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8 commits

Author SHA1 Message Date
Christopher Ferris
4cc36d2b43 Fix handling of load bias values.
It turns out that for the dwarf information, if a FDE indicates it's pc
relative, then pc has to be incremented by the load bias. If not, then
it should not be incremented.

Previously, the code always subtracted load bias values from pcs, and assumed
that all fdes were incremented by load bias values. The new code actually
reads the fdes and adjusted the pcs in the fde and in the eh frame hdr so
that load bias values are already handled properly.

In addition, add dumping of arm exidx values in unwind_reg_info. This allowed
verifying that the debug frame in those elf files was being handled properly.

Added a new unit test that only has a debug frame that has a non-zero load
bias and has fde entries that do not have pc relative encoding.

Fix a couple of other small bugs.

Bug: 109824792

Test: All libbacktrace/libunwindstack unit tests pass.
Test: Ran ART 137-cfi test and 004-ThreadStress.
Test: Verify that displaying the fde start and end pc actually match the
Test: real data for fde that have pc relative set, and that don't.
Test: Verified that the unwind information for arm exidx matches the
Test: debug frame data.

Change-Id: I707555286b5cb05df9f25489e8c5ede753cfe0fb
2018-06-11 18:53:55 -07:00
Christopher Ferris
53914165e4 Expose per arch headers.
Bug: 73013352

Test: Compiles.
Change-Id: Ic05660db7d7858a9857143ee5e58cdaddcf52a35
2018-02-08 19:29:08 -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
d06001d6e0 Split arch data into separate files.
Add an ArchEnum to express the arch of the Elf objects and Reg objects.

Split out the regs code into per arch pieces and generic parts.
Also, split out the header files for each arch.

Do not break out the test code yet, there isn't enough and it doesn't
help to maintain the tests.

Test: libunwindstack/libbacktrace/debuggerd unit tests pass.
Test: Running debuggerd -b <PIDS> yields valid data on bullhead.
Change-Id: If61f6c730c9ff2249f986b41de8c4d62f7158325
2017-12-06 16:01:40 -08:00
Christopher Ferris
d226a51409 Make the library usable as a library.
- Add namespace unwindstack everywhere so that it's easier for other
  code to use the library.
- Move some of the header files into include/unwindstack so that they
  can be exposed.
- Modify the headers so that only a limited number need to be exposed.
- Update the tools to use the new headers.
- Add a GetLoadBias() call on the Elf object. This prevents the need
  to get the interface object out of the Elf object.
- Move the GetRelPc() call out of the Reg class, to the Elf class. It's
  not always the case that a Reg object will be around when you want to
  get a relative pc. The tests for this moved to ElfTest.cpp.

Bug: 23762183

Test: Unit tests pass.
Change-Id: Iac609dac1dd90ed83d1a1e24ff2579c96c023bc3
2017-07-14 12:20:23 -07:00
Christopher Ferris
9416703f5b Remove assert, use CHECK instead.
- Use the CHECK macro everywhere that assert was used.
- Remove the _debug version of the tests and leave the CHECK macro so
  it's always checking in the code.

Bug: 23762183

Test: Ran unit tests.
Change-Id: Ie705eedae393d0e95bb9d99f852687a11881aef1
2017-06-29 10:29:43 -07:00
Christopher Ferris
3958f8060a Elf interface for new unwinder.
This cl includes the code to read arm unwind information from a shared
library.

Bug: 23762183

Test: Passes all unit tests. I can dump the arm unwind information
Test: for an arm shared library.
Change-Id: I43501ea2eab843b81de8bd5128401dd1971af8d3
2017-03-09 12:27:16 -08:00
Christopher Ferris
723cf9b6e6 New version of unwinder.
Bug: 23762183

Test: All unit tests pass.
Change-Id: I0ac69e55af56e1142c0a1ee3715cdc48f2ed3ec3
2017-01-25 12:21:51 -08:00