Commit graph

130 commits

Author SHA1 Message Date
Christopher Ferris
95a524460a Merge "Cache DWARF location rules for a given pc." 2018-03-29 14:47:35 +00:00
David Srbecky
3386ebade2 Cache DWARF location rules for a given pc.
Decoding the DWARF opcodes is expensive so make sure we cache it.

This speeds unwinding in simpleperf by over a factor of 3x.

Add unit tests for this new behavior.

Bug: 77258731

Test: libbacktrace/libunwindstack unit tests on host and target.
Test: Ran debuggerd -b on various processes on target.
Change-Id: Ia516c0fa5d3e5f76746190bb4b6fdf49fd1c9388
2018-03-29 14:47:13 +00:00
Christopher Ferris
6dbc28ece3 Fix null pointer dereference in RegsArm.
Fix RegsArm::GetPcAdjustment to check for an invalid elf before trying
to read memory.
Modify the tests for this so it crashes without this change.

Also modify the GetPcAdjustment for all different architectures so
that unless the relative pc is too small, it will return the minimum
amount that should be adjusted. This is to handle cases where we still
want to adjust the pc but it's in an invalid elf. Mostly this is for
handling cases when the pc is in jit gdb debug code so that we use the
right unwind information.

Bug: 77233204

Test: Passes unit tests for libbacktrace/libunwindstack.
Change-Id: Id73609adaf3b80a583584441de228156fec3afa7
2018-03-28 17:21:01 -07:00
Yabin Cui
d5b22c5f04 Support a map that represents gdb jit elf data.
Changes:
- Add a new flag to the libbacktrace and libunwindstack map data.
- Modify the unwinder to handle this map to use the raw pc when stepping.
- Add new unit tests for this case.

Bug: http://b/73127105
Test: Run simpleperf to unwind through jit symfiles.
Test: Run new unit tests.
Test: Run 137-cfi test on host.
Change-Id: I10bc0410680accc6d35fe51e9f1098911f667e01
2018-03-21 17:23:54 -07:00
Christopher Ferris
b22451f178 Merge "Always set the sp reg to the cfa for DWARF." 2018-03-19 17:48:59 +00:00
David Srbecky
e8d1b75c0c Merge "Don't include map name if the consumer doesn't want names." 2018-03-19 11:23:10 +00:00
David Srbecky
e62f4c4d4c Don't include map name if the consumer doesn't want names.
Simpleperf doesn't need the name, so avoid the string copies.

This seems to speed up simpleperf by around 20%.

Test: backtrace_test libunwindstack_test
Change-Id: Iba064c7078f7e5ecfc9d8539ba09c14495a52158
2018-03-19 11:20:00 +00:00
Yabin Cui
11e96fe48a Always set the sp reg to the cfa for DWARF.
There are a few places where it is assumed that this register is
set to the cfa value when interpreting DWARF information.

Add a testcase for unwinding art_quick_osr_stub on ARM.

Bug: 73954823

Test: Ran libunwindstack/libbacktrace unit tests.
Test: Random debuggerd -b of process on a hikey.
Test: Ran the 137 art test on host.
Change-Id: Ida6ccdc38c3cfeea6b57fe861a0cc127b150b790
2018-03-16 23:38:07 -07:00
Christopher Ferris
704ec9adba Handle ARM thumb function symbols.
ARM thumb functions will have the zero bit set to one, which can cause
function name lookups to fail.

Add an ARM special GetFunctionName that handles this condition.

Fix a couple of the function offsets in unit tests.

Bug: 74844137

Test: Ran unit tests.
Test: Ran debuggerd -b on processes on a bullhead device.
Change-Id: Ibd407db34eaaa641f91fdb4f589c44a0dcc0216a
2018-03-15 15:14:18 -07:00
David Srbecky
ff9b1db67c Merge "Remove libunwindstack_dex" 2018-03-13 11:31:22 +00:00
David Srbecky
18121dc4d0 Remove libunwindstack_dex
Thanks to David Sehr's recent work the isolation is no longer needed.

