LLVMOrcDisposeObjectLayer and LLVMOrcExecutionSessionGetJITDylibByName did not
have matching signatures between the C-API header and binding implementations.
Fixes http://llvm.org/PR49745.
Patch by Mats Larsen. Thanks Mats!
Reviewed by: lhames
Differential Revision: https://reviews.llvm.org/D99478
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.
Apply the way createLocalIndirectStubsManagerBuilder() deals with unsupported achritectures to createLocalLazyCallThroughManager(). The returned call-through manager is dysfunctional: It runs into an unreachable as soon as a lazy JIT attempts to use it. However, this results in broader platform support for lli in default (greedy) ORC mode where no lazy materialization is required.
Don't leak ResourceKeys from MaterializationResponsibility::withResourceKeyDo() in notifyEmitted().
Also make some improvements in the overall implementation.
Differential Revision: https://reviews.llvm.org/D98863
There can be multiple MaterializationResponsibilitys in-flight for a single ResourceKey. Hence, pending debug objects must be tracked by MaterializationResponsibility and not by ResourceKey.
Differential Revision: https://reviews.llvm.org/D98785
This makes the target triple, graph name, and full graph content available
when making decisions about how to populate the linker pass pipeline.
Also updates the LLJITWithObjectLinkingLayerPlugin example to show more
API use, including use of the API changes in this patch.
During finalization the debug object is registered with the target. Materialization must wait for this process to finish. Otherwise we might start running code before the debugger finished processing the corresponding debug info.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D98417
Add a new ObjectLinkingLayer plugin `DebugObjectManagerPlugin` and infrastructure to handle creation of `DebugObject`s as well as their registration in OrcTargetProcess. The current implementation only covers ELF on x86-64, but the infrastructure is not limited to that.
The journey starts with a new `LinkGraph` / `JITLinkContext` pair being created for a `MaterializationResponsibility` in ORC's `ObjectLinkingLayer`. It sends a `notifyMaterializing()` notification, which is forwarded to all registered plugins. The `DebugObjectManagerPlugin` aims to create a `DebugObject` form the provided target triple and object buffer. (Future implementations might create `DebugObject`s from a `LinkGraph` in other ways.) On success it will track it as the pending `DebugObject` for the `MaterializationResponsibility`.
This patch only implements the `ELFDebugObject` for `x86-64` targets. It follows the RuntimeDyld approach for debug object setup: it captures a copy of the input object, parses all section headers and prepares to patch their load-address fields with their final addresses in target memory. It instructs the plugin to report the section load-addresses once they are available. The plugin overrides `modifyPassConfig()` and installs a JITLink post-allocation pass to capture them.
Once JITLink emitted the finalized executable, the plugin emits and registers the `DebugObject`. For emission it requests a new `JITLinkMemoryManager::Allocation` with a single read-only segment, copies the object with patched section load-addresses over to working memory and triggers finalization to target memory. For registration, it notifies the `DebugObjectRegistrar` provided in the constructor and stores the previously pending`DebugObject` as registered for the corresponding MaterializationResponsibility.
The `DebugObjectRegistrar` registers the `DebugObject` with the target process. `llvm-jitlink` uses the `TPCDebugObjectRegistrar`, which calls `llvm_orc_registerJITLoaderGDBWrapper()` in the target process via `TargetProcessControl` to emit a `jit_code_entry` compatible with the GDB JIT interface [1]. So far the implementation only supports registration and no removal. It appears to me that it wouldn't raise any new design questions, so I left this as an addition for the near future.
[1] https://sourceware.org/gdb/current/onlinedocs/gdb/JIT-Interface.html
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D97335
So far we had no way to distinguish between JITLink and RuntimeDyld in lli. Instead, we used implicit knowledge that RuntimeDyld would be used for linking ELF. In order to get D97337 to work with lli though, we have to move on and allow JITLink for ELF. This patch uses extensible RTTI to allow external clients to add their own layers without touching the LLVM sources.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D97338
This commit fixes how metadata is handled in CloneModule to be sound,
and improves how it's handled in CloneFunctionInto (although the latter
is still awkward when called within a module).
Ruiling Song pointed out in PR48841 that CloneModule was changed to
unsoundly use the RF_ReuseAndMutateDistinctMDs flag (renamed in
fa35c1f80f for clarity). This flag papered
over a crash caused by other various changes made to CloneFunctionInto
over the past few years that made it unsound to use cloning between
different modules.
