[flang] Fix the vector version of EOSHIFT with a BOUNDARY argument

[PeteSteinfeld]

Summary

When the vector version of EOSHIFT was called, the BOUNDARY argument was being
ignored. I fixed that and added a test that would not pass without this fix.

flang/runtime/transformational.cpp

void RTNAME(EoshiftVector)(Descriptor &result, const Descriptor &source,
   if (!boundary) {
     DefaultInitialize(result, terminator);
   }
   SubscriptValue lb{source.GetDimension(0).LowerBound()};
   for (SubscriptValue j{1}; j <= extent; ++j) {
     SubscriptValue sourceAt{lb + j - 1 + shift};
     if (sourceAt >= lb && sourceAt < lb + extent) {
       CopyElement(result, &j, source, &sourceAt, terminator);
+    } else if (boundary) {
+      CopyElement(result, &j, *boundary, 0, terminator);
     }
   }
 }
 
 // PACK
 void RTNAME(Pack)(Descriptor &result, const Descriptor &source,
     const Descriptor &mask, const Descriptor *vector, const char *sourceFile,
     int line) {

flang/unittests/Runtime/Transformational.cpp

TEST(Transformational, Shifts) {
   EXPECT_EQ(result.GetDimension(1).Extent(), 3);
   EXPECT_EQ(result.type(), (TypeCode{TypeCategory::Integer, 4}));
   static std::int32_t eoshiftExpect1[6]{2, -1, -2, 3, -3, -3};
   for (int j{0}; j < 6; ++j) {
     EXPECT_EQ(
         *result.ZeroBasedIndexedElement<std::int32_t>(j), eoshiftExpect1[j]);
   }
   result.Destroy();
+
+  // VECTOR EOSHIFT
+  StaticDescriptor<0> boundaryDescriptor;
+  Descriptor vectorBoundary{boundaryDescriptor.descriptor()};
+  std::int32_t boundaryValue{343};
+  vectorBoundary.Establish(TypeCategory::Integer, 4,
+      const_cast<void *>(reinterpret_cast<const void *>(&boundaryValue)), 0);
+  RTNAME(EoshiftVector)
+  (vectorResult, *vector, 2, &vectorBoundary, __FILE__, __LINE__);
+  EXPECT_EQ(vectorResult.type(), array->type());
+  EXPECT_EQ(vectorResult.rank(), 1);
+  EXPECT_EQ(vectorResult.GetDimension(0).LowerBound(), 1);
+  EXPECT_EQ(vectorResult.GetDimension(0).Extent(), 6);
+  EXPECT_EQ(vectorResult.type(), (TypeCode{TypeCategory::Integer, 4}));
+  static std::int32_t eoshiftVectorExpect[6]{3, 4, 5, 6, 343, 343};
+  for (int j{0}; j < 6; ++j) {
+    EXPECT_EQ(*vectorResult.ZeroBasedIndexedElement<std::int32_t>(j),
+        eoshiftVectorExpect[j]);
+  }
+  vectorResult.Destroy();
 }
 
 TEST(Transformational, Pack) {
   // ARRAY  1 3 5
   //        2 4 6
   auto array{MakeArray<TypeCategory::Integer, 4>(
       std::vector<int>{2, 3}, std::vector<std::int32_t>{1, 2, 3, 4, 5, 6})};
   array->GetDimension(0).SetLowerBound(2); // shouldn't matter