Mirror of the gdb-patches mailing list
 help / color / mirror / Atom feed
From: Tom Tromey <tromey@adacore.com>
To: gdb-patches@sourceware.org
Cc: Tom Tromey <tromey@adacore.com>
Subject: [PATCH 8/9] Use bit stride when taking slice of array
Date: Wed, 30 Sep 2020 14:05:59 -0600	[thread overview]
Message-ID: <20200930200600.1207702-9-tromey@adacore.com> (raw)
In-Reply-To: <20200930200600.1207702-1-tromey@adacore.com>

Testing with -fgnat-encodings=minimal showed that the Ada code failed
to use the bit stride of an array when taking a slice.  This patch
fixes the oversight.

2020-09-30  Tom Tromey  <tromey@adacore.com>

	* ada-lang.c (ada_value_slice_from_ptr): Use bit size.

gdb/testsuite/ChangeLog
2020-09-30  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/array_of_variant.exp: New file.
	* gdb.ada/array_of_variant/p.adb: New file.
	* gdb.ada/array_of_variant/pck.ads: New file.
	* gdb.ada/array_of_variant/pck.adb: New file.
---
 gdb/ChangeLog                                 |  4 ++
 gdb/ada-lang.c                                |  8 +--
 gdb/testsuite/ChangeLog                       |  7 +++
 gdb/testsuite/gdb.ada/array_of_variant.exp    | 52 +++++++++++++++++++
 gdb/testsuite/gdb.ada/array_of_variant/p.adb  | 39 ++++++++++++++
 .../gdb.ada/array_of_variant/pck.adb          | 23 ++++++++
 .../gdb.ada/array_of_variant/pck.ads          | 23 ++++++++
 7 files changed, 153 insertions(+), 3 deletions(-)
 create mode 100644 gdb/testsuite/gdb.ada/array_of_variant.exp
 create mode 100644 gdb/testsuite/gdb.ada/array_of_variant/p.adb
 create mode 100644 gdb/testsuite/gdb.ada/array_of_variant/pck.adb
 create mode 100644 gdb/testsuite/gdb.ada/array_of_variant/pck.ads

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index e81a7877ccb..b06bb68df20 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -2846,9 +2846,11 @@ ada_value_slice_from_ptr (struct value *array_ptr, struct type *type,
       base_low_pos = base_low;
     }
 
-  base = value_as_address (array_ptr)
-    + ((low_pos - base_low_pos)
-       * TYPE_LENGTH (TYPE_TARGET_TYPE (type0)));
+  ULONGEST stride = TYPE_FIELD_BITSIZE (slice_type, 0) / 8;
+  if (stride == 0)
+    stride = TYPE_LENGTH (TYPE_TARGET_TYPE (type0));
+
+  base = value_as_address (array_ptr) + (low_pos - base_low_pos) * stride;
   return value_at_lazy (slice_type, base);
 }
 
