1 files changed, 85 insertions, 39 deletions

diff --git a/clang/lib/Analysis/ThreadSafetyCommon.cpp b/clang/lib/Analysis/ThreadSafetyCommon.cpp
index eae2552f051..cf9a7b8bf37 100644
--- a/clang/lib/Analysis/ThreadSafetyCommon.cpp
+++ b/clang/lib/Analysis/ThreadSafetyCommon.cpp
@@ -47,11 +47,12 @@ SExpr *getCanonicalVal(SExpr *E) {
       if (V->kind() != Variable::VK_Let)
         return V;
       D = V->definition();
-      if (auto *V2 = dyn_cast<Variable>(D)) {
+      auto *V2 = dyn_cast<Variable>(D);
+      if (V2)
         V = V2;
-        continue;
-      }
-    } while(false);
+      else
+        break;
+    } while (true);
 
     if (ThreadSafetyTIL::isTrivial(D))
       return D;
@@ -75,7 +76,7 @@ SExpr *getCanonicalVal(SExpr *E) {
 // canonical definition.  If so, mark the Phi node as redundant.
 // getCanonicalVal() will recursively call simplifyIncompletePhi().
 void simplifyIncompleteArg(Variable *V, til::Phi *Ph) {
-  assert(!Ph && Ph->status() == Phi::PH_Incomplete);
+  assert(Ph && Ph->status() == Phi::PH_Incomplete);
 
   // eliminate infinite recursion -- assume that this node is not redundant.
   Ph->setStatus(Phi::PH_MultiVal);
@@ -90,8 +91,21 @@ void simplifyIncompleteArg(Variable *V, til::Phi *Ph) {
     }
   }
   Ph->setStatus(Phi::PH_SingleVal);
+  // Eliminate Redundant Phi node.
+  V->setDefinition(Ph->values()[0]);
 }
 
+
+// Return true if E is a variable that points to an incomplete Phi node.
+inline bool isIncompleteVar(SExpr *E) {
+  if (Variable *V = dyn_cast<Variable>(E)) {
+    if (Phi *Ph = dyn_cast<Phi>(V->definition()))
+      return Ph->status() == Phi::PH_Incomplete;
+  }
+  return false;
+}
+
+
 }  // end namespace til
 
 
@@ -140,6 +154,7 @@ til::SExpr *SExprBuilder::translate(const Stmt *S, CallingContext *Ctx) {
   case Stmt::UnaryOperatorClass:
     return translateUnaryOperator(cast<UnaryOperator>(S), Ctx);
   case Stmt::BinaryOperatorClass:
+  case Stmt::CompoundAssignOperatorClass:
     return translateBinaryOperator(cast<BinaryOperator>(S), Ctx);
 
   case Stmt::ArraySubscriptExprClass:
@@ -277,6 +292,32 @@ til::SExpr *SExprBuilder::translateUnaryOperator(const UnaryOperator *UO,
 }
 
 
+til::SExpr *SExprBuilder::translateBinAssign(til::TIL_BinaryOpcode Op,
+                                             const BinaryOperator *BO,
+                                             CallingContext *Ctx) {
+  const Expr *LHS = BO->getLHS();
+  const Expr *RHS = BO->getRHS();
+  til::SExpr *E0 = translate(LHS, Ctx);
+  til::SExpr *E1 = translate(RHS, Ctx);
+
+  const ValueDecl *VD = nullptr;
+  til::SExpr *CV = nullptr;
+  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(LHS)) {
+    VD = DRE->getDecl();
+    CV = lookupVarDecl(VD);
+  }
+
+  if (Op != BO_Assign) {
+    til::SExpr *Arg = CV ? CV : new (Arena) til::Load(E0);
+    E1 = new (Arena) til::BinaryOp(Op, Arg, E1);
+    E1 = addStatement(E1, nullptr, VD);
+  }
+  if (VD && CV)
+    return updateVarDecl(VD, E1);
+  return new (Arena) til::Store(E0, E1);
+}
+
+
 til::SExpr *SExprBuilder::translateBinaryOperator(const BinaryOperator *BO,
                                                   CallingContext *Ctx) {
   switch (BO->getOpcode()) {
@@ -306,35 +347,24 @@ til::SExpr *SExprBuilder::translateBinaryOperator(const BinaryOperator *BO,
         til::BinaryOp(BO->getOpcode(), translate(BO->getLHS(), Ctx),
                       translate(BO->getRHS(), Ctx));
 
