNode *Node) {
-  if (Dest)
-    Dest->setDefinition(this, Node);
-
-  for (SizeT I = 0; I < getSrcSize(); ++I) {
-    Operand *Src = getSrc(I);
-    SizeT NumVars = Src->getNumVars();
-    for (SizeT J = 0; J < NumVars; ++J) {
-      Variable *Var = Src->getVar(J);
-      Var->setUse(this, Node);
-    }
-  }
-}
-
-void Inst::livenessLightweight(llvm::BitVector &Live) {
+void Inst::livenessLightweight(Cfg *Func, llvm::BitVector &Live) {
   assert(!isDeleted());
   if (llvm::isa<InstFakeKill>(this))
     return;
   resetLastUses();
   SizeT VarIndex = 0;
   for (SizeT I = 0; I < getSrcSize(); ++I) {
     Operand *Src = getSrc(I);
     SizeT NumVars = Src->getNumVars();
     for (SizeT J = 0; J < NumVars; ++J, ++VarIndex) {
       const Variable *Var = Src->getVar(J);
-      if (Var->isMultiblockLife())
+      if (Func->getVMetadata()->isMultiBlock(Var))
         continue;
       SizeT Index = Var->getIndex();
       if (Live[Index])
         continue;
       Live[Index] = true;
       setLastUse(VarIndex);
     }
   }
 }
 
@@ skipping 197 matching lines @@
         }
       }
       return;
     }
   }
   llvm_unreachable("Phi operand not found for specified target node");
 }
 
 // Change "a=phi(...)" to "a_phi=phi(...)" and return a new
 // instruction "a=a_phi".
-Inst *InstPhi::lower(Cfg *Func, CfgNode *Node) {
+Inst *InstPhi::lower(Cfg *Func) {
   Variable *Dest = getDest();
   assert(Dest);
   IceString PhiName = Dest->getName() + "_phi";
-  Variable *NewSrc = Func->makeVariable(Dest->getType(), Node, PhiName);
-  NewSrc->setIsMultidef();
+  Variable *NewSrc = Func->makeVariable(Dest->getType(), PhiName);
   this->Dest = NewSrc;
   InstAssign *NewInst = InstAssign::create(Func, Dest, NewSrc);
   // Set Dest and NewSrc to have affinity with each other, as a hint
   // for register allocation.
   Dest->setPreferredRegister(NewSrc, false);
   NewSrc->setPreferredRegister(Dest, false);
-  Dest->replaceDefinition(NewInst, Node);
   return NewInst;
 }
 
 InstRet::InstRet(Cfg *Func, Operand *RetValue)
     : Inst(Func, Ret, RetValue ? 1 : 0, NULL) {
   if (RetValue)
     addSource(RetValue);
 }
 
 InstSelect::InstSelect(Cfg *Func, Variable *Dest, Operand *Condition,
@@ skipping 389 matching lines @@
 
 void InstTarget::dump(const Cfg *Func) const {
   Ostream &Str = Func->getContext()->getStrDump();
   Str << "[TARGET] ";
   Inst::dump(Func);
 }
 
 void InstTarget::dumpExtras(const Cfg *Func) const { Inst::dumpExtras(Func); }
 
 } // end of namespace Ice