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# Copyright 2016-2023 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/>.
# Test accessing "non-variable" variables, i.e., variables which are
# optimized to a constant DWARF location expression and/or
# partially/fully optimized out.
load_lib dwarf.exp
require dwarf2_support
standard_testfile main.c -dw.S
# Make some DWARF for the test.
set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
global srcfile
cu {} {
compile_unit {
{DW_AT_name $srcfile}
} {
declare_labels int_type_label char_type_label \
struct_s_label struct_t_label array_a9_label \
char_ptr_label implicit_a_label stack_b_label
int_type_label: base_type {
{name "int"}
{encoding @DW_ATE_signed}
{byte_size 4 DW_FORM_sdata}
}
char_type_label: base_type {
{name "char"}
{encoding @DW_ATE_unsigned}
{byte_size 1 DW_FORM_sdata}
}
char_ptr_label: pointer_type {
{type :$char_type_label}
}
struct_s_label: structure_type {
{name s}
{byte_size 4 DW_FORM_sdata}
} {
member {
{name a}
{type :$int_type_label}
{data_member_location 0 DW_FORM_udata}
{bit_size 8 DW_FORM_udata}
}
member {
{name b}
{type :$int_type_label}
{data_bit_offset 8 DW_FORM_udata}
{bit_size 24 DW_FORM_udata}
}
}
struct_t_label: structure_type {
{name t}
{byte_size 4 DW_FORM_sdata}
} {
member {
{name a}
{type :$int_type_label}
{data_member_location 0 DW_FORM_udata}
{bit_size 9 DW_FORM_udata}
}
member {
{name b}
{type :$int_type_label}
{data_bit_offset 9 DW_FORM_udata}
{bit_size 23 DW_FORM_udata}
}
}
array_a9_label: array_type {
{type :$char_type_label}
} {
subrange_type {
{type :$int_type_label}
{upper_bound 8 DW_FORM_udata}
}
}
DW_TAG_subprogram {
{MACRO_AT_func {main}}
{DW_AT_external 1 flag}
} {
# Simple variable without location.
DW_TAG_variable {
{name undef_int}
{type :$int_type_label}
}
# Struct variable without location.
DW_TAG_variable {
{name undef_s}
{type :$struct_s_label}
}
# Composite location: byte-aligned pieces.
DW_TAG_variable {
{name def_s}
{type :$struct_s_label}
{location {
const1u 0
stack_value
bit_piece 8 0
const1s -1
stack_value
bit_piece 24 0
} SPECIAL_expr}
}
# Composite location: non-byte-aligned pieces.
DW_TAG_variable {
{name def_t}
{type :$struct_t_label}
{location {
const2s -184
stack_value
bit_piece 9 0
const4u 1752286
stack_value
bit_piece 23 0
} SPECIAL_expr}
}
# Composite location with some empty pieces.
DW_TAG_variable {
{name part_def_a}
{type :$array_a9_label}
{location {
piece 3
const4u 0xf1927314
stack_value
piece 4
piece 2
} SPECIAL_expr}
}
# Implicit location: immediate value.
DW_TAG_variable {
{name def_implicit_s}
{type :$struct_s_label}
{location {
implicit_value 0x12 0x34 0x56 0x78
} SPECIAL_expr}
}
# Implicit location: immediate value for whole array, with
# excess bytes.
implicit_a_label: DW_TAG_variable {
{name def_implicit_a}
{type :$array_a9_label}
{location {
implicit_value 0x1 0x12 0x23 0x34 0x45 \
0x56 0x67 0x78 0x89 0x9a 0xab
} SPECIAL_expr}
}
# Implicit pointer into immediate value.
DW_TAG_variable {
{name implicit_a_ptr}
{type :$char_ptr_label}
{location {
implicit_pointer $implicit_a_label 5
} SPECIAL_expr}
}
# Stack-value location.
stack_b_label: DW_TAG_variable {
{name def_stack_b}
{type :$struct_t_label}
{location {
const4u 0x1a2b3c4d
stack_value
} SPECIAL_expr}
}
# Implicit pointer into stack value.
DW_TAG_variable {
{name implicit_b_ptr}
{type :$char_ptr_label}
{location {
implicit_pointer $stack_b_label 1
} SPECIAL_expr}
}
}
}
}
}
if { [prepare_for_testing "failed to prepare" ${testfile} \
[list $srcfile $asm_file] {nodebug}] } {
return -1
}
if ![runto_main] {
return -1
}
# Determine byte order.
set endian [get_endianness]
# Byte-aligned objects with simple location descriptions.
switch $endian { big {set val 0x345678} little {set val 0x785634} }
gdb_test "print/x def_implicit_s" " = \\{a = 0x12, b = $val\\}"
gdb_test "print/x def_implicit_s.b" " = $val"
gdb_test "print/x def_implicit_a" \
" = \\{0x1, 0x12, 0x23, 0x34, 0x45, 0x56, 0x67, 0x78, 0x89\\}"
gdb_test "print/x def_implicit_a\[5\]" " = 0x56"
gdb_test "print/x *(char (*)\[5\]) implicit_a_ptr" \
" = \\{0x56, 0x67, 0x78, 0x89, 0x9a\\}"
switch $endian {
big {set val "a = 52, b = 2833485"}
little {set val "a = 77, b = 857502"}
}
gdb_test "print def_stack_b" " = \\{$val\\}"
switch $endian {big {set val 0x2b} little {set val 0x3c}}
gdb_test "print/x *implicit_b_ptr" " = $val"
# Byte-aligned fields, pieced together from DWARF stack values.
gdb_test "print def_s" " = \\{a = 0, b = -1\\}"
switch $endian { big {set val 0x92} little {set val 0x73} }
gdb_test "print/x part_def_a\[4\]" " = $val"
gdb_test "print/x part_def_a\[8\]" " = <optimized out>"
# Non-byte-aligned fields, pieced together from DWARF stack values.
gdb_test "print def_t" " = \\{a = -184, b = 1752286\\}"
# Simple variable without location.
gdb_test "print undef_int" " = <optimized out>"
# Member of a structure without location.
gdb_test "print undef_s.a" " = <optimized out>"
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