[PATCH 0/2] Implement two new Ada attributes

[PATCH 0/2] Implement two new Ada attributes

[Tom Tromey]

This short series starts with a small cleanup, then implements two new
attributes from Ada 2022.

---
Tom Tromey (2):
      Remove ada_attribute_name
      Implement 'Enum_Val and 'Enum_Rep

 gdb/NEWS                                    |  2 +
 gdb/ada-exp.h                               | 34 ++++++++--
 gdb/ada-exp.y                               | 14 +++-
 gdb/ada-lang.c                              | 99 +++++++++++++++++------------
 gdb/ada-lex.l                               |  2 +
 gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp |  5 ++
 6 files changed, 108 insertions(+), 48 deletions(-)
---
base-commit: 3169b734cf07ec8800436b2c5298897aa993d2be
change-id: 20230629-enum-attrs-2a908f1e5ba0

Best regards,
-- 
Tom Tromey <tromey@adacore.com>

[PATCH 1/2] Remove ada_attribute_name

[Tom Tromey]

ada_attribute_name uses an array that must be kept in sync with an
enum -- but the comment here refers to an enum that no longer exists.
Looking at the sole caller, I see this can only be called for two
opcodes.  So, remove this entirely and inline it.
---
 gdb/ada-lang.c | 41 +++++++++--------------------------------
 1 file changed, 9 insertions(+), 32 deletions(-)

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 8e506bd4f2b..3d629cc110f 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -8767,35 +8767,6 @@ ada_to_fixed_value (struct value *val)
 
 /* Attributes */
 
-/* Table mapping attribute numbers to names.
-   NOTE: Keep up to date with enum ada_attribute definition in ada-lang.h.  */
-
-static const char * const attribute_names[] = {
-  "<?>",
-
-  "first",
-  "last",
-  "length",
-  "image",
-  "max",
-  "min",
-  "modulus",
-  "pos",
-  "size",
-  "tag",
-  "val",
-  0
-};
-
-static const char *
-ada_attribute_name (enum exp_opcode n)
-{
-  if (n >= OP_ATR_FIRST && n <= (int) OP_ATR_VAL)
-    return attribute_names[n - OP_ATR_FIRST + 1];
-  else
-    return attribute_names[0];
-}
-
 /* Evaluate the 'POS attribute applied to ARG.  */
 
 static LONGEST
@@ -10271,6 +10242,12 @@ static value *
 ada_unop_atr (struct expression *exp, enum noside noside, enum exp_opcode op,
 	      struct value *arg1, struct type *type_arg, int tem)
 {
+  const char *attr_name = nullptr;
+  if (op == OP_ATR_FIRST)
+    attr_name = "first";
+  else if (op == OP_ATR_LAST)
+    attr_name = "last";
+
   if (noside == EVAL_AVOID_SIDE_EFFECTS)
     {
       if (type_arg == NULL)
@@ -10288,7 +10265,7 @@ ada_unop_atr (struct expression *exp, enum noside noside, enum exp_opcode op,
 	    case OP_ATR_FIRST:
 	    case OP_ATR_LAST:
 	      type_arg = ada_index_type (type_arg, tem,
-					 ada_attribute_name (op));
+					 attr_name);
 	      break;
 	    case OP_ATR_LENGTH:
 	      type_arg = builtin_type (exp->gdbarch)->builtin_int;
@@ -10311,7 +10288,7 @@ ada_unop_atr (struct expression *exp, enum noside noside, enum exp_opcode op,
       else
 	{
 	  type = ada_index_type (arg1->type (), tem,
-				 ada_attribute_name (op));
+				 attr_name);
 	  if (type == NULL)
 	    type = builtin_type (exp->gdbarch)->builtin_int;
 	}
@@ -10369,7 +10346,7 @@ ada_unop_atr (struct expression *exp, enum noside noside, enum exp_opcode op,
 	type = builtin_type (exp->gdbarch)->builtin_int;
       else
 	{
-	  type = ada_index_type (type_arg, tem, ada_attribute_name (op));
+	  type = ada_index_type (type_arg, tem, attr_name);
 	  if (type == NULL)
 	    type = builtin_type (exp->gdbarch)->builtin_int;
 	}

-- 
2.40.1

[PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Tom Tromey]

This patch implements the Ada 2022 attributes 'Enum_Val and 'Enum_Rep.
---
 gdb/NEWS                                    |  2 +
 gdb/ada-exp.h                               | 34 ++++++++++++++---
 gdb/ada-exp.y                               | 14 ++++++-
 gdb/ada-lang.c                              | 58 ++++++++++++++++++++++++-----
 gdb/ada-lex.l                               |  2 +
 gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp |  5 +++
 6 files changed, 99 insertions(+), 16 deletions(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index fd42864c692..5b56a86da6f 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -78,6 +78,8 @@
   functionality is also available for dprintf when dprintf-style is
   'gdb'.
 
