[gdb/testsuite] Add .debug_loc support in dwarf assembler
Add .debug_loc support in the dwarf assembler, and use it in new test-case
gdb.dwarf2/loc-sec-offset.exp (which is based on
gdb.dwarf2/loclists-sec-offset.exp).
Tested on x86_64-linux.
diff --git a/gdb/testsuite/gdb.dwarf2/loc-sec-offset.c b/gdb/testsuite/gdb.dwarf2/loc-sec-offset.c
new file mode 100644
index 0000000..2bffbf2
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/loc-sec-offset.c
@@ -0,0 +1,37 @@
+/* Copyright (C) 2021 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+static int
+func1 (void)
+{
+ asm ("func1_label: .global func1_label\n");
+ return 1;
+}
+
+static int
+func2 (void)
+{
+ asm ("func2_label: .global func2_label\n");
+ return 2;
+}
+
+int
+main (void)
+{
+ func1 ();
+ func2 ();
+}
diff --git a/gdb/testsuite/gdb.dwarf2/loc-sec-offset.exp b/gdb/testsuite/gdb.dwarf2/loc-sec-offset.exp
new file mode 100644
index 0000000..2ec66b3
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/loc-sec-offset.exp
@@ -0,0 +1,121 @@
+# Copyright 2021 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 DW_AT_location attribute referencing the .debug_loc section using
+# the DW_FORM_sec_offset form.
+
+load_lib dwarf.exp
+
+if {![dwarf2_support]} {
+ return 0
+}
+
+# Test with 32-bit and 64-bit DWARF.
+foreach_with_prefix is_64 {false true} {
+ if { $is_64 } {
+ standard_testfile .c -dw64.S
+ set testfile ${testfile}-dw64
+ } else {
+ standard_testfile .c -dw32.S
+ set testfile ${testfile}-dw32
+ }
+
+ lassign [function_range func1 $srcdir/$subdir/$srcfile] \
+ func1_addr func1_len
+ lassign [function_range func2 $srcdir/$subdir/$srcfile] \
+ func2_addr func2_len
+
+ set asm_file [standard_output_file $srcfile2]
+ Dwarf::assemble $asm_file {
+ global func1_addr func1_len
+ global func2_addr func2_len
+ global is_64
+
+ set cu_version 4
+
+ cu {
+ version $cu_version
+ is_64 $is_64
+ } {
+ declare_labels int_type1
+ declare_labels foo_location_list
+
+ DW_TAG_compile_unit {
+ } {
+ int_type1: DW_TAG_base_type {
+ {DW_AT_byte_size 4 DW_FORM_data1}
+ {DW_AT_encoding @DW_ATE_signed}
+ {DW_AT_name "int"}
+ }
+
+ DW_TAG_variable {
+ {DW_AT_name "foo"}
+ {DW_AT_location $foo_location_list DW_FORM_sec_offset}
+ {DW_AT_type :$int_type1}
+ }
+
+ DW_TAG_subprogram {
+ {DW_AT_name "func1"}
+ {DW_AT_low_pc $func1_addr}
+ {DW_AT_high_pc $func1_len DW_FORM_udata}
+ }
+
+ DW_TAG_subprogram {
+ {DW_AT_name "func2"}
+ {DW_AT_low_pc $func2_addr}
+ {DW_AT_high_pc $func2_len DW_FORM_udata}
+ }
+ }
+ }
+
+ # Generate a .debug_loc contribution.
+ loc {
+ cu_is_64 $is_64
+ cu_version $cu_version
+ } {
+ foo_location_list:
+ entry $func1_addr "$func1_addr + $func1_len" {
+ DW_OP_constu 0x123456
+ DW_OP_stack_value
+ }
+ entry $func2_addr "$func2_addr + $func2_len" {
+ DW_OP_constu 0x234567
+ DW_OP_stack_value
+ }
+ }
+ }
+
+ if { [prepare_for_testing "failed to prepare" ${testfile} \
+ [list $srcfile $asm_file] {nodebug}] } {
+ return -1
+ }
+
+ if { ![runto_main] } {
+ return
+ }
+
+ gdb_breakpoint "func1"
+ gdb_breakpoint "func2"
+
+ gdb_continue_to_breakpoint "func1"
+ with_test_prefix "at func1" {
+ gdb_test "print /x foo" " = 0x123456"
+ }
+
+ gdb_continue_to_breakpoint "func2"
+ with_test_prefix "at func2" {
+ gdb_test "print /x foo" " = 0x234567"
+ }
+}
diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp
index 66f9844..b48cfad 100644
--- a/gdb/testsuite/lib/dwarf.exp
+++ b/gdb/testsuite/lib/dwarf.exp
@@ -2369,6 +2369,105 @@
aranges_end:
}
+ # Emit a .debug_loc entry.
+
+ proc _loc_entry { start end location_description } {
+ # Determine how to emit addresses.
+ variable _addr_size
+ if { $_addr_size == 8 } {
+ set addr_op .8byte
+ } elseif { $_addr_size == 4 } {
+ set addr_op .4byte
+ }
+
+ # Emit start and end address.
+ _op $addr_op $start "Start address"
+ _op $addr_op $end "End address"
+
+ declare_labels location_description_start
+ declare_labels location_description_end
+
+ # Emit length of location description.
+ set len "$location_description_end - $location_description_start"
+ _op .2byte $len "Location description length"
+
+ # Tag start of location description.
+ define_label $location_description_start
+
+ # Emit location description.
+ variable _cu_version
+ variable _cu_offset_size
+ _location $location_description $_cu_version $_addr_size \
+ $_cu_offset_size
+
+ # Tag end of location description.
+ define_label $location_description_end
+ }
+
+ # Emit a DWARF .debug_loc contribution.
+ #
+ # OPTIONS is a list with an even number of elements containing
+ # option-name and option-value pairs.
+ # Current options are:
+ # cu_is_64 0|1 - boolean indicating if references from location
+ # descriptions refer to a 64-bit DWARF CU.
+ # default = 0 (32-bit)
+ # cu_version n - section version of DWARF CU referenced from location
+ # descriptions.
+ # default = 4
+ #
+ # BODY is Tcl code that emits the parts which make up the body of
+ # the debug_loc contribution. It is evaluated in the caller's context.
+ # The following command is available for the BODY section:
+ #
+ # entry <start> <end> <location description>
+ # -- emit a .debug_loc entry
+
+ proc loc { options body } {
+ # Handle options.
+ parse_options {
+ { cu_version 4 }
+ { cu_is_64 0 }
+ }
+
+ # Export for use in BODY.
+ variable _addr_size
+ if { [is_64_target] } {
+ set _addr_size 8
+ } else {
+ set _addr_size 4
+ }
+ variable _cu_version
+ set _cu_version $cu_version
+ variable _cu_offset_size
+ if { $cu_is_64 == 1 } {
+ set _cu_offset_size 8
+ } else {
+ set _cu_offset_size 4
+ }
+
+ # Switch to .debug_loc section.
+ _section .debug_loc
+
+ # Introduce command 'entry'.
+ with_override Dwarf::entry Dwarf::_loc_entry {
+ # Emit entries.
+ uplevel $body
+ }
+
+ # Determine how to emit addresses.
+ if { $_addr_size == 8 } {
+ set addr_op .8byte
+ } elseif { $_addr_size == 4 } {
+ set addr_op .4byte
+ }
+
+ # Emit <End of list>.
+ set comment "<End of list>"
+ _op $addr_op 0 "$comment (Part 1/2)"
+ _op $addr_op 0 "$comment (Part 2/2)"
+ }
+
proc _empty_array {name} {
upvar $name the_array
