Produce another specific error message for a malformed Mach-O file when a symbol’s
section index is more than the number of sections. The existing test case in test/Object/macho-invalid.test
for macho-invalid-section-index-getSectionRawName now reports the error with the message indicating
that a symbol at a specific index has a bad section index and that bad section 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.
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.
llvm-svn: 268298
Also replaces a number of calls to report_fatal_error with Error returns.
The plumbing will make it easier to return errors originating in libObject.
Replacing report_fatal_errors with Error returns will give JIT clients the
opportunity to recover gracefully when the JIT is unable to produce/relocate
code, as well as providing meaningful error messages that can be used to file
bug reports.
llvm-svn: 267776
The previous allocation code was over-estimating the amount of memory required.
No test case: we don't currently have a good way to detect conervative
over-allocation.
llvm-svn: 267041
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
in the test suite. While this is not really an interesting tool and option to run
on a Mach-O file to show the symbol table in a generic libObject format
it shouldn’t crash.
The reason for the crash was in MachOObjectFile::getSymbolType() when it was
calling MachOObjectFile::getSymbolSection() without checking its return value
for the error case.
What makes this fix require a fair bit of diffs is that the method getSymbolType() is
in the class ObjectFile defined without an ErrorOr<> so I needed to add that all
the sub classes. And all of the uses needed to be updated and the return value
needed to be checked for the error case.
The MachOObjectFile version of getSymbolType() “can” get an error in trying to
come up with the libObject’s internal SymbolRef::Type when the Mach-O symbol
symbol type is an N_SECT type because the code is trying to select from the
SymbolRef::ST_Data or SymbolRef::ST_Function values for the SymbolRef::Type.
And it needs the Mach-O section to use isData() and isBSS to determine if
it will return SymbolRef::ST_Data.
One other possible fix I considered is to simply return SymbolRef::ST_Other
when MachOObjectFile::getSymbolSection() returned an error. But since in
the past when I did such changes that “ate an error in the libObject code” I
was asked instead to push the error out of the libObject code I chose not
to implement the fix this way.
As currently written both the COFF and ELF versions of getSymbolType()
can’t get an error. But if isReservedSectionNumber() wanted to check for
the two known negative values rather than allowing all negative values or
the code wanted to add the same check as in getSymbolAddress() to use
getSection() and check for the error then these versions of getSymbolType()
could return errors.
At the end of the day the error printed now is the generic “Invalid data was
encountered while parsing the file” for object_error::parse_failed. In the
future when we thread Lang’s new TypedError for recoverable error handling
though libObject this will improve. And where the added // Diagnostic(…
comment is, it would be changed to produce and error message
like “bad section index (42) for symbol at index 8” for this case.
llvm-svn: 264187
This is a more generic version of the MCJITMemoryManager::notifyObjectLoaded
method: It provides only a RuntimeDyld reference (rather than an
ExecutionEngine), and so can be used with ORC JIT stacks.
llvm-svn: 257296
RuntimeDyld::MemoryManager.
The RuntimeDyld::MemoryManager::reserveAllocationSpace method is called when
object files are loaded, and gives clients a chance to pre-allocate memory for
all segments. Previously only the size of each segment (code, ro-data, rw-data)
was supplied but not the alignment. This hasn't caused any problems so far, as
most clients allocate via the MemoryBlock interface which returns page-aligned
blocks. Adding alignment arguments enables finer grained allocation while still
satisfying alignment restrictions.
llvm-svn: 257294
managers.
Prior to this patch, recursive finalization (where finalization of one
RuntimeDyld instance triggers finalization of another instance on which the
first depends) could trigger memory access failures: When the inner (dependent)
RuntimeDyld instance and its memory manager are finalized, memory allocated
(but not yet relocated) by the outer instance is locked, and relocation in the
outer instance fails with a memory access error.
This patch adds a latch to the RuntimeDyld::MemoryManager base class that is
checked by a new method: RuntimeDyld::finalizeWithMemoryManagerLocking, ensuring
that shared memory managers are only finalized by the outermost RuntimeDyld
instance.
This allows ORC clients to supply the same memory manager to multiple calls to
addModuleSet. In particular it enables the use of user-supplied memory managers
with the CompileOnDemandLayer which must reuse the supplied memory manager for
each function that is lazily compiled.
llvm-svn: 257263
DenseMap is most applicable when both keys and values are small.
In this case, the value violates that assumption, causing quite
significant memory overhead. A std::unordered_map is more appropriate
in this case (or at least fixed the memory problems I was seeing).
