342 Commits

Author SHA1 Message Date
zhijian
39772da5fd [AIX][XCOFF] address post-commit review comments of patch https://reviews.llvm.org/D82549
Summary:
Address post-commit review comments in the https://reviews.llvm.org/D82549, including

changed file name from llvm/test/tools/llvm-readobj/XCOFF/xcoff-auxiliary-header.test --> llvm/test/tools/llvm-readobj/XCOFF/auxiliary-header.test
replaced macro define by using lambda function.
added a helper function to reduce the duplicated check and print error code.

Reviewer : James Henderson
Differential Revision: https://reviews.llvm.org/D116220
2022-03-28 15:05:41 -04:00
Rainer Orth
42e391e4ca [ELF] Use SHF_SUNW_NODISCARD instead of SHF_GNU_RETAIN on Solaris
Instead of the GNU extension `SHF_GNU_RETAIN`, Solaris provides equivalent
functionality with `SHF_SUNW_NODISCARD`. This patch implements the necessary
support.

Tested on `sparcv9-sun-solaris2.11`, `amd64-pc-solaris2.11`, and
`x86_64-pc-linux-gnu`.

Differential Revision: https://reviews.llvm.org/D107955
2022-02-23 15:41:43 +01:00
esmeyi
b9d85a5231 [NFC][XCOFF] remove the tool name yaml2obj in the test. 2022-01-19 04:11:21 -05:00
esmeyi
05fffac1f9 [NFC][XCOFF] commit tests for D113552.
The code part of D113552 was committed at
817936408bad, where the test was left because
it depended on another patch.
There are no dependencies now.
2022-01-19 04:06:37 -05:00
Esme-Yi
ab97ffb96a Reland [XCOFF][yaml2obj] support for the auxiliary file header.
Summary: Fix the build failure on MSVC by making the `T` and `U` of the function
'T llvm::Optional<T>::getValueOr<llvm::yaml::Hex32>(U &&) const &' the same.

Differential Revision: https://reviews.llvm.org/D111487
2021-11-10 07:23:56 +00:00
Simon Pilgrim
32a4a883f6 Revert rGe1eec7601b6988b35ae3cdc8d67cf3cf4e1361dd "[XCOFF][yaml2obj] support for the auxiliary file header."
This is failing on MSVC builds: https://lab.llvm.org/buildbot/#/builders/86/builds/23436
2021-11-09 11:02:13 +00:00
Esme-Yi
e1eec7601b [XCOFF][yaml2obj] support for the auxiliary file header.
Summary:
  This patch adds yaml2obj supporting for the auxiliary
  file header of XCOFF.

Reviewed By: DiggerLin, jhenderson

Differential Revision: https://reviews.llvm.org/D111487
2021-11-09 09:48:40 +00:00
Kai Nacke
b050564d3e [AIX] Ignore case when comparing output from od
POSIX does not define the exact output from od tool.
While most implementations use lower case characters in hex output,
the z/OS USS implementation uses upper case characters.
To avoid LIT failures, the FileCheck option to ignore the case must
be used when checking hex bytes.

Reviewed By: abhina.sreeskantharajan

Differential Revision: https://reviews.llvm.org/D111427
2021-10-14 13:51:02 -04:00
Esme-Yi
b98c3e957f [yaml2obj][XCOFF] add the SectionIndex field for symbol.
Summary: Add the SectionIndex field for symbol.
1: a symbol can reference a section by SectionName or SectionIndex.
2: a symbol can reference a section by both SectionName and SectionIndex.
3: if both Section and SectionIndex are specified, but the two values refer
   to different sections, an error will be reported.
4: an invalid SectionIndex is allowed.
5: if a symbol references a non-existent section by SectionName, an error will be reported.

Reviewed By: jhenderson, Higuoxing

Differential Revision: https://reviews.llvm.org/D109566
2021-09-14 06:18:03 +00:00
Esme-Yi
909f3d7380 [yaml2obj][XCOFF] customize the string table
Summary: The patch adds support for yaml2obj customizing the string table.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D107421
2021-09-13 09:24:38 +00:00
Alfonso Sánchez-Beato
b33fd31772 [yaml2obj][COFF] Allow variable number of directories
Allow variable number of directories, as allowed by the
specification. NumberOfRvaAndSize will default to 16 if not specified,
as in the past.

