Commit Graph

549 Commits

Author SHA1 Message Date
Lang Hames fc36a511c6 [JITLink][ELF/x86-64] Add support for R_X86_64_GOTPC64 and R_X86_64_GOT64.
Start adding support for ELF x86-64 large code model, PIC relocations.
2021-03-21 21:52:54 -07:00
Lang Hames 1237d94871 [JITLink] Add support for STT_NOTYPE symbols to ELF/x86-64. 2021-03-09 20:40:24 -08:00
Stefan Gränitz 6a3a386c6f [Orc] Test DebugObjectManagerPlugin fills in load-address for .text section of in-memory ELF debug object 2021-03-09 14:01:50 +01:00
Stefan Gränitz ae51fde369 [Orc] Extend lli debug support tests to JITLink 2021-03-02 15:07:36 +01:00
Stefan Gränitz f47ff8cff1 [lli] Test debug support in RuntimeDyld with built-in functions
When lli runs the below IR, it emits in-memory debug objects and registers them with the GDB JIT interface. The tests dump and check the registered information. IR has limited ability to produce complex output in a portable way. Instead the tests rely on built-in functions implemented in lli. They use a new command line flag `-generate=function-name` to instruct the ORC JIT to expose the built-in function with the given name to the JITed program.

`debug-descriptor-elf-minimal.ll` calls `__dump_jit_debug_descriptor()` to reflect the list of debug entries issued for itself after emitting the main module. The output is textual and can be checked straight away.

`debug-objects-elf-minimal.ll` calls `__dump_jit_debug_objects()`, which instructs lli to walk through the list of debug entries and append the encountered in-memory objects to the program output. We feed this output into llvm-dwarfdump to parse the DWARF in each file and dump their structures.

We can do the same for JITLink once D97335 has landed.

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D97694
2021-03-02 10:39:09 +01:00
Lang Hames d2bb07949b Revert "[JITLink] Add missing symbols for ELF ehframe testcase, re-enable ...."
This reverts commit 6e58539659.

This failed in http://lab.llvm.org:8011/#/builders/123/builds/2676. I guess
were're still missing some symbols, but unfortunately the specific error is
masked by a bug in python/lit that hides stderr. This test will have to remain
disabled on Windows until I can get help to debug it further.
2021-02-01 13:32:11 +11:00
Lang Hames 6e58539659 [JITLink] Add missing symbols for ELF ehframe testcase, re-enable on Windows.
This testcase was failing on windows due to missing definitions. This commit
adds definitions of the missing symbols (as absolute symbols) to eliminate the
errors.
2021-02-01 12:24:24 +11:00
Lang Hames 236b0d0407 [JITLink] Disable ELF_ehframe_basic.s test on Windows.
This test is failing on some windows bots with an error claiming that it is not
producing output. This appears to be a spurious failure, so I'm disabling on
windows while we investigate rather than reverting.
2021-01-26 13:58:38 +11:00
Lang Hames cda4d3d37f [JITLink] Re-apply 6884fbc2c4 (ELF eh support) with fix for broken test case. 2021-01-26 11:55:41 +11:00
Nico Weber f80782590c Revert "[JITLink] Enable exception handling for ELF."
This reverts commit 6884fbc2c4.
Breaks tests on Windows: http://45.33.8.238/win/31981/step_11.txt
2021-01-25 11:00:38 -05:00
Lang Hames 6884fbc2c4 [JITLink] Enable exception handling for ELF.
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.
2021-01-25 15:31:27 +11:00
Lang Hames 3b1f17ca54 [JITLink][ELF/x86-64] Add support for weak and hidden symbols. 2021-01-22 20:51:11 +11:00
Lang Hames e5619065b8 [JITLink][ELF] New ELF skip-debug-sections test requires asserts.
This should fix the failures on Release mode testers.
2021-01-18 15:41:53 +11:00
Lang Hames a817f46d50 [JITLink][ELF] Skip DWARF sections in ELF objects.
This matches current JITLink/MachO behavior and avoids processing currently
unsupported relocations.
2021-01-18 12:42:48 +11:00
Stefan Gränitz 694c16a823 [JITLink][ELF] Omit temporary labels in tests
Oneshot temporary labels for declaring function size can be omitted. Follow-up from D90331.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D90676
2020-11-04 10:03:15 +00:00
Stefan Gränitz b397795f1a [JITLink][ELF] Implement R_X86_64_PLT32 relocations
Basic implementation for call and jmp branches with 32 bit offset. Branches to local targets produce
Branch32 edges that are resolved like a regular PCRel32 relocations. Branches to external (undefined)
targets produce Branch32ToStub edges and go through a PLT entry by default. If the target happens to
get resolved within the 32 bit range from the callsite, the edge is relaxed during post-allocation
optimization. There is a test for each of these cases.

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D90331
2020-11-03 12:05:54 +00:00
Stefan Gränitz 66abe650ff Reapply "[jitlink][ELF] Add zero-fill blocks for symbols in section SHN_COMMON"
Root cause of the test failure was fixed with:
[JITLink][ELF] PCRel32GOTLoad edge offset can be smaller three

This reverts commit 10b1a61baf.
2020-10-24 16:58:06 +02:00
Stefan Gränitz 10b1a61baf Revert "[jitlink][ELF] Add zero-fill blocks for symbols in section SHN_COMMON"
This reverts commit e9955b0843. Cannot reproduce the buildbot failures yet. Reverting in the meantime.
2020-10-24 15:43:06 +02:00
Stefan Gränitz e9955b0843 [jitlink][ELF] Add zero-fill blocks for symbols in section SHN_COMMON
Symbols with special section index SHN_COMMON (0xfff2) haven't been handled so far and caused an invalid section error.

This is a more or less straightforward use of the code commented out at the end of the function. I checked with the ELF spec, that the symbol value gives the alignment.

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D89795
2020-10-24 14:54:38 +02:00
Lang Hames 996a8b42aa Re-apply "[JITLink][ELF] Add support for ELF::R_X86_64_REX_GOTPCRELX relocation"
This re-applies e2fceec2fd with fixes. Apparently we already *do* support
relaxation for ELF, so we need to make sure the test case allocates a slab at
a fixed address, and that the R_X86_64_REX_GOTPCRELX test references an external
that is guaranteed to be out of range.
2020-10-23 09:48:05 -07:00
Lang Hames 0f910387e6 Revert "[JITLink][ELF] Add support for ELF::R_X86_64_REX_GOTPCRELX relocation."
This reverts commit e2fceec2fd.

This commit broke one of the bots. Reverting while I investigate.
2020-10-22 23:21:29 -07:00
Lang Hames e2fceec2fd [JITLink][ELF] Add support for ELF::R_X86_64_REX_GOTPCRELX relocation.
No support for relaxation yet -- this will always use the GOT entry.
2020-10-22 22:43:16 -07:00
Lang Hames 6154c4115c [ORC] Remove OrcV1 APIs.
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.
2020-10-18 21:02:44 -07:00
Lang Hames 01baeda7ca [JITLink][ELF] Handle BSS sections, improve some error messages.
This patch enables basic BSS section handling, and improves a couple of error
messages in the ELF section parsing code.

Patch by Christian Schafmeister. Thanks Christian!

Differential Revision: https://reviews.llvm.org/D88867
2020-10-05 21:35:35 -07:00
Lang Hames a49b05bb61 [JITLink][MachO] Use correct symbol scope when N_PEXT is set and N_EXT unset.
MachOLinkGraphBuilder has been treating these as hidden, but they should be
treated as local.

Symbols with N_PEXT set and N_EXT unset are produced when hidden symbols are
run through 'ld -r' without passing -keep_private_externs. They will show up
under 'nm -m' as "was private extern", hence the name of the test cases.

Testcase commited as relocatable object to ensure that the test suite doesn't
depend on having 'ld -r' available.
2020-08-15 15:53:33 -07:00
Lang Hames ba8683f292 [JITLink][MachO][AArch64] More PAGEOFF12 relocation fixes.
Correctly sign extend the addend, and fix implicit shift operand decoding
(it incorrectly returned 0 for some cases), and check that the initial
encoded immediate is 0.
2020-08-05 21:09:45 -07:00
Lang Hames 47cfffe893 [JITLink][AArch64] Handle addends on PAGE21 / PAGEOFF12 relocations. 2020-08-05 08:50:46 -07:00
Lang Hames 0f5b70769d [llvm-jitlink] Add -phony-externals option to suppress unresolved externals.
The -phony-externals option adds a generator which explicitly defines any
otherwise unresolved externals as null. This transforms link-time
unresolved-symbol errors into potential runtime null pointer accesses
(if an unresolved external is actually accessed during execution).

This option can be useful in -harness mode to avoid having to mock a
large number of symbols that are not reachable at runtime (e.g. unused
methods referenced by a class vtable).
2020-08-01 18:33:44 -07:00
Lang Hames e12a028ed3 [llvm-jitlink] Support promotion of ODR weak symbols in -harness mode.
This prevents weak symbols from being immediately dead-stripped when not
directly referenced from the test harneess, enabling use of weak symbols
from the code under test.
2020-08-01 18:33:44 -07:00
Lang Hames 8ce8cee1e1 [llvm-jitlink] Add -harness option to llvm-jitlink.
The -harness option enables new testing use-cases for llvm-jitlink. It takes a
list of objects to treat as a test harness for any regular objects passed to
llvm-jitlink.

If any files are passed using the -harness option then the following
transformations are applied to all other files:

  (1) Symbols definitions that are referenced by the harness files are promoted
      to default scope. (This enables access to statics from test harness).

  (2) Symbols definitions that clash with definitions in the harness files are
      deleted. (This enables interposition by test harness).

  (3) All other definitions in regular files are demoted to local scope.
      (This causes untested code to be dead stripped, reducing memory cost and
      eliminating spurious unresolved symbol errors from untested code).

These transformations allow the harness files to reference and interpose
symbols in the regular object files, which can be used to support execution
tests (including fuzz tests) of functions in relocatable objects produced by a
build.
2020-07-30 15:26:19 -07:00
Jared Wyles b847859f37 [jitlink] Updating test file for GOT relocations for elf x86 2020-07-21 17:19:48 +10:00
James Henderson 908804b093 [test][llvm-readobj] Fix build bot failure after df952cb9
The test wasn't updated due to being an unusual target not included in
my test run.
2020-07-20 11:23:13 +01:00
Lang Hames f7a571537a [JITLink][MachO] Fix handling of non-extern UNSIGNED pair of SUBTRACTOR relocs.
When processing a MachO SUBTRACTOR/UNSIGNED pair, if the UNSIGNED target
is non-extern then check the r_symbolnum field of the relocation to find
the targeted section and use the section's address to find 'ToSymbol'.

Previously 'ToSymbol' was found by loading the initial value stored at
the fixup location and treating this as an address to search for. This
is incorrect, however: the initial value includes the addend and will
point to the wrong block if the addend is less than zero or greater than
the block size.

rdar://65756694
2020-07-19 10:22:55 -07:00
Jared Wyles ef454c5444 [jitlink] Adding support for PCRel32GOTLoad in ELF x86 for the jitlinker
Summary: This adds the basic support for GOT in elf x86.
Was able to just get away using the macho code by generalising the edges.
There will be a follow up patch to turn that into a generic utility for both of the x86 and Mach-O code.

This patch also lands support for relocations relative to symbol.

Reviewers: lhames

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83748
2020-07-16 07:15:08 +10:00
Fangrui Song bdc3134e23 [RuntimeDyld][test] Fix ExecutionEngine/RuntimeDyld/X86/ELF_x86-64_none.yaml after D60122
*.yaml tests don't currently run, so we failed to notice it.
2020-07-07 15:05:50 -07:00
Lang Hames 22d7a01dd7 [JITLink] Allow zero-length symbols at the end of blocks.
This relaxes an assertion that required symbols to start before the end
of a block. Instead, symbols are now required to end on or before the
end of a block. This fixes two important corner cases: Symbols at the
start of empty blocks/sections, and block/section end symbols.
2020-06-19 10:05:02 -07:00
Lang Hames 498dd745f5 [ORC] Honor linker private global prefix on symbol names.
If a symbol name begins with the linker private global prefix (as
described by the DataLayout) then it should be treated as non-exported,
regardless of its LLVM IR visibility value.
2020-06-15 10:28:36 -07:00
Lang Hames d27cbf03cf [JITLink] Skip debug sections in MachO objects.
Debug sections will not be linked into the final executable and may contain
ambiguous relocations*. Skipping them avoids both some unnecessary processing
cost and the hassle of dealing with the problematic relocations.

* E.g. __debug_ranges contains non-extern relocations to the end of functions
hat begin with named symbols. Under the usual rules for interpreting non-extern
relocations these will be incorrectly associated with the following block, or
no block at all (if there is a gap between one block and the next).
2020-06-03 11:08:14 -07:00
Jared Wyles 3f0841f6d0 [jitlink] R_X86_64_PC32 support for the elf x86 jitlinker
Summary:

Adding in our first relocation type, and all the required plumbing to support the rest in following patches

Differential Revision: https://reviews.llvm.org/D80613

Reviewer: lhames
2020-05-30 10:53:18 +10:00
Serge Pavlov 4d20e31f73 [FPEnv] Intrinsic llvm.roundeven
This intrinsic implements IEEE-754 operation roundToIntegralTiesToEven,
and performs rounding to the nearest integer value, rounding halfway
cases to even. The intrinsic represents the missed case of IEEE-754
rounding operations and now llvm provides full support of the rounding
operations defined by the standard.

Differential Revision: https://reviews.llvm.org/D75670
2020-05-26 19:24:58 +07:00
Lang Hames 2e40cf06df [JITLink] Initial implementation of ELF / x86-64 support for JITLink.
This initial implementation supports section and symbol parsing, but no
relocation support. It enables JITLink to link and execute ELF relocatable
objects that do not require relocations.

Patch by Jared Wyles. Thanks Jared!

Differential Revision: https://reviews.llvm.org/D79832
2020-05-21 21:44:00 -07:00
Hans Wennborg 64c2312750 Revert 43f031d312 "Enable IBT(Indirect Branch Tracking) in JIT with CET(Control-flow Enforcement Technology)"
ExecutionEngine/MCJIT/cet-code-model-lager.ll is failing on 32-bit
windows, see llvm-commits thread for fef2dab.

This reverts commit 43f031d312
and the follow-ups fef2dab100 and
6a800f6f62.
2020-04-06 15:05:25 +02:00
Hans Wennborg 6a800f6f62 Add a triple to test/ExecutionEngine/MCJIT/cet-code-model-lager.ll
It was failing in 32-bit Windows builds with:

  $ ":" "RUN: at line 1"
  $ "c:\src\llvm_package_944db8a4\build32_stage0\bin\lli.exe" "-mtriple=i686-pc-windows-msvc-elf" "-code-model=large" "C:\src\llvm_package_944db8a4\llvm-project\llvm\test\ExecutionEngine\MCJIT\cet-code-model-lager.ll"
  # command stderr:
  Assertion failed: Is64Bit && "Large code model is only legal in 64-bit mode.", file C:\src\llvm_package_944db8a4\llvm-project\llvm\lib\Target\X86\X86ISelLowering.cpp, line 4212

Let's see if this helps.
2020-04-06 14:19:59 +02:00
Lang Hames 1b39c6f62c [ORC] Add MachO universal binary support to StaticLibraryDefinitionGenerator.
Add a new overload of StaticLibraryDefinitionGenerator::Load that takes a triple
argument and supports loading archives from MachO universal binaries in addition
to regular archives.

The LLI tool is updated to use this overload.
2020-04-05 20:21:05 -07:00
Xiang1 Zhang fef2dab100 Bugix for buildbot failure at commit 43f031d312
Author: Xiang1 Zhang <xiang1.zhang@intel.com>
Date:   Fri Apr 3 11:25:38 2020 +0800

    Enable IBT(Indirect Branch Tracking) in JIT with CET(Control-flow Enforcement Technology)
2020-04-03 13:25:35 +08:00
Xiang1 Zhang 43f031d312 Enable IBT(Indirect Branch Tracking) in JIT with CET(Control-flow Enforcement Technology)
Summary:
This patch comes from H.J.'s 2bd54ce7fa

**This patch fix the failed llvm unit tests which running on CET machine. **(e.g. ExecutionEngine/MCJIT/MCJITTests)

The reason we enable IBT at "JIT compiled with CET" is mainly that:  the JIT don't know the its caller program is CET enable or not.
If JIT's caller program is non-CET, it is no problem JIT generate CET code or not.
But if JIT's caller program is CET enabled,  JIT must generate CET code or it will cause Control protection exceptions.

I have test the patch at llvm-unit-test and llvm-test-suite at CET machine. It passed.
and H.J. also test it at building and running VNCserver(Virtual Network Console), it works too.
(if not apply this patch, VNCserver will crash at CET machine.)

Reviewers: hjl.tools, craig.topper, LuoYuanke, annita.zhang, pengfei

Subscribers: tstellar, efriedma, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76900
2020-04-03 11:44:07 +08:00
Lang Hames 05598441de Re-apply 0071eaaf08, "[ORC] Export __cxa_atexit ...", with fixes.
Forgot to include part of the testcase. Thank to Nico for spotting that and
reverting!
2020-04-02 16:03:35 -07:00
Nico Weber 5bac8d427d Revert "[ORC] Export __cxa_atexit from the main JITDylib in LLJIT."
This reverts commit 0071eaaf08.
Inputs/noop-main.ll wasn't checked in, so this breaks check-llvm
everywhere.
2020-04-01 22:49:38 -04:00
Lang Hames 0071eaaf08 [ORC] Export __cxa_atexit from the main JITDylib in LLJIT.
Failure to export __cxa_atexit can lead to an attempt to import a definition
from the process itself (if __cxa_atexit is referenced from another JITDylib),
but the process definition will clash with the existing non-exported definition
to produce an unexpected DuplicateDefinitionError.

This patch fixes the immediate issue by exporting __cxa_atexit. It also fixes a
bug where atexit functions in other JITDylibs were not being run by adding a
copy of run_atexits_helper to every JITDylib.

A follow up patch will deal with the bug where definition generators are called
despite a non-exported definition being present.
2020-04-01 19:12:08 -07:00
Lang Hames 8e5a8f620c [ORC] Don't require a null-terminator on MemoryBuffers for objects in archives.
The MemoryBuffer::getMemBuffer method's RequiresNullTerminator parameter
defaults to true, but object files are not null terminated so we need to
explicitly pass false here.
2020-04-01 12:16:38 -07:00
Fangrui Song 71f8b78d89 [AsmPrinter] Simplify AsmPrinter::emitXXStructorList after D61547 2020-03-21 23:18:23 -07:00
Lang Hames 1e66710d39 [JITLink][AArch64] Fix incorrect capitalization in a testcase name. 2020-03-14 18:54:40 -07:00
Lang Hames 9c9eb60b4b [JITLink][MachO] Re-apply b64afadf30, MachO linker-private support, with fixes.
Global symbols with linker-private prefixes should be resolvable across object
boundaries, but internal symbols with linker-private prefixes should not.
2020-03-14 18:36:15 -07:00
Lang Hames a7d187d9c0 Revert "[JITLink][MachO] Treat linker private symbols as hidden rather than private."
This reverts commit b64afadf30.

Reverting while I investigate bot failures.
2020-03-14 16:52:25 -07:00
Lang Hames b64afadf30 [JITLink][MachO] Treat linker private symbols as hidden rather than private.
Linker-private symbols should be resolvable across object file boundaries.
2020-03-14 16:33:15 -07:00
Lang Hames 7266a8bfeb [ORC] Enable exception handling in JIT'd code when using LLJIT on Darwin.
This patch enables exception handling in code added to LLJIT on Darwin by
adding an orc::EHFrameRegistrationPlugin instance to the ObjectLinkingLayer
(which is currently used on Darwin only).
2020-03-12 15:33:56 -07:00
Lang Hames c700e0317c [JITLink] Read symbol linkage from the correct field.
MachO symbol linkage is described by the desc field of the nlist entry, not the
type field.
2020-03-11 20:04:54 -07:00
Lang Hames 337e131ca7 [RuntimeDyld][COFF] Build stubs for COFF dllimport symbols.
Summary:
Enables JIT-linking by RuntimeDyld of COFF objects that contain references to
dllimport symbols. This is done by recognizing symbols that start with the
reserved "__imp_" prefix and building a pointer entry to the target symbol in
the stubs area of the section. References to the "__imp_" symbol are updated to
point to this pointer.