Differential Revision: http://reviews.llvm.org/D14910
llvm-svn: 254651
Summary:
For relocation types that are known to not require stub functions, there
is no need to allocate extra space for the stub functions.
Reviewers: lhames, reames, maksfb
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14676
llvm-svn: 253920
Summary:
Change SectionEntry to keep track of the size of its underlying
allocation, and use that to bounds check advanceStubOffset.
Reviewers: lhames, andrew.w.kaylor, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14675
llvm-svn: 253919
Summary:
Remove naked access to the data members in `SectionEntry` and route
accesses through accessor functions. This makes it obvious how the
instances of the class are used, and will also facilitate adding bounds
checking to `advanceStubOffset` in a later change.
Reviewers: lhames, loladiro, andrew.w.kaylor
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14674
llvm-svn: 253918
Summary: ELF's STT_File symbols may overlap with regular globals in
other files, so we should ignore them here in order to avoid having
bogus entries in the symbol table that confuse us when resolving relocations.
Reviewers: lhames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13888
llvm-svn: 250942
(e.g. bss sections).
MachO and ELF have been silently letting this pass, but COFFObjectFile contains
an assertion to catch this kind of (ab)use of the getSectionContents, and this
was causing the JIT to crash on COFF objects with BSS sections. This patch
should fix that.
llvm-svn: 250371
Summary:
Rather than just iterating over all sections and checking whether we have relocations for them, iterate over the relocation map instead. This showed up heavily in an artificial julia benchmark that does lots of compilation. On that particular benchmark, this patch gives
~15% performance improvements. As far as I can tell the primary reason why the original
loop was so expensive is that Relocations[i] actually constructs a relocationList (allocating memory & doing lots of other unnecessary computing) if none is found.
Reviewers: lhames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13545
llvm-svn: 249942
before any relocations have been applied, and again after all relocations have
been applied.
Previously each section was dumped before and after relocations targetting it
were applied, but this only shows the impact of relocations that point to other
symbols in the same section.
llvm-svn: 247335
Code-section alignment should be at least as high as the minimum
stub alignment. If the section alignment is lower it can cause
padding to be emitted resulting in alignment errors if the section
is mapped to a higher alignment on the target.
E.g. If a text section with a 4-byte alignment gets 4-bytes of
padding to guarantee 8-byte alignment for stubs but is re-mapped to
an 8-byte alignment on the target, the 4-bytes of padding will push
the stubs to 4-byte alignment causing a crash.
No test case: There is currently no way to control host section
alignment in llvm-rtdyld. This could be made testable by adding
a custom memory manager. I'll look at that in a follow-up patch.
llvm-svn: 245031
Previously, for O32 ABI we did not calculate correct addend for R_MIPS_HI16
and R_MIPS_PCHI16 relocations. This patch fixes that.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D11186
llvm-svn: 244897
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
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
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
Add support for resolving MIPS64r2 and MIPS64r6 relocations in MCJIT.
Patch by Vladimir Radosavljevic.
Differential Revision: http://reviews.llvm.org/D9667
llvm-svn: 238424
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 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
ensure that section addresses are distinct.
mapSectionAddress will fail if two sections are allocated the same address,
which can happen if any section has zero size (since malloc(0) is implementation
defined). Unfortunately I've been unable to repro this with a simple test case.
Fixes <rdar://problem/20314015>.
llvm-svn: 234299
MCJIT.
This patch decouples the two responsibilities of the RTDyldMemoryManager class,
memory management and symbol resolution, into two new classes:
RuntimeDyld::MemoryManager and RuntimeDyld::SymbolResolver.
The symbol resolution interface is modified slightly, from:
uint64_t getSymbolAddress(const std::string &Name);
to:
RuntimeDyld::SymbolInfo findSymbol(const std::string &Name);
The latter passes symbol flags along with symbol addresses, allowing RuntimeDyld
and others to reason about non-strong/non-exported symbols.
The memory management interface removes the following method:
void notifyObjectLoaded(ExecutionEngine *EE,
const object::ObjectFile &) {}
as it is not related to memory management. (Note: Backwards compatibility *is*
maintained for this method in MCJIT and OrcMCJITReplacement, see below).
The RTDyldMemoryManager class remains in-tree for backwards compatibility.
It inherits directly from RuntimeDyld::SymbolResolver, and indirectly from
RuntimeDyld::MemoryManager via the new MCJITMemoryManager class, which
just subclasses RuntimeDyld::MemoryManager and reintroduces the
notifyObjectLoaded method for backwards compatibility).
The EngineBuilder class retains the existing method:
EngineBuilder&
setMCJITMemoryManager(std::unique_ptr<RTDyldMemoryManager> mcjmm);
and includes two new methods:
EngineBuilder&
setMemoryManager(std::unique_ptr<MCJITMemoryManager> MM);
EngineBuilder&
setSymbolResolver(std::unique_ptr<RuntimeDyld::SymbolResolver> SR);
Clients should use EITHER:
A single call to setMCJITMemoryManager with an RTDyldMemoryManager.
OR (exclusive)
One call each to each of setMemoryManager and setSymbolResolver.
This patch should be fully compatible with existing uses of RTDyldMemoryManager.
If it is not it should be considered a bug, and the patch either fixed or
reverted.
If clients find the new API to be an improvement the goal will be to deprecate
and eventually remove the RTDyldMemoryManager class in favor of the new classes.
llvm-svn: 233509
Author: Lang Hames <lhames@gmail.com>
Date: Mon Mar 9 23:51:09 2015 +0000
[Orc][MCJIT][RuntimeDyld] Add header that was accidentally left out of r231724.
Author: Lang Hames <lhames@gmail.com>
Date: Mon Mar 9 23:44:13 2015 +0000
[Orc][MCJIT][RuntimeDyld] Add symbol flags to symbols in RuntimeDyld. Thread the
new types through MCJIT and Orc.
In particular, add a 'weak' flag. When plumbed through RTDyldMemoryManager, this
will allow us to distinguish between weak and strong definitions and find the
right ones during symbol resolution.
llvm-svn: 231731
new types through MCJIT and Orc.
In particular, add a 'weak' flag. When plumbed through RTDyldMemoryManager, this
will allow us to distinguish between weak and strong definitions and find the
right ones during symbol resolution.
llvm-svn: 231724
Provide basic support for dynamically loadable coff objects. Only handles a subset of x64 currently.
Patch by Andy Ayers!
Differential Revision: http://reviews.llvm.org/D7793
llvm-svn: 231574
This has wider implications than I expected when I reviewed the patch: It can
cause JIT crashes where clients have used the default value for AbortOnFailure
during symbol lookup. I'm currently investigating alternative approaches and I
hope to have this back in tree soon.
llvm-svn: 227287
Support weak symbols by first looking up if there is an externally visible symbol we can find,
and only if that fails using the one in the object file we're loading.
Reviewed By: lhames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6950
llvm-svn: 227228
This patch adds a new set of JIT APIs to LLVM. The aim of these new APIs is to
cleanly support a wider range of JIT use cases in LLVM, and encourage the
development and contribution of re-usable infrastructure for LLVM JIT use-cases.
These APIs are intended to live alongside the MCJIT APIs, and should not affect
existing clients.
Included in this patch:
1) New headers in include/llvm/ExecutionEngine/Orc that provide a set of
components for building JIT infrastructure.
Implementation code for these headers lives in lib/ExecutionEngine/Orc.
2) A prototype re-implementation of MCJIT (OrcMCJITReplacement) built out of the
new components.
3) Minor changes to RTDyldMemoryManager needed to support the new components.
These changes should not impact existing clients.
4) A new flag for lli, -use-orcmcjit, which will cause lli to use the
OrcMCJITReplacement class as its underlying execution engine, rather than
MCJIT itself.
Tests to follow shortly.
Special thanks to Michael Ilseman, Pete Cooper, David Blaikie, Eric Christopher,
Justin Bogner, and Jim Grosbach for extensive feedback and discussion.
llvm-svn: 226940
RuntimeDyld symbol info previously consisted of just a Section/Offset pair. This
patch replaces that pair type with a SymbolInfo class that also tracks symbol
visibility. A new method, RuntimeDyld::getExportedSymbolLoadAddress, is
introduced which only returns a non-zero result for exported symbols. For
non-exported or non-existant symbols this method will return zero. The
RuntimeDyld::getSymbolAddress method retains its current behavior, returning
non-zero results for all symbols regardless of visibility.
No in-tree clients of RuntimeDyld are changed. The newly introduced
functionality will be used by the Orc APIs.
No test case: Since this patch doesn't modify the behavior for any in-tree
clients we don't have a good tool to test this with yet. Once Orc is in we can
use it to write regression tests that test these changes.
llvm-svn: 226341
Peter Collingbourne