Reviewed by: jhenderson

Differential Revision: https://reviews.llvm.org/D108825
2021-09-09 11:16:56 +01:00
Esme-Yi
f49c3a6882 [llvm-readobj][XCOFF] Print the length of the string table.
Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D107333
2021-08-09 06:47:15 +00:00
Esme-Yi
69396896fb [llvm-readobj][XCOFF] Fix the error dumping for the first
item of StringTable.

Summary: For the string table in XCOFF, the first 4 bytes
contains the length of the string table, so we should
print the string entries from fifth bytes. This patch
also adds tests for llvm-readobj dumping the string
table.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D105522
2021-08-03 09:08:58 +00:00
Esme-Yi
8011fc1953 [yaml2obj] Enable support for parsing 64-bit XCOFF.
Summary: Add support for yaml2obj to parse 64-bit XCOFF.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D100375
2021-07-30 02:06:04 +00:00
Fangrui Song
aa3df8ddcd [test] Avoid llvm-readelf/llvm-readobj one-dash long options and deprecated aliases (e.g. --file-headers) 2021-07-15 10:26:21 -07:00
Fangrui Song
46580d43fc [llvm-readobj] Switch command line parsing from llvm::cl to OptTable
Users should generally observe no difference as long as they don't use
unintended option forms. Behavior changes:

* `-t=d` is removed. Use `-t d` instead.
* `--demangle=false` and `--demangle=0` cannot be used. Omit the option or use `--no-demangle`. Other flag-style options don't have `--no-` forms.
* `--help-list` is removed. This is a `cl::` specific option.
* llvm-readobj now supports grouped short options as well.
* `--color` is removed. This is generally not useful (only apply to errors/warnings) but was inherited from Support.

Some adjustment to the canonical forms
(usually from GNU readelf; currently llvm-readobj has too many redundant aliases):

* --dyn-syms is canonical. --dyn-symbols is a hidden alias
* --file-header is canonical. --file-headers is a hidden alias
* --histogram is canonical. --elf-hash-histogram is a hidden alias
* --relocs is canonical. --relocations is a hidden alias
* --section-groups is canonical. --elf-section-groups is a hidden alias

OptTable avoids global option collision if we decide to support multiplexing for binary utilities.

* Most one-dash long options are still supported. `-dt, -sd, -st, -sr` are dropped due to their conflict with grouped short options.
* `--section-mapping=false` (D57365) is strange but is kept for now.
* Many `cl::opt` variables were unnecessarily external. I added `static` whenever appropriate.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D105532
2021-07-12 10:14:42 -07:00
Esme-Yi
0dad3f6ee2 [llvm-readobj][XCOFF] Add support for printing the String Table.
Summary: The patch adds the StringTable dumping to
llvm-readobj. Currently only XCOFF is supported.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D104613
2021-07-05 04:16:58 +00:00
Fangrui Song
d4dcb55c70 [llvm-readobj] Make -s and -t match llvm-readelf
llvm-readobj is an internal testing tool for binary formats. Its output and
command line options do not need to be stable. It isn't supposed to be part of a
build process.

llvm-readelf was created as a user-facing utility and its interface intends to
be compatible with GNU readelf (unless there are good reasons not to).

The two tools have mostly compatible options. -s and -t are noticeable
exceptions due to history. I think the cost of keeping the inconsistency
overweighs the little history-compatible benefit and hinders transition from
cl::opt to OptTable, so let's change it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D105055
2021-06-29 11:56:26 -07:00
Alexander Yermolovich
a224c5199b [LLD][LLVM] CG Graph profile using relocations
Currently when .llvm.call-graph-profile is created by llvm it explicitly encodes the symbol indices. This section is basically a black box for post processing tools. For example, if we run strip -s on the object files the symbol table changes, but indices in that section do not. In non-visible behavior indices point to wrong symbols. The visible behavior indices point outside of Symbol table: "invalid symbol index".

This patch changes the format by using R_*_NONE relocations to indicate the from/to symbols. The Frequency (Weight) will still be in the .llvm.call-graph-profile, but symbol information will be in relocation section. In LLD information from both sections is used to reconstruct call graph profile. Relocations themselves will never be applied.

