Commit Graph

129 Commits

Author SHA1 Message Date
Rahman Lavaee c22d18b7e8 Read NumBlocks as uint64_t.
This fixes the Buildbot failure happened due to a sloppy merge.
2021-03-08 16:46:13 -08:00
Rahman Lavaee 9f52708660 [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
2021-02-22 18:08:26 -08:00
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
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
Georgii Rymar d5e48f1347 [yaml2obj][obj2yaml] - Improve how we set/dump the sh_entsize field.
We already set the `sh_entsize` field in a single place
for all non-implicit sections.

This patch reorders the logic slightly and with it
we finally have the only one place where the `sh_entsize` is set.

obj2yaml will not dump the `EntSize` key for `SHT_DYNSYM/SHT_SYMTAB` sections anymore,
when the value of `sh_entsize` is equal to `sizeof(Elf_Sym)`

Note that this also seems revealed an issue in llvm-objcopy:
Previously yaml2obj set the `sh_entsize` for the `.symtab` section to 0x18,
now we it sets it for `SHT_SYMTAB` sections, i.e. by type.
But the `llvm-objcopy/ELF/only-keep-debug.test` has a `.symtab` section of type `SHT_STRTAB`,
and now yaml2obj sets the `sh_entsize` to 0 for it.
I had to update the corresponding check lines for `ES`, but the behavior of
`llvm-objcopy` should be fixed instead I think.
I've added a TODO and a comment.

Differential revision: https://reviews.llvm.org/D95364
2021-01-26 13:33:02 +03:00
Georgii Rymar 029644ee51 [yaml2obj] - Refine how we set the sh_link field. NFCI.
This refactors the logic that sets the `sh_link` field.
With this patch we set it in a single place for all sections.

Differential revision: https://reviews.llvm.org/D95354
2021-01-26 12:20:57 +03:00
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
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 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 438bc157a4 [libObject] - Add more ELF types to LLVM_ELF_IMPORT_TYPES_ELFT define (ELFTypes.h).
This allows to get rid of lots for typedefs/usings from many places.

Differential revision: https://reviews.llvm.org/D93801
2020-12-25 11:39:05 +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 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 5edb90c927 [obj2yaml] - Dump section offsets in some cases.
Currently we never dump the `sh_offset` key.
Though it sometimes an important information.

To reduce the noise this patch implements the following logic:
1) The "Offset" key for the first section is always emitted.
2) If we can derive the offset for a next section naturally,
   then the "Offset" key is omitted.

By "naturally" I mean that section[X] offset is expected to be:
```
offsetOf(section[X]) == alignTo(section[X - 1].sh_offset + section[X - 1].sh_size, section[X].sh_addralign)
```

So, when it has the expected value, we omit it from the output.

Differential revision: https://reviews.llvm.org/D91152
2020-11-25 12:41:01 +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
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 5ffafa870c [yaml2obj] - Add support of Offset for .strtab/.shstrtab/.dynstr sections.
These sections are implicit and handled a bit differently.
Currently the "Offset" is ignored for them.
This patch fixes an issue.

Differential revision: https://reviews.llvm.org/D90446
2020-11-02 11:56:32 +03:00
Georgii Rymar 2bfaf19516 [yaml2obj] - Make `Section::Link` field to be `Optional<>`.
`Link` is not an optional field currently.
Because of this it is not convenient to write macros.

This makes it optional and fixes corresponding test cases.

Differential revision: https://reviews.llvm.org/D90390
2020-10-30 16:18:53 +03:00
Georgii Rymar fcf6287916 [yaml2obj] - Improve handling of SectionHeaderTable::NoHeaders flag.
When `NoHeaders` is set, we still have following issues:
1) We emit the `.shstrtab` implicit section of size 1 (empty string table).
2) We still align the start of the section header table, what affects the output size.
3) We still write section header table bytes.

This patch fixes all of these issues.

