With the help of @lhames, this PR introduces a push-request model to manage
initializers in the runtime state for each `JITDylib`, similar to how `MachO`
and `COFF` handle it. Previously, the ELF runtime lacked the ability to
register, deregister, or retain initializers, causing issues when re-running
`dlopen`. Initializers were erased after `rt_getInitializers` was used.
To address this, we introduce `__orc_rt_elfnix_register_init_sections` and
`__orc_rt_elfnix_register_jitdylib` (and corresponding deregister functions).
This model allows the runtime to request the push of initializers for the
`JITDylib`, with the platform handling this via a record method. Additionally,
we leverage `MachO`'s `RecordSectionsTracker` to store initializers, ensuring
only newly updated initializers are executed using `processNewSections`,
improving the runtime's efficiency and reliability.
This reapplies commits 462251b80b7 and 9b67c99dc5b, which were reverted in
53d35c4e86b due to bot failures for the wrapper_function_utils_test.cpp unit
test.
This decouples function argument serialization / deserialization from the
function call dispatch mechanism. This will eventually allow us to replace the
existing __orc_rt_jit_dispatch function with a system that supports pre-linking
parts of the ORC runtime into the executor.
We should use `orc_rt` as the public C++ API namespace for the ORC runtime and
control symbol visibility to hide implementation details, rather than rely on
the '__' prefix.
ORC's ELF platform support prefers the newer libunwind registration functions
(__unw_add_dynamic_eh_frame_section, __unw_remove_dynamic_eh_frame_section) when
they're available, and falls back to the older registration functions
(__register_frame, __deregister_frame) when they're not.
Until now the choice of registration functions has been made on the controller
side in ELFNixPlatform: The platform JITDylib was searched for the registration
functions and aliases set depending on which ones were found. This patch drops
that selection logic from ELFNixPlatform and instead uses weak imports of the
registration functions in elfnix_platform.cpp to identify which ones are
available and choose which ones to use.
This has a few small benefits:
(1) The registration functions don't need to be defined in the same JITDylib as
the ORC runtime -- it's sufficient for them to be defined in a JITDylib that the
ORC runtime's JITDylib links against.
(2) THe elfnix_platfrom code is more readable, as we don't have to dig into
ELFNixPlatform.cpp on the controller side to discover the definition of the
registration aliases.
(3) We may save a separate round-trip to look up the registration APIs (the
lookup will be folded into the ordinary external symbol lookup when linking the
runtime).
The '__' prefix should only be used for the parts of the ORC runtime that
implement compiler / loader runtime details (e.g. ORC-RT's __tlv_get_addr
implementations).
This patch only fixes the public API. Future changes will fix internal names.
1dcff823db9 updated the ORC runtime to use std::string_view, rather than its
own placeholder class (__orc_rt::string_view), but failed to add these
includes.
b1356504e63 enabled the use of c++17 features in LLVM, which means that we can
drop the ORC runtime's placeholder string_view implemention in favor of
std::string_view.
Implements TLS descriptor relocations in JITLink ELF/AARCH64 backend and support the relevant runtime functions in ELFNixPlatform.
Unlike traditional TLS model, TLS descriptor model requires linker to return the "offset" from thread pointer via relocaiton not the actual pointer to thread local variable. There is no public libc api for adding new allocations to TLS block dynamically which thread pointer points to. So, we support this by taking delta from thread base pointer to the actual thread local variable in our allocated section.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D128601
ELF-based platforms currently support defining multiple static
initializer table sections with differing priorities, for example
.init_array.0 or .init_array.100; the default .init_array corresponds
to a priority of 65535. When building a shared library or executable,
the system linker normally sorts these sections and combines them into
a single .init_array section. This change adds the capability to
recognize ELF static initializers with priorities other than the
default, and to properly sort them by priority, to Orc and the Orc
runtime.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D127056
This changes the ELFNix platform Orc runtime to use, when available,
the __unw_add_dynamic_eh_frame_section interface provided by libunwind
for registering .eh_frame sections loaded by JITLink. When libunwind
is not being used for unwinding, the ELFNix platform detects this and
defaults to the __register_frame interface provided by libgcc_s.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D114961
There is a bug reported at https://bugs.llvm.org/show_bug.cgi?id=48938
After looking through the glibc, I found the `atexit(f)` is the same as `__cxa_atexit(f, NULL, NULL)`. In orc runtime, we identify different JITDylib by their dso_handle value, so that a NULL dso_handle is invalid. So in this patch, I added a `PlatformJDDSOHandle` to ELFNixRuntimeState, and functions which are registered by atexit will be registered at PlatformJD.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D111413
Renames StartAddress and EndAddress members to Start and End.
Adds contains and overlap methods.
Adds a constructor from an address and size.
These changes are counterparts to LLVM commits ef391df2b6332, c0d889995e708, and
37f1b7a3f35fd.
This is an ORC-runtime counterpart to LLVM commit ef391df2b63, and the
motivation is the same: to move to a shorter name to improve the ergonomics of
this type before it's more widely adopted.
This patch use the same way as the https://reviews.llvm.org/rGfe1fa43f16beac1506a2e73a9f7b3c81179744eb to handle the thread local variable.
It allocates 2 * pointerSize space in GOT to represent the thread key and data address. Instead of using the _tls_get_addr function, I customed a function __orc_rt_elfnix_tls_get_addr to get the address of thread local varible. Currently, this is a wip patch, only one TLS relocation R_X86_64_TLSGD is supported and I need to add the corresponding test cases.
To allocate the TLS descriptor in GOT, I need to get the edge kind information in PerGraphGOTAndPLTStubBuilder, So I add a `Edge::Kind K` argument in some functions in PerGraphGOTAndPLTStubBuilder.h. If it is not suitable, I can think further to solve this problem.
Differential Revision: https://reviews.llvm.org/D109293
This change adds support to ORCv2 and the Orc runtime library for static
initializers, C++ static destructors, and exception handler registration for
ELF-based platforms, at present Linux and FreeBSD on x86_64. It is based on the
MachO platform and runtime support introduced in bb5f97e3ad1.
Patch by Peter Housel. Thanks very much Peter!
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D108081