(This commit partially addresses PR48841, fixing the repro from
preprocessed source but not textual IR. MDNodeMapper::mapDistinctNode
became unsound in df763188c9 and this
commit does not address that regression.)
RF_ReuseAndMutateDistinctMDs is designed for the IRMover to use,
avoiding unnecessary clones of all referenced metadata when linking
between modules (with IRMover, the source module is discarded after
linking). It never makes sense to use when you're not discarding the
source. This commit drops its incorrect use in CloneModule.
Sadly, the right thing to do with metadata when cloning a function is
complicated, and this patch doesn't totally fix it.
The first problem is that there are two different types of referenceable
metadata and it's not obvious what to with one of them when remapping.
- `!0 = !{!1}` is metadata's version of a constant. Programatically it's
called "uniqued" (probably a better term would be "constant") because,
like `ConstantArray`, it's stored in uniquing tables. Once it's
constructed, it's illegal to change its arguments.
- `!0 = distinct !{!1}` is a bit closer to a global variable. It's legal
to change the operands after construction.
What should be done with distinct metadata when cloning functions within
the same module?
- Should new, cloned nodes be created?
- Should all references point to the same, old nodes?
The answer depends on whether that metadata is effectively owned by a
function.
And that's the second problem. Referenceable metadata's ownership model
is not clear or explicit. Technically, it's all stored on an
LLVMContext. However, any metadata that is `distinct`, that transitively
references a `distinct` node, or that transitively references a
GlobalValue is specific to a Module and is effectively owned by it. More
specifically, some metadata is effectively owned by a specific Function
within a module.
Effectively function-local metadata was introduced somewhere around
c10d0e5ccd, which made it illegal for two
functions to share a DISubprogram attachment.
When cloning a function within a module, you need to clone the
function-local debug info and suppress cloning of global debug info (the
status quo suppresses cloning some global debug info but not all). When
cloning a function to a new/different module, you need to clone all of
the debug info.
Here's what I think we should do (eventually? soon? not this patch
though):
- Distinguish explicitly (somehow) between pure constant metadata owned
by the LLVMContext, global metadata owned by the Module, and local
metadata owned by a GlobalValue (such as a function).
- Update CloneFunctionInto to trigger cloning of all "local" metadata
(only), perhaps by adding a bit to RemapFlag. Alternatively, split
out a separate function CloneFunctionMetadataInto to prime the
metadata map that callers are updated to call ahead of time as
appropriate.
Here's the somewhat more isolated fix in this patch:
- Converted the `ModuleLevelChanges` parameter to `CloneFunctionInto` to
an enum called `CloneFunctionChangeType` that is one of
LocalChangesOnly, GlobalChanges, DifferentModule, and ClonedModule.
- The code maintaining the "functions uniquely own subprograms"
invariant is now only active in the first two cases, where a function
is being cloned within a single module. That's necessary because this
code inhibits cloning of (some) "global" metadata that's effectively
owned by the module.
- The code maintaining the "all compile units must be explicitly
referenced by !llvm.dbg.cu" invariant is now only active in the
DifferentModule case, where a function is being cloned into a new
module in isolation.
- CoroSplit.cpp's call to CloneFunctionInto in CoroCloner::create
uses LocalChangeOnly, since fa635d730f
only set `ModuleLevelChanges` to trigger cloning of local metadata.
- CloneModule drops its unsound use of RF_ReuseAndMutateDistinctMDs
and special handling of !llvm.dbg.cu.
- Fixed some outdated header docs and left a couple of FIXMEs.
Differential Revision: https://reviews.llvm.org/D96531
Compilers may insert new definitions during compilation, E.g. EH personality
function pointers, or named constant pool entries. This commit causes
ObjectLinkingLayer to attempt to claim responsibility for all weak definitions
in objects as they're linked. This is always safe (first claimant for each
symbol is granted responsibility, subsequent claims are rejected without error)
and prevents compiler-injected symbols from being dead-stripped (which they
will be if they remain unclaimed by anyone).
This change was motivated by errors seen by an out-of-tree client while testing
eh-frame support in JITLink ELF/x86-64: IR containing exceptions didn't define
DW.ref.__gxx_personality_v0 (since it's added by CodeGen), and this caused
DW.ref.__gxx_personality_v0 to be dead-stripped leading to linker failures.
