Currently, YAML has the following syntax for describing the symbols:
Symbols:
Local:
LocalSymbol1:
...
LocalSymbol2:
...
...
Global:
GlobalSymbol1:
...
Weak:
...
GNUUnique:
I.e. symbols are grouped by their bindings. That is not very convenient,
because:
It does not allow to set a custom binding, what can be useful for producing
broken/special outputs for test cases. Adding a new binding would require to
change a syntax (what we observed when added GNUUnique recently).
It does not allow to change the order of the symbols in .symtab/.dynsym,
i.e. currently all Local symbols are placed first, then Global, Weak and GNUUnique
are following, but we are not able to change the order.
It is not consistent. Binding is just one of the properties of the symbol,
we do not group them by other properties.
It makes the code more complex that it can be. This patch shows it can be simplified
with the change performed.
The patch changes the syntax to just:
Symbols:
Symbol1:
...
Symbol2:
...
...
With that, we are able to work with the binding field just like with any other symbol property.
Differential revision: https://reviews.llvm.org/D60122
llvm-svn: 357595
This is for tweaking SHT_SYMTAB sections.
Their sh_info contains the (number of symbols + 1) usually.
But for creating invalid inputs for test cases it would be convenient
to allow explicitly override this field from YAML.
Differential revision: https://reviews.llvm.org/D58779
llvm-svn: 355193
This fixes https://bugs.llvm.org/show_bug.cgi?id=40786
("obj2yaml symbol output missing section index for SHN_ABS and SHN_COMMON symbols")
Since SHN_ABS and SHN_COMMON symbols are special, we should preserve
the st_shndx for them. The patch does this for them and the other special symbols.
The test case is based on the test provided by James Henderson at the bug page!
Differential revision: https://reviews.llvm.org/D58498
llvm-svn: 354661
Fix:
Replace
assert(!IO.getContext() && "The IO context is initialized already");
with
assert(IO.getContext() && "The IO context is not initialized");
(this was introduced in r354329, where I tried to quickfix the darwin BB
and seems copypasted the assert from the wrong place).
Original commit message:
The section is described here:
https://refspecs.linuxfoundation.org/LSB_1.3.0/gLSB/gLSB/symverrqmts.html
Patch just teaches obj2yaml/yaml2obj to dump and parse such sections.
We did the finalization of string tables very late,
and I had to move the logic to make it a bit earlier.
That was needed in this patch since .gnu.version_r adds strings to .dynstr.
This might also be useful for implementing other special sections.
Everything else changed in this patch seems to be straightforward.
Differential revision: https://reviews.llvm.org/D58119
llvm-svn: 354335
The section is described here:
https://refspecs.linuxfoundation.org/LSB_1.3.0/gLSB/gLSB/symverrqmts.html
Patch just teaches obj2yaml/yaml2obj to dump and parse such sections.
We did the finalization of string tables very late,
and I had to move the logic to make it a bit earlier.
That was needed in this patch since .gnu.version_r adds strings to .dynstr.
This might also be useful for implementing other special sections.
Everything else changed in this patch seems to be straightforward.
Differential revision: https://reviews.llvm.org/D58119
llvm-svn: 354328
ELFYAML.h contains a `Section` class which is a base for a few other
sections classes that are used for mapping different section types.
`Section` has a `StringRef Info` field used for storing sh_info.
At the same time, sh_info has very different meanings for sections and
cannot be processed in a similar way generally,
for example ELFDumper does not handle it in `dumpCommonSection`
but do that in `dumpGroup` and `dumpCommonRelocationSection` respectively.
At this moment, we have and handle it as a string, because that was possible for
the current use case. But also it can simply be a number:
For SHT_GNU_verdef is "The number of version definitions within the section."
The patch moves `Info` field out to be able to have it as a number.
With that change, each class will be able to decide what type and purpose
of the sh_info field it wants to use.
I also had to edit 2 test cases. This is because patch fixes a bug. Previously we
accepted yaml files with Info fields for all sections (for example, for SHT_DYNSYM too).
But we do not handle it and the resulting objects had zero sh_info fields set for
such sections. Now it is accepted only for sections that supports it.
Differential revision: https://reviews.llvm.org/D58054
llvm-svn: 353810
This teaches the tools to parse and dump
the .dynamic section and its dynamic tags.
Differential revision: https://reviews.llvm.org/D57691
llvm-svn: 353606
I faced with the fact that obj2yaml does not dump the sh_entsize field.
A problem arose when I tried to dump ELF versioning sections.
This is close to what D50235 did, but D50235 did the change for yaml2obj, and now
I had to do the same for obj2yaml.
Differential revision: https://reviews.llvm.org/D57229
llvm-svn: 352373
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
These tools were assuming ABI version is 0,
that is not always true.
Patch teaches them to work with that field.
Differential revision: https://reviews.llvm.org/D55884
llvm-svn: 349737
Summary:
This change introduces a `DynamicSymbols` field to the ELF specific YAML
supported by `yaml2obj` and `obj2yaml`. This grouping of symbols provides a way
to represent ELF dynamic symbols. The `DynamicSymbols` structure is identical to
the existing `Symbols`.
