The C-string section splitting support added in f9649d123db triggered an assert
("Duplicate canonical symbol at address") when multiple symbols were defined at
the the same offset within a C-string block (this triggered on arm64, where we
always add a block start symbol). The bug was caused by a failure to update the
record of the last canonical symbol address. The fix was to maintain this record
correctly, and move the auto-generation of the block-start symbol above the
handling for symbols defined in the object itself so that all symbols
(auto-generated and defined) are processed in address order.
MachO C-string literal sections should be split on null-terminator boundaries,
rather than the usual symbol boundaries. This patch updates
MachOLinkGraphBuilder to do that.
As suggested on rG937c4cffd024, use llvm_unreachable for unhandled integer types (which shouldn't be possible) instead of breaking and dropping down to the existing fatal error handler.
Helps silence static analyzer warnings.
During the generic x86-64 support refactor in ecf6466f01c52 the implementation
of MachO_arm64_GOTAndStubsBuilder::isGOTEdgeToFix was altered to only return
true for external symbols. This behavior is incorrect: GOT entries may be
required for defined symbols (e.g. in the large code model).
This patch fixes the bug and adds a test case for it (renaming an old test
case to avoid any ambiguity).
Currently, BPF only contains three relocations:
R_BPF_NONE for no relocation
R_BPF_64_64 for LD_imm64 and normal 64-bit data relocation
R_BPF_64_32 for call insn and normal 32-bit data relocation
Also .BTF and .BTF.ext sections contain symbols in allocated
program and data sections. These two sections reserved 32bit
space to hold the offset relative to the symbol's section.
When LLVM JIT is used, the LLVM ExecutionEngine RuntimeDyld
may attempt to resolve relocations for .BTF and .BTF.ext,
which we want to prevent. So we used R_BPF_NONE for such relocations.
This all works fine until when we try to do linking of
multiple objects.
. R_BPF_64_64 handling of LD_imm64 vs. normal 64-bit data
is different, so lld target->relocate() needs more context
to do a correct job.
. The same for R_BPF_64_32. More context is needed for
lld target->relocate() to differentiate call insn vs.
normal 32-bit data relocation.
. Since relocations in .BTF and .BTF.ext are set to R_BPF_NONE,
they will not be relocated properly when multiple .BTF/.BTF.ext
sections are merged by lld.
This patch intends to address this issue by adding additional
relocation kinds:
R_BPF_64_ABS64 for normal 64-bit data relocation
R_BPF_64_ABS32 for normal 32-bit data relocation
R_BPF_64_NODYLD32 for .BTF and .BTF.ext style relocations.
The old R_BPF_64_{64,32} semantics:
R_BPF_64_64 for LD_imm64 relocation
R_BPF_64_32 for call insn relocation
The existing R_BPF_64_64/R_BPF_64_32 mapping to numeric values
is maintained. They are the most common use cases for
bpf programs and we want to maintain backward compatibility
as much as possible.
ExecutionEngine RuntimeDyld BPF relocations are adjusted as well.
R_BPF_64_{ABS64,ABS32} relocations will be resolved properly and
other relocations will be ignored.
Two tests are added for RuntimeDyld. Not handling R_BPF_64_NODYLD32 in
RuntimeDyldELF.cpp will result in "Relocation type not implemented yet!"
fatal error.
FK_SecRel_4 usages in BPFAsmBackend.cpp and BPFELFObjectWriter.cpp
are removed as they are not triggered in BPF backend.
BPF backend used FK_SecRel_8 for LD_imm64 instruction operands.
Differential Revision: https://reviews.llvm.org/D102712
This patch introduces new operations on jitlink::Blocks: setMutableContent,
getMutableContent and getAlreadyMutableContent. The setMutableContent method
will set the block content data and size members and flag the content as
mutable. The getMutableContent method will return a mutable copy of the existing
content value, auto-allocating and populating a new mutable copy if the existing
content is marked immutable. The getAlreadyMutableMethod asserts that the
existing content is already mutable and returns it.
setMutableContent should be used when updating the block with totally new
content backed by mutable memory. It can be used to change the size of the
block. The argument value should *not* be shared with any other block.
getMutableContent should be used when clients want to modify the existing
content and are unsure whether it is mutable yet.
getAlreadyMutableContent should be used when clients want to modify the existing
content and know from context that it must already be immutable.
These operations reduce copy-modify-update boilerplate and unnecessary copies
introduced when clients couldn't me sure whether the existing content was
mutable or not.
The implementation and intent behind freeing the triple string here is the same
as LLVMGetDefaultTargetTriple (and any other owned c string returned from the C
API), so we should use LLVMDisposeMessage for to free the string for
consistency.
Patch by Mats Larsen -- thanks Mats!
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D102957
This patch introduces functionality used by BOLT when
re-linking the final binary. It adds to MemoryManager a new member
function allowStubAllocation to control whether this MemoryManager
supports increasing code size with stubs or not. Since BOLT can
rewrite some files in-place, it needs to avoid stub insertion done
by the linker. This patch also introduces allowsZeroSymbols to the
JITSymbolResolver class, enabling us to finish a link successfully
even when some symbols resolve to the value zero. When rewriting a
binary, sometimes we do need to resolve a target to zero in case
the input binary calls address zero and we want to be bug
compatible. We also expose reassignSectionAddress as it is used by
BOLT.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D97898
Fix was implemented in the ittap repo to solve an error about cross-compiling ITTAPI in LLVM with mingw.
The problem occurred in the cross-compilation environment for Julia's dependencies.
The corresponding issue item in ittapi repo: https://github.com/intel/ittapi/issues/19
A new tag was created in ittapi repo for that fix.
