[flang] Remove needless "anyIntrinsicDefinedOps", fixing iterative ex…

…pr analysis

The flag "anyIntrinsicDefinedOps" is always set nowadays, as there are intrinsic
modules that define operator(==) and (!=).  This disables the iterative
expression analysis mechanism, also unnecessarily, and it is possible to
overflow the stack when analyzing very deep expression trees like the ones
that show up in artificial stress tests.  Remove the flag.

Differential Revision: https://reviews.llvm.org/D159022

flang/include/flang/Semantics/semantics.h

@@ -144,14 +144,6 @@ class SemanticsContext {
     return *this;
   }
 
-  bool anyDefinedIntrinsicOperator() const {
-    return anyDefinedIntrinsicOperator_;
-  }
-  SemanticsContext &set_anyDefinedIntrinsicOperator(bool yes = true) {
-    anyDefinedIntrinsicOperator_ = yes;
-    return *this;
-  }
-
   const DeclTypeSpec &MakeNumericType(TypeCategory, int kind = 0);
   const DeclTypeSpec &MakeLogicalType(int kind = 0);
 
@@ -286,7 +278,6 @@ class SemanticsContext {
   const Scope *ppcBuiltinsScope_{nullptr}; // module __ppc_intrinsics
   std::list<parser::Program> modFileParseTrees_;
   std::unique_ptr<CommonBlockMap> commonBlockMap_;
-  bool anyDefinedIntrinsicOperator_{false};
 };
 
 class Semantics {

flang/lib/Semantics/expression.cpp

@@ -3584,7 +3584,7 @@ MaybeExpr ExpressionAnalyzer::Analyze(const parser::Expr &expr) {
     if (expr.typedExpr) {
       return expr.typedExpr->v;
     }
-    if (!wasIterativelyAnalyzing && !context_.anyDefinedIntrinsicOperator()) {
+    if (!wasIterativelyAnalyzing) {
       iterativelyAnalyzingSubexpressions_ = true;
       result = IterativelyAnalyzeSubexpressions(expr);
     }

flang/lib/Semantics/resolve-names.cpp

@@ -3269,11 +3269,6 @@ bool InterfaceVisitor::Pre(const parser::GenericSpec &x) {
   if (auto *symbol{FindInScope(GenericSpecInfo{x}.symbolName())}) {
     SetGenericSymbol(*symbol);
   }
-  if (const auto *opr{std::get_if<parser::DefinedOperator>(&x.u)}; opr &&
-      std::holds_alternative<parser::DefinedOperator::IntrinsicOperator>(
-          opr->u)) {
-    context().set_anyDefinedIntrinsicOperator(true);
-  }
   return false;
 }