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[binutils-gdb] gdb: Handle multiple base address in debug_ranges data.
- From: Andrew Burgess <aburgess at sourceware dot org>
- To: gdb-cvs at sourceware dot org
- Date: 10 Dec 2015 10:01:45 -0000
- Subject: [binutils-gdb] gdb: Handle multiple base address in debug_ranges data.
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=28d2bfb9c3e519a3b7619bbe5d061ebe520750ef
commit 28d2bfb9c3e519a3b7619bbe5d061ebe520750ef
Author: Andrew Burgess <andrew.burgess@embecosm.com>
Date: Fri Oct 16 10:08:19 2015 +0200
gdb: Handle multiple base address in debug_ranges data.
It is possible to use multiple base addresses within a single address
range series, within the .debug_ranges section. The following is a
simplified example for 32-bit addresses:
.section ".debug_ranges"
.4byte 0xffffffff
.4byte BASE_1
.4byte START_OFFSET_1
.4byte END_OFFSET_1
.4byte START_OFFSET_2
.4byte END_OFFSET_2
.4byte 0xffffffff
.4byte BASE_2
.4byte START_OFFSET_3
.4byte END_OFFSET_3
.4byte 0
.4byte 0
In this example START/END 1 and 2 are relative to BASE_1, while
START/END 3 are relative to BASE_2.
Currently gdb does not correctly parse this DWARF, resulting in
corrupted address range information. This commit fixes this issue, and
adds a new test to cover this case.
In order to support testing of this feature extensions were made to the
testsuite dwarf assembler, additional functionality was added to the
.debug_line generation function, and a new function for generating the
.debug_ranges section was added.
gdb/ChangeLog:
* dwarf2read.c (dwarf2_ranges_read): Unify and fix base address
reading code.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-ranges-base.c: New file.
* gdb.dwarf2/dw2-ranges-base.exp: New file.
* lib/dwarf.exp (namespace eval Dwarf): Add new variables to
support additional line table, and debug ranges generation.
(Dwarf::ranges): New function, generate .debug_ranges.
(Dwarf::lines): Support generating simple line table programs.
(Dwarf::assemble): Initialise new namespace variables.
Diff:
---
gdb/ChangeLog | 5 +
gdb/dwarf2read.c | 19 +--
gdb/testsuite/ChangeLog | 10 ++
gdb/testsuite/gdb.dwarf2/dw2-ranges-base.c | 36 ++++++
gdb/testsuite/gdb.dwarf2/dw2-ranges-base.exp | 143 ++++++++++++++++++++++
gdb/testsuite/lib/dwarf.exp | 175 +++++++++++++++++++++++++--
6 files changed, 362 insertions(+), 26 deletions(-)
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 6aa90d9..1151dc8 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2015-12-10 Andrew Burgess <andrew.burgess@embecosm.com>
+
+ * dwarf2read.c (dwarf2_ranges_read): Unify and fix base address
+ reading code.
+
2015-12-09 Kevin Buettner <kevinb@redhat.com>
* dwarf2loc.c (dwarf2_evaluate_loc_desc_full): Perform a pointer
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 298757c..4881d72 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -11894,7 +11894,6 @@ dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return,
int found_base;
unsigned int dummy;
const gdb_byte *buffer;
- CORE_ADDR marker;
int low_set;
CORE_ADDR low = 0;
CORE_ADDR high = 0;
@@ -11913,18 +11912,6 @@ dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return,
}
buffer = dwarf2_per_objfile->ranges.buffer + offset;
- /* Read in the largest possible address. */
- marker = read_address (obfd, buffer, cu, &dummy);
- if ((marker & mask) == mask)
- {
- /* If we found the largest possible address, then
- read the base address. */
- base = read_address (obfd, buffer + addr_size, cu, &dummy);
- buffer += 2 * addr_size;
- offset += 2 * addr_size;
- found_base = 1;
- }
-
low_set = 0;
baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
@@ -11949,9 +11936,9 @@ dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return,
the base address. Check for a base address here. */
if ((range_beginning & mask) == mask)
{
- /* If we found the largest possible address, then
- read the base address. */
- base = read_address (obfd, buffer + addr_size, cu, &dummy);
+ /* If we found the largest possible address, then we already
+ have the base address in range_end. */
+ base = range_end;
found_base = 1;
continue;
}
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index a367451..bad4382 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,13 @@
+2015-12-10 Andrew Burgess <andrew.burgess@embecosm.com>
+
+ * gdb.dwarf2/dw2-ranges-base.c: New file.
+ * gdb.dwarf2/dw2-ranges-base.exp: New file.