With this approach post processing tools that handle relocations correctly work for this section also. Tools can add/remove symbols and as long as they handle relocation sections with this approach information stays correct.

Doing a quick experiment with clang-13.
The size went up from 107KB to 322KB, aggregate of all the input sections. Size of clang-13 binary is ~118MB. For users of -fprofile-use/-fprofile-sample-use the size of object files will go up slightly, it will not impact final binary size.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D104080
2021-06-24 09:09:33 -07:00
Esme-Yi
657aa3a763 [yaml2obj] Add support for writing the long symbol name.
Summary: This patch, as a follow-up of D95505, adds
support for writing the long symbol name by implementing
the StringTable. Only XCOFF32 is suppoted now.

Reviewed By: jhenderson, shchenz

Differential Revision: https://reviews.llvm.org/D103455
2021-06-21 05:09:56 +00:00
James Henderson
5c1639fe06 [yaml2obj][obj2yaml] Support custom ELF section header string table name
This patch adds support for a new field in the FileHeader, which states
the name to use for the section header string table. This also allows
combining the string table with another string table in the object, e.g.
the symbol name string table. The field is optional. By default,
.shstrtab will continue to be used.

This partially fixes https://bugs.llvm.org/show_bug.cgi?id=50506.

Reviewed by: Higuoxing

Differential Revision: https://reviews.llvm.org/D104035
2021-06-16 10:02:23 +01:00
James Henderson
fef3bfb1b2 [yaml2obj] Fix bug when referencing items in SectionHeaderTable
There was an off-by-one error caused by an index (which included an
index for the null section header) being used to check against the size
of a list of sections (which didn't include the null section header).

This is a partial fix for https://bugs.llvm.org/show_bug.cgi?id=50506.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D104098
2021-06-16 10:02:22 +01:00
Esme-Yi
50bb1b930d [yaml2obj] Initial the support of yaml2obj for 32-bit XCOFF.
Summary: The patch implements the mapping of the Yaml
information to XCOFF object file to enable the yaml2obj
tool for XCOFF. Currently only 32-bit is supported.

Reviewed By: jhenderson, shchenz

Differential Revision: https://reviews.llvm.org/D95505
2021-06-07 04:14:44 +00:00
Abhina Sreeskantharajan
c52fe0b021 [test] Use host platform specific error message substitution in lit tests
This patch uses the errno python library to print out the correct error messages instead of hardcoding the error message per platform.

Reviewed By: jhenderson, ASDenysPetrov

Differential Revision: https://reviews.llvm.org/D97472
2021-03-05 07:21:53 -05:00
Rahman Lavaee
0252e6ead1 [obj2yaml,yaml2obj] Add NumBlocks to the BBAddrMapEntry yaml field.
As discussed in D95511, this allows us to encode invalid BBAddrMap
sections to be used in more rigorous testing.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D96831
2021-02-17 15:45:13 -08:00
Alex Richardson
d613d8eb0e [yaml2obj] Handle NT_* string values in for ELF note types
This is required for D74393.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95953
2021-02-09 16:59:22 +00:00
Abhina Sreeskantharajan
e59d336e75 [test] Use host platform specific error message substitution in lit tests - continued
On z/OS, other error messages are not matched correctly in lit tests.

```
EDC5121I Invalid argument.
EDC5111I Permission denied.
```

This patch adds a lit substitution to fix it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95808
2021-02-03 09:53:22 -05:00
Abhina Sreeskantharajan
42a21778f6 [test] Use host platform specific error message substitution in lit tests
On z/OS, the following error message is not matched correctly in lit tests.

```
EDC5129I No such file or directory.
```

This patch uses a lit config substitution to check for platform specific error messages.

Reviewed By: muiez, jhenderson

Differential Revision: https://reviews.llvm.org/D95246
2021-01-29 07:16:30 -05:00
Georgii Rymar
68195b15a3 [yaml2obj] - Allow empty SectionHeaderTable definitions.
Currently we don't allow the following definition:

```
Sections:
  - Type: SectionHeaderTable
  - Name: .foo
    Type: SHT_PROGBITS
```

We report an error: "SectionHeaderTable can't be empty. Use 'NoHeaders' key to drop the section header table".

