libdw,readelf: Recognize DW_CFA_AARCH64_negate_ra_state

DW_CFA_AARCH64_negate_ra_state is used on aarch64 to indicate whether
or not the return address is mangled or not. This has the same value
as the DW_CFA_GNU_window_save. So we have to pass around the e_machine
value of the process or core we are inspecting to know which one to
use.

Note that it isn't actually implemented yet. It needs ARMv8.3 hardware.
If we don't have such hardware it is enough to simply ignore the
DW_CFA_AARCH64_negate_ra_state (and not confuse it with
DW_CFA_GNU_window_save) to get backtraces to work on aarch64.

Add a testcase for eu-readelf --debug-dump=frames to show the value
is correctly recognized. Also don't warn we cannot find any DWARF
if we are just dumping frames (those will come from .eh_frame if
there is no .debug_frame).

Signed-off-by: Mark Wielaard <[email protected]>

3 files changed, 181 insertions, 0 deletions

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 61c6cb7c..5f2b1449 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,5 +1,11 @@
 2020-09-03  Mark Wielaard  <[email protected]>
 
+	* run-readelf-frames.sh: New test.
+	* Makefile.am (TESTS): Add run-readelf-frames.sh.
+	(EXTRA_DIST): Likewise.
+
+2020-09-03  Mark Wielaard  <[email protected]>
+
 	* testfile-gnu-property-note-aarch64.bz2: New file.
 	* run-readelf-n.sh: Handle testfile-gnu-property-note-aarch64.
 	* Makefile.am (EXTRA_DIST): Add
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 939bbb6a..4629ce64 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -125,6 +125,7 @@ TESTS = run-arextract.sh run-arsymtest.sh run-ar.sh newfile test-nlist \
 	run-readelf-test4.sh run-readelf-twofiles.sh \
 	run-readelf-macro.sh run-readelf-loc.sh run-readelf-ranges.sh \
 	run-readelf-aranges.sh run-readelf-line.sh run-readelf-z.sh \
+	run-readelf-frames.sh \
 	run-readelf-n.sh \
 	run-native-test.sh run-bug1-test.sh \
 	run-debuglink.sh run-debugaltlink.sh run-buildid.sh \
@@ -313,6 +314,7 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \
 	     testfile-dwzstr.bz2 testfile-dwzstr.multi.bz2 \
 	     run-readelf-addr.sh run-readelf-str.sh \
 	     run-readelf-types.sh \
+	     run-readelf-frames.sh \
 	     run-readelf-n.sh \
 	     testfile-gnu-property-note.bz2 testfile-gnu-property-note.o.bz2 \
 	     testfile_gnu_props.32le.o.bz2 \
diff --git a/tests/run-readelf-frames.sh b/tests/run-readelf-frames.sh
new file mode 100755
index 00000000..f0429d19
--- /dev/null
+++ b/tests/run-readelf-frames.sh
@@ -0,0 +1,173 @@
+#! /bin/sh
+# Copyright (C) 2020 Red Hat, Inc.
+# This file is part of elfutils.
+#
+# This file 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.
+#
+# elfutils 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/>.
+
+. $srcdir/test-subr.sh
+
+# See run-readelf-n.sh
+testfiles testfile-gnu-property-note-aarch64
+
+testrun_compare ${abs_top_builddir}/src/readelf --debug-dump=frames testfile-gnu-property-note-aarch64 <<\EOF
+
+Call frame search table section [17] '.eh_frame_hdr':
+ version:          1
+ eh_frame_ptr_enc: 0x1b (sdata4 pcrel)
+ fde_count_enc:    0x3 (udata4)
+ table_enc:        0x3b (sdata4 datarel)
+ eh_frame_ptr:     0x44 (offset: 0x758)
+ fde_count:        7
+ Table:
+  0xfffffe70 (offset:  0x580) -> 0x5c fde=[    14]
+  0xfffffea0 (offset:  0x5b0) -> 0x70 fde=[    28]
+  0xfffffee0 (offset:  0x5f0) -> 0x84 fde=[    3c]
+  0xffffff20 (offset:  0x630) -> 0xac fde=[    64]
+  0xffffff28 (offset:  0x638) -> 0xc0 fde=[    78]