Differential revision: https://reviews.llvm.org/D90295
2020-10-29 12:16:52 +03:00
Georgii Rymar edfb2f8b23 [yaml2obj] - Support the "Offset" key for the .dynsym section.
Our "implicit" sections are handled separately from regular ones.
It turns out that the "Offset" key is not handled properly for them.

Perhaps we can generalize handling in one place, but before doing that I'd like
to add support and test cases for each implicit section.
(I need this particular single change to unblock another patch that is already on review,
and I guess doing it independently for each section will be cleaner, see below).

In this patch I've removed `explicit-dynsym-no-dynstr.yaml` to `dynsym-section.yaml`
and added the new test into. In a follow-up we probably might want
to merge 2 another existent `dynsymtab-*.yaml` tests into it too.

Differential revision: https://reviews.llvm.org/D90224
2020-10-28 14:22:29 +03:00
Georgii Rymar 2d59ed4e62 [yaml2obj] - Add a way to override the sh_addralign field of a section.
Imagine the following declaration of a section:
```
Sections:
  - Name:         .dynsym
    Type:         SHT_DYNSYM
    AddressAlign: 0x1111111111111111
```

The aligment is large and yaml2obj reports an error currently:
"the desired output size is greater than permitted. Use the --max-size option to change the limit"

This patch implements the "ShAddrAlign" key, which is similar to other "Sh*" keys we have.
With it it is possible to override the `sh_addralign` field, ignoring the writing of alignment bytes.

Differential revision: https://reviews.llvm.org/D90019
2020-10-27 13:03:38 +03:00
Georgii Rymar 3cfd9384bf [lib/ObjectYAML] - Simplify the code that handles Content/Size fields.
This is a follow-up for D89039 patch, which adds a support for
`Content`/`Size` for all sections.

Assuming that all of sections have a support of these 2 fields,
we can simplify and generalize the code.

Depends on D89039

Differential revision: https://reviews.llvm.org/D89120
2020-10-16 09:57:27 +03:00
Georgii Rymar d8bb30c551 [yaml2obj] - Allow specifying no tags to create empty sections in few cases.
Currently we have a few sections that
does not support specifying no keys for them. E.g. it is required that one
of "Content", "Size" or "Entries" key is present. There is no reason to
have this restriction. We can allow this and emit an empty section instead.

This opens road for a simplification and generalization of the code in `validate()`
that is discussed in the D89039 thread.

Depends on D89039.

Differential revision: https://reviews.llvm.org/D89391
2020-10-15 11:22:02 +03:00
Georgii Rymar 400103f3d5 [yaml2obj/obj2yaml] - Add support of 'Size' and 'Content' keys for all sections.
Many sections either do not have a support of `Size`/`Content` or support just a
one of them, e.g only `Content`.

`Section` is the base class for sections. This patch adds `Content` and `Size` members
to it and removes similar members from derived classes. This allows to cleanup and
generalize the code and adds a support of these keys for all sections (`SHT_MIPS_ABIFLAGS`
is a only exception, it requires unrelated specific changes to be done).

I had to update/add many tests to test the new functionality properly.

Differential revision: https://reviews.llvm.org/D89039
2020-10-15 11:11:41 +03:00
Georgii Rymar 82311766d9 [obj2yaml] - Rename `Group` to `GroupSection`. NFC.
The `Group` class represents a group section and it is
named inconsistently with other sections which all has
the "Section" suffix. It is sometimes confusing,
this patch addresses the issue.

Differential revision: https://reviews.llvm.org/D88892
2020-10-07 17:04:15 +03:00
Georgii Rymar 5829dc9250 [yaml2obj][elf2yaml] - Add a support for the `EntSize` field for `SHT_HASH` sections.
Specification  for SHT_HASH table says (https://refspecs.linuxbase.org/elf/gabi4+/ch5.dynamic.html#hash)
that it contains Elf32_Word entries for both 32/64 bit objects.

Currently both GNU linkers and LLD sets the `sh_entsize` field to `4`.

