A request has been made to the official registry, but an official value is
not yet available. This patch uses a temporary value in order to support
development. When an official value is recieved, the value of EM_WEBASSEMBLY
will be updated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257517 91177308-0d34-0410-b5e6-96231b3b80d8
Also adds a 'trivial' ELF file. This was generated by assembling
and linking a file with the symbol main which contains a single
return instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251096 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
This function can actually fail since the symbol contains an index to the
section and that can be invalid.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@244375 91177308-0d34-0410-b5e6-96231b3b80d8
getSymbolValue now returns a value that in convenient for most callers:
* 0 for undefined
* symbol size for common symbols
* offset/address for symbols the rest
Code that needs something more specific can check getSymbolFlags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241605 91177308-0d34-0410-b5e6-96231b3b80d8
Originally added in r139314.
Back then it didn't actually get the address, it got whatever value the
relocation used: address or offset.
The values in different object formats are:
* MachO: Always an offset.
* COFF: Always an address, but when talking about the virtual address of
sections it says: "for simplicity, compilers should set this to zero".
* ELF: An offset for .o files and and address for .so files. In the case of the
.so, the relocation in not linked to any section (sh_info is 0). We can't
really compute an offset.
Some API mappings would be:
* Use getAddress for everything. It would be quite cumbersome. To compute the
address elf has to follow sh_info, which can be corrupted and therefore the
method has to return an ErrorOr. The address of the section is also the same
for every relocation in a section, so we shouldn't have to check the error
and fetch the value for every relocation.
* Use a getValue and make it up to the user to know what it is getting.
* Use a getOffset and:
* Assert for dynamic ELF objects. That is a very peculiar case and it is
probably fair to ask any tool that wants to support it to use ELF.h. The
only tool we have that reads those (llvm-readobj) already does that. The
only other use case I can think of is a dynamic linker.
* Check that COFF .obj files have sections with zero virtual address spaces. If
it turns out that some assembler/compiler produces these, we can change
COFFObjectFile::getRelocationOffset to subtract it. Given COFF format,
this can be done without the need for ErrorOr.
The getRelocationAddress method was never implemented for COFF. It also
had exactly one use in a very peculiar case: a shortcut for adding the
section value to a pcrel reloc on MachO.
Given that, I don't expect that there is any use out there of the C API. If
that is not the case, let me know and I will add it back with the implementation
inlined and do a proper deprecation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241450 91177308-0d34-0410-b5e6-96231b3b80d8
The ELFObjectFile now just reasons about a section/index pair, removing
one of the users that force ELF.h to maintain the difference.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241344 91177308-0d34-0410-b5e6-96231b3b80d8
This function can really fail since the string table offset can be out of
bounds.
Using ErrorOr makes sure the error is checked.
Hopefully a lot of the boilerplate code in tools/* can go away once we have
a diagnostic manager in Object.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241297 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
We can probably do better in this method, but this is an improvement and
enables further ErrorOr cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241114 91177308-0d34-0410-b5e6-96231b3b80d8
Realistically, this will be returning ErrorOr for some time as refactoring the
user code to check once per section will take some time.
Given that, use it for checking if a relocation has addend or not.
While at it, add ELFRelocationRef to simplify the users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241028 91177308-0d34-0410-b5e6-96231b3b80d8
If a section is not SHT_REL or SHT_RELA, we never create a valid iterator,
so the getRelocation* methods should always see a section with the correct type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241023 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
This is still a really odd function. Most calls are in object format specific
contexts and should probably be replaced with a more direct query, but at least
now this is not too obnoxious to use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240777 91177308-0d34-0410-b5e6-96231b3b80d8
* Have it return a iterator_range.
* Remove the global function.
* Rename to getDynamicSymbolIterators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240644 91177308-0d34-0410-b5e6-96231b3b80d8
This returns either the symbol offset or address. Since it is not defined which
one, it never has to lookup the section and so never fails.
I will add users in the next commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240569 91177308-0d34-0410-b5e6-96231b3b80d8
It is perfectly possible for SHNDX to contain indexes that have the same value
as reserved st_shndx values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240544 91177308-0d34-0410-b5e6-96231b3b80d8
COFF and MachO only define symbol sizes for common symbols. Reflect that
in the class hierarchy by having a method for common symbols only in the base
and a general one in ELF.
This avoids the need of using a magic value for the size, which had a few
problems
* Most callers didn't check for it.
* The ones that did could not tell the magic value from a file actually having
that value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240529 91177308-0d34-0410-b5e6-96231b3b80d8
This patch changes getRelocationAddend to use ErrorOr and considers it an error
to try to get the addend of a REL section.
If, for example, a x86_64 file has a REL section, that file is corrupted and
we should reject it.
Using ErrorOr is not ideal since we check the section type once per relocation
instead of once per section.
Checking once per section would involve getRelocationAddend just asserting and
callers checking the section before iterating over the relocations.
In any case, this is an improvement and includes a test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240176 91177308-0d34-0410-b5e6-96231b3b80d8
