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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318433 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312603 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312585 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293224 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287081 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266919 91177308-0d34-0410-b5e6-96231b3b80d8
This removes a report_fatal_error from library and avoids checking a
section property for every section entry.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246656 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@244510 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241377 91177308-0d34-0410-b5e6-96231b3b80d8
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"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241354 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241350 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241156 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240950 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240939 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239409 91177308-0d34-0410-b5e6-96231b3b80d8
This change adds support for the SHT_MIPS_ABIFLAGS section
reading/writing to the obj2yaml and yaml2obj tools.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236738 91177308-0d34-0410-b5e6-96231b3b80d8
The ELF symbol `st_other` field might contain additional flags besides
visibility ones. This patch implements support for some MIPS specific
flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221491 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we have a lib/MC/MCAnalysis, the dependency was there just because
of two helper classes. Move the two over to MC.
This will allow IRObjectFile to parse inline assembly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212248 91177308-0d34-0410-b5e6-96231b3b80d8
field represents ELF section header sh_info field and does not have any
sense for regular sections. Its interpretation depends on section type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209801 91177308-0d34-0410-b5e6-96231b3b80d8
Now the only method to configure ELF section's content and size is to assign
a hexadecimal string to the `Content` field. Unfortunately this way is
completely useless when you need to declare a really large section.
To solve this problem this patch adds one more optional field `Size`
to the `RawContentSection` structure. When yaml2obj generates an ELF file
it uses the following algorithm:
1. If both `Content` and `Size` fields are missed create an empty section.
2. If only `Content` field is missed take section length from the `Size`
field and fill the section by zero.
3. If only `Size` field is missed create a section using data from
the `Content` field.
4. If both `Content` and `Size` fields are provided validate that the `Size`
value is not less than size of `Content` data. Than take section length
from the `Size`, fill beginning of the section by `Content` and the rest
by zero.
Examples
--------
* Create a section 0x10000 bytes long filled by zero
Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC ]
Size: 0x10000
* Create a section 0x10000 bytes long starting from 'CA' 'FE' 'BA' 'BE'
Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC ]
Content: CAFEBABE
Size: 0x10000
The patch reviewed by Michael Spencer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208995 91177308-0d34-0410-b5e6-96231b3b80d8
The ELF header e_flags field in the MIPS related test cases handled
incorrectly. The obj2yaml prints too many flags. I will fix that in the
next patches.
The patch reviewed by Michael Spencer and Sean Silva.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208752 91177308-0d34-0410-b5e6-96231b3b80d8
