Commit Graph

13 Commits

Author SHA1 Message Date
Georgii Rymar 141906fa14 [llvm-readelf/obj] - Add support of multiple SHT_SYMTAB_SHNDX sections.
Currently we don't support multiple SHT_SYMTAB_SHNDX sections
and the DT_SYMTAB_SHNDX tag currently.

This patch implements it and fixes the
https://bugs.llvm.org/show_bug.cgi?id=43991.

I had to introduce the `struct DataRegion` to ELF.h,
it is used to represent a region that might have no known size.
It is needed, because we don't know the size of the extended
section indices table when it is located via DT_SYMTAB_SHNDX.
In this case we still want to validate that we don't read
past the end of the file.

Differential revision: https://reviews.llvm.org/D92923
2021-01-13 11:36:43 +03:00
Georgii Rymar 3d811c57aa [llvm-readelf/obj] - Stop calling `reportError` in `printArchSpecificInfo()`.
This is related to MIPS. Currently we might report an error and exit,
though there is no problem to report a warning and try to continue dumping
an object. The code uses `MipsGOTParser<ELFT> Parser`, which is isolated
in this method.

Differential revision: https://reviews.llvm.org/D92090
2020-11-27 10:27:00 +03:00
Georgii Rymar f1ceaa200f [llvm-readobj/elf][test] - Stop using precompiled binaries in mips-got.test
This removed 2 last precompiled binaries from the mips-got.test.
YAML descriptions are used instead.

Differential revision: https://reviews.llvm.org/D88565
2020-10-06 12:04:44 +03:00
Georgii Rymar 0767a0b53e [llvm-readobj][test] - Stop using few precompiled binaries in mips-got.test
This removes 4 input files (one source file and 3 precompiled binaries) from
`mips-got.test` (now YAMLs are used instead) and also makes the testing of
the GNU output a bit stricter (`--strict-whitespace --match-full-lines`).

Differential revision: https://reviews.llvm.org/D88488
2020-09-30 11:48:01 +03:00
Georgii Rymar bd99fb4e0b [llvm-readelf/obj] - Fix extended section symbol indices printed in warnings for MIPS GOT/PLT entries.
Recent refactoring introduced a symbol index argument for `getFullSymbolName` method,
which is only used for reporting error messages about invalid extended symbol indexes.

There are few issues in the implementation and we don't report correct symbol indices
when dumping MIPS GOT/PLT entries currently.

This patch adds test cases and fixes the issue.

Differential revision: https://reviews.llvm.org/D88089
2020-09-23 13:42:56 +03:00
Georgii Rymar 095f6fbbd7 [llvm-readelf/obj] - Stop printing invalid names for unnamed section symbols.
We have an issue with `ELFDumper<ELFT>::getSymbolSectionName`:
1) It is used deeply for both LLVM/GNU styles and might return LLVM-style only
   values to describe symbols: "Undefined", "Processor Specific", "Absolute", etc.

2) `getSymbolSectionName` is used by `getFullSymbolName` and these special values
   might appear instead of symbol names in many places.
   This occurs for unnamed section symbols currently.

This patch extracts the LLVM specific logic to `LLVMStyle<ELFT>::printSymbolSection`,
which seems to be the only place where we want to print the special values mentioned.
It also adds a meaningful new warning that is reported when we are unable to get
a section index for a section symbol.

Differential revision: https://reviews.llvm.org/D87764
2020-09-21 13:05:46 +03:00
Georgii Rymar 0dca1ac617 [llvm-readelf/obj][test] - Document what we print in various places for unnamed section symbols.
We have an issue with `ELFDumper<ELFT>::getSymbolSectionName`:
1) It is used deeply for both LLVM/GNU styles and might return LLVM-style only
   values to describe symbols: "Undefined", "Processor Specific", "Absolute", etc.

2) `getSymbolSectionName` is used by `getFullSymbolName` and these special values
   might appear in instead of symbol names in many places.
   This occurs for unnamed section symbols.

It was not noticed because for most cases I've found it is unexpected to have an
unnamed section symbol. This patch documents the existent behavior, adds tests and FIXMEs.

Differential revision: https://reviews.llvm.org/D87763
2020-09-17 15:56:51 +03:00
Georgii Rymar b475eca1ed [llvm-readobj/elf] - Merge mips-got-overlapped.test to mips-got.test and refine testing.
The `mips-got-overlapped.test` was introduced in D16968 and its intention is
to check that when there is an empty section at the same address as `.got`,
then we are able to locate `.got` and dump it.

The issue is that this test does not test llvm-readelf and uses a precompiled
object. This path starts using YAML instead and merges
mips-got-overlapped.test to mips-got.test.

Differential revision: https://reviews.llvm.org/D86080
2020-08-18 11:37:34 +03:00
Georgii Rymar 7e32797552 [llvm-readobj] - Don't call `unwrapOrErr` in `findSectionByName`.
We have a `findSectionByName` helper that tries to find a section
by it name. It is used in a few places, but never tested.

I'd like to reuse this helper for a different place.
For this, I've changed it to return Expected<> and now it
doesn't use `unwrapOrErr` anymore. It also now a member of
Dumper class and might report warnings.

Differential revision: https://reviews.llvm.org/D84651
2020-08-03 12:41:00 +03:00
Georgii Rymar 1f84ace3c7 [llvm-readobj] - Refine error reporting in MipsGOTParser<ELFT> helper.
This is a follow-up for D83225. This does the following:
1) Adds missing tests for existent errors.
2) Stops using `unwrapOrError` to propagate errors to caller.
   (I am trying to get rid of all `unwrapOrErr` calls in the llvm-readelf code).
3) Improves error messages reported slightly.

Differential revision: https://reviews.llvm.org/D83314
2020-07-08 12:05:52 +03:00
Georgii Rymar e7abed3d48 [llvm-readobj] - Refactor the MipsGOTParser<ELFT> to stop using report_fatal_error().
`MipsGOTParser` is a helper class that is used to dump MIPS GOT and PLT.
There is a problem with it: it might call report_fatal_error() on invalid input.
When this happens, the tool reports a crash:

```
# command stderr:
LLVM ERROR: Cannot find PLTGOT dynamic table tag.
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backt
race.
Stack dump:
...
```

Such error were not tested. In this patch I've refactored `MipsGOTParser`:

I've splitted handling of GOT and PLT to separate methods. This allows to propagate
any possible errors to caller and should allow to dump the PLT when something is wrong
with the GOT and vise versa in the future.

I've added tests for each `report_fatal_error()`
and now calling the `reportError` instead. In the future we might want to switch to
reporting warnings, but it requres the additional testing and should
be performed independently.

I've kept `unwrapOrError` calls untouched for now as I'd like to focus on eliminating
`report_fatal_error` calls in this patch only.

Differential revision: https://reviews.llvm.org/D83225
2020-07-07 16:43:38 +03:00
Georgii Rymar a256193afa [llvm-readobj] - Add prepending # to mips-got.test and mips-plt.test. NFC.
It was requested in D83225 review to do it separately.
2020-07-07 14:44:30 +03:00
Georgii Rymar dbf520f617 [llvm-readobj][test] - Move platform specific test cases and their inputs to separate folders.
This creates the next subfolders in the test directory:
"COFF", "ELF", "MachO", "wasm".

I've also removed platform specific prefixes, like "coff-*".
One unused binary was removed as well: `Inputs/relocs.obj.elf-mips`

Differential revision: https://reviews.llvm.org/D71203
2019-12-10 11:36:23 +03:00