Commit Graph

107 Commits

Author SHA1 Message Date
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
Xing GUO 9728000395 [ObjectYAML][ELF] Add support for emitting the .debug_line section.
This patch enables yaml2elf emit the .debug_line section.

Test cases for emitting the dwarf64 .debug_line section and opcodes will be added later.

Known issues:
- We should replace `InitialLength` with `Format` and `Length`
- Currently implementation of the .debug_line section only fully supports DWARFv2, some header fields in DWARFv4 and DWARFv5 is missing, e.g., `header_length` in DWARFv4, `address_size` and `segment_selector_size` in DWARFv5.
- Some opcodes relies on the .debug_info section, we should warn user about it.

These issues will be addressed in a follow-up patch.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D81450
2020-06-09 23:42:40 +08:00
Xing GUO 9939f231e6 [ObjectYAML] Add support for error handling in DWARFYAML. NFC.
This patch intends to be an NFC-patch. Test cases will be added in a follow-up patch.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D81356
2020-06-08 22:49:29 +08:00
Xing GUO 67b4afc41a [DWARFYAML] Rename function names to match the coding style. NFC. 2020-06-08 17:31:02 +08:00
Xing GUO 288025494e [ObjectYAML][DWARF] Support emitting .debug_ranges section in ELFYAML.
This patch enables yaml2elf to emit the .debug_ranges section.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D81217
2020-06-07 15:47:47 +08:00
Georgii Rymar 9d739a9157 [ObjectYAML] - Remove unused function. NFC.
Was introduced in D81005 by mistake.

Catched by BB:
http://lab.llvm.org:8011/builders/clang-ppc64le-rhel/builds/4070/steps/build%20stage%201/logs/stdio
2020-06-04 14:22:51 +03:00
Georgii Rymar c781e7370e [yaml2obj] - Add a way to exclude specified sections from the section header.
This implements a new "Excluded" key that can be used
to exclude entries from section header:

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

Differential revision: https://reviews.llvm.org/D81005
2020-06-04 13:50:35 +03:00
Georgii Rymar 5750f12b82 Revert "[yaml2obj] - Allocate the file space for SHT_NOBITS sections in some cases."
This reverts commit aa3a85cdaa.

There are problems with it. See here: https://reviews.llvm.org/D80629
2020-06-04 13:17:48 +03:00
Xing GUO a50f4eb2e9 [ObjectYAML][DWARF] Support emitting the .debug_aranges section in ELFYAML.
This patch enables yaml2obj to emit the .debug_aranges section in ELFYAML.

Known issues:
- The current implementation of `debug_aranges` doesn't support emitting `segment` in the `(segment, address, length)` tuple. I will fix it in a follow-up patch.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D80972
2020-06-04 08:56:00 +08:00
Georgii Rymar aa3a85cdaa [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
2020-06-02 17:19:24 +03:00
Xing GUO 373e98a3a5 [ObjectYAML][DWARF] Add DWARF entry in ELFYAML.
This patch adds a new DWARF entry in ELF YAML file.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D80203
2020-05-29 10:57:18 +08:00
Georgii Rymar ad07d5f394 [yaml2obj] - Implement the "SectionHeaderTable" tag.
With the "SectionHeaderTable" it is now possible to reorder
entries in the section header table.

It also allows to stop emitting the table.

Differential revision: https://reviews.llvm.org/D80002
2020-05-28 13:42:43 +03:00
Georgii Rymar 3d4c873a14 [yaml2obj] - Map section names to chunks for each ELFYAML::ProgramHeader early. NFCI.
Each `ELFYAML::ProgramHeader` currently contains a list of section names
included. We are trying to map them to Fill/Sections very late,
though we can create such mapping early, in `initProgramHeaders`.

The benefit is that with such change it is possible to access mapped
chunks earlier (for example during writing section content) and have
simpler code.

Differential revision: https://reviews.llvm.org/D80520
2020-05-26 12:32:10 +03:00
Georgii Rymar 304b0ed403 [yaml2obj] - Move "repeated section/fill name" check earlier.
This allows to simplify the code.
Doing checks early is generally useful.

