From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24631 invoked by alias); 31 Oct 2011 01:03:49 -0000 Received: (qmail 24622 invoked by uid 22791); 31 Oct 2011 01:03:47 -0000 X-SWARE-Spam-Status: No, hits=-2.6 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from rock.gnat.com (HELO rock.gnat.com) (205.232.38.15) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 31 Oct 2011 01:03:31 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id EA8F72BB1F6; Sun, 30 Oct 2011 21:03:29 -0400 (EDT) Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 2pwPWB398I6u; Sun, 30 Oct 2011 21:03:29 -0400 (EDT) Received: from joel.gnat.com (localhost.localdomain [127.0.0.1]) by rock.gnat.com (Postfix) with ESMTP id 4512F2BB1E9; Sun, 30 Oct 2011 21:03:29 -0400 (EDT) Received: by joel.gnat.com (Postfix, from userid 1000) id 717D6145615; Sun, 30 Oct 2011 21:03:22 -0400 (EDT) From: Joel Brobecker To: gdb-patches@sourceware.org Cc: Joel Brobecker Subject: [RFA] read_frame_register_value and big endian arches Date: Mon, 31 Oct 2011 03:17:00 -0000 Message-Id: <1320022996-14705-1-git-send-email-brobecker@adacore.com> In-Reply-To: <20111026213726.GV19246@adacore.com> References: <20111026213726.GV19246@adacore.com> Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2011-10/txt/msg00814.txt.bz2 Hello, I am afraid I introduced a regression on big-endian architectures (Eg. sparc-solaris, erc32-elf) after my latest patch: [RFA/RFC] Restore old handling of multi-register variables http://www.sourceware.org/ml/gdb-patches/2011-10/msg00709.html It's just an oversight: The problem appears when trying to get the value of an entity stored inside a register, and when the size of the entity is smaller than the size of the register. For instance, the testcase shows a parameter whose type is a 2-byte integer. This parameter is passed by register, in a 4-byte register. In that case, the new function read_frame_register_value was always reading from the first bytes of the register, which is wrong for big-endian architectures. gdb/ChangeLog: * findvar.c (read_frame_register_value): Read the correct bytes from registers on big-endian architectures. gdb/testsuite/ChangeLog: * gdb.ada/small_reg_param: New testcase. Tested on x86_64-linux. Also tested on erc32-elf and sparc-solaris, but with AdaCore's testsuite (I am still forbidden from running the testsuite on any of our Solaris machine because it crashes the system really bad). I also checked the patch against AVR, and make sure that it does not create any regression there. Also included is a new testcase which, when run manually, reproduces the problem on erc32-elf, and probably on sparc-solaris too. --- gdb/findvar.c | 14 ++++++-- gdb/testsuite/gdb.ada/small_reg_param.exp | 46 +++++++++++++++++++++++++ gdb/testsuite/gdb.ada/small_reg_param/foo.adb | 21 +++++++++++ gdb/testsuite/gdb.ada/small_reg_param/pck.adb | 22 ++++++++++++ gdb/testsuite/gdb.ada/small_reg_param/pck.ads | 22 ++++++++++++ 5 files changed, 122 insertions(+), 3 deletions(-) create mode 100644 gdb/testsuite/gdb.ada/small_reg_param.exp create mode 100644 gdb/testsuite/gdb.ada/small_reg_param/foo.adb create mode 100644 gdb/testsuite/gdb.ada/small_reg_param/pck.adb create mode 100644 gdb/testsuite/gdb.ada/small_reg_param/pck.ads diff --git a/gdb/findvar.c b/gdb/findvar.c index 54e7b4a..426b488 100644 --- a/gdb/findvar.c +++ b/gdb/findvar.c @@ -641,11 +641,19 @@ read_frame_register_value (struct value *value, struct frame_info *frame) { struct value *regval = get_frame_register_value (frame, regnum); int reg_len = TYPE_LENGTH (value_type (regval)); + int reg_offset = 0; + /* If the register length is larger than the number of bytes + remaining to copy, then only copy the appropriate bytes. */ if (offset + reg_len > len) - reg_len = len - offset; - value_contents_copy (value, offset, regval, value_offset (regval), - reg_len); + { + reg_len = len - offset; + if (gdbarch_byte_order (get_frame_arch (frame)) == BFD_ENDIAN_BIG) + reg_offset = TYPE_LENGTH (value_type (regval)) - reg_len; + } + + value_contents_copy (value, offset, regval, + value_offset (regval) + reg_offset, reg_len); offset += reg_len; regnum++; diff --git a/gdb/testsuite/gdb.ada/small_reg_param.exp b/gdb/testsuite/gdb.ada/small_reg_param.exp new file mode 100644 index 0000000..00b066b --- /dev/null +++ b/gdb/testsuite/gdb.ada/small_reg_param.exp @@ -0,0 +1,46 @@ +# Copyright 2011 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 . + +load_lib "ada.exp" + +set testdir "small_reg_param" +set testfile "${testdir}/foo" +set srcfile ${srcdir}/${subdir}/${testfile}.adb +set binfile ${objdir}/${subdir}/${testfile} + +file mkdir ${objdir}/${subdir}/${testdir} +if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug optimize=-O1]] != "" } { + return -1 +} + +clean_restart ${testfile} + +if ![runto main] then { + perror "Couldn't run ${testfile}" + return +} + +gdb_breakpoint "call_me" + +# Continue until we hit the breakpoint inside `Call_Me'. We verify +# that the parameter value is correct. +gdb_test "continue" \ + "Breakpoint .*, pck\\.call_me \\(w=50\\) at .*/pck.adb:.*" \ + "continue to call_me" + +# And just to make sure, we also verify that the parameter value +# is correct when we print it manually. +gdb_test "print w" " = 50" + diff --git a/gdb/testsuite/gdb.ada/small_reg_param/foo.adb b/gdb/testsuite/gdb.ada/small_reg_param/foo.adb new file mode 100644 index 0000000..e6b1f53 --- /dev/null +++ b/gdb/testsuite/gdb.ada/small_reg_param/foo.adb @@ -0,0 +1,21 @@ +-- Copyright 2011 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 . + +with Pck; use Pck; + +procedure Foo is +begin + Call_Me (50); +end Foo; diff --git a/gdb/testsuite/gdb.ada/small_reg_param/pck.adb b/gdb/testsuite/gdb.ada/small_reg_param/pck.adb new file mode 100644 index 0000000..55455c7 --- /dev/null +++ b/gdb/testsuite/gdb.ada/small_reg_param/pck.adb @@ -0,0 +1,22 @@ +-- Copyright 2011 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 . + +package body Pck is + Last_Word : Word := 0; + procedure Call_Me (W : Word) is + begin + Last_Word := W; + end Call_Me; +end Pck; diff --git a/gdb/testsuite/gdb.ada/small_reg_param/pck.ads b/gdb/testsuite/gdb.ada/small_reg_param/pck.ads new file mode 100644 index 0000000..7ae299a --- /dev/null +++ b/gdb/testsuite/gdb.ada/small_reg_param/pck.ads @@ -0,0 +1,22 @@ +-- Copyright 2011 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 . + +package Pck is + + type Word is range 0 .. 16#FFFF#; + for Word'size use 16; + + procedure Call_Me (W : Word); +end Pck; -- 1.7.1