From 22355c9080f27ed22e4aac714e95729970d48c4b Mon Sep 17 00:00:00 2001 From: Joel Brobecker Date: Thu, 10 Nov 2011 17:14:41 +0000 Subject: [PATCH] read_frame_register_value and big endian arches The read_frame_register_value function as it was implemented introduced a regression on big-endian targets. 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. In that case, we were always reading the first N bytes of the register, which is wrong for big-endian architectures, where we need to read the last N bytes of the register. gdb/ChangeLog: * findvar.c (read_frame_register_value): Read correct bytes from register on big-endian architectures. gdb/testsuite/ChangeLog: * gdb.ada/small_reg_param: New testcase. --- gdb/ChangeLog | 5 +++ gdb/findvar.c | 14 ++++++-- gdb/testsuite/ChangeLog | 4 +++ 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 +++++++++++++ 7 files changed, 131 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/ChangeLog b/gdb/ChangeLog index 405ab84..944155c 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2011-11-10 Joel Brobecker + + * findvar.c (read_frame_register_value): Read the correct bytes + from registers on big-endian architectures. + 2011-11-09 Tom Tromey * procfs.c (load_syscalls): Make a cleanup. 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/ChangeLog b/gdb/testsuite/ChangeLog index 58000b6..8b0abc3 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2011-11-10 Joel Brobecker + + * gdb.ada/small_reg_param: New testcase. + 2011-11-09 Tom Tromey * gdb.cp/destrprint.exp: New file. 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; -- 2.7.4