Differential revision: https://reviews.llvm.org/D79985
2020-05-23 17:40:48 +03:00
Georgii Rymar 38c5d6f700 [yaml2obj] - Add a technical prefix for each unnamed chunk.
This change does not affect the produced binary.

In this patch I assign a technical suffix to each section/fill
(i.e. chunk) name when it is empty. It allows to simplify the code
slightly and improve error messages reported.

In the code we have the section to index mapping, SN2I, which is
globally used. With this change we can use it to map "empty"
names to indexes now, what is helpful.

Differential revision: https://reviews.llvm.org/D79984
2020-05-23 17:22:23 +03:00
Georgii Rymar baf3225987 [yaml2obj] - Implement the "Offset" property for the Fill Chunk.
Similar to a regular section chunk, a Fill should have this property.
This patch implements it.

Differential revision: https://reviews.llvm.org/D80190
2020-05-20 13:38:48 +03:00
Georgii Rymar e2b134b01a [yaml2obj] - Stop using square brackets for unique suffixes.
For describing section/symbol names we can use unique suffixes,
e.g:

```
- Name: '.foo [1]`
- Name: '.foo [2]`
```

It can be a problem (see https://reviews.llvm.org/D79984#inline-734829),
because `[]` are sometimes used to describe a macros:

```
- Name: "[[a0]]"
```

Seems the better approach is to use something else, like "()".
This patch does it and refactors the code related.

Differential revision: https://reviews.llvm.org/D80123
2020-05-19 12:59:13 +03:00
Georgii Rymar 7ccae2cece [yaml2obj] - Introduce the "Offset" property for sections.
Currently there is no good way to set a physical offset for a section:

* We have the `ShOffset` that allows to override the `sh_offset`, but
  it does not affect the real data written.
* We can use a `Filler` to create an artificial gap, but it is more like a hack
  rather than a proper solution for this problem.

This patch adds the `Offset` property which allows setting physical
offsets for sections.

It also generalizes the code, so that we set sh_offset field in one place

Differential revision: https://reviews.llvm.org/D78927
2020-05-15 11:23:44 +03:00
Georgii Rymar 9f9a08e19c [obj2yaml] - Program headers: simplify the computation of p_filesz.
Currently we have computations of `p_filesz` and `p_memsz` mixed together
with the use of a loop over fragments. After recent changes it is possible to
avoid using a loop for the computation of `p_filesz`, since we know that fragments
are sorted by their file offsets.

The main benefit of this change is that splits the computation of `p_filesz`
and `p_memsz` what is simpler and allows us to fix the computation of the
`p_memsz` independently (D78005 shows the issue that we have currently).

Differential revision: https://reviews.llvm.org/D78628
2020-04-24 15:23:16 +03:00
Georgii Rymar 34b3d5b66c [obj2yaml] - Zero initialize program headers. NFCI.
It allows to simplify the current code and also
might help for the code around.

It is also consistent with what we do for another headers,
e.g. section headers, elf file header etc.

Differential revision: https://reviews.llvm.org/D78627
2020-04-23 12:39:14 +03:00
Georgii Rymar 2bf5674317 [yaml2obj] - Program headers: add an additional check for `Offset`
The `Offset` field is used to set the file offset of a program header.
In a normal object it should not be greater than the minimal offset
of sections included into segment.

This patch adds a check for that and adds tests.

Differential revision: https://reviews.llvm.org/D78304
2020-04-22 12:49:05 +03:00
Georgii Rymar 87d33d9e09 [yaml2obj] - Change how p_offset is calculated when creating segments. NFCI.
This depends on D78361 and simplifies the computation of the `p_offset`.

Differential revision: https://reviews.llvm.org/D78363
2020-04-22 12:37:44 +03:00
Georgii Rymar 3471ae9dad [yaml2obj] - Verify that sections are sorted by their file offsets when creating segments.
This validates that sections listed for a segment in the YAML
declaration are ordered by their file offsets.

It might help to simplify the file size computation, but also
is useful by itself as helps to avoid issues in test cases and
to maintain their readability.

Differential revision: https://reviews.llvm.org/D78361
2020-04-21 15:50:42 +03:00