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.
llvm-svn: 241450
Add support for resolving MIPS32r6 relocations in MCJIT.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D10687
llvm-svn: 241442
Requested by Eugene Rozenfeld of the LLILC team, this feature allows JIT
clients to skip relocations for selected external symbols by returning ~0ULL
from their symbol resolver. If this value is returned for a given symbol,
RuntimeDyld will skip all relocations for that symbol. The client will be
responsible for applying the skipped relocations manually before the code
is executed.
llvm-svn: 241383
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.
llvm-svn: 241297
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.
llvm-svn: 241028
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.
llvm-svn: 240777
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.
llvm-svn: 240529
So far, LLVM has not emitted correct addend for N64 and N32 ABI. This patch
fixes that. It also removes fixup from MCJIT for R_MIPS_PC16 relocation.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D10565
llvm-svn: 240404
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.
llvm-svn: 240176
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module. Represent the dependency explicitly to prevent
that.
llvm-svn: 239796
fix segfault by checking for UnknownArch, since
getArchTypePrefix() will return nullptr for UnknownArch.
This fixes regression caused by r238424.
llvm-svn: 239456
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
This patch adds R_MIPS_PC32 relocation for Mips64.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D10235
llvm-svn: 239301
The windows buildbot originally failed because the check expressions are
evaluated as 64-bit values, even for 32-bit symbols. Fixed this by comparing
bottom 32-bits of the expressions.
The host/target endian mismatch issue is that it's invalid to read/write target
values using a host pointer without taking care of endian differences between
the target and host. Most (if not all) instances of
reinterpret_cast<uint32_t*>() in the RuntimeDyld are examples of this bug.
This has been fixed for Mips using the endian aware read/write functions.
The original commits were:
r238838:
[mips] Add RuntimeDyld tests for currently supported O32 relocations.
Reviewers: petarj, vkalintiris
Reviewed By: vkalintiris
Subscribers: vkalintiris, llvm-commits
Differential Revision: http://reviews.llvm.org/D10126
r238844:
[mips][mcjit] Add support for R_MIPS_PC32.
Summary:
This allows us to resolve relocations for DW_EH_PE_pcrel TType encodings
in the exception handling LSDA.
Also fixed a nearby typo.
Reviewers: petarj, vkalintiris
Reviewed By: vkalintiris
Subscribers: vkalintiris, llvm-commits
Differential Revision: http://reviews.llvm.org/D10127
llvm-svn: 238915
Summary:
This allows us to resolve relocations for DW_EH_PE_pcrel TType encodings
in the exception handling LSDA.
Also fixed a nearby typo.
Reviewers: petarj, vkalintiris
Reviewed By: vkalintiris
Subscribers: vkalintiris, llvm-commits
Differential Revision: http://reviews.llvm.org/D10127
llvm-svn: 238844
Add support for resolving MIPS64r2 and MIPS64r6 relocations in MCJIT.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D9667
llvm-svn: 238424
Summary:
This supersedes http://reviews.llvm.org/D4010, hopefully properly
dealing with the JIT case and also adds an actual test case.
DwarfContext was basically already usable for the JIT (and back when
we were overwriting ELF files it actually worked out of the box by
accident), but in order to resolve relocations correctly it needs
to know the load address of the section.
Rather than trying to get this out of the ObjectFile or requiring
the user to create a new ObjectFile just to get some debug info,
this adds the capability to pass in that info directly.
As part of this I separated out part of the LoadedObjectInfo struct
from RuntimeDyld, since it is now required at a higher layer.
Reviewers: lhames, echristo
Reviewed By: echristo
Subscribers: vtjnash, friss, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D6961
llvm-svn: 237961
isInt is a little easier to read, let's use that more consistently.
Incidentally, this also silences a warning for shifting a negative
number.
This fixes PR23532.
llvm-svn: 237476
This reapplies r235060 and 235070, which were reverted because of test failures
in LLDB. The failure was caused because at moment RuntimeDyld is processing
relocations for all sections, irrespective of whether we actually load them
into memory or not, but RuntimeDyld was not actually remembering where in memory
the unrelocated section is. This commit includes a fix for that issue by
remembering that pointer, though the longer term fix should be to stop processing
unneeded sections.