-  case BO_Assign: {
-    const Expr *LHS = BO->getLHS();
-    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(LHS)) {
-      const Expr *RHS = BO->getRHS();
-      til::SExpr *E1 = translate(RHS, Ctx);
-      return updateVarDecl(DRE->getDecl(), E1);
-    }
-    til::SExpr *E0 = translate(LHS, Ctx);
-    til::SExpr *E1 = translate(BO->getRHS(), Ctx);
-    return new (Arena) til::Store(E0, E1);
-  }
-  case BO_MulAssign:
-  case BO_DivAssign:
-  case BO_RemAssign:
-  case BO_AddAssign:
-  case BO_SubAssign:
-  case BO_ShlAssign:
-  case BO_ShrAssign:
-  case BO_AndAssign:
-  case BO_XorAssign:
-  case BO_OrAssign:
-    return new (Arena) til::Undefined(BO);
+  case BO_Assign:    return translateBinAssign(BO_Assign, BO, Ctx);
+  case BO_MulAssign: return translateBinAssign(BO_Mul, BO, Ctx);
+  case BO_DivAssign: return translateBinAssign(BO_Div, BO, Ctx);
+  case BO_RemAssign: return translateBinAssign(BO_Rem, BO, Ctx);
+  case BO_AddAssign: return translateBinAssign(BO_Add, BO, Ctx);
+  case BO_SubAssign: return translateBinAssign(BO_Sub, BO, Ctx);
+  case BO_ShlAssign: return translateBinAssign(BO_Shl, BO, Ctx);
+  case BO_ShrAssign: return translateBinAssign(BO_Shr, BO, Ctx);
+  case BO_AndAssign: return translateBinAssign(BO_And, BO, Ctx);
+  case BO_XorAssign: return translateBinAssign(BO_Xor, BO, Ctx);
+  case BO_OrAssign:  return translateBinAssign(BO_Or,  BO, Ctx);
 
   case BO_Comma:
-    // TODO: handle LHS
+    // The clang CFG should have already processed both sides.
     return translate(BO->getRHS(), Ctx);
-  }
 
   return new (Arena) til::Undefined(BO);
+  }
 }
 
 
@@ -495,14 +525,16 @@ void SExprBuilder::makePhiNodeVar(unsigned i, unsigned NPreds, til::SExpr *E) {
 
   // Make a new phi node: phi(..., E)
   // All phi args up to the current index are set to the current value.
+  til::SExpr *CurrE = CurrentLVarMap[i].second;
   til::Phi *Ph = new (Arena) til::Phi(Arena, NPreds);
   Ph->values().setValues(NPreds, nullptr);
   for (unsigned PIdx = 0; PIdx < ArgIndex; ++PIdx)
-    Ph->values()[PIdx] = CurrentLVarMap[i].second;
+    Ph->values()[PIdx] = CurrE;
   if (E)
     Ph->values()[ArgIndex] = E;
-  if (!E) {
-    // This is a non-minimal SSA node, which may be removed later.
+  // If E is from a back-edge, or either E or CurrE are incomplete, then
+  // mark this node as incomplete; we may need to remove it later.
+  if (!E || isIncompleteVar(E) || isIncompleteVar(CurrE)) {
     Ph->setStatus(til::Phi::PH_Incomplete);
   }
 
@@ -601,8 +633,7 @@ void SExprBuilder::mergePhiNodesBackEdge(const CFGBlock *Blk) {
 }
 
 
-
-void SExprBuilder::enterCFG(CFG *Cfg, const NamedDecl *D,
+void SExprBuilder::enterCFG(CFG *Cfg, const FunctionDecl *FD,
                             const CFGBlock *First) {
   // Perform initial setup operations.
   unsigned NBlocks = Cfg->getNumBlockIDs();
@@ -616,22 +647,35 @@ void SExprBuilder::enterCFG(CFG *Cfg, const NamedDecl *D,
     auto *BB = new (Arena) til::BasicBlock(Arena, 0, B->size());
     BlockMap[B->getBlockID()] = BB;
   }
-  CallCtx = new SExprBuilder::CallingContext(D);
+  CallCtx = new SExprBuilder::CallingContext(FD);
+
+  CurrentBB = lookupBlock(&Cfg->getEntry());
+  for (auto *Pm : FD->parameters()) {
+    QualType T = Pm->getType();
+    if (!T.isTrivialType(Pm->getASTContext()))
+      continue;
+
+    // Add parameters to local variable map.
+    // FIXME: right now we emulate params with loads; that should be fixed.
+    til::SExpr *Lp = new (Arena) til::LiteralPtr(Pm);
+    til::SExpr *Ld = new (Arena) til::Load(Lp);
+    til::SExpr *V  = addStatement(Ld, nullptr, Pm);
+    addVarDecl(Pm, V);
+  }
 }
 
 
 void SExprBuilder::enterCFGBlock(const CFGBlock *B) {
   // Intialize TIL basic block and add it to the CFG.
-  CurrentBB = BlockMap[B->getBlockID()];
+  CurrentBB = lookupBlock(B);
   CurrentBB->setNumPredecessors(B->pred_size());
   Scfg->add(CurrentBB);
 
   CurrentBlockInfo = &BBInfo[B->getBlockID()];
-  CurrentArguments.clear();
-  CurrentInstructions.clear();
 
   // CurrentLVarMap is moved to ExitMap on block exit.
-  assert(!CurrentLVarMap.valid() && "CurrentLVarMap already initialized.");
+  // FIXME: the entry block will hold function parameters.
+  // assert(!CurrentLVarMap.valid() && "CurrentLVarMap already initialized.");
 }
 
 
@@ -721,6 +765,8 @@ void SExprBuilder::handleSuccessorBackEdge(const CFGBlock *Succ) {
 
 
 void SExprBuilder::exitCFGBlock(const CFGBlock *B) {
+  CurrentArguments.clear();
+  CurrentInstructions.clear();
   CurrentBlockInfo->ExitMap = std::move(CurrentLVarMap);
   CurrentBB = nullptr;
   CurrentBlockInfo = nullptr;