Previously the description allowed to describe symbols with use of
`Name` and `Index` keys. This patch removes them and now it is still
possible to use either names or symbol indexes, but the code is simpler
and the format is slightly different.
Such a change will be useful for another patches, e.g:
https://reviews.llvm.org/D73788#inline-671077
Differential revision: https://reviews.llvm.org/D73888
Note: this is a reland with a trivial 2 lines fix in ELFState<ELFT>::writeSectionContent.
It adds a check similar to ones we already have for other sections to fix the case revealed
by bots, like http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/60744.
The encoded sequence of Elf*_Relr entries in a SHT_RELR section looks
like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
i.e. start with an address, followed by any number of bitmaps. The address
entry encodes 1 relocation. The subsequent bitmap entries encode up to 63(31)
relocations each, at subsequent offsets following the last address entry.
More information is here:
https://github.com/llvm-mirror/llvm/blob/master/lib/Object/ELF.cpp#L272
This patch adds a support for these sections.
Differential revision: https://reviews.llvm.org/D71872
The encoded sequence of Elf*_Relr entries in a SHT_RELR section looks
like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
i.e. start with an address, followed by any number of bitmaps. The address
entry encodes 1 relocation. The subsequent bitmap entries encode up to 63(31)
relocations each, at subsequent offsets following the last address entry.
More information is here:
https://github.com/llvm-mirror/llvm/blob/master/lib/Object/ELF.cpp#L272
This patch adds a support for these sections.
Differential revision: https://reviews.llvm.org/D71872
There was no way to set an unsupported or unknown OS ABI.
With this patch it is possible to use any numeric value.
Differential revision: https://reviews.llvm.org/D71765
Currently we have the `Flags` property that allows to
set flags for a section. The problem is that it does not
allow us to set an arbitrary value, because of bit fields
validation under the hood. An arbitrary values can be used
to test specific broken cases.
We probably do not want to relax the validation, so this
patch adds a `ShSize` property that allows to
override the `sh_size`. It is inline with others `Sh*` properties
we have already.
Differential revision: https://reviews.llvm.org/D71411
The PT_GNU_PROPERTY is generated by a linker to describe the
.note.gnu.property section. The Linux kernel uses this program header to
locate the .note.gnu.property section.
It is described in "The Linux gABI extension"
Include support for llvm-readelf, llvm-readobj and the yaml reader and
writers.
Differential Revision: https://reviews.llvm.org/D70959
This section contains strings specifying libraries to be added to the link by the linker.
The strings are encoded as standard null-terminated UTF-8 strings.
This patch adds a way to describe and dump SHT_LLVM_DEPENDENT_LIBRARIES sections.
I introduced a new YAMLFlowString type here. That used to teach obj2yaml to dump
them like:
```
Libraries: [ foo, bar ]
```
instead of the following (if StringRef would be used):
```
Libraries:
- foo
- bar
```
Differential revision: https://reviews.llvm.org/D70598
SHT_LLVM_LINKER_OPTIONS section contains pairs of null-terminated strings.
This patch adds support for them.
Differential revision: https://reviews.llvm.org/D69895
Currently there is no way to describe the data that is not a part of an output section.
It can be a data used to align sections or to fill the gaps with something,
or another kind of custom data. In this patch I suggest a way to describe it. It looks like that:
```
Sections:
- Type: CustomFiller
Pattern: "CCDD"
Size: 4
- Name: .bar
Type: SHT_PROGBITS
Content: "FF"
```
I.e. I've added a kind of synthetic section with a synthetic type "CustomFiller".
In the code it is called a "SyntheticFiller", which is "a synthetic section which
might be used to write the custom data around regular output sections. It does
not present in the sections header table, but it might affect the output file size and
program headers produced. Think about it as about piece of data."
`SyntheticFiller` currently has a `Pattern` field and a `Size` field + an optional `Name`.
When written, `Size` of bytes in the output will be filled with a `Pattern`.
It is possible to reference a named filler it by name from the program headers description,
just like any other normal section.
Differential revision: https://reviews.llvm.org/D69709
Currently, when we do not specify "Info" field in a YAML description
for SHT_GROUP section, yaml2obj reports an error:
"error: unknown symbol referenced: '' by YAML section '.group1'"
Also, we do not link it with a symbol table by default,
though it is what we do for AddrsigSection, HashSection, RelocationSection.
(http://www.sco.com/developers/gabi/latest/ch4.sheader.html#sh_link)
The patch fixes missings mentioned.
Differential revision: https://reviews.llvm.org/D69299
SHT_NOTE is the section that consists of
namesz, descsz, type, name + padding, desc + padding data.
This patch teaches yaml2obj, obj2yaml to dump and parse them.