Reviewers: compnerd, jakehehrlich, silvas
Reviewed By: silvas
Subscribers: silvas, jakehehrlich, llvm-commits
Differential Revision: https://reviews.llvm.org/D39582
llvm-svn: 318433
Summary: Previously we would dereference Symtab without checking for null.
Reviewers: davide, atanasyan, rafael
Reviewed By: davide, atanasyan
Differential Revision: https://reviews.llvm.org/D38080
llvm-svn: 313970
Without this we would have multiple relocations pointing to symbols
with the same name: the empty string. There was no way for yaml2obj to
be able to handle that.
A more general solution would be to unique symbol names in a similar
way to how we unique section names. In practice I think this covers
all common cases and is a bit more user friendly than using names like
sym1, sym2, sym3, etc.
llvm-svn: 312603
Without this patch passing a .o file with multiple sections with the
same name to obj2yaml produces a yaml file that yaml2obj cannot
handle. This is pr34162.
The problem is that when specifying, for example, the section of a
symbol, we get only
Section: foo
and don't know which of the sections whose name is foo we have to use.
One alternative would be to use section numbers. This would work, but
the output from obj2yaml would be very inconvenient to edit as
deleting a section would invalidate all indexes.
Another alternative would be to invent a unique section id that would
exist only on yaml. This would work, but seems a bit heavy handed. We
could make the id optional and default it to the section name.
Since in the last alternative the id is basically what this patch uses
as a name, it can be implemented as a followup patch if needed.
llvm-svn: 312585
R_X86_64_NONE can be emitted without a symbol associated (well,
in theory it should never be emitted in an ABI-compliant relocatable
object). So, if there's no symbol associated to a reloc, emit one
with an empty name, instead of crashing.
Ack'ed by Michael Spencer offline.
PR: 31768
llvm-svn: 293224
This has two advantages:
1) We slowly move away from ErrorOr to the new handling interface,
in the hope of having an uniform error handling in LLVM, eventually.
2) We're starting to have *meaningful* error messages for invalid
object ELF files, rather than a generic "parse error". At some point
we should include also the offset to improve the quality of the
diagnostic.
llvm-svn: 287081
Produce another specific error message for a malformed Mach-O file when a symbol’s
string index is past the end of the string table. The existing test case in test/Object/macho-invalid.test
for macho-invalid-symbol-name-past-eof now reports the error with the message indicating
that a symbol at a specific index has a bad sting index and that bad string index value.
Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same. There is some
code for this that could be factored into a routine but I would like to leave that for
the code owners post-commit to do as they want for handling an llvm::Error. An
example of how this could be done is shown in the diff in
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h which had a Check() routine
already for std::error_code so I added one like it for llvm::Error .
Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values. So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.
Note there fixes needed to lld that goes along with this that I will commit right after this.
So expect lld not to built after this commit and before the next one.
llvm-svn: 266919
With this we finally have an ELFFile that is O(1) to construct. This is helpful
for programs like lld which have to do their own section walk.
llvm-svn: 244510
SHT_NOBITS sections do not have content in an object file. Now the yaml2obj
tool does not accept `Content` field for such sections, and the obj2yaml
tool does not attempt to read the section content from a file.
Restore r241350 and r241352.
llvm-svn: 241377
r241350 broke lld tests.
r241352 depends on r241350.
Original messages:
"[ELFYAML] Fix handling SHT_NOBITS sections by obj2yaml/yaml2obj tools"
"[ELFYAML] Make the Size field for .bss section optional"
llvm-svn: 241354
SHT_NOBITS sections do not have content in an object file. Now yaml2obj
tool does not accept `Content` field for such sections, and obj2yaml
tool does not attempt to read the section content from a file.
llvm-svn: 241350
This also improves the logic of what is an error:
* getSection(uint_32): only return an error if the index is out of bounds. The
index 0 corresponds to a perfectly valid entry.
* getSection(Elf_Sym): Returns null for symbols that normally don't have
sections and error for out of bound indexes.
In many places this just moves the report_fatal_error up the stack, but those
can then be fixed in smaller patches.
llvm-svn: 241156
This moves the error checking for string tables to getStringTable which returns
an ErrorOr<StringRef>.
This improves error checking, makes it uniform across all string tables and
makes it possible to check them once instead of once per name.
llvm-svn: 240950
It was a fairly broken concept for an ELF only class.
An ELF file can have two symbol tables, but they have exactly the same
format. There is no concept of a dynamic or a static symbol. Storing this
on the iterator also makes us do more work per symbol than necessary. To fetch
a name we would:
* Find if we had a static or a dynamic symbol.
* Look at the corresponding symbol table and find the string table section.
* Look at the string table section to fetch its contents.
* Compute the name as a substring of the string table.
All but the last step can be done per symbol table instead of per symbol. This
is a step in that direction.
llvm-svn: 240939
make_error_code(object_error) is slow because object::object_category()
uses a ManagedStatic variable. But the real problem is that the function is
called too frequently. This patch uses std::error_code() instead of
object_error::success. In most cases, we return "success", so this patch
reduces number of function calls to that function.
http://reviews.llvm.org/D10333
llvm-svn: 239409