It was implemented in this way earlier, when `SectionHeaderTable`
was a dedicated key outside of the `Sections` list. And we did not
allow to select where the table is written.

Currently it makes sense to allow it, because a user might
want to place the default section header table at an arbitrary position,
e.g. before other sections. In this case it is not convenient and error prone
to require specifying all sections:

```
Sections:
  - Type: SectionHeaderTable
    Sections:
      - Name: .foo
      - Name: .strtab
      - Name: .shstrtab
  - Name: .foo
    Type: SHT_PROGBITS
```

This patch allows empty SectionHeaderTable definitions.

Differential revision: https://reviews.llvm.org/D95341
2021-01-28 10:51:52 +03:00
Abhina Sreeskantharajan
978444d531 Revert "[SystemZ][z/OS] Fix No such file or directory expression error"
This reverts commit 06f8a49693957bc27b83e0ab5f429ff874941a07.
2021-01-25 08:29:38 -05:00
Georgii Rymar
9c89dcf807 [yaml2obj, obj2yaml] - Implement section header table as a special Chunk.
This was discussed in D93678 thread.
Currently we have one special chunk - Fill.

This patch re implements the "SectionHeaderTable" key to become a special chunk too.
With that we are able to place the section header table at any location,
just like we place sections.

Differential revision: https://reviews.llvm.org/D95140
2021-01-25 13:08:08 +03:00
Georgii Rymar
51f4958057 [yaml2obj/obj2yaml] - Improve dumping/creating of ELF versioning sections.
This makes the following improvements.

For `SHT_GNU_versym`:
 * yaml2obj: set `sh_link` to index of `.dynsym` section automatically.
For `SHT_GNU_verdef`:
 * yaml2obj: set `sh_link` to index of `.dynstr` section automatically.
 * yaml2obj: set `sh_info` field automatically.
 * obj2yaml: don't dump the `Info` field when its value matches the number of version definitions.
For `SHT_GNU_verneed`:
 * yaml2obj: set `sh_link` to index of `.dynstr` section automatically.
 * yaml2obj: set `sh_info` field automatically.
 * obj2yaml: don't dump the `Info` field when its value matches the number of version dependencies.

Also, simplifies few test cases.

Differential revision: https://reviews.llvm.org/D94956
2021-01-21 10:36:48 +03:00
Abhina Sreeskantharajan
689aaba7ac [SystemZ][z/OS] Fix No such file or directory expression error matching in lit tests
On z/OS, the following error message is not matched correctly in lit tests. This patch updates the CHECK expression to match successfully.
```
EDC5129I No such file or directory.
```

Reviewed By: muiez

Differential Revision: https://reviews.llvm.org/D94239
2021-01-18 07:14:37 -05:00
Georgii Rymar
d9afe8588e [yaml2obj/obj2yaml] - Refine handling of SHT_GNU_verdef sections.
This patch:
1) Makes `Version`, `Flags`, `VersionNdx` and `Hash` fields to be `Optional<>`.
2) Disallows dumping version definitions that have `vd_version != 1`.
   `vd_version` identifies the version of the structure itself.
   (https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html,
    https://docs.oracle.com/cd/E19683-01/816-7777/chapter6-80869/index.html)
3) Stops dumping default values for `Version`, `Flags`, `VersionNdx` and `Hash` fields.
4) Refines testing.

Differential revision: https://reviews.llvm.org/D94659
2021-01-15 12:40:42 +03:00
Georgii Rymar
6d3098e7ff [obj2yaml,yaml2obj] - Refine how we set/dump the sh_entsize field.
This reuses the code from yaml2obj (moves it to ELFYAML.h).
With it we can set the `sh_entsize` in a single place in `obj2yaml`.

Note that it also fixes a bug of `yaml2obj`: we do not
set the `sh_entsize` field for the `SHT_ARM_EXIDX` section properly.

