[flang-commits] [flang] [flang] Add parser support for explicit-shape-bounds-spec (PR #188447)

[Eugene Epshteyn via flang-commits]

================
@@ -237,15 +238,79 @@ ArraySpec ArraySpecAnalyzer::Analyze(const parser::ComponentArraySpec &x) {
   CHECK(!arraySpec_.empty());
   return arraySpec_;
 }
+
+static bool shouldRewriteShapeSpecListToExplicitBounds(
+    SemanticsContext &context, const parser::ArraySpec &x) {
+  auto &explicitShapeSpecList{std::get<std::list<parser::ExplicitShapeSpec>>(
+      const_cast<parser::ArraySpec&>(x).u)};
+  
+  if (explicitShapeSpecList.size() != 1) {
+    return false;
+  }
+
+  auto &explicitShapeSpec{explicitShapeSpecList.front()};
+  const auto &upperBound{std::get<1>(explicitShapeSpec.t)};
+  const auto &lowerBoundOpt{std::get<0>(explicitShapeSpec.t)};
+  
+  bool foundArray{false};
+  
+  if (MaybeExpr analyzedExpr = AnalyzeExpr(context, upperBound.v.thing.thing.value());
+      analyzedExpr && (analyzedExpr->Rank() > 0)) {
+    foundArray = true;
+  }
+  
+  if (lowerBoundOpt) {
+    const auto &lowerBound{*lowerBoundOpt};
+    if (MaybeExpr analyzedExpr = AnalyzeExpr(context, lowerBound.v.thing.thing.value());
+        analyzedExpr && (analyzedExpr->Rank() > 0)) {
+      foundArray = true;
+    }
+  }
+  
+  return foundArray;
+}
+
+static void rewriteShapeSpecListToExplicitBounds(const parser::ArraySpec &x) {
+  auto &explicitShapeSpecList{std::get<std::list<parser::ExplicitShapeSpec>>(
+      const_cast<parser::ArraySpec&>(x).u)};
+  auto &mutableArraySpec{const_cast<parser::ArraySpec&>(x)};
+  auto &mutableExplicitShapeSpec{explicitShapeSpecList.front()};
+  
+  auto &mutableUpperBound{std::get<1>(mutableExplicitShapeSpec.t)};
+  parser::IntExpr upperIntExpr{std::move(mutableUpperBound.v.thing)};
+
+  auto &lowerBoundOpt{std::get<0>(mutableExplicitShapeSpec.t)};
+  std::optional<parser::IntExpr> lowerIntExpr;
+  if (lowerBoundOpt) {
+    auto &mutableLowerBound{std::get<0>(mutableExplicitShapeSpec.t)};
----------------
eugeneepshteyn wrote:

Aren't `lowerBoundOpt` and `mutableLowerBound` the same?  They both do `std::get<0>(mutableExplicitShapeSpec.t)`

https://github.com/llvm/llvm-project/pull/188447