+* The Ada 2022 'Enum_Rep and 'Enum_Val attributes are now supported.
+
 * New commands
 
 maintenance print record-instruction [ N ]
diff --git a/gdb/ada-exp.h b/gdb/ada-exp.h
index 54ae4529def..dc34a43bdd6 100644
--- a/gdb/ada-exp.h
+++ b/gdb/ada-exp.h
@@ -69,7 +69,14 @@ extern struct value *ada_pos_atr (struct type *expect_type,
 				  struct expression *exp,
 				  enum noside noside, enum exp_opcode op,
 				  struct value *arg);
-extern struct value *ada_val_atr (enum noside noside, struct type *type,
+extern struct value *ada_atr_enum_rep (struct expression *exp,
+				       enum noside noside, struct type *type,
+				       struct value *arg);
+extern struct value *ada_atr_enum_val (struct expression *exp,
+				       enum noside noside, struct type *type,
+				       struct value *arg);
+extern struct value *ada_val_atr (struct expression *exp,
+				  enum noside noside, struct type *type,
 				  struct value *arg);
 extern struct value *ada_binop_exp (struct type *expect_type,
 				    struct expression *exp,
@@ -424,8 +431,14 @@ class ada_var_msym_value_operation
   using operation::do_generate_ax;
 };
 
-/* Implement the Ada 'val attribute.  */
-class ada_atr_val_operation
+typedef struct value *ada_atr_ftype (struct expression *exp,
+				     enum noside noside,
+				     struct type *type,
+				     struct value *arg);
+
+/* Implement several Ada attributes.  */
+template<ada_atr_ftype FUNC>
+class ada_atr_operation
   : public tuple_holding_operation<struct type *, operation_up>
 {
 public:
@@ -434,12 +447,23 @@ class ada_atr_val_operation
 
   value *evaluate (struct type *expect_type,
 		   struct expression *exp,
-		   enum noside noside) override;
+		   enum noside noside) override
+  {
+    value *arg = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
+    return FUNC (exp, noside, std::get<0> (m_storage), arg);
+  }
 
   enum exp_opcode opcode () const override
-  { return OP_ATR_VAL; }
+  {
+    /* The value here generally doesn't matter.  */
+    return OP_ATR_VAL;
+  }
 };
 
+using ada_atr_val_operation = ada_atr_operation<ada_val_atr>;
+using ada_atr_enum_rep_operation = ada_atr_operation<ada_atr_enum_rep>;
+using ada_atr_enum_val_operation = ada_atr_operation<ada_atr_enum_val>;
+
 /* The indirection operator for Ada.  */
 class ada_unop_ind_operation
   : public unop_ind_base_operation
diff --git a/gdb/ada-exp.y b/gdb/ada-exp.y
index 23aebf0e236..019ac85211e 100644
--- a/gdb/ada-exp.y
+++ b/gdb/ada-exp.y
@@ -474,7 +474,7 @@ make_tick_completer (struct stoken tok)
 %right TICK_ACCESS TICK_ADDRESS TICK_FIRST TICK_LAST TICK_LENGTH
 %right TICK_MAX TICK_MIN TICK_MODULUS
 %right TICK_POS TICK_RANGE TICK_SIZE TICK_TAG TICK_VAL
-%right TICK_COMPLETE
+%right TICK_COMPLETE TICK_ENUM_REP TICK_ENUM_VAL
  /* The following are right-associative only so that reductions at this
     precedence have lower precedence than '.' and '('.  The syntax still
     forces a.b.c, e.g., to be LEFT-associated.  */
@@ -864,6 +864,18 @@ primary :	primary TICK_ACCESS
 			  pstate->push_new<ada_atr_val_operation>
 			    ($1, std::move (arg));
 			}
+	|	type_prefix TICK_ENUM_REP '(' exp ')'
+			{
+			  operation_up arg = ada_pop (true, $1);
+			  pstate->push_new<ada_atr_enum_rep_operation>
+			    ($1, std::move (arg));
+			}
+	|	type_prefix TICK_ENUM_VAL '(' exp ')'
+			{
+			  operation_up arg = ada_pop (true, $1);
+			  pstate->push_new<ada_atr_enum_val_operation>
+			    ($1, std::move (arg));
+			}
 	|	type_prefix TICK_MODULUS
 			{
 			  struct type *type_arg = check_typedef ($1);
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 3d629cc110f..795207589d0 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -8815,7 +8815,8 @@ val_atr (struct type *type, LONGEST val)
 }
 
