Removes CodeAlignmentFactor and DataAlignmentFactor validation in EHFrameEdgeFixer. I observed some of aarch64 elf files generated by clang contains CIE record with code_alignment_factor = 4 or data_alignment_factor = -8. code_alignment_factor and data_alignment_factor are used by call fram instruction that should be correctled handled by libunwind.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D127062
Adds support for pointer encodings commonly used in large/static models,
including non-pcrel, sdata/udata8, indirect, and omit.
Also refactors pointer-encoding handling to consolidate error generation inside
common functions, rather than callees of those functions.
The sort should have been lexicographic, but wasn't. This resulted in us
choosing a common symbol at address zero over the intended target function,
leading to a crash.
This patch also moves sorting up to the start of the pass, which means that we
only need to hold on to the canonical symbol at each address rather than a list
of candidates.
With 229d576b31f4071ab68c85ac4fabb78cfa502b04 the class EHFrameSplitter was renamed to DWARFRecordSectionSplitter. This change merely moves it to it's own .cpp/.h file
Differential Revision: https://reviews.llvm.org/D121721
EHFrameSplitter does the exact same work to split up the eh_frame as it would need for any section that follows the DWARF record, therefore this patch just changes the name of it to DWARFRecordSectionSplitter to be more general.
Differential Revision: https://reviews.llvm.org/D121486
This re-applies 133f86e95492b2a00b944e070878424cfa73f87c, which was reverted in
c5965a411c635106a47738b8d2e24db822b7416f while I investigated bot failures.
The original failure contained an arithmetic conversion think-o (on line 419 of
EHFrameSupport.cpp) that could cause failures on 32-bit platforms. The issue
should be fixed in this patch.
Some files still contained the old University of Illinois Open Source
Licence header. This patch replaces that with the Apache 2 with LLVM
Exception licence.
Differential Revision: https://reviews.llvm.org/D107528
Adds utilities for creating anonymous pointers and jump stubs to x86_64.h. These
are used by the GOT and Stubs builder, but may also be used by pass writers who
want to create pointer stubs for indirection.
This patch also switches the underlying type for LinkGraph content from
StringRef to ArrayRef<char>. This avoids any confusion when working with buffers
that contain null bytes in the middle like, for example, a newly added null
pointer content array. ;)
JITLink now requires section names to be unique. In MachO section names are only
guaranteed to be unique within their containing segment (e.g. a '__const' section
in the '__DATA' segment does not clash with a '__const' section in the '__TEXT'
segment), so we need to use the fully qualified <segment>,<section> section
names (e.g. '__DATA,__const' or '__TEXT,__const') when constructing
jitlink::Sections for MachO objects.
Adds the EHFrameSplitter and EHFrameEdgeFixer passes to the default JITLink
pass pipeline for ELF/x86-64, and teaches EHFrameEdgeFixer to handle some
new pointer encodings.
Together these changes enable exception handling (at least for the basic
cases that I've tested so far) for ELF/x86-64 objects loaded via JITLink.
Previously FDE field names were used, but the fixup kind used for a field can
vary based on the pointer encoding.
This change will improve readability / maintainability when EH-frame support is
added to JITLink/ELF.
implementation.
This patch aims to improve support for out-of-process JITing using OrcV2. It
introduces two new class templates, OrcRPCTargetProcessControlBase and
OrcRPCTPCServer, which together implement the TargetProcessControl API by
forwarding operations to an execution process via an Orc-RPC Endpoint. These
utilities are used to implement out-of-process JITing from llvm-jitlink to
a new llvm-jitlink-executor tool.
This patch also breaks the OrcJIT library into three parts:
-- OrcTargetProcess: Contains code needed by the JIT execution process.
-- OrcShared: Contains code needed by the JIT execution and compiler
processes
-- OrcJIT: Everything else.
This break-up allows JIT executor processes to link against OrcTargetProcess
and OrcShared only, without having to link in all of OrcJIT. Clients executing
JIT'd code in-process should start linking against OrcTargetProcess as well as
OrcJIT.
In the near future these changes will enable:
-- Removal of the OrcRemoteTargetClient/OrcRemoteTargetServer class templates
which provided similar functionality in OrcV1.
-- Restoration of Chapter 5 of the Building-A-JIT tutorial series, which will
serve as a simple usage example for these APIs.
-- Implementation of lazy, cross-target compilation in lli's -jit-kind=orc-lazy
mode.
The macro HAVE_EHTABLE_SUPPORT is used by parts of ExecutionEngine to tell __register_frame/__deregister_frame is available to register the
FDE for a generated (JIT) code. It's currently set by a slowly growing set of macro tests in the respective headers, which is updated now and then when it fails to link on some platform or another due to the symbols being missing (see for example https://bugs.llvm.org/show_bug.cgi?id=5715).