At the same time, `yaml2obj` ignores the `EntSize` field for SHT_HASH sections.
This patch fixes this and also adds a support for obj2yaml: it will not
dump this field when the `sh_entsize` contains the default value (`4`).

Differential revision: https://reviews.llvm.org/D88652
2020-10-02 12:01:50 +03:00
Georgii Rymar dab9917164 [yaml2obj][obj2yaml] - Add a support for SHT_ARM_EXIDX section.
This adds the support for SHT_ARM_EXIDX sections to obj2yaml/yaml2obj tools.

SHT_ARM_EXIDX is a ARM specific index table filled with entries.
Each entry consists of two 4-bytes values (words).
(https://developer.arm.com/documentation/ihi0038/c/?lang=en#index-table-entries)

Differential revision: https://reviews.llvm.org/D88228
2020-09-28 11:45:49 +03:00
Xing GUO 6d242a7326 Revert "[DWARFYAML] Add support for referencing different abbrev tables."
This reverts commit f7ff0ace96.

This change is causing build failure.

http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/10400
2020-08-21 12:15:54 +08:00
Xing GUO f7ff0ace96 [DWARFYAML] Add support for referencing different abbrev tables.
This patch adds support for referencing different abbrev tables. We use
'ID' to distinguish abbrev tables and use 'AbbrevTableID' to explicitly
assign an abbrev table to compilation units.

The syntax is:
```
debug_abbrev:
  - ID: 0
    Table:
      ...
  - ID: 1
    Table:
      ...
debug_info:
  - ...
    AbbrevTableID: 1 ## Reference the second abbrev table.
  - ...
    AbbrevTableID: 0 ## Reference the first abbrev table.
```

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D83116
2020-08-21 11:44:25 +08:00
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
Xing GUO 760e4f2202 [DWARFYAML] Add helper function getDWARFEmitterByName(). NFC.
In this patch, we add a helper function getDWARFEmitterByName(). This
function returns the proper DWARF section emitting method by the name.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D84952
2020-07-31 20:07:39 +08:00
Xing GUO cbf5bf513b [DWARFYAML] Add emitDebug[GNU]Pub[names/types] functions. NFC.
In this patch, emitDebugPubnames(), emitDebugPubtypes(),
emitDebugGNUPubnames(), emitDebugGNUPubtypes() are added.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D85003
2020-07-31 20:05:30 +08:00
Georgii Rymar bd93f5ce07 [yaml2obj] - Add a way to override sh_type section field.
This adds the `ShType` key similar to others `Sh*` keys we have.

My use case is the following. Imagine we have a `SHT_SYMTAB_SHNDX`
section and want to hide it from a dumper. The natural way would be to
do something like:

```
  - Name:    .symtab_shndx
    Type:    [[TYPE=SHT_SYMTAB_SHNDX]]
    Entries: [ 0, 1 ]

```

and then change the TYPE from `SHT_SYMTAB_SHNDX` to something else,
for example to `SHT_PROGBITS`.

But we have a problem: regular sections does not have `Entries` key,
so yaml2obj will be unable to produce a section.

The solution is to introduce a `ShType` key to override the final type.

This is not the first time I am facing the need to change the type. I
was able to invent workarounds or solved issues differently in the past,
but finally came to conclusion that we just should support the `ShType`.

Differential revision: https://reviews.llvm.org/D84738
2020-07-28 16:16:42 +03:00
Xing GUO b1731da871 [DWARFYAML] Rename getUsedSectionNames() to getNonEmptySectionNames().
This patch renames getUsedSectionNames() to getNonEmptySectionNames.
NFC.
2020-07-26 21:10:38 +08:00
Xing GUO 1ab3d6c819 [DWARFYAML] Implement the .debug_rnglists section.
This patch implements the .debug_rnglists section. We are able to
produce the .debug_rnglists section by the following syntax.

```
debug_rnglists:
  - Format:              DWARF32 ## Optional
    Length:              0x1234  ## Optional
    Version:             5       ## Optional
    AddressSize:         0x08    ## Optional
    SegmentSelectorSize: 0x00    ## Optional
    OffsetEntryCount:    2       ## Optional
    Offsets:             [1, 2]  ## Optional
    Lists:
      - Entries:
          - Operator: DW_RLE_base_address
            Values:   [ 0x1234 ]
```