This patch implements the section how it is described here:
https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-18048.html
Which says: "For 64–bit objects and 32–bit objects, each entry is an array of 4-byte words in
the format of the target processor"
The official specification is different
http://www.sco.com/developers/gabi/latest/ch5.pheader.html#note_section
And says: "n 64-bit objects (files with e_ident[EI_CLASS] equal to ELFCLASS64), each entry is an array
of 8-byte words in the format of the target processor. In 32-bit objects (files with e_ident[EI_CLASS]
equal to ELFCLASS32), each entry is an array of 4-byte words in the format of the target processor"
Since LLVM uses the first, 32-bit way, this patch follows it.
Differential revision: https://reviews.llvm.org/D68983
It allows using "Size" with or without "Content" in YAML descriptions of
SHT_LLVM_ADDRSIG sections.
Differential revision: https://reviews.llvm.org/D68334
llvm-svn: 373610
This is a follow-up for D68085 which allows using "Size"
tag together with "Content" tag or alone.
Differential revision: https://reviews.llvm.org/D68216
llvm-svn: 373473
Currently we can't use unique suffixes in section names to describe
stack sizes sections. E.g. '.stack_sizes [1]' will be treated as a regular section.
This happens because we recognize stack sizes section by name and
do not yet drop the suffix before the check.
The patch fixes it.
Differential revision: https://reviews.llvm.org/D68018
llvm-svn: 372853
It is a follow-up requested in the review comment
for D67757. Allows to use Content + Size or just Size
when describing .stack_sizes sections in YAML document
Differential revision: https://reviews.llvm.org/D67958
llvm-svn: 372845
.stack_sizes is a SHT_PROGBITS section that contains pairs of
<address (4/8 bytes), stack size (uleb128)>.
This patch teach tools to parse and dump it.
Differential revision: https://reviews.llvm.org/D67757
llvm-svn: 372762
Currently when e_machine is set to something that is not supported by YAML lib,
then tools fail with llvm_unreachable.
In this patch I allow them to handle relocations in this case.
It can be used to dump and create objects for broken or unsupported targets.
Differential revision: https://reviews.llvm.org/D67657
llvm-svn: 372377
We do not support them and fail with llvm_unreachable currently.
This is not the only target we do not support and also seems we are missing
the tests for those we have already. But I needed this one for another patch,
so posted it separatelly.
Relocation names are taken from llvm\include\llvm\BinaryFormat\ELFRelocs\PowerPC64.def
Differential revision: https://reviews.llvm.org/D67615
llvm-svn: 372109
Currently we only allow using a known named constants
for `Machine` field in YAML documents.
This patch allows using any numbers (valid or "unknown")
and adds test cases for current and new functionality.
With this it is possible to write a test cases for really unknown
EM_* targets.
Differential revision: https://reviews.llvm.org/D67652
llvm-svn: 372108
`struct Elf*_Shdr` has a field `sh_offset`, named `ShOffset` in
llvm::ELFYAML::Section. Rename SHOffset (e_shoff) to SHOff to prevent confusion.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67254
llvm-svn: 371185
See http://lists.llvm.org/pipermail/llvm-dev/2019-February/130583.html
and D60242 for the lld partition feature.
This patch:
* Teaches yaml2obj to parse the 3 section types.
* Teaches llvm-readobj/llvm-readelf to dump the 3 section types.
There is no test for SHT_LLVM_DEPENDENT_LIBRARIES in llvm-readobj. Add
it as well.
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D67228
llvm-svn: 371157
Fix: added missing return "return 0;"
Original commit message:
This eliminates one of the error(1) call in this lib.
It is different from the others because happens on a fields mapping stage
and can be easily fixed.
Differential revision: https://reviews.llvm.org/D67150
llvm-svn: 371030
This eliminates one of the error(1) call in this lib.
It is different from the others because happens on a fields mapping stage
and can be easily fixed.
Differential revision: https://reviews.llvm.org/D67150
llvm-svn: 371023
PT_GNU_STACK is used in an llvm-objcopy test.
I plan to use PT_GNU_RELRO in a patch to improve nested segment
processing in llvm-objcopy (PR42963).
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67146
llvm-svn: 370857
This is in line with the previous changes which allowed to
override the sh_offset/sh_size and useful for writing test cases.
Differential revision: https://reviews.llvm.org/D66998
llvm-svn: 370633
Currenly we can encode the 'st_other' field of symbol using 3 fields.
'Visibility' is used to encode STV_* values.
'Other' is used to encode everything except the visibility, but it can't handle arbitrary values.
'StOther' is used to encode arbitrary values when 'Visibility'/'Other' are not helpfull enough.
'st_other' field is used to encode symbol visibility and platform-dependent
flags and values. Problem to encode it is that it consists of Visibility part (STV_* values)
which are enumeration values and the Other part, which is different and inconsistent.