No test case yet: We won't have a way to test in-tree until we enable JITLink
for lli on Linux.
It can be useful for an ObjectLinkingLayerCreator to allow callee errors to get propagated to the builder. Specifically, this is the case when the ObjectLayer uses the EHFrameRegistrationPlugin, because it requires a TPCEHFrameRegistrar and instantiation for it may fail (e.g. if the required registration symbols are missing in the target process).
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D94690
All other layers in LLJIT are stored as unique_ptr's already. At this point, it is not strictly necessary for ObjTransformLayer, but it makes a follow-up change more straightforward.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D94689
Moves all headers from Orc/RPC to Orc/Shared, and from the llvm::orc::rpc
namespace into llvm::orc::shared. Also renames RPCTypeName to
SerializationTypeName and Function to RPCFunction.
In addition to being a more reasonable home for this code, this will make it
easier for the upcoming Orc runtime to re-use the Serialization system for
creating and parsing wrapper-function binary blobs.
Separates link graph creation from linking. This allows raw LinkGraphs to be
created and passed to a link. ObjectLinkingLayer is updated to support emission
of raw LinkGraphs in addition to object buffers.
Raw LinkGraphs can be created by in-memory compilers to bypass object encoding /
decoding (though this prevents caching, as LinkGraphs have do not have an
on-disk representation), and by utility code to add programatically generated
data structures to the JIT target process.
JITLinkDylib represents a target dylib for a JITLink link. By representing this
explicitly we can:
- Enable JITLinkMemoryManagers to manage allocations on a per-dylib basis
(e.g by maintaining a seperate allocation pool for each JITLinkDylib).
- Enable new features and diagnostics that require information about the
target dylib (not implemented in this patch).
The LLVM_ENABLE_MODULES builds currently randomly fail due depending on the
headers generated by the intrinsics_gen target, but the current dependency only model
the non-modules dependencies:
```
While building module 'LLVM_ExecutionEngine' imported from llvm-project/llvm/lib/ExecutionEngine/Orc/Shared/TargetProcessControlTypes.cpp:13:
While building module 'LLVM_intrinsic_gen' imported from llvm-project/llvm/include/llvm/ExecutionEngine/Orc/ThreadSafeModule.h:17:
In file included from <module-includes>:1:
In file included from llvm-project/llvm/include/llvm/IR/Argument.h:18:
llvm/include/llvm/IR/Attributes.h:75:14: fatal error: 'llvm/IR/Attributes.inc' file not found
#include "llvm/IR/Attributes.inc"
^~~~~~~~~~~~~~~~~~~~~~~~
```
Depending on whether intrinsics_gen runs before compiling Orc/Shared files we either fail or include an outdated Attributes.inc
in module builds. The Clang modules require these additional dependencies as including/importing one module requires all
includes headers by that module to be parsable.
Differential Revision: https://reviews.llvm.org/D92873
There is one result per lookup symbol, so we have to advance the result iterator no matter whether it's NULL or not.
MissingSymbols variable is unused.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D91707
LLVMBuild has been removed from the build system. However, three LLVMBuild.txt
files remain in the tree. This patch simply removes them.
llvm/lib/ExecutionEngine/Orc/TargetProcess/LLVMBuild.txt
llvm/tools/llvm-jitlink/llvm-jitlink-executor/LLVMBuild.txt
llvm/tools/llvm-profgen/LLVMBuild.txt
Differential Revision: https://reviews.llvm.org/D92693
This reverts commit c6ef6e1690.
Basically, publicly linked libraries have a different semantic than components,
which link libraries privately.
Differential Revision: https://reviews.llvm.org/D91461
Use LINK_COMPONENTS instead of explicit target_link_libraries for components.
This avoids redundancy and potential inconsistencies.
Differential Revision: https://reviews.llvm.org/D91461
No longer rely on an external tool to build the llvm component layout.
Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.
These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.
Differential Revision: https://reviews.llvm.org/D90848
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.
This patch breaks Orc.h up into Orc.h, LLJIT.h and OrcEE.h.
Orc.h contain core Orc utilities.
LLJIT.h contains LLJIT specific types and functions.
OrcEE.h contains types and functions that depend on ExecutionEngine.