This patch contains changes to update the ittapi tag in LLVM.
Reviewed By: bader
Differential Revision: https://reviews.llvm.org/D102471
This is separate from (but builds on) the support added in ec6b71df70a for
emitting LinkGraphs in the context of an active materialization. This commit
makes LinkGraphs a first-class data structure with features equivalent to
object files within ObjectLinkingLayer.
These can be used to create eh-frame section fixing passes outside the usual
linker pipeline, which can be useful for tests and tools that just want to
verify or dump graphs.
This commit reorders some fields and fixes the width of others to try to
maintain more consistent columns. It also switches to long-hand scope
and linkage names, since LinkGraph dumps aren't read often enough for
single-character codes to be memorable.
Generalizing this API allows work to be distributed more evenly. In particular,
query callbacks can now be dispatched (rather than running immediately on the
thread that satisfied the query). This avoids the pathalogical case where an
operation on one thread satisfies many queries simultaneously, causing large
amounts of work to be run on that thread while other threads potentially sit
idle.
This can be useful for clients constructing custom JIT stacks: If the C API
for your custom stack exposes API to obtain a reference to an object layer
(e.g. LLVMOrcLLJITGetObjLinkingLayer) then the newly added
LLVMOrcObjectLayerAddObjectFile and LLVMOrcObjectLayerAddObjectFileWithRT
functions can be used to add objects directly to that layer.
This reapplies 8740360093b, which was reverted in bbddadd46e4 due to buildbot
errors.
This version checks that a JIT instance can be safely constructed, skipping
tests if it can not be. To enable this it introduces new C API to retrieve and
set the target triple for a JITTargetMachineBuilder.
Adds support for creating custom MaterializationUnits in the C API with the new
LLVMOrcCreateCustomMaterializationUnit function.
Modifies ownership rules for LLVMOrcAbsoluteSymbols to make it consistent with
LLVMOrcCreateCustomMaterializationUnit. This is an ABI breaking change for any
clients of the LLVMOrcAbsoluteSymbols API.
Adds LLVMOrcLLJITGetObjLinkingLayer and LLVMOrcObjectLayerEmit functions to
allow clients to get a reference to an LLJIT instance's linking layer, then
emit an object file using it. This can be used to support construction of
custom materialization units in the common case where those units will
generate an object file that needs to be emitted to complete the
materialization.
In EHFrameRegistrationPlugin::notifyTransferringResources if SrcKey had
eh-frames associated but DstKey did not we would create a new entry for DskKey,
invalidating the iterator for SrcKey in the process. This commit fixes that by
removing SrcKey first in this case.
It used to be that all of our intrinsics were call instructions, but over time, we've added more and more invokable intrinsics. According to the verifier, we're up to 8 right now. As IntrinsicInst is a sub-class of CallInst, this puts us in an awkward spot where the idiomatic means to check for intrinsic has a false negative if the intrinsic is invoked.
This change switches IntrinsicInst from being a sub-class of CallInst to being a subclass of CallBase. This allows invoked intrinsics to be instances of IntrinsicInst, at the cost of requiring a few more casts to CallInst in places where the intrinsic really is known to be a call, not an invoke.
After this lands and has baked for a couple days, planned cleanups:
Make GCStatepointInst a IntrinsicInst subclass.
Merge intrinsic handling in InstCombine and use idiomatic visitIntrinsicInst entry point for InstVisitor.
Do the same in SelectionDAG.
Do the same in FastISEL.
Differential Revision: https://reviews.llvm.org/D99976
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. ;)
This option tells LLJIT to disable platform support explicitly: JITDylibs aren't scanned for special init/deinit symbols and no runtime API interposes are injected.
It's useful in two cases: for platforms that don't have such requirements and platforms for which we have no explicit support yet and that don't work well with the generic IR platform.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D99416
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
Introduces DefineExternalSectionStartAndEndSymbols.h, which defines a template
for a JITLink pass that transforms external symbols meeting a user-supplied
predicate into defined symbols pointing at the start and end of a Section
identified by the predicate. JITLink.h is updated with a new makeAbsolute
function to support this pass.
Also renames BasicGOTAndStubsBuilder to PerGraphGOTAndPLTStubsBuilder -- the new
name better describes the intent of this GOT and PLT stubs builder, and will
help to distinguish it from future GOT and PLT stub builders that build entries
that may be shared between multiple graphs.
Issuing a lookup for an empty symbol set is legal, but can actually result in
unrelated work being done if there was a work queue left over from the previous
lookup. We can avoid doing this unrelated work (reducing stack depth and
interleaving of debugging output) by not issuing these no-op lookups in the
first place.
This patch introduces generic x86-64 edge kinds, and refactors the MachO/x86-64
backend to use these edge kinds. This simplifies the implementation of the
MachO/x86-64 backend and makes it possible to write generic x86-64 passes and
utilities.
The new edge kinds are different from the original set used in the MachO/x86-64
backend. Several edge kinds that were not meaningfully distinguished in that
backend (e.g. the PCRelMinusN edges) have been merged into single edge kinds in
the new scheme (these edge kinds can be reintroduced later if we find a use for
them). At the same time, new edge kinds have been introduced to convey extra
information about the state of the graph. E.g. The Request*AndTransformTo**
edges represent GOT/TLVP relocations prior to synthesis of the GOT/TLVP
entries, and the 'Relaxable' suffix distinguishes edges that are candidates for
optimization from edges which should be left as-is (e.g. to enable runtime
redirection).
ELF/x86-64 will be refactored to use these generic edges at some point in the
future, and I anticipate a similar refactor to create a generic arm64 support
header too.
Differential Revision: https://reviews.llvm.org/D98305
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.