+ * lib/dwarf.exp (namespace eval Dwarf): Add new variables to
+ support additional line table, and debug ranges generation.
+ (Dwarf::ranges): New function, generate .debug_ranges.
+ (Dwarf::lines): Support generating simple line table programs.
+ (Dwarf::assemble): Initialise new namespace variables.
+
2015-12-09 Kevin Buettner <kevinb@redhat.com>
* gdb.base/async.exp (proc test_background): Add case for
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.c b/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.c
new file mode 100644
index 0000000..4d52b6e
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.c
@@ -0,0 +1,36 @@
+/*
+ Copyright 2015 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/>. */
+
+void __attribute__ ((section (".text.3")))
+frame3 (void)
+{
+ asm ("frame3_label: .globl frame3_label");
+}
+
+void __attribute__ ((section (".text.2")))
+frame2 (void)
+{
+ asm ("frame2_label: .globl frame2_label");
+ frame3 ();
+}
+
+void __attribute__ ((section (".text.1")))
+main (void)
+{
+ asm ("main_label: .globl main_label");
+ frame2 ();
+}
+
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.exp b/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.exp
new file mode 100644
index 0000000..9d64270
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-ranges-base.exp
@@ -0,0 +1,143 @@
+# Copyright 2015 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 dwarf.exp
+
+# Test DW_TAG_compile_unit with no children and with neither DW_AT_low_pc nor
+# DW_AT_high_pc but with DW_AT_ranges instead.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+ verbose "Skipping DW_AT_ranges test."
+ return 0
+}
+
+# The .c files use __attribute__.
+if [get_compiler_info] {
+ return -1
+}
+if !$gcc_compiled {
+ verbose "Skipping DW_AT_ranges test."
+ return 0
+}
+
+standard_testfile dw2-ranges-base.c dw2-ranges-base-dw.S
+
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+ global srcdir subdir srcfile srcfile2
+ declare_labels ranges_label
+ declare_labels L
+
+ # Find start address and length for our functions.
+ set main_func \
+ [function_range main [list ${srcdir}/${subdir}/$srcfile]]
+ set frame2_func \
+ [function_range frame2 [list ${srcdir}/${subdir}/$srcfile]]
+ set frame3_func \
+ [function_range frame3 [list ${srcdir}/${subdir}/$srcfile]]
+
+ # Very simple info for this test program. We don't care about
+ # this information being correct (w.r.t. funtion / argument types)
+ # just so long as the compilation using makes use of the
+ # .debug_ranges data then the test achieves its objective.
+ cu {} {
+ compile_unit {
+ {language @DW_LANG_C}
+ {name dw-ranges-base.c}
+ {stmt_list $L DW_FORM_sec_offset}
+ {ranges ${ranges_label} DW_FORM_sec_offset}
+ } {
+ subprogram {
+ {external 1 flag}
+ {name main}
+ }
+ subprogram {
+ {external 1 flag}
+ {name frame2}
+ }
+ subprogram {
+ {external 1 flag}
+ {name frame3}
+ }
+ }
+ }
+
+ lines {version 2} L {
+ include_dir "${srcdir}/${subdir}"
+ file_name "$srcfile" 1
+
+ # Generate simple line table program. The line table
+ # information contained here is not correct, and we really
+ # don't care, just so long as each function has some line
+ # table data associated with it. We do make use of the fake
+ # line numbers that we pick here in the tests below.
+ program {
+ {DW_LNE_set_address [lindex $main_func 0]}
+ {DW_LNS_advance_line 10}
+ {DW_LNS_copy}
+ {DW_LNS_advance_pc [lindex $main_func 1]}
+ {DW_LNS_advance_line 19}
+ {DW_LNS_copy}
+ {DW_LNE_end_sequence}
+
+ {DW_LNE_set_address [lindex $frame2_func 0]}
+ {DW_LNS_advance_line 20}
+ {DW_LNS_copy}
+ {DW_LNS_advance_pc [lindex $frame2_func 1]}
+ {DW_LNS_advance_line 29}
+ {DW_LNS_copy}
+ {DW_LNE_end_sequence}
+
+ {DW_LNE_set_address [lindex $frame3_func 0]}
+ {DW_LNS_advance_line 30}
+ {DW_LNS_copy}
+ {DW_LNS_advance_pc [lindex $frame3_func 1]}
+ {DW_LNS_advance_line 39}
+ {DW_LNS_copy}
+ {DW_LNE_end_sequence}
+ }
+ }
+
+ # Generate ranges data. This is the point of this whole test
+ # file, we must have multiple bases specified, so we use a new
+ # base for each function.