Bug: 72216369
Test: backtrace_test
Test: libunwindstack_test
Test: testrunner.py -t 137
Change-Id: I0f430e0c18bdbc83c5584a2461ebbcc7eeb91313
2018-03-12 20:13:21 +00:00
David Srbecky
3692f25199 Don't implicitly dereference DW_CFA_def_cfa_expression.
The specification isn't entirely clear. Follow the gdb interpretation.

Bug: 73954823
Test: libunwindstack_test
Change-Id: If72717f54eed84e442f43af19e615143a9796b68
2018-03-08 14:44:11 -08:00
Christopher Ferris
81744ac69f Remove leftover commented out code.
Test: Compiles.
Change-Id: Icf1cf1640e76450d5327395eb94dbd87d2faac36
2018-03-06 11:24:55 -08:00
David Srbecky
8fbdbba9f5 Merge "Adjust DEX file reading to follow layout changes in ART." 2018-02-23 17:53:23 +00:00
Christopher Ferris
a2ec50bf57 Change the GetAdjustedRelPc to GetPcAdjustment.
This cleans up a bit of the Unwinder code to make it clear what's
going on.

Modify the offline unit tests to verify the pc and sp to make sure
that those values get computed correctly.

Test: Passes unit tests.
Test: Passes 137-cfi art tests.
Change-Id: I0787a1d77b8726d3defd08f31c7476f6798f8d0d
2018-02-21 20:16:39 -08:00
Christopher Ferris
e4b3a6aaa4 Add ability to skip function name resolution.
Bug: 73558129

Test: New unit tests pass.
Change-Id: I3a6b17d2590aacb367ab3e3a51cc85be73ad64eb
2018-02-20 17:10:23 -08:00
Treehugger Robot
0609e8d231 Merge "bpfmt." 2018-02-20 02:02:59 +00:00
Elliott Hughes
dc699a269f bpfmt.
Bug: N/A
Test: builds
Change-Id: I89ad00e1c4c7e0767bc80a7ac7935a4d55e090ac
2018-02-16 17:58:14 -08:00
Christopher Ferris
d9575b668b Modify elf cache to handle elf_offsets properly.
Bug: 73498823

Test: All unit tests pass.
Test: Simpleperf run that previously failed, passes now.
Change-Id: Iff3a1f2f641a46ab9a0326579af3649f0c76fc65
2018-02-16 14:52:38 -08:00
David Srbecky
4015ef411a Adjust DEX file reading to follow layout changes in ART.
I have changed the root DEX debug descriptor in ART to more
closely follow the JIT debug descriptor. Add the appropriate
offsets to correctly fetch the linked list head for DEX files.

Test: testrunner.py -t 137
Test: libunwindstack_test
Change-Id: I90402befc88fec42658f7330d51ee79756a7f872
2018-02-16 14:54:49 +00:00
Christopher Ferris
beae42bc7f Fix soname reading code.
The dynamic section contained an address, not an offset into the elf
file to indicate where the soname exists. Changed to use the strtab
entries in the section headers to map this address to the actual offset.

Refactor the soname test a bit to make it easier to verify the code.

Bug: 73499044

Test: Passes new unit tests.
Test: Ran unwind_info on the failing shared elf and verified the soinfo
Test: is correct.
Change-Id: I16ba148389bcb9aadd3566fb442dac27f89fe894
2018-02-15 17:57:13 -08:00
David Sehr
3a26c27252 Move libdexfile out of runtime
Move the files out of runtime, leaving unfortunate dependences still
there on runtime/base (for the moment).  Also separates the build logic
into two Android.bp files.

Bug: 22322814
Test: make -j 50 test-art-host
Change-Id: I54b06f035034e7564480cd5d4c33c4f62785682d
2018-02-14 17:42:59 +00:00
Christopher Ferris
559c7f2092 Implement new DEX PC lookup scheme.
GDB wasn't handling the old one gracefully.