diff --git a/gdb/testsuite/gdb.ada/array_of_variant.exp b/gdb/testsuite/gdb.ada/array_of_variant.exp
new file mode 100644
index 00000000000..f2c343fdab0
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/array_of_variant.exp
@@ -0,0 +1,52 @@
+# Copyright 2020 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib "ada.exp"
+
+if { [skip_ada_tests] } { return -1 }
+
+standard_ada_testfile p
+
+foreach_with_prefix scenario {all minimal} {
+    set flags [list debug additional_flags=-fgnat-encodings=$scenario]
+
+    if {[gdb_compile_ada "${srcfile}" "${binfile}" executable $flags] != ""} {
+	return -1
+    }
+
+    clean_restart ${testfile}
+
+    set bp_location [gdb_get_line_number "START" ${testdir}/p.adb]
+    runto "p.adb:$bp_location"
+
+    set v1 "(tag => object, values => (2, 2, 2, 2, 2))"
+    set v2 "(tag => unused)"
+
+    gdb_test "print objects" \
+	[string_to_regexp " = ($v1, $v2)"] \
+	"print entire array"
+    gdb_test "print objects(1)" \
+	[string_to_regexp " = $v1"] \
+	"print first array element"
+    gdb_test "print objects(1 .. 1)" \
+	[string_to_regexp " = ($v1)"] \
+	"print first array slice"
+    gdb_test "print objects(2)" \
+	[string_to_regexp " = $v2"] \
+	"print second array element"
+    gdb_test "print objects(2 .. 2)" \
+	[string_to_regexp " = (2 => $v2)"] \
+	"print second array slice"
+}
diff --git a/gdb/testsuite/gdb.ada/array_of_variant/p.adb b/gdb/testsuite/gdb.ada/array_of_variant/p.adb
new file mode 100644
index 00000000000..d9974ef43bf
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/array_of_variant/p.adb
@@ -0,0 +1,39 @@
+--  Copyright 2020 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+with Pck; use Pck;
+
+procedure P is
+
+   type Tag_T is (Unused, Object);
+
+   type Array_T is array (1 .. Five) of Integer;
+
+   type Payload_T (Tag : Tag_T := Unused) is
+      record
+         case Tag is
+            when Object =>
+               Values : Array_T := (others => 1);
+            when Unused =>
+               null;
+         end case;
+      end record;
+
+   Objects : array (1 .. 2) of Payload_T;
+
+begin
+   Objects (1) := (Tag => Object, Values => (others => 2));
+   Do_Nothing (Objects'Address);  --  START
+end P;
diff --git a/gdb/testsuite/gdb.ada/array_of_variant/pck.adb b/gdb/testsuite/gdb.ada/array_of_variant/pck.adb
new file mode 100644
index 00000000000..af4fe6d6aa7
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/array_of_variant/pck.adb
@@ -0,0 +1,23 @@
+--  Copyright 2020 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package body Pck is
+
+   procedure Do_Nothing (A : System.Address) is
+   begin
+      null;
+   end Do_Nothing;
+
+end Pck;
diff --git a/gdb/testsuite/gdb.ada/array_of_variant/pck.ads b/gdb/testsuite/gdb.ada/array_of_variant/pck.ads
new file mode 100644
index 00000000000..f2a676ca205
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/array_of_variant/pck.ads
@@ -0,0 +1,23 @@
+--  Copyright 2020 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+with System;
+
+package Pck is
+   Five : Integer := 5;
+
+   procedure Do_Nothing (A : System.Address);
+
+end Pck;
-- 
2.26.2


  parent reply	other threads:[~2020-09-30 20:06 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-30 20:05 [PATCH 0/9] Fix most -fgnat-encodings=minimal failures Tom Tromey
2020-09-30 20:05 ` [PATCH 1/9] Avoid crash in ada-lang.c:to_fixed_array_type Tom Tromey
2020-09-30 20:05 ` [PATCH 2/9] Fix decoding of multi-dimensional constrained packed arrays Tom Tromey
2020-09-30 20:05 ` [PATCH 3/9] Synthesize array descriptors with -fgnat-encodings=minimal Tom Tromey
2020-11-06 12:08   ` Luis Machado via Gdb-patches
2020-11-06 17:55     ` Tom Tromey
2020-09-30 20:05 ` [PATCH 4/9] Reject slicing a packed array Tom Tromey
2020-09-30 20:05 ` [PATCH 5/9] Resolve dynamic type in ada_value_struct_elt Tom Tromey
2020-09-30 20:05 ` [PATCH 6/9] Fix bit strides for -fgnat-encodings=minimal Tom Tromey
2020-09-30 20:05 ` [PATCH 7/9] Only use stride for final element type Tom Tromey
2020-09-30 20:05 ` Tom Tromey [this message]
2020-09-30 20:06 ` [PATCH 9/9] Recognize names of array types Tom Tromey
2020-11-04 15:49 ` [PATCH 0/9] Fix most -fgnat-encodings=minimal failures Tom Tromey
2020-11-04 16:33   ` Tom de Vries
2020-11-04 17:20     ` Tom de Vries
2020-11-04 18:52     ` Tom Tromey
2020-11-04 19:54       ` Tom de Vries
2020-11-16 14:32         ` Tom de Vries
2020-11-16 14:01     ` [PATCH][gdb/testsuite] Fix minimal encodings KPASSes Tom de Vries
2020-11-23 19:10       ` [committed][gdb/testsuite] " Tom de Vries

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200930200600.1207702-9-tromey@adacore.com \
    --to=tromey@adacore.com \
    --cc=gdb-patches@sourceware.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox