This re-applies 570ecdcf8b4, which was reverted in 74e8a37ff32 due to bot
failures. This commit renames sysv_resolve.cpp to resolve.cpp, which was the
cause of the config errors.
This reapplies 570ecdcf8b4, which was reverted in 6073dd923b8 due to bot
failures.
The test failures on Linux were fixed by:
1. Removing an overly restrictive assertion (query dependence on a symbol no
longer implies a MaterializingInfo for that symbol)
2. Adding reentry and resolver files to the ORC runtime CMakeLists.txt for
Linux.
3. Adding the __orc_rt_reentry -> __orc_rt_sysv_reentry alias to ELFNixPlatform.
…d reentry.
These utilities provide new, more generic and easier to use support for
lazy compilation in ORC.
LazyReexportsManager is an alternative to LazyCallThroughManager. It
takes requests for lazy re-entry points in the form of an alias map:
lazy-reexports = {
( <entry point symbol #1>, <implementation symbol #1> ),
( <entry point symbol #2>, <implementation symbol #2> ),
...
( <entry point symbol #n>, <implementation symbol #n> )
}
LazyReexportsManager then:
1. binds the entry points to the implementation names in an internal
table.
2. creates a JIT re-entry trampoline for each entry point.
3. creates a redirectable symbol for each of the entry point name and
binds redirectable symbol to the corresponding reentry trampoline.
When an entry point symbol is first called at runtime (which may be on
any thread of the JIT'd program) it will re-enter the JIT via the
trampoline and trigger a lookup for the implementation symbol stored in
LazyReexportsManager's internal table. When the lookup completes the
entry point symbol will be updated (via the RedirectableSymbolManager)
to point at the implementation symbol, and execution will proceed to the
implementation symbol.
Actual construction of the re-entry trampolines and redirectable symbols
is delegated to an EmitTrampolines functor and the
RedirectableSymbolsManager respectively.
JITLinkReentryTrampolines.h provides a JITLink-based implementation of
the EmitTrampolines functor. (AArch64 only in this patch, but other
architectures will be added in the near future).
Register state save and reentry functionality is added to the ORC
runtime in the __orc_rt_sysv_resolve and __orc_rt_resolve_implementation
functions (the latter is generic, the former will need custom
implementations for each ABI and architecture to be supported, however
this should be much less effort than the existing OrcABISupport
approach, since the ORC runtime allows this code to be written as native
assembly).
The resulting system:
1. Works equally well for in-process and out-of-process JIT'd code.
2. Requires less boilerplate to set up.
Given an ObjectLinkingLayer and PlatformJD (JITDylib containing the ORC
runtime), setup is just:
```c++
auto RSMgr = JITLinkRedirectableSymbolManager::Create(OLL);
if (!RSMgr)
return RSMgr.takeError();
auto LRMgr = createJITLinkLazyReexportsManager(OLL, **RSMgr, PlatformJD);
if (!LRMgr)
return LRMgr.takeError();
```
after which lazy reexports can be introduced with:
```c++
JD.define(lazyReexports(LRMgr, <alias map>));
```
LazyObectLinkingLayer is updated to use this new method, but the LLVM-IR
level CompileOnDemandLayer will continue to use LazyCallThroughManager
and OrcABISupport until the new system supports a wider range of
architectures and ABIs.
The llvm-jitlink utility's -lazy option now uses the new scheme. Since
it depends on the ORC runtime, the lazy-link.ll testcase and associated
helpers are moved to the ORC runtime.
Adds two new JITLink passes to create and populate a pointer-signing function
that can be called via an allocation-action attached to the LinkGraph:
* createEmptyPointerSigningFunction creates a pointer signing function in a
custome section, reserving sufficient space for the signing code. It should
be run as a post-prune pass (to ensure that memory is reserved prior to
allocation).