The generated .debug_rnglists is verified by llvm-dwarfdump, except for
the operator DW_RLE_startx_endx, since llvm-dwarfdump doesn't support
it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D83624
2020-07-20 10:42:27 +08:00
Xing GUO 10478c9c64 [DWARFYAML] Implement the .debug_str_offsets section.
This patch helps add support for emitting the .debug_str_offsets section
to yaml2elf.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D83853
2020-07-16 22:33:13 +08:00
Georgii Rymar ed605b7b96 [yaml2obj] - Fix an issue with NoHeaders key.
When setting the NoHeaders to false,
the e_shnum field wasn't set correctly.

This patch fixes this bug.

Differential revision: https://reviews.llvm.org/D83941
2020-07-16 14:22:36 +03:00
Georgii Rymar 7a587ca932 [yaml2obj] - Rename FileHeader::SH* fields.
In D83482 we agreed to name e_* fields that are used for overriding
values (like e_phoff) as EPh* (e.g. EPhOff).

Currently we have a set of e_sh* fields that are named inconsistently
with this rule. This patch renames all of them.

Differential revision: https://reviews.llvm.org/D83766
2020-07-15 12:47:31 +03:00
Georgii Rymar 90e34b563a [yaml2obj] - Refine handling of the NoHeaders key.
Imagine we have an YAML description for some object and we want to
produce 2 outputs: with and without the section header.
A natural way to do it would look like:

```
--- !ELF
FileHeader:
  Class:   ELFCLASS64
  Data:    ELFDATA2LSB
  Type:    ET_REL
  Machine: EM_X86_64
Sections:
...
SectionHeaderTable:
  NoHeaders: [[NOHEADERS]]

```
But currently, we do not distinguish between no `NoHeaders` key case
and `NoHeaders == false`. Because of this we can't simply specify
`NOHEADERS = false`, as tool starts to complain.

With this patch the behavior changed. When we have:

```
SectionHeaderTable:
  NoHeaders: false

```
it is the same as we have no `SectionHeaderTable` at all.
(`NoHeaders` key still can't be used with `Sections/Excluded` keys)

Differential revision: https://reviews.llvm.org/D83672
2020-07-14 15:09:06 +03:00
Georgii Rymar 3001569323 [yaml2obj] - Add a syntax to override e_phoff, e_phentsize and e_phnum fields.
This adds `EPhOff`, `EPhEntSize` and `EPhNum` keys.
Will be useful for creating broken objects for testing llvm-readelf.

Differential revision: https://reviews.llvm.org/D83482
2020-07-14 13:16:19 +03:00
Xing GUO b954cb408f [ObjectYAML][ELF] Add support for emitting the .debug_gnu_pubnames/pubtypes sections.
This patch helps add support for emitting the .debug_gnu_pubnames and .debug_gnu_pubtypes sections.

The .debug_gnu_pub* sections is verified by llvm-dwarfdump.

Known issues:
- Doesn't support emitting multiple pub-tables.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D82367
2020-07-03 22:40:18 +08:00
Xing GUO fad54c50e4 [ObjectYAML][ELF] Add support for emitting the .debug_pubtypes section.
This patch helps add support for emitting the .debug_pubtypes section.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D82347
2020-06-24 00:01:07 +08:00
Xing GUO 8c7775e9a7 [ObjectYAML][ELF] Add support for emitting the .debug_pubnames section.
This patch helps add support for emitting the .debug_pubnames section to yaml2elf.

Known issues:
- Current implementation doesn't support emitting multiple sets of entries.
- Doesn't support DWARF64.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D82296
2020-06-23 20:40:33 +08:00
Xing GUO 1cfdda57fa [ObjectYAML][ELF] Add support for emitting the .debug_info section.
This patch helps add support for emitting the .debug_info section to yaml2elf.