+  0xffffff40 (offset:  0x650) -> 0xd8 fde=[    90]
+  0xffffffc0 (offset:  0x6d0) -> 0x110 fde=[    c8]
+
+Call frame information section [18] '.eh_frame' at offset 0x758:
+
+ [     0] CIE length=16
+   CIE_id:                   0
+   version:                  1
+   augmentation:             "zR"
+   code_alignment_factor:    4
+   data_alignment_factor:    -8
+   return_address_register:  30
+   Augmentation data:        0x1b (FDE address encoding: sdata4 pcrel)
+
+   Program:
+     def_cfa r31 (sp) at offset 0
+
+ [    14] FDE length=16 cie=[     0]
+   CIE_pointer:              24
+   initial_location:         0x0000000000400580 (offset: 0x580)
+   address_range:            0x30 (end offset: 0x5b0)
+
+   Program:
+     nop
+     nop
+     nop
+
+ [    28] FDE length=16 cie=[     0]
+   CIE_pointer:              44
+   initial_location:         0x00000000004005b0 (offset: 0x5b0)
+   address_range:            0x3c (end offset: 0x5ec)
+
+   Program:
+     nop
+     nop
+     nop
+
+ [    3c] FDE length=36 cie=[     0]
+   CIE_pointer:              64
+   initial_location:         0x00000000004005f0 (offset: 0x5f0)
+   address_range:            0x38 (end offset: 0x628)
+
+   Program:
+     advance_loc 1 to 0x5f4
+     AARCH64_negate_ra_state
+     advance_loc 1 to 0x5f8
+     def_cfa_offset 32
+     offset r29 (x29) at cfa-32
+     offset r30 (x30) at cfa-24
+     advance_loc 2 to 0x600
+     offset r19 (x19) at cfa-16
+     advance_loc 8 to 0x620
+     restore r30 (x30)
+     restore r29 (x29)
+     restore r19 (x19)
+     def_cfa_offset 0
+     advance_loc 1 to 0x624
+     AARCH64_negate_ra_state
+     nop
+     nop
+     nop
+
+ [    64] FDE length=16 cie=[     0]
+   CIE_pointer:              104
+   initial_location:         0x0000000000400630 (offset: 0x630)
+   address_range:            0x8 (end offset: 0x638)
+
+   Program:
+     nop
+     nop
+     nop
+
+ [    78] FDE length=20 cie=[     0]
+   CIE_pointer:              124
+   initial_location:         0x0000000000400638 (offset: 0x638)
+   address_range:            0xc (end offset: 0x644)
+
+   Program:
+     nop
+     nop
+     nop
+     nop
+     nop
+     nop
+     nop
+
+ [    90] FDE length=52 cie=[     0]
+   CIE_pointer:              148
+   initial_location:         0x0000000000400650 (offset: 0x650)
+   address_range:            0x80 (end offset: 0x6d0)
+
+   Program:
+     advance_loc 1 to 0x654
+     AARCH64_negate_ra_state
+     advance_loc 1 to 0x658
+     def_cfa_offset 64
+     offset r29 (x29) at cfa-64
+     offset r30 (x30) at cfa-56
+     advance_loc 2 to 0x660
+     offset r19 (x19) at cfa-48
+     offset r20 (x20) at cfa-40
+     advance_loc 3 to 0x66c
+     offset r21 (x21) at cfa-32
+     offset r22 (x22) at cfa-24
+     advance_loc 5 to 0x680
+     offset r23 (x23) at cfa-16
+     offset r24 (x24) at cfa-8
+     advance_loc 18 to 0x6c8
+     restore r30 (x30)
+     restore r29 (x29)
+     restore r23 (x23)
+     restore r24 (x24)
+     restore r21 (x21)
+     restore r22 (x22)
+     restore r19 (x19)
+     restore r20 (x20)
+     def_cfa_offset 0
+     advance_loc 1 to 0x6cc
+     AARCH64_negate_ra_state
+     nop
+     nop
+
+ [    c8] FDE length=16 cie=[     0]
+   CIE_pointer:              204
+   initial_location:         0x00000000004006d0 (offset: 0x6d0)
+   address_range:            0x8 (end offset: 0x6d8)
+
+   Program:
+     nop
+     nop
+     nop
+
+ [    dc] Zero terminator
+EOF
+
+exit 0