* lowerPointer64AuthEdgesToSigningFunction pass populates the signing function
by walking the graph, decoding the ptrauth info (encoded in the edge addend) and
writing an instruction sequence to sign all ptrauth fixup locations.
rdar://61956998
This relocation is used in order to address GOT entries using 15 bit
offset in ldr instruction. The offset is calculated relative to GOT
section page address.
This relocation is used for the 14-bit immediate in test and branch
instructions.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D150778
This relocation is used for the 19-bit immediate in conditional branch
and compare and branch instructions.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D149138
Updates the aarch64 pointer jump stub sequence to:
ADRP x16, <ptr>@page21
LDR x16, [x16, <ptr>@pageoff12]
BR x16
from:
LDR x16, <ptr>@ldrimm19
BR x16
The old sequence can only reference pointers within +/-1Mb, which may not be
enough for large object files. The new sequence can reach pointers within
+/-4Gb. (A future pre-fixup-pass could apply range-based optimizations to
turn this into an ldr-br-nop sequence.)
Also adds createPointerJumpStubBlock and createAnonymousPointerJumpStub
utilities along the same lines as their x86-64 counterparts.
The PLTTableManager is updated to use the new utility functions.
This brings the aarch64 edges into alignment with the naming scheme for the
x86-64 edges.
Edge behavior is mostly unchanged, but some irrelevant assertions and errors
have been removed.
Pointer64Anon was lifted out of the MachO backend and into aarch64.h when that
header was created, but Pointer64Anon is really a MachO-specific "normalized"
relocation value, rather than a generic Edge::Kind. Any uses can be safely
replaced with Pointer64.
(Side note: the role of MachOPointer64Anon is to aid MachO relocation parsing:
For MachOPointer64, the target symbol is specified by the r_symbolnum field in
the relocation. For MachOPointer64Anon the address of the anonymous target is
read from the fixup location.)
Adds a generic utility for creating anonymous aarch64 pointer blocks
(automatically adding an edge to initialize the pointer if given an
initial target).
Updates the aarch64 GOTTableManager to use the utility when building
GOT entries.
PointerToGOT lowering was accidentally changed from Delta32 to Delta64 in
db3722580335c. This patch moves it back to Delta32 and renames the generic
aarch64 edge to Delta32ToGOT to avoid the ambiguity.
No test case yet -- I haven't figured out how to write a succinct test case
(this typically appears in CIEs in eh-frames).
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
Implements MoveWide16 generic edge kind that can be used to patch MOVZ/MOVK (imm16) instructions.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D127584
Lift fixup functions from aarch64.cpp to aarch64.h so that they have better chance of getting inlined. Also, adds some comments documenting the purpose of functions.
Reviewed By: sgraenitz
Differential Revision: https://reviews.llvm.org/D127559
Unifies GOT/PLT table managers of ELF and MachO on aarch64 architecture. Additionally, it migrates table managers from PerGraphGOTAndPLTStubsBuilder to generic crtp TableManager.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D127558
The separate isLoadStoreImm12 predicate will be used for validating ELF/aarch64
ldst relocation types.
Reviewed By: lhames, sgraenitz
Differential Revision: https://reviews.llvm.org/D126628
This patch moves the aarch64 fixup logic from the MachO/arm64 backend to
aarch64.h header so that it can be re-used in the ELF/aarch64 backend. This
significantly expands relocation support in the ELF/aarch64 backend.
Reviewed By: lhames, sgraenitz
Differential Revision: https://reviews.llvm.org/D126286
Set up basic infrastructure for 64-bit ARM architecture support in JITLink. It allows for loading a minimal object file and resolving a single relocation. Advanced features like GOT and PLT handling or relaxations were intentionally left out for the moment.
This patch follows the idea to keep implementations for ARM (32-bit) and Aaarch64 (64-bit) separate, because:
* it might be easier to share code with the MachO "arm64" JITLink backend
* LLVM has individual targets for ARM and Aaarch64 as well
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D108986
