Fix bugs in 'val and 'pos with range types

In Ada, the 'val and 'pos attributes can be used to map from an
enumeration constant to its position in the enum and vice versa.
These operators did not work properly when the type in question was a
subrange of an enum type with "holes".

gdb/ChangeLog
2020-05-26  Tom Tromey  <tromey@adacore.com>

	* ada-lang.c (value_val_atr): Handle TYPE_CODE_RANGE.
	* gdbtypes.c (discrete_position): Handle TYPE_CODE_RANGE.

gdb/testsuite/ChangeLog
2020-05-26  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/arr_acc_idx_w_gap.exp: Add enum subrange tests.
	* gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads (Enum_Subrange): New
	type.
	* gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb (V): New
	variable.

7 files changed, 28 insertions, 2 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2e21613..00d36ab 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-05-26  Tom Tromey  <tromey@adacore.com>
+
+	* ada-lang.c (value_val_atr): Handle TYPE_CODE_RANGE.
+	* gdbtypes.c (discrete_position): Handle TYPE_CODE_RANGE.
+
 2020-05-25  Cristiano De Alti  <cristiano_dealti@hotmail.com>
 
 	PR gdb/13519
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 7522917..5ffb2d6 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -9148,6 +9148,9 @@ value_val_atr (struct type *type, struct value *arg)
   if (!integer_type_p (value_type (arg)))
     error (_("'VAL requires integral argument"));
 
+  if (type->code () == TYPE_CODE_RANGE)
+    type = TYPE_TARGET_TYPE (type);
+
   if (type->code () == TYPE_CODE_ENUM)
     {
       long pos = value_as_long (arg);
diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c
index 4fe8d9a..2ee6989 100644
--- a/gdb/gdbtypes.c
+++ b/gdb/gdbtypes.c
@@ -1155,6 +1155,9 @@ get_array_bounds (struct type *type, LONGEST *low_bound, LONGEST *high_bound)
 int
 discrete_position (struct type *type, LONGEST val, LONGEST *pos)
 {
+  if (type->code () == TYPE_CODE_RANGE)
+    type = TYPE_TARGET_TYPE (type);
+
   if (type->code () == TYPE_CODE_ENUM)
     {
       int i;
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 50473fc..0cc377f 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2020-05-26  Tom Tromey  <tromey@adacore.com>
+
+	* gdb.ada/arr_acc_idx_w_gap.exp: Add enum subrange tests.
+	* gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads (Enum_Subrange): New
+	type.
+	* gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb (V): New
+	variable.
+
 2020-05-26  Christian Biesinger  <cbiesinger@google.com>
 
 	* Makefile.in: Use = instead of == for the test command
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 fd7ac44..c08070e 100644
--- a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp
+++ b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap.exp
@@ -53,3 +53,7 @@ gdb_test "print indexed_by_enum(lit2..lit4)" \
          " = \\(lit2 => 43, 42, 41\\)"
 gdb_test "print s(2..4)" \
          " = \"ell\""
+
+gdb_test "print v" " = lit3"
+gdb_test "print enum_subrange'pos(v)" " = 3"
+gdb_test "print enum_subrange'val(3)" " = lit3"
diff --git a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads
index 6e073e8..7193800 100644
--- a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads
+++ b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap.ads
@@ -34,14 +34,16 @@ package Enum_With_Gap is
      );
    for Enum_With_Gaps'size use 16;
 
+   type Enum_Subrange is new Enum_With_Gaps range Lit1 .. Lit3;
+
    type MyWord is range 0 .. 16#FFFF# ;
    for MyWord'Size use 16;
 
    type AR is array (Enum_With_Gaps range <>) of MyWord;
    type AR_Access is access AR;
-   
+
    type String_Access is access String;
-   
+
    procedure Do_Nothing (E : AR_Access);
    procedure Do_Nothing (E : String_Access);
 
diff --git a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb
index da37dd7..752b883 100644
--- a/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb
+++ b/gdb/testsuite/gdb.ada/arr_acc_idx_w_gap/enum_with_gap_main.adb
@@ -19,6 +19,7 @@ procedure Enum_With_Gap_Main is
    Indexed_By_Enum : AR_Access :=
      new AR'(LIT1 => 1,  LIT2 => 43, LIT3 => 42, LIT4 => 41);
    S : String_Access := new String'("Hello!");
+   V : Enum_Subrange := LIT3;
 begin
    Do_Nothing (Indexed_By_Enum); --  BREAK
    Do_Nothing (S);