For MIPS the Other part contains flags for all STO_MIPS_* values except STO_MIPS_MIPS16.
(Like comment in ELFDumper says: "Someones in their infinite wisdom decided to make
STO_MIPS_MIPS16 flag overlapped with other ST_MIPS_xxx flags."...)
And for PPC64 the Other part might actually encode any value.
This patch implements custom logic for handling the st_other and removes
'Visibility' and 'StOther' fields.
Here is an example of a new YAML style this patch allows:
- Name: foo
Other: [ 0x4 ]
- Name: bar
Other: [ STV_PROTECTED, 4 ]
- Name: zed
Other: [ STV_PROTECTED, STO_MIPS_OPTIONAL, 0xf8 ]
Differential revision: https://reviews.llvm.org/D66886
llvm-svn: 370472
This relands this commit, I mistakenly reverted the original change
thinking it was the cause of the observed MSan failures but it was not.
llvm-svn: 370206
This is a follow up discussed in the comments of D66583.
Currently, if for example, we have both StOther and Other set in YAML document for a symbol,
then yaml2obj reports an "unknown key 'Other'" error.
It happens because 'mapOptional()' is never called for 'Other/Visibility' in this case,
leaving those unhandled.
This message does not describe the reason of the error well. This patch fixes it.
Differential revision: https://reviews.llvm.org/D66642
llvm-svn: 370032
st_other field of a symbol usually contains its visibility.
Other bits are usually 0, though some targets, like
MIPS can set them using the named bit field values.
Problem is that there is no way to set an arbitrary value now,
though that might be useful for our test cases.
In this patch I introduced a way to set st_other to any numeric
value using the new StOther field.
I added a test and simplified the existent one to show the effect/benefit
Differential revision: https://reviews.llvm.org/D66583
llvm-svn: 369742
In some cases a symbol might have section index == SHN_XINDEX.
This is an escape value indicating that the actual section header index
is too large to fit in the containing field.
Then the SHT_SYMTAB_SHNDX section is used. It contains the 32bit values
that stores section indexes.
ELF gABI says that there can be multiple SHT_SYMTAB_SHNDX sections,
i.e. for example one for .symtab and one for .dynsym
(1) https://groups.google.com/forum/#!topic/generic-abi/-XJAV5d8PRg
(2) DT_SYMTAB_SHNDX: http://www.sco.com/developers/gabi/latest/ch5.dynamic.html
In this patch I am only supporting a single SHT_SYMTAB_SHNDX associated
with a .symtab. This is a more or less common case which is used a few tests I saw in LLVM.
I decided not to create the SHT_SYMTAB_SHNDX section as "implicit",
but implement is like a kind of regular section for now.
i.e. tools do not recreate this section or its content, like they do for
symbol table sections, for example. That should allow to write all kind of
possible broken test cases for our needs and keep the output closer to requested.
Differential revision: https://reviews.llvm.org/D65446
llvm-svn: 368272
There is no way to set broken sh_size field currently
for sections. It can be usefull for writing the
test cases.
Differential revision: https://reviews.llvm.org/D64401
llvm-svn: 365766
Some of our test cases are using objects which
has sections with a broken sh_offset field.
There was no way to set it from YAML until this patch.
Differential revision: https://reviews.llvm.org/D63879
llvm-svn: 364898
This allows setting different values for e_shentsize, e_shoff, e_shnum
and e_shstrndx fields and is useful for producing broken inputs for various
test cases.
Differential revision: https://reviews.llvm.org/D63771
llvm-svn: 364517
Summary:
The directive defines a symbol as an group/local memory (LDS) symbol.
LDS symbols behave similar to common symbols for the purposes of ELF,
using the processor-specific SHN_AMDGPU_LDS as section index.
It is the linker and/or runtime loader's job to "instantiate" LDS symbols
and resolve relocations that reference them.
It is not possible to initialize LDS memory (not even zero-initialize
as for .bss).
We want to be able to link together objects -- starting with relocatable
objects, but possible expanding to shared objects in the future -- that
access LDS memory in a flexible way.
LDS memory is in an address space that is entirely separate from the
address space that contains the program image (code and normal data),
so having program segments for it doesn't really make sense.
Furthermore, we want to be able to compile multiple kernels in a
compilation unit which have disjoint use of LDS memory. In that case,
we may want to place LDS symbols differently for different kernels
to save memory (LDS memory is very limited and physically private to
each kernel invocation), so we can't simply place LDS symbols in a
.lds section.
Hence this solution where LDS symbols always stay undefined.
Change-Id: I08cbc37a7c0c32f53f7b6123aa0afc91dbc1748f
Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61493
llvm-svn: 364296