+ ranges {is_64 [is_64_target]} {
+ ranges_label: sequence {
+ {base [lindex $main_func 0]}
+ {range 0 [lindex $main_func 1]}
+ {base [lindex $frame2_func 0]}
+ {range 0 [lindex $frame2_func 1]}
+ {base [lindex $frame3_func 0]}
+ {range 0 [lindex $frame3_func 1]}
+ }
+ }
+}
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} \
+ [list $srcfile $asm_file] {nodebug}] } {
+ return -1
+}
+
+if ![runto_main] {
+ return -1
+}
+
+# Make use of the line numbers we faked in the .debug_line table above.
+gdb_test "info line main" \
+ "Line 11 of .* starts at address .* and ends at .*"
+gdb_test "info line frame2" \
+ "Line 21 of .* starts at address .* and ends at .*"
+gdb_test "info line frame3" \
+ "Line 31 of .* starts at address .* and ends at .*"
diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp
index c87da87..44200a1 100644
--- a/gdb/testsuite/lib/dwarf.exp
+++ b/gdb/testsuite/lib/dwarf.exp
@@ -303,6 +303,15 @@ namespace eval Dwarf {
# Whether a file_name entry was seen.
variable _line_saw_file
+ # Whether a line table program has been seen.
+ variable _line_saw_program
+
+ # A Label for line table header generation.
+ variable _line_header_end_label
+
+ # The address size for debug ranges section.
+ variable _debug_ranges_64_bit
+
proc _process_one_constant {name value} {
variable _constants
variable _AT
@@ -992,7 +1001,7 @@ namespace eval Dwarf {
set _cu_label [_compute_label "cu${cu_num}_begin"]
set start_label [_compute_label "cu${cu_num}_start"]
set end_label [_compute_label "cu${cu_num}_end"]
-
+
define_label $_cu_label
if {$is_64} {
_op .4byte 0xffffffff
@@ -1129,6 +1138,78 @@ namespace eval Dwarf {
define_label $end_label
}
+ # Emit a DWARF .debug_ranges unit.
+ # OPTIONS is a list with an even number of elements containing
+ # option-name and option-value pairs.
+ # Current options are:
+ # is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
+ # default = 0 (32-bit)
+ #
+ # BODY is Tcl code that emits the content of the .debug_ranges
+ # unit, it is evaluated in the caller's context.
+ proc ranges {options body} {
+ variable _debug_ranges_64_bit
+
+ foreach { name value } $options {
+ switch -exact -- $name {
+ is_64 { set _debug_ranges_64_bit [subst $value] }
+ default { error "unknown option $name" }
+ }
+ }
+
+ set section ".debug_ranges"
+ _section $section
+
+ proc sequence {{ranges {}}} {
+ variable _debug_ranges_64_bit
+
+ # Emit the sequence of addresses.
+ set base ""
+ foreach range $ranges {
+ set range [uplevel 1 "subst \"$range\""]
+ set type [lindex $range 0]
+ switch -exact -- $type {
+ base {
+ set base [lrange $range 1 end]
+
+ if { $_debug_ranges_64_bit } then {
+ _op .8byte 0xffffffffffffffff "Base Marker"
+ _op .8byte $base "Base Address"
+ } else {
+ _op .4byte 0xffffffff "Base Marker"
+ _op .4byte $base "Base Address"
+ }
+ }
+ range {
+ set start [lindex $range 1]
+ set end [lrange $range 2 end]
+
+ if { $_debug_ranges_64_bit } then {
+ _op .8byte $start "Start Address"
+ _op .8byte $end "End Address"
+ } else {
+ _op .4byte $start "Start Address"
+ _op .4byte $end "End Address"
+ }
+ }
+ default { error "unknown range type: $type " }
+ }
+ }
+
+ # End of the sequence.
+ if { $_debug_ranges_64_bit } then {
+ _op .8byte 0x0 "End of Sequence Marker (Part 1)"
+ _op .8byte 0x0 "End of Sequence Marker (Part 2)"
+ } else {
+ _op .4byte 0x0 "End of Sequence Marker (Part 1)"
+ _op .4byte 0x0 "End of Sequence Marker (Part 2)"
