Fix issues with the conditional discard workarounds to do with assignments.

src/compiler/Intermediate.cpp

@@ -804,9 +804,7 @@ bool TIntermSelection::replaceChildNode(
 //
 // Say whether or not an operation node changes the value of a variable.
 //
-// Returns true if state is modified.
-//
-bool TIntermOperator::hasSideEffects() const
+bool TIntermOperator::isAssignment() const
 {
     switch (op) {
         case EOpPostIncrement:

src/compiler/ValidateLimitations.cpp

@@ -457,7 +457,7 @@ bool ValidateLimitations::validateFunctionCall(TIntermAggregate* node)
 bool ValidateLimitations::validateOperation(TIntermOperator* node,
                                             TIntermNode* operand) {
     // Check if loop index is modified in the loop body.
-    if (!withinLoopBody() || !node->hasSideEffects())
+    if (!withinLoopBody() || !node->isAssignment())
         return true;
 
     const TIntermSymbol* symbol = operand->getAsSymbolNode();

src/compiler/depgraph/DependencyGraphBuilder.cpp

@@ -94,7 +94,7 @@ void TDependencyGraphBuilder::visitSymbol(TIntermSymbol* intermSymbol)
 bool TDependencyGraphBuilder::visitBinary(Visit visit, TIntermBinary* intermBinary)
 {
     TOperator op = intermBinary->getOp();
-    if (op == EOpInitialize || intermBinary->hasSideEffects())
+    if (op == EOpInitialize || intermBinary->isAssignment())
         visitAssignment(intermBinary);
     else if (op == EOpLogicalAnd || op == EOpLogicalOr)
         visitLogicalOp(intermBinary);

src/compiler/intermediate.h

@@ -406,9 +406,11 @@ public:
     TOperator getOp() const { return op; }
     void setOp(TOperator o) { op = o; }
 
-    virtual bool hasSideEffects() const;
+    bool isAssignment() const;
     bool isConstructor() const;
 
+    virtual bool hasSideEffects() const { return isAssignment(); }
+
 protected:
     TIntermOperator(TOperator o) : TIntermTyped(TType(EbtFloat, EbpUndefined)), op(o) {}
     TIntermOperator(TOperator o, TType& t) : TIntermTyped(t), op(o) {}   
@@ -427,7 +429,7 @@ public:
     virtual bool replaceChildNode(
         TIntermNode *original, TIntermNode *replacement);
 
-    virtual bool hasSideEffects() const { return (TIntermOperator::hasSideEffects() || left->hasSideEffects() || right->hasSideEffects()); }
+    virtual bool hasSideEffects() const { return (isAssignment() || left->hasSideEffects() || right->hasSideEffects()); }
 
     void setLeft(TIntermTyped* n) { left = n; }
     void setRight(TIntermTyped* n) { right = n; }
@@ -459,7 +461,7 @@ public:
     virtual bool replaceChildNode(
         TIntermNode *original, TIntermNode *replacement);
 
-    virtual bool hasSideEffects() const { return (TIntermOperator::hasSideEffects() || operand->hasSideEffects()); }
+    virtual bool hasSideEffects() const { return (isAssignment() || operand->hasSideEffects()); }
 
     void setOperand(TIntermTyped* o) { operand = o; }
     TIntermTyped* getOperand() { return operand; }