Differential revision: https://reviews.llvm.org/D93858
2021-01-13 11:52:40 +03:00
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
60df7c08b1 [obj2yaml,yaml2obj] - Fix issues with creating/dumping group sections.
We have the following issues related to group sections:
1) yaml2obj is unable to set the custom `sh_entsize` value, because the `EntSize`
   key is currently ignored.
2) obj2yaml is unable to dump the group section which `sh_entsize != 4`.
3) obj2yaml always dumps the "EntSize" for group sections, though
   usually we are trying to omit dumping default values when dumping keys.
   I.e. we should not print the "EntSize" key when `sh_entsize` == 4.

This patch fixes (1),(3) and adds the test case to document the behavior of (2).

Differential revision: https://reviews.llvm.org/D93854
2021-01-12 14:07:42 +03:00
Georgii Rymar
8590b5ccd5 [libObject, llvm-readobj] - Reimplement ELFFile<ELFT>::getEntry.
Currently, `ELFFile<ELFT>::getEntry` does not check an index of
an entry. Because of that the code might read past the end of the symbol
table silently. I've added a test to `llvm-readobj\ELF\relocations.test`
to demonstrate the possible issue. Also, I've added a unit test for
this method.

After this change, `getEntry` stops reporting the section index and
reuses the `getSectionContentsAsArray` method, which already has
all the validation needed. Our related warnings now provide
more and better context sometimes.

Differential revision: https://reviews.llvm.org/D93209
2020-12-18 16:52:27 +03:00
Georgii Rymar
8c2cf89834 [yaml2obj/obj2yaml] - Make Value/Size fields of Symbol optional.
When a field is optional we can use the `=<none>` syntax in macros.
This patch makes `Value`/`Size` fields of `Symbol` optional
and adds test cases for them.

Differential revision: https://reviews.llvm.org/D93010
2020-12-16 13:49:57 +03:00
Georgii Rymar
98a4289810 [llvm-readobj] - For SHT_REL relocations, don't display an addend.
This is https://bugs.llvm.org/show_bug.cgi?id=44257.

In LLVM style we always print `0` as addend when dumping
SHT_REL relocations. It is confusing, this patch stops
printing it as the first comment on the bug page suggests.

Differential revision: https://reviews.llvm.org/D93033
2020-12-14 12:03:00 +03:00
Georgii Rymar
7ac06444b8 [yaml2obj,obj2yaml] - Make Symbol::Section field optional.
This is similar to what we did earlier for fields of the Section class.

When a field is optional we can use the =<none> syntax in macros.

This was splitted from D92478.

Differential revision: https://reviews.llvm.org/D92565
2020-12-04 13:45:47 +03:00
Georgii Rymar
9aa7898200 Reland "[lib/Support/YAMLTraits] - Don't print leading zeroes when dumping Hex8/Hex16/Hex32 types." (https://reviews.llvm.org/D90930).
This reverts reverting commit fc40a03323a4b265ccbed34a07e281b13c5e8367
and fixes LLD (MachO/wasm) tests that failed previously.
2020-11-18 13:08:46 +03:00
Georgii Rymar
fc40a03323 Revert "[lib/Support/YAMLTraits] - Don't print leading zeroes when dumping Hex8/Hex16/Hex32 types."
This reverts commit 65fd17c241e22e1671e81efdb683687369c2feb3.

It breaks LLD/MachO tests that seems use obj2yaml the check the output.
2020-11-18 11:55:03 +03:00
Georgii Rymar
65fd17c241 [lib/Support/YAMLTraits] - Don't print leading zeroes when dumping Hex8/Hex16/Hex32 types.
When we produce an YAML output, we also print leading zeroes currently.
An output might look like this:

```
- Name:    .dynsym
  Type:    SHT_DYNSYM
  Address: 0x0000000000001000
  EntSize: 0x0000000000000018
```

There are probably no reason to print leading zeroes.
It just makes harder to read values. This patch stops printing them.
The output becomes like:

```
- Name:    .dynsym
  Type:    SHT_DYNSYM
  Address: 0x1000
  EntSize: 0x18
```

This affects obj2yaml mostly, but also dsymutil and llvm-xray tools output.

Differential revision: https://reviews.llvm.org/D90930
2020-11-18 11:31:00 +03:00
Georgii Rymar
a7a447be0f [yaml2obj] - ProgramHeaders: introduce FirstSec/LastSec instead of Sections list.
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.