The intent is that these headers should match future library divisions: Clients
who only use Orc.h should only need to link againt the Orc core libraries,
clients using LLJIT.h will also need to link against LLVM core, and clients
using OrcEE.h will also have to link against ExecutionEngine.
In addition to breaking up the Orc.h header this patch introduces functions to:
(1) Set the object linking layer creation function on LLJITBuilder.
(2) Create an RTDyldObjectLinkingLayer instance (particularly for use in (1)).
(3) Register JITEventListeners with an RTDyldObjectLinkingLayer.
Together (1), (2) and (3) can be used to force use of RTDyldObjectLinkingLayer
as the underlying JIT linker for LLJIT, rather than the platform default, and
to register event listeners with the RTDyldObjectLinkingLayer.
C API clients can now define a custom definition generator by providing a
callback function (to implement DefinitionGenerator::tryToGenerate) and context
object. All arguments for the DefinitionGenerator::tryToGenerate method have
been given C API counterparts, and the API allows for optionally asynchronous
generation.
Symbol string pool entries are ref counted, but not automatically cleared.
This can cause the size of the pool to grow without bound if it's not
periodically cleared. These functions allow that to be done via the C API.
This patch moves definition generation out from the session lock, instead
running it under a per-dylib generator lock. It also makes the
DefinitionGenerator::tryToGenerate method optionally asynchronous: Generators
are handed an opaque LookupState object which can be captured to stop/restart
the lookup process.
The new scheme provides the following benefits and guarantees:
(1) Queries that do not need to attempt definition generation (because all
requested symbols matched against existing definitions in the JITDylib)
can proceed without being blocked by any running definition generators.
(2) Definition generators can capture the LookupState to continue their work
asynchronously. This allows generators to run for an arbitrary amount of
time without blocking a thread. Definition generators that do not need to
run asynchronously can return without capturing the LookupState to eliminate
unnecessary recursion and improve lookup performance.
(3) Definition generators still do not need to worry about concurrency or
re-entrance: Since they are still run under a (per-dylib) lock, generators
will never be re-entered concurrently, or given overlapping symbol sets to
generate.
Finally, the new system distinguishes between symbols that are candidates for
generation (generation candidates) and symbols that failed to match for a query
(due to symbol visibility). This fixes a bug where an unresolved symbol could
trigger generation of a duplicate definition for an existing hidden symbol.
MaterializationResponsibility, JITDylib, and ExecutionSession collectively
manage the OrcV2 core JIT state. Responsibility for maintaining and
updating this state has previously been spread among these classes, resulting
in implementations that are each non-trivial, but all tightly coupled. This has
in turn made reading the code and reasoning about state update and locking
rules difficult.
The core state model can be simplified by thinking of
MaterializationResponsibility and JITDylib as facets of ExecutionSession. This
commit is the first in a series intended to refactor Core.cpp to reflect this
model. Operations on MaterializationResponsibility and JITDylib will forward to
implementation methods inside ExecutionSession. Raw state will remain with the
original classes, but in most cases will only be modified by the
ExecutionSession.
This patch updates the Kaleidoscope and BuildingAJIT tutorial series (chapter
1-4) to OrcV2. Chapter 5 of the BuildingAJIT series is removed -- it will be
re-instated once we have in-tree support for out-of-process JITing.
This patch only updates the tutorial code, not the text. Patches welcome for
that, otherwise I will try to update it in a few weeks.
This patch introduces new APIs to support resource tracking and removal in Orc.
It is intended as a thread-safe generalization of the removeModule concept from
OrcV1.
Clients can now create ResourceTracker objects (using
JITDylib::createResourceTracker) to track resources for each MaterializationUnit
(code, data, aliases, absolute symbols, etc.) added to the JIT. Every
MaterializationUnit will be associated with a ResourceTracker, and
ResourceTrackers can be re-used for multiple MaterializationUnits. Each JITDylib
has a default ResourceTracker that will be used for MaterializationUnits added
to that JITDylib if no ResourceTracker is explicitly specified.