Reviewed By: jhenderson, grimar, MaskRay

Differential Revision: https://reviews.llvm.org/D82073
2020-06-20 12:13:01 +08:00
Xing GUO 1f391afbf4 [ObjectYAML][ELF] Add support for emitting the .debug_abbrev section.
This patch enables yaml2elf emit the .debug_abbrev section.

The generated .debug_abbrev is verified using `llvm-dwarfdump`.

Known issues that will be addressed later:
- Current implementation doesn't support generating multiple abbreviation tables in one .debug_abbrev section.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D81820
2020-06-18 10:50:38 +08:00
Xing GUO 8aaeaddec8 [ObjectYAML][DWARF] Implement the .debug_addr section.
This patch implements the .debug_addr section.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D81541
2020-06-16 10:53:10 +08:00
Georgii Rymar ec4e68e667 [yaml2obj] - Introduce the "NoHeaders" key for "SectionHeaderTable"
We have an issue currently. The following YAML piece just ignores the `Excluded` key.

```
SectionHeaderTable:
  Sections: []
  Excluded:
    - Name: .foo
```

Currently the meaning is: exclude the whole table.

The code checks that the `Sections` key is empty and doesn't catch/check
invalid/duplicated/missed `Excluded` entries.

Also there is no way to exclude all sections except the first null section,
because `Sections: []` currently just excludes the whole the sections header table.

To fix it, I suggest a change of the behavior.

1) A new `NoHeaders` key is added. It provides an explicit syntax to drop the whole table.
2) The meaning of the following is changed:

```
SectionHeaderTable:
  Sections: []
  Excluded:
    - Name: .foo

```
Assuming there are 2 sections in the object (a null section and `.foo`), with this patch it
means: exclude the `.foo` section, keep the null section. The null section is an implicit
section and I think it is reasonable to make "Sections: []" to mean it is implicitly added.
It will be consistent with the global "Sections" tag that is used to describe sections.

3) `SectionHeaderTable->Sections` is now optional. No `Sections` is the same as
   `Sections: []` (I think it avoids a confusion).
4) Using of `NoHeaders` together with `Sections`/`Excluded` is not allowed.
5) It is possible to use the `Excluded` key without the `Sections` key now (in this case
   `Excluded` must contain all sections).
6) `SectionHeaderTable:` or `SectionHeaderTable: []` is not allowed.
7) When the `SectionHeaderTable` key is present, we still require all sections to be
   present in `Sections` and `Excluded` lists. No changes here, we are still strict.

Differential revision: https://reviews.llvm.org/D81655
2020-06-15 12:43:16 +03:00
Georgii Rymar 818ab3d654 [yaml2obj] - Allocate the file space for SHT_NOBITS sections in some cases.
This teaches yaml2obj to allocate file space for a no-bits section
when there is a non-nobits section in the same segment that follows it.

It was discussed in D78005 thread and matches GNU linkers and LLD behavior.

Differential revision: https://reviews.llvm.org/D80629
2020-06-11 12:54:53 +03:00
Georgii Rymar 3c123acf57 [yaml2obj] - Introduce a 10 Mb limit of the output by default and a --max-size option.
Multiple times we faced an issue of huge outputs due to unexpected behavior
or incorrect test cases. The last one was https://reviews.llvm.org/D80629#2073066.

This patch limits the output to 10 Mb for ELF and introduces the --max-size to change this
limit.

I've tried to keep the implementation non-intrusive.

The current logic we have is that we prepare section content in a buffer first and write
it to the output later. This patch checks the available limit on each writing attempt to this buffer
and stops writing when the limit is reached and raises the internal error flag.
Later, this flag is is checked before the actual writing to a file happens and
an error is reported.

Differential revision: https://reviews.llvm.org/D81258
2020-06-10 15:23:59 +03:00