+ }
+ }
+
+ uplevel $body
+ }
+
+
# Emit a DWARF .debug_line unit.
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
@@ -1157,6 +1238,8 @@ namespace eval Dwarf {
proc lines {options label body} {
variable _line_count
variable _line_saw_file
+ variable _line_saw_program
+ variable _line_header_end_label
# Establish the defaults.
set is_64 0
@@ -1192,7 +1275,7 @@ namespace eval Dwarf {
set unit_len_label [_compute_label "line${_line_count}_start"]
set unit_end_label [_compute_label "line${_line_count}_end"]
set header_len_label [_compute_label "line${_line_count}_header_start"]
- set header_end_label [_compute_label "line${_line_count}_header_end"]
+ set _line_header_end_label [_compute_label "line${_line_count}_header_end"]
if {$is_64} {
_op .4byte 0xffffffff
@@ -1206,20 +1289,34 @@ namespace eval Dwarf {
_op .2byte $_unit_version version
if {$is_64} {
- _op .8byte "$header_end_label - $header_len_label" "header_length"
+ _op .8byte "$_line_header_end_label - $header_len_label" "header_length"
} else {
- _op .4byte "$header_end_label - $header_len_label" "header_length"
+ _op .4byte "$_line_header_end_label - $header_len_label" "header_length"
}
define_label $header_len_label
_op .byte 1 "minimum_instruction_length"
- _op .byte 0 "default_is_stmt"
+ _op .byte 1 "default_is_stmt"
_op .byte 1 "line_base"
_op .byte 1 "line_range"
- _op .byte 1 "opcode_base"
- # Since we emit opcode_base==1, we skip
- # standard_opcode_length table altogether.
+ _op .byte 10 "opcode_base"
+
+ # The standard_opcode_lengths table. The number of arguments
+ # for each of the standard opcodes. Generating 9 entries here
+ # matches the use of 10 in the opcode_base above. These 9
+ # entries match the 9 standard opcodes for DWARF2, making use
+ # of only 9 should be fine, even if we are generating DWARF3
+ # or DWARF4.
+ _op .byte 0 "standard opcode 1"
+ _op .byte 1 "standard opcode 2"
+ _op .byte 1 "standard opcode 3"
+ _op .byte 1 "standard opcode 4"
+ _op .byte 1 "standard opcode 5"
+ _op .byte 0 "standard opcode 6"
+ _op .byte 0 "standard opcode 7"
+ _op .byte 0 "standard opcode 8"
+ _op .byte 1 "standard opcode 9"
proc include_dir {dirname} {
_op .ascii [_quote $dirname]
@@ -1239,6 +1336,57 @@ namespace eval Dwarf {
_op .sleb128 0 "length"
}
+ proc program {statements} {
+ variable _line_saw_program
+ variable _line_header_end_label
+
+ if "! $_line_saw_program" {
+ # Terminate the file list.
+ _op .byte 0 "Terminator."
+ define_label $_line_header_end_label
+ set _line_saw_program 1
+ }
+
+ proc DW_LNE_set_address {addr} {
+ _op .byte 0
+ set start [new_label "set_address_start"]
+ set end [new_label "set_address_end"]
+ _op .uleb128 "${end} - ${start}"
+ define_label ${start}
+ _op .byte 2
+ if {[is_64_target]} {
+ _op .8byte ${addr}
+ } else {
+ _op .4byte ${addr}
+ }
+ define_label ${end}
+ }
+
+ proc DW_LNE_end_sequence {} {
+ _op .byte 0
+ _op .uleb128 1
+ _op .byte 1
+ }
+
+ proc DW_LNS_copy {} {
+ _op .byte 1
+ }
+
+ proc DW_LNS_advance_pc {offset} {
+ _op .byte 2
+ _op .uleb128 ${offset}
+ }
+
+ proc DW_LNS_advance_line {offset} {
+ _op .byte 3
+ _op .sleb128 ${offset}
+ }
+
+ foreach statement $statements {
+ uplevel 1 $statement
+ }
+ }
+
uplevel $body
rename include_dir ""
@@ -1250,9 +1398,11 @@ namespace eval Dwarf {
}
# Terminate the file list.
- _op .byte 0 "Terminator."
+ if "! $_line_saw_program" {
+ _op .byte 0 "Terminator."
+ define_label $_line_header_end_label
+ }
- define_label $header_end_label
define_label $unit_end_label
}
@@ -1337,6 +1487,9 @@ namespace eval Dwarf {
variable _cu_count
variable _line_count
variable _line_saw_file
+ variable _line_saw_program
+ variable _line_header_end_label
+ variable _debug_ranges_64_bit
if {!$_initialized} {
_read_constants
@@ -1352,6 +1505,8 @@ namespace eval Dwarf {
set _line_count 0
set _line_saw_file 0
+ set _line_saw_program 0
+ set _debug_ranges_64_bit [is_64_target]
# Not "uplevel" here, because we want to evaluate in this
# namespace. This is somewhat bad because it means we can't