Introduce ada_string_operation

This adds class ada_string_operation, which implements string
constants for Ada.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* ada-lang.c (ada_string_operation::evaluate): New method.
	* ada-exp.h (class ada_string_operation): New.

3 files changed, 31 insertions, 0 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index ff5862e..816f5a8 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,10 @@
 2021-03-08  Tom Tromey  <tom@tromey.com>
 
+	* ada-lang.c (ada_string_operation::evaluate): New method.
+	* ada-exp.h (class ada_string_operation): New.
+
+2021-03-08  Tom Tromey  <tom@tromey.com>
+
 	* ada-lang.c (ada_wrapped_operation::evaluate): New method.
 	* ada-exp.h: New file.
 
diff --git a/gdb/ada-exp.h b/gdb/ada-exp.h
index 3f780dc..88ed0c5 100644
--- a/gdb/ada-exp.h
+++ b/gdb/ada-exp.h
@@ -42,6 +42,19 @@ public:
   { return std::get<0> (m_storage)->opcode (); }
 };
 
+/* An Ada string constant.  */
+class ada_string_operation
+  : public string_operation
+{
+public:
+
+  using string_operation::string_operation;
+
+  value *evaluate (struct type *expect_type,
+		   struct expression *exp,
+		   enum noside noside) override;
+};
+
 } /* namespace expr */
 
 #endif /* ADA_EXP_H */
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 4db5823..0666302 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -10414,6 +10414,19 @@ ada_wrapped_operation::evaluate (struct type *expect_type,
   return result;
 }
 
+value *
+ada_string_operation::evaluate (struct type *expect_type,
+				struct expression *exp,
+				enum noside noside)
+{
+  value *result = string_operation::evaluate (expect_type, exp, noside);
+  /* The result type will have code OP_STRING, bashed there from 
+     OP_ARRAY.  Bash it back.  */
+  if (value_type (result)->code () == TYPE_CODE_STRING)
+    value_type (result)->set_code (TYPE_CODE_ARRAY);
+  return result;
+}
+
 }
 
 /* Implement the evaluate_exp routine in the exp_descriptor structure