Commit Graph

7 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 1af3cb5424 [llvm-readobj/libObject] - Allow dumping objects that has a broken SHT_SYMTAB_SHNDX section.
Currently it is impossible to create an instance of ELFObjectFile when the
SHT_SYMTAB_SHNDX can't be read. We error out when fail to parse the
SHT_SYMTAB_SHNDX section in the factory method.

This change delays reading of the SHT_SYMTAB_SHNDX section entries,
with it llvm-readobj is now able to work with such inputs.

Differential revision: https://reviews.llvm.org/D89379
2020-11-03 11:30:28 +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 a6436b0b3a [yaml2obj] - Make the 'Machine' key optional.
Currently we have to set 'Machine' to something in our
YAML descriptions. Usually we use 'EM_X86_64' for 64-bit targets
and 'EM_386' for 32-bit targets. At the same time, in fact, in most
cases our tests do not need a machine type and we can use
'EM_NONE'.

This is cleaner, because avoids the need of using a particular machine.

In this patch I've made the 'Machine' key optional (the default value,
when it is not specified is `EM_NONE`) and removed it (where possible)
from yaml2obj, obj2yaml and llvm-readobj tests.

There are few tests left where I decided not to remove it, because
I didn't want to touch CHECK lines or doing anything more complex
than a removing a "Machine: *" line and formatting lines around.

Differential revision: https://reviews.llvm.org/D86202
2020-08-20 11:40:51 +03:00
Fangrui Song 55c81d4282 [test] Use yaml2obj -o %t instead of > %t
To improve consistency and avoid unneeded shell feature (output
redirection).

While here, make other changes to improve consistency

--docnum 1 => --docnum=1
-docnum=x => --docnum=x
2020-01-21 17:20:18 -08:00
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