Two operations can be performed on ResourceTrackers: transferTo and remove. The
transferTo operation transfers tracking of the resources to a different
ResourceTracker object, allowing ResourceTrackers to be merged to reduce
administrative overhead (the source tracker is invalidated in the process). The
remove operation removes all resources associated with a ResourceTracker,
including any symbols defined by MaterializationUnits associated with the
tracker, and also invalidates the tracker. These operations are thread safe, and
should work regardless of the the state of the MaterializationUnits. In the case
of resource transfer any existing resources associated with the source tracker
will be transferred to the destination tracker, and all future resources for
those units will be automatically associated with the destination tracker. In
the case of resource removal all already-allocated resources will be
deallocated, any if any program representations associated with the tracker have
not been compiled yet they will be destroyed. If any program representations are
currently being compiled then they will be prevented from completing: their
MaterializationResponsibility will return errors on any attempt to update the
JIT state.
Clients (usually Layer writers) wishing to track resources can implement the
ResourceManager API to receive notifications when ResourceTrackers are
transferred or removed. The MaterializationResponsibility::withResourceKeyDo
method can be used to create associations between the key for a ResourceTracker
and an allocated resource in a thread-safe way.
RTDyldObjectLinkingLayer and ObjectLinkingLayer are updated to use the
ResourceManager API to enable tracking and removal of memory allocated by the
JIT linker.
The new JITDylib::clear method can be used to trigger removal of every
ResourceTracker associated with the JITDylib (note that this will only
remove resources for the JITDylib, it does not run static destructors).
This patch includes unit tests showing basic usage. A follow-up patch will
update the Kaleidoscope and BuildingAJIT tutorial series to OrcV2 and will
use this API to release code associated with anonymous expressions.
This removes all legacy layers, legacy utilities, the old Orc C bindings,
OrcMCJITReplacement, and OrcMCJITReplacement regression tests.
ExecutionEngine and MCJIT are not affected by this change.
Making MaterializationResponsibility instances immovable allows their
associated VModuleKeys to be updated by the ExecutionSession while the
responsibility is still in-flight. This will be used in the upcoming
removable code feature to enable safe merging of resource keys even if
there are active compiles using the keys being merged.
TPCDynamicLibrarySearchGenerator was generating errors on missing
symbols, but that doesn't fit the DefinitionGenerator contract: A symbol
that isn't generated by a particular generator should not cause an
error.
This commit fixes the error by using SymbolLookupFlags::WeaklyReferencedSymbol
for all elements of the lookup, and switches llvm-jitlink to use
TPCDynamicLibrarySearchGenerator.
If there's no initializer symbol in the current MaterializationResponsibility
then bail out without installing JITLink passes: they're going to be no-ops
anyway.
A think-o in the existing code meant that dependencies were never registered.
This failure could lead to crashes rather than orderly error propagation if
initialization dependencies failed to materialize.
No test case: The bug was discovered in an out-of-tree code and requires
pathalogically misconfigured JIT to generate the original error that lead to
the crash.
DFS and Reverse-DFS linkage orders are used to order execution of
deinitializers and initializers respectively.
This patch replaces uses of special purpose DFS order functions in
MachOPlatform and LLJIT with uses of the new methods.
This loop caused me a little headache once, because I didn't see the assigned variable is a member. The refactored version appears more readable to me.
Differential Revision: https://reviews.llvm.org/D85922
Archives can now be specified as input files the same way that object
files are. Archives will always be linked after all objects (regardless
of the relative order of the inputs) but before any dynamic libraries or
process symbols.
This patch also relaxes matching for slice triples in
StaticLibraryDefinitionGenerator in order to support this feature:
Vendors need not match if the source vendor is unknown.
This allows clients to detect invalid transformations applied by JITLink passes
(e.g. inserting or removing symbols in unexpected ways) and terminate linking
with an error.
This change is used to simplify the error propagation logic in
ObjectLinkingLayer.
Subclasses will commonly gather that information from a remote during
construction, in which case they won't have meaningful values to pass to
TargetProcessControl's constructor.
This patch makes ownership of the JITLinkMemoryManager by ObjectLinkingLayer
optional: the layer can still own the memory manager but no longer has to.
Evevntually we want to move to a state where ObjectLinkingLayer never owns its
memory manager. For now allowing optional ownership makes it easier to develop
classes that can dynamically use either RTDyldObjectLinkingLayer, which owns
its memory managers, or ObjectLinkingLayer (e.g. LLJIT).
TPCDynamicLibrarySearchGenerator uses a TargetProcessControl instance to
load libraries and search for symbol addresses in a target process. It
can be used in place of a DynamicLibrarySearchGenerator to enable
target-process agnostic lookup.
Lang Hames