- Create a RegsInfo structure that can be used to properly eval expression
  data.
- Remove the versions on Dwarf ops. It doesn't work the in the real world
  and doesn't add useful information.
- Fix dex pc frame number bug.

Test: testrunner.py -j40 --host --cdex-fast -t 137
Test: libunwindstack_test
Test: All unit tests pass.
Change-Id: Iac4fea651b81cb6087fd237a9a5027a352a49245
2018-02-13 16:45:38 -08:00
Christopher Ferris
e4df5f5ab5 Fix computation of pc.
Fix the case where a non-zero load bias or a non-zero elf offset causes
the pc to be set incorrectly.

Add unit tests for these cases.

Bug: 73172903

Test: Ran unit tests.
Test: Ran the unit tests from the simpleperf CL that detected the failure.
Change-Id: Id8802c00b34c66875edd4926a20c5fccd2bb7d72
2018-02-12 14:06:13 -08:00
Christopher Ferris
73a2508dc4 Merge "Fix off by 4 error handling eh_frame hdr." 2018-02-12 18:58:34 +00:00
Christopher Ferris
a8c397317d Clear dex pc to avoid duplicate frames.
Bug: 73228466

Test: Passes new unit tests, fails without change.
Change-Id: I3660bfd16cbf2d5cf96490ca7714bc5f97914884
2018-02-12 08:46:19 -08:00
Christopher Ferris
e37e2d05b1 Fix off by 4 error handling eh_frame hdr.
- Add a new tool that can dump the register information given a pc.
- Add a new offline unwinder test that fails without this change.
- Update unit tests.
- Refactor offline unwind tests to make it easier to add tests.

Bug: 73048324

Test: Passes new unit tests.
Test: Passes libbacktrace unit tests.
Test: Ran debuggerd -b on random processes.
Change-Id: If6c70a044299505c2274ae6888b35bf9ac34b74b
2018-02-10 17:11:23 -08:00
Christopher Ferris
53914165e4 Expose per arch headers.
Bug: 73013352

Test: Compiles.
Change-Id: Ic05660db7d7858a9857143ee5e58cdaddcf52a35
2018-02-08 19:29:08 -08:00
David Sehr
892e675a89 Remove dependency on -no_art variant
Remove an external dependency on a shim I used to protect against
renaming.

Bug: 22322814
Test: make -j 50
Change-Id: I7e6eaee7d82a1a42d4c37daa74803cefc7bb68ce
2018-02-07 15:19:22 -08:00
Christopher Ferris
e762f1f193 Check that dex pc is in a valid map.
Add new unit tests for dex pc being non-zero.

Bug: 73004673

Test: Ran unit tests.
Test: Ran art 137-cfi test on host for interpreter.
Change-Id: I09bbf96d0ed65fc1e5896e4ab2bc67867e3b7fdb
2018-02-06 15:00:04 -08:00
David Srbecky
d663ef9772 Merge "Fix in-memory loading of cdex files with shared data." 2018-02-06 11:00:31 +00:00
Christopher Ferris
5f5cb238f0 Small test clean up.
Shrink a few files that are huge by removing all of the .debug_XXX
sections except .debug_frame since they aren't used.

Rename all of the arm32 to arm and x86_32 to x86.

Test: All unit tests pass.
Change-Id: Ia0f0baadf2a7fbc42a544aff2f14d5ed5f9287b7
2018-02-05 13:12:54 -08:00
David Srbecky
417f7c3720 Fix in-memory loading of cdex files with shared data.
Several cdex files may share the same data for de-duplication.

Bug: 72520014
Test: Disable DexFileFromFile and then run ART's 137 test.
Change-Id: Icfe04255cc20a302f844c2e3e3016578856e1f82
2018-02-05 20:40:31 +00:00
Christopher Ferris
7747b60faa Load dex files from ART-specific data structure.
Fixes cdex which was recently changed to have shared data section,
which means the DEX PC cannot be used to find the right symbol,
as the bytecode is no longer within the dex file, and in-fact,
we might have to scan multiple dex files to find the method.