This change converts the macro in two HAVE_(DE)REGISTER_FRAME config.h macros (like most of the other HAVE_* macros) and set's them based on whether CMake can actually find a definition for these symbols to link to at configuration time.
Reviewed By: hubert.reinterpretcast
Differential Revision: https://reviews.llvm.org/D87114
The functions `__register_frame`/`__deregister_frame` are not
available on z/OS, so add a guard to not use them.
Reviewed By: lhames, abhina.sreeskantharajan
Differential Revision: https://reviews.llvm.org/D84787
Some targets (E.g. MachO/arm64) use relocations to fix some CFI record fields
in the eh-frame section. When relocations are used the initial (pre-relocation)
content of the eh-frame section can no longer be interpreted by following the
eh-frame specification. This causes errors in the existing eh-frame parser.
This patch moves eh-frame handling into two LinkGraph passes that are run after
relocations have been parsed (but before they are applied). The first] pass
breaks up blocks in the eh-frame section into per-CFI-record blocks, and the
second parses blocks of (potentially multiple) CFI records and adds the
appropriate edges to any CFI fields that do not have existing relocations.
These passes can be run independently of one another. By handling eh-frame
splitting/fixing with LinkGraph passes we can both re-use existing relocations
for CFI record fields and avoid applying eh-frame fixups before parsing the
section (which would complicate the linker and require extra temporary
allocations of working memory).
In the Atom model the symbols, content and relocations of a relocatable object
file are represented as a graph of atoms, where each Atom represents a
contiguous block of content with a single name (or no name at all if the
content is anonymous), and where edges between Atoms represent relocations.
If more than one symbol is associated with a contiguous block of content then
the content is broken into multiple atoms and layout constraints (represented by
edges) are introduced to ensure that the content remains effectively contiguous.
These layout constraints must be kept in mind when examining the content
associated with a symbol (it may be spread over multiple atoms) or when applying
certain relocation types (e.g. MachO subtractors).
This patch replaces the Atom model in JITLink with a blocks-and-symbols model.
The blocks-and-symbols model represents relocatable object files as bipartite
graphs, with one set of nodes representing contiguous content (Blocks) and
another representing named or anonymous locations (Symbols) within a Block.
Relocations are represented as edges from Blocks to Symbols. This scheme
removes layout constraints (simplifying handling of MachO alt-entry symbols,
and hopefully ELF sections at some point in the future) and simplifies some
relocation logic.
llvm-svn: 373689
On MachO, processing of the eh-frame section should stop if the end of the
__eh_frame section is reached, regardless of whether or not there is a null CFI
length field at the end of the section. This patch tracks the eh-frame section
size and threads it through the appropriate APIs so that processing can be
terminated correctly.
No testcase yet: This patch is all API plumbing (rather than modification of
linked memory) which the existing infrastructure does not provide a way of
testing. Committing without a testcase until I have an idea of how to write
one.
llvm-svn: 370074
Replaces direct calls to eh-frame registration with calls to methods on an
EHFrameRegistrar instance. This allows clients to substitute a registrar that
registers frames in a remote process via IPC/RPC.
llvm-svn: 365098
Summary:
EH Frames aren't supported on AIX with the system compiler, but the definition of HAVE_EHTABLE_SUPPORT misses this which causes linking problems on AIX. This patch updates the definition of HAVE_EHTABLE_SUPPORT in both JITLink and RuntimeDyld.
Author: daltenty
Reviewers: sfertile, xingxue, hubert.reinterpretcase
Reviewed By: xingxue
Subscribers: hiraditya, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62203
llvm-svn: 361410
These operations were already used in eh-frame registration, and are likely to
be used in other runtime registrations, so this commit moves them into a header
where they can be re-used.
llvm-svn: 359950
ObjectLinkingLayer::Plugin provides event notifications when objects are loaded,
emitted, and removed. It also provides a modifyPassConfig callback that allows
plugins to modify the JITLink pass configuration.
This patch moves eh-frame registration into its own plugin, and teaches
llvm-jitlink to only add that plugin when performing execution runs on
non-Windows platforms. This should allow us to re-enable the test case that was
removed in r359198.
llvm-svn: 359357
Frame Descriptor Entries (FDEs) have a pointer back to a Common Information
Entry (CIE) that describes how the rest FDE should be parsed. JITLink had been
assuming that FDEs always referred to the most recent CIE encountered, but the
spec allows them to point back to any previously encountered CIE. This patch
fixes JITLink to look up the correct CIE for the FDE.
The testcase is a MachO binary with an FDE that refers to a CIE that is not the
one immediately proceeding it (the layout can be viewed wit
'dwarfdump --eh-frame <testcase>'. This test case had to be a binary as llvm-mc
now sorts FDEs (as of r356216) to ensure FDEs *do* point to the most recent CIE.
llvm-svn: 359105