To put them into segment we can do (1*):

```
Sections:
 - Section: foo1
 - Section: foo4
```

or we can use (2*):

```
Sections:
 - Section: foo1
 - Section: foo3
 - Section: foo4
```

or (3*) :

```
Sections:
 - Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
 - Section: (index 2)
 - Section: foo3
 - Section: foo4
```

It looks really confusing that we don't have to list all of sections.

At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).

This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.

Differential revision: https://reviews.llvm.org/D90458
2020-11-09 13:00:50 +03:00
Georgii Rymar
99a6401acc Recommit: [llvm-readelf/obj] - Allow dumping of ELF header even if some elements are corrupt.
This is recommit for D90903 with fixes for BB:
1) Used std::move<> when returning Expected<> (http://lab.llvm.org:8011/#/builders/112/builds/913)
2) Fixed the name of temporarily file in the file-headers.test (http://lab.llvm.org:8011/#/builders/36/builds/1269)
   (a local old temporarily file was used before)

For creating `ELFObjectFile` instances we have the factory method
`ELFObjectFile<ELFT>::create(MemoryBufferRef Object)`.

The problem of this method is that it scans the section header to locate some sections.
When a file is truncated or has broken fields in the ELF header, this approach does
not allow us to create the `ELFObjectFile` and dump the ELF header.

This is https://bugs.llvm.org/show_bug.cgi?id=40804

This patch suggests a solution - it allows to delay scaning sections in the
`ELFObjectFile<ELFT>::create`. It now allows user code to call an object
initialization (`initContent()`) later. With that it is possible,
for example, for dumpers just to dump the file header and exit.
By default initialization is still performed as before, what helps to keep
the logic of existent callers untouched.

I've experimented with different approaches when worked on this patch.
I think this approach is better than doing initialization of sections (i.e. scan of them)
on demand, because normally users of `ELFObjectFile` API expect to work with a valid object.
In most cases when a section header table can't be read (because of an error), we don't
have to continue to work with object. So we probably don't need to implement a more complex API.

Differential revision: https://reviews.llvm.org/D90903
2020-11-09 12:53:53 +03:00
Georgii Rymar
f59216b58f Revert "[llvm-readelf/obj] - Allow dumping of ELF header even if some elements are corrupt."
This reverts commit ea8a0b8b29eb08d3f0f6ac40942a2d8e98ab57ee.

It broke BBots.
http://lab.llvm.org:8011/#/builders/14/builds/1439
http://lab.llvm.org:8011/#/builders/112/builds/913
2020-11-09 11:50:50 +03:00
Georgii Rymar
ea8a0b8b29 [llvm-readelf/obj] - Allow dumping of ELF header even if some elements are corrupt.
For creating `ELFObjectFile` instances we have the factory method
`ELFObjectFile<ELFT>::create(MemoryBufferRef Object)`.

The problem of this method is that it scans the section header to locate some sections.
When a file is truncated or has broken fields in the ELF header, this approach does
not allow us to create the `ELFObjectFile` and dump the ELF header.

This is https://bugs.llvm.org/show_bug.cgi?id=40804

This patch suggests a solution - it allows to delay scaning sections in the
`ELFObjectFile<ELFT>::create`. It now allows user code to call an object
initialization (`initContent()`) later. With that it is possible,
for example, for dumpers just to dump the file header and exit.
By default initialization is still performed as before, what helps to keep
the logic of existent callers untouched.

I've experimented with different approaches when worked on this patch.
I think this approach is better than doing initialization of sections (i.e. scan of them)
on demand, because normally users of `ELFObjectFile` API expect to work with a valid object.
In most cases when a section header table can't be read (because of an error), we don't
have to continue to work with object. So we probably don't need to implement a more complex API.

Differential revision: https://reviews.llvm.org/D90903
2020-11-09 11:27:07 +03:00
Rahman Lavaee
82e7c4ce45 [obj2yaml] [yaml2obj] Add yaml support for SHT_LLVM_BB_ADDR_MAP section.
YAML support allows us to better test the feature in the subsequent patches. The implementation is quite similar to the .stack_sizes section.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D88717
2020-11-06 12:44:42 -08:00
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