Bug: 72520014
Test: testrunner.py --host --cdex-none -t 137
Test: testrunner.py --host --cdex-fast -t 137
Test: All unit tests pass.
Change-Id: I80265d05ad69dd9cefbe3f8a75e4cd349002af5e
2018-02-02 15:03:00 -08:00
David Srbecky
f9006ec9b6 Fix symbol resolution within a dex file.
Fixes the ART 137-cfi test, currently failing on buildbot.

Test: testrunner.py -j40 --host --cdex-none -t 137 -b
Change-Id: I16a007b291702207bbd003fd1e78e8e5ced7cd68
2018-02-01 14:51:57 +00:00
Christopher Ferris
d70ea5ea85 Move dex pc frame creation into libunwindstack.
Test: Compiles, all unit tests pass.
Test: Ran 137-cfi art test in interpreter and verified interpreter
Test: frames still show up.

Change-Id: Icea90194986faa733a873e8cf467fc2513eb5573
2018-01-31 14:19:42 -08:00
Christopher Ferris
bb4d172f70 Merge "Add a global elf cache." 2018-01-26 14:55:15 +00:00
Christopher Ferris
0b79ae155f Add a global elf cache.
Bug: 65682279

Test: Ran new unit tests.
Change-Id: I19c64614b2b11a27f58204d4cc34913c02e04c36
2018-01-25 17:11:33 -08:00
Christopher Ferris
c85935de54 Remove DwarfError.h that moved.
I think a rebase recreated this file, so deleting this now.

Bug: 65682279

Test: Compiles.
Change-Id: I1f885ed6254089ef50f293b4c407b110f8c878da
2018-01-25 16:02:20 -08:00
Treehugger Robot
dc0edb586d Merge "Fix wrong mov instruction size." 2018-01-25 23:34:56 +00:00
Chih-Hung Hsieh
09f88076c8 Fix wrong mov instruction size.
* New clang 7.0 assembler rejects mov with wrong length.

Bug: 72412103
Test: build and boot in emulator
Change-Id: If1a1affaa4a149265f8cc2b8bf463e58e71cc47a
2018-01-25 11:44:19 -08:00
Christopher Ferris
2fcf4cf13e Add error propagation into Unwinder/Elf objects.
The backtrace offline code uses these error codes to diagnose errors.
In addtion, I've had cases where seeing these errors would help diagnose
failures.

This also allows us to add a few features to indicate why an unwind
terminated (such as max frames exceeded).

Bug: 65682279

Test: Updated unit tests pass.
Change-Id: If82b5092698e8a194016d670efff1320f9b44d50
2018-01-24 17:50:46 -08:00
Christopher Ferris
1a141a0925 Small behavioral changes to the unwinder.
- Be a little more lenient when reading the cies/fdes. If next entry data
  winds up incorrect, don't fail, simply stop processing the entries. This
  only applies when reading all of the cies/fdes at once.
- Fail to init an eh_frame with no entries and fallback to assuming the
  eh_frame has no header instead.
- Change the step to always try debug_frame first which has the most
  accurate information.
- Add small unit tests and a couple of offline unit tests to verify
  this behavior.

These changes are needed to support offline unwinding since it depends
on this new behavior.

Bug: 65682279

Test: Ran new unit tests.
Change-Id: I3529f1b0c8e14cd7409494e5de2f3c9e78d0855e
2018-01-24 13:20:03 -08:00
Christopher Ferris
98984b41da Add support for getting a dex pc.
Changes:
- Change the register type from int16_t to uint32_t for the location data
  and the Eval processing. This is because the special dex pc is > 65535.
- Add the ability for Dwarf register location information to point to a
  register that is itself a Dwarf location register.
- Add dex_pc to the frame information.
- Modify the unwind tool to print the dex pc if non-zero.