 struct value *
-ada_val_atr (enum noside noside, struct type *type, struct value *arg)
+ada_val_atr (struct expression *exp, enum noside noside, struct type *type,
+	     struct value *arg)
 {
   if (noside == EVAL_AVOID_SIDE_EFFECTS)
     return value::zero (type, not_lval);
@@ -8827,6 +8828,52 @@ ada_val_atr (enum noside noside, struct type *type, struct value *arg)
 
   return val_atr (type, value_as_long (arg));
 }
+
+/* Implementation of the enum_rep attribute.  */
+struct value *
+ada_atr_enum_rep (struct expression *exp, enum noside noside, struct type *type,
+		  struct value *arg)
+{
+  struct type *inttype = builtin_type (exp->gdbarch)->builtin_int;
+  if (noside == EVAL_AVOID_SIDE_EFFECTS)
+    return value::zero (inttype, not_lval);
+
+  if (type->code () == TYPE_CODE_RANGE)
+    type = type->target_type ();
+  if (type->code () != TYPE_CODE_ENUM)
+    error (_("'Enum_Rep only defined on enum types"));
+  if (!types_equal (type, arg->type ()))
+    error (_("'Enum_Rep requires argument to have same type as enum"));
+
+  return value_cast (inttype, arg);
+}
+
+/* Implementation of the enum_val attribute.  */
+struct value *
+ada_atr_enum_val (struct expression *exp, enum noside noside, struct type *type,
+		  struct value *arg)
+{
+  struct type *original_type = type;
+  if (noside == EVAL_AVOID_SIDE_EFFECTS)
+    return value::zero (original_type, not_lval);
+
+  if (type->code () == TYPE_CODE_RANGE)
+    type = type->target_type ();
+  if (type->code () != TYPE_CODE_ENUM)
+    error (_("'Enum_Val only defined on enum types"));
+  if (!integer_type_p (arg->type ()))
+    error (_("'Enum_Val requires integral argument"));
+
+  LONGEST value = value_as_long (arg);
+  for (int i = 0; i < type->num_fields (); ++i)
+    {
+      if (type->field (i).loc_enumval () == value)
+	return value_from_longest (original_type, value);
+    }
+
+  error (_("value %s not found in enum"), plongest (value));
+}
+
 \f
 
 				/* Evaluation */
@@ -10919,15 +10966,6 @@ ada_var_value_operation::do_generate_ax (struct expression *exp,
   var_value_operation::do_generate_ax (exp, ax, value, cast_type);
 }
 
-value *
-ada_atr_val_operation::evaluate (struct type *expect_type,
-				 struct expression *exp,
-				 enum noside noside)
-{
-  value *arg = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
-  return ada_val_atr (noside, std::get<0> (m_storage), arg);
-}
-
 value *
 ada_unop_ind_operation::evaluate (struct type *expect_type,
 				  struct expression *exp,
diff --git a/gdb/ada-lex.l b/gdb/ada-lex.l
index 8c0e7679832..0547b704eaf 100644
--- a/gdb/ada-lex.l
+++ b/gdb/ada-lex.l
@@ -684,6 +684,8 @@ attributes[] = {
   { "size", TICK_SIZE },
   { "tag", TICK_TAG },
   { "val", TICK_VAL },
+  { "enum_rep", TICK_ENUM_REP },
+  { "enum_val", TICK_ENUM_VAL },
 };
 
