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
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
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
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
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
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
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
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
In this patch, emitDebugPubnames(), emitDebugPubtypes(),
emitDebugGNUPubnames(), emitDebugGNUPubtypes() are added.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D85003
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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