This does not implement the printing of the dex information in anything
but the unwind tool. It's not the final form of this printing.

Bug: 72070049

Test: Ran new unit tests.
Test: Dumped stack while in interpreter running 137-cfi art test and
Test: verified dex pc is set to non-zero.
Change-Id: I6ce8a6b577fb4f92abacbd433b1f68977e272542
2018-01-17 19:18:00 -08:00
Christopher Ferris
ed37aca987 Find first non-zero jit debug entry.
Sometimes a process will have multiple shared libraries loaded
that have defined __jit_debug_descriptor. Specifically, art testing
will load libart.so and libartd.so, which would have broken unwinding
through jit'd code for art testing if libart.so winds up being found first.
In order to avoid duplicating the code for the linker to figure out
which one is live, change the algorithm to find the first non-zero
first_entry_ set in __jit_debug_descriptor.

Bug: 68396769

Test: Passes unit tests.
Test: Verified this can unwind 137-cfi on arm/arm64.
Change-Id: Ic4d403065d2c6f22476ef0171e7add17cd1464cd
2018-01-16 14:59:51 -08:00
Christopher Ferris
150db124f3 Add ability to read jit gdb data.
Changes:
- New JitDebug class to handle all of the jit gdb interface.
- Add unit tests for all, along with new offline test using debug data.
- Add new Memory type called MemoryOfflineParts that has multiple
  MemoryOffline objects to support the offline test.
- Update the tools to use the JitDebug object.
- Modify libbacktrace to use the JitDebug, but only looking in libart.so
  and libartd.so.
- Change the Format32Bits to Is32Bit since it's more accurate and I use
  it in a different context where original name didn't make sense.
- Add a new function to find global variables in an elf file
  (GetGlobalVariable).
- Add a new function to determine if a pc is valid for this elf (IsValidPc).

Bug: 68396769

Test: Ran new unit tests. Added new offline test that uses jit debug data.
Test: Ran art test that generates jit data and verified a crash unwinds
Test: through the jit data.
Change-Id: I6e7ee2f5bab2242028a06feece156dff21c0a974
2018-01-12 11:18:42 -08:00
Christopher Ferris
3dfd2aea7a Add tool to save information from a process.
Also, modify the ProcessVmRead function to allow arbitrarily large
reads and add a test for it.

Test: Run tool and verify the output can be used to do an offline
Test: unwind.
Test: Ran unit tests.
Change-Id: I0974ddca4f5cf72b4c9fa29b597a0a669e223828
2017-12-20 12:57:01 -08:00
Treehugger Robot
8b18000b39 Merge "unwindstack: add some perfunctory MemoryOffline tests." 2017-12-18 22:21:45 +00:00
Josh Gao
f4a94c44b6 unwindstack: add some perfunctory MemoryOffline tests.
Add some tests for the behavior of MemoryOffline.

Test: libunwindstack_test 32/64 on hikey960
Change-Id: Ib65a0fe5347b86062ffeaf0adaf9af57066edb76
2017-12-15 14:11:12 -08:00
Christopher Ferris
e7b6624c3f Fix issues in libunwindstack.
- Add a load_bias field in MapInfo so that it can be loaded offline,
  and also so it can be cached.
- Add an Add function to the Maps class so that it's possible to manually
  create a map.
- Remove the OfflineMaps class since I haven't found a reason for this to
  exist.
- Add a pointer to the gnu debugdata compressed section in the interface
  itself and modify the step path to try eh_frame, then debug_frame, then
  gnu_debugdata. This way arm can add exidx as the last step behind
  gnu_debugdata. Add an offline test to verify the order of unwind.
- Fix x86_64_ucontext_t since it was a different size on 32 bit and 64 bit
  systems.

Test: Pass new unit tests.
Change-Id: I978b70d6c244bd307c62a29886d24c1a8cb2af23
2017-12-15 11:17:45 -08:00