Original Summary:
This allows us to get rid of the original unrelocated object file after
we're done processing relocations (but before applying them).
MachO and COFF already do not require this (currently we have temporary hacks
to prevent ownership from being released, but those are brittle and should be
removed soon).
The placeholder mechanism allowed the relocation resolver to look at original
object file to obtain more information that are required to apply the
relocations. This is usually necessary in two cases:
- For relocations targetting sub-word memory locations, there may be pieces
of the instruction at the target address which we should not override.
- Some relocations on some platforms allow an extra addend to be encoded in
their immediate fields.
The problem is that in the second case the information cannot be recovered
after the relocations have been applied once because they will have been
overridden. In the first case we also need to be careful to not use any bits
that aren't fixed and may have been overriden by applying a first relocation.
In the past both have been fixed by just looking at original object file. This
patch attempts to recover the information from the first by looking at the
relocated object file, while the extra addend in the second case is read
upon relocation processing and addend to the regular addend.
I have tested this on X86. Other platforms represent my best understanding
of how those relocations should work, but I may have missed something because
I do not have access to those platforms.
We will keep the ugly workarounds in place for a couple of days, so this commit
can be reverted if it breaks the bots.
Differential Revision: http://reviews.llvm.org/D9028
llvm-svn: 236341
Summary:
This allows us to get rid of the original unrelocated object file after
we're done processing relocations (but before applying them).
MachO and COFF already do not require this (currently we have temporary hacks
to prevent ownership from being released, but those are brittle and should be
removed soon).
The placeholder mechanism allowed the relocation resolver to look at original
object file to obtain more information that are required to apply the
relocations. This is usually necessary in two cases:
- For relocations targetting sub-word memory locations, there may be pieces
of the instruction at the target address which we should not override.
- Some relocations on some platforms allow an extra addend to be encoded in
their immediate fields.
The problem is that in the second case the information cannot be recovered
after the relocations have been applied once because they will have been
overridden. In the first case we also need to be careful to not use any bits
that aren't fixed and may have been overriden by applying a first relocation.
In the past both have been fixed by just looking at original object file. This
patch attempts to recover the information from the first by looking at the
relocated object file, while the extra addend in the second case is read
upon relocation processing and addend to the regular addend.
I have tested this on X86. Other platforms represent my best understanding
of how those relocations should work, but I may have missed something because
I do not have access to those platforms.
We will keep the ugly workarounds in place for a couple of days, so this commit
can be reverted if it breaks the bots.
Reviewers: petarj, t.p.northover, lhames
Reviewed By: lhames
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D9028
llvm-svn: 235060
Summary:
This is the first in a series of patches to eventually add support for TLS relocations to RuntimeDyld. This patch resolves an issue in the current GOT handling, where GOT entries would be reused between object files, which leads to the same situation that necessitates the GOT in the first place, i.e. that the 32-bit offset can not cover all of the address space. Thus this patch makes the GOT object-file-local.
Unfortunately, this still isn't quite enough, because the MemoryManager does not yet guarantee that sections are allocated sufficiently close to each other, even if they belong to the same object file. To address this concern, this patch also adds a small API abstraction on top of the GOT allocation mechanism that will allow (temporarily, until the MemoryManager is improved) using the stub mechanism instead of allocating a different section. The actual switch from separate section to stub mechanism will be part of a follow-on commit, so that it can be easily reverted independently at the appropriate time.
Test Plan: Includes a test case where the GOT of two object files is artificially forced to be apart by several GB.
Reviewers: lhames
Reviewed By: lhames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8813
llvm-svn: 234839
The patch is generated using clang-tidy misc-use-override check.
This command was used:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
-checks='-*,misc-use-override' -header-filter='llvm|clang' \
-j=32 -fix -format
http://reviews.llvm.org/D8925
llvm-svn: 234679
Rafael Espindola