 /* Return the syntactic code corresponding to the attribute name or
diff --git a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp
index 502a5ab5fd9..397189487bb 100644
--- a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp
+++ b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp
@@ -61,3 +61,8 @@ gdb_test "print enum_subrange'val(3)" " = lit3"
 
 gdb_test "print indexed_by_enum(lit2)" "43"
 gdb_test "print s(2)" "101 'e'"
+
+gdb_test "print enum_with_gaps'enum_rep(lit3)" " = 13" \
+    "enum_rep"
+gdb_test "print enum_with_gaps'enum_val(21)" " = lit4" \
+    "enum_val"

-- 
2.40.1

Re: [PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Eli Zaretskii]

> Date: Thu, 29 Jun 2023 13:44:31 -0600
> From: Tom Tromey via Gdb-patches <gdb-patches@sourceware.org>
> 
> This patch implements the Ada 2022 attributes 'Enum_Val and 'Enum_Rep.
> ---
>  gdb/NEWS                                    |  2 +
>  gdb/ada-exp.h                               | 34 ++++++++++++++---
>  gdb/ada-exp.y                               | 14 ++++++-
>  gdb/ada-lang.c                              | 58 ++++++++++++++++++++++++-----
>  gdb/ada-lex.l                               |  2 +
>  gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp |  5 +++
>  6 files changed, 99 insertions(+), 16 deletions(-)
> 
> diff --git a/gdb/NEWS b/gdb/NEWS
> index fd42864c692..5b56a86da6f 100644
> --- a/gdb/NEWS
> +++ b/gdb/NEWS
> @@ -78,6 +78,8 @@
>    functionality is also available for dprintf when dprintf-style is
>    'gdb'.
>  
> +* The Ada 2022 'Enum_Rep and 'Enum_Val attributes are now supported.
> +
>  * New commands

The NEWS part is OK, but why the weird apostrophe "quoting"?  Is it
needed?

Thanks.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>

Re: [PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Tom Tromey]

>>>>> "Eli" == Eli Zaretskii <eliz@gnu.org> writes:

>> +* The Ada 2022 'Enum_Rep and 'Enum_Val attributes are now supported.

Eli> The NEWS part is OK, but why the weird apostrophe "quoting"?  Is it
Eli> needed?

I think that is how Ada normally refers to attributes.
They are like suffixes on an expression where the ' is the separator.

Tom

Re: [PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Eli Zaretskii]

> From: Tom Tromey <tromey@adacore.com>
> Cc: Tom Tromey <tromey@adacore.com>,  gdb-patches@sourceware.org
> Date: Fri, 30 Jun 2023 11:39:26 -0600
> 
> >>>>> "Eli" == Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> +* The Ada 2022 'Enum_Rep and 'Enum_Val attributes are now supported.
> 
> Eli> The NEWS part is OK, but why the weird apostrophe "quoting"?  Is it
> Eli> needed?
> 
> I think that is how Ada normally refers to attributes.
> They are like suffixes on an expression where the ' is the separator.

But NEWS is not Ada sources, it's a piece of GNU documentation.  If
those are symbols, I think they should be quoted 'like this'.

Re: [PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Tom Tromey]

Eli> But NEWS is not Ada sources, it's a piece of GNU documentation.  If
Eli> those are symbols, I think they should be quoted 'like this'.

In this context these are not quotes but rather apostrophes used to mark
the start of an attribute.

I can remove them.  I would rather not use them as quotes here.  That
would read strangely.

Tom

Re: [PATCH 2/2] Implement 'Enum_Val and 'Enum_Rep

[Eli Zaretskii]

> From: Tom Tromey <tromey@adacore.com>
> Cc: Tom Tromey <tromey@adacore.com>,  gdb-patches@sourceware.org
> Date: Fri, 30 Jun 2023 13:59:10 -0600
> 
> Eli> But NEWS is not Ada sources, it's a piece of GNU documentation.  If
> Eli> those are symbols, I think they should be quoted 'like this'.
> 
> In this context these are not quotes but rather apostrophes used to mark
> the start of an attribute.
> 
> I can remove them.  I would rather not use them as quotes here.  That
> would read strangely.

To me the text with the apostrophes reads strangely.  But I won't
argue; if you feel the apostrophes make the text better, I'm okay with
that.

Thanks.

Re: [PATCH 0/2] Implement two new Ada attributes

[Tom Tromey]

>>>>> "Tom" == Tom Tromey via Gdb-patches <gdb-patches@sourceware.org> writes:

Tom> This short series starts with a small cleanup, then implements two new
Tom> attributes from Ada 2022.

I'm checking these in.

Tom