Work in progress: The generic code is in place, but only RuntimeDyldCOFFX86_64
and RuntimeDyldCOFFI386 have been updated to look for and update references to
dllimport symbols.

Reviewers: compnerd

Subscribers: hiraditya, ributzka, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75884
2020-03-10 16:08:40 -07:00
Lang Hames 14ac84e5c5 [JITLink] Add a -slab-address option to llvm-jitlink.
This option can be used to for JITLink to link as-if the target memory slab were
allocated at a specific start address. This can be used to both verify that
cross-address space linking is working correctly, and to ensure that certain
address-sensitive optimizations (e.g. GOT and stub elimination) either do or do
not fire, depending on the requirements of the test case.

This argument is only valid for testing in conjunction with -noexec -slab-alloc,
and will produce an error if used without those arguments.
2020-03-03 14:25:51 -08:00
Lang Hames ff4fd8dead [ORC] Make sure we add initializers to the SymbolFlags map for objects. 2020-03-03 09:33:37 -08:00
Erik Pilkington 30f4362040 Disable memory leak checking in a test to work around a bot failure
This leak is expected, see the discussion on commit 85fb997
2020-02-26 14:51:50 -08:00
Lang Hames 27a79b7216 [JITLink] Add a MachO x86-64 GOT and Stub bypass optimization.
This optimization bypasses GOT loads and calls/branches through stubs when the
ultimate target of the access/branch is found to be within range of the
reference.

Extra debugging output is also added to the generic JITLink algorithm and
basic GOT and Stubs builder utility to aid debugging.
2020-02-23 23:38:31 -08:00
Lang Hames 1df947ab40 [ORC] Update LLJIT to automatically run specially named initializer functions.
The GenericLLVMIRPlatformSupport class runs a transform on all LLVM IR added to
the LLJIT instance to replace instances of llvm.global_ctors with a specially
named function that runs the corresponing static initializers (See
(GlobalCtorDtorScraper from lib/ExecutionEngine/Orc/LLJIT.cpp). This patch
updates the GenericIRPlatform class to check for this specially named function
in other materialization units that are added to the JIT and, if found, add
the function to the initializer work queue. Doing this allows object files
that were compiled from IR and cached to be reloaded in subsequent JIT sessions
without their initializers being skipped.

To enable testing this patch also updates the lli tool's -jit-kind=orc-lazy mode
to respect the -enable-cache-manager and -object-cache-dir options, and modifies
the CompileOnDemandLayer to rename extracted submodules to include a hash of the
names of their symbol definitions. This allows a simple object caching scheme
based on module names (which was already implemented in lli) to work with the
lazy JIT.
2020-02-22 11:49:14 -08:00
Lang Hames f5efa08247 [JITLink] Fix testcase for main JITDylib rename in 85fb997659. 2020-02-19 14:58:13 -08:00
Lang Hames 85fb997659 [ORC] Add generic initializer/deinitializer support.
Initializers and deinitializers are used to implement C++ static constructors
and destructors, runtime registration for some languages (e.g. with the
Objective-C runtime for Objective-C/C++ code) and other tasks that would
typically be performed when a shared-object/dylib is loaded or unloaded by a
statically compiled program.

MCJIT and ORC have historically provided limited support for discovering and
running initializers/deinitializers by scanning the llvm.global_ctors and
llvm.global_dtors variables and recording the functions to be run. This approach
suffers from several drawbacks: (1) It only works for IR inputs, not for object
files (including cached JIT'd objects). (2) It only works for initializers
described by llvm.global_ctors and llvm.global_dtors, however not all
initializers are described in this way (Objective-C, for example, describes
initializers via specially named metadata sections). (3) To make the
initializer/deinitializer functions described by llvm.global_ctors and
llvm.global_dtors searchable they must be promoted to extern linkage, polluting
the JIT symbol table (extra care must be taken to ensure this promotion does
not result in symbol name clashes).

This patch introduces several interdependent changes to ORCv2 to support the
construction of new initialization schemes, and includes an implementation of a
backwards-compatible llvm.global_ctor/llvm.global_dtor scanning scheme, and a
MachO specific scheme that handles Objective-C runtime registration (if the
Objective-C runtime is available) enabling execution of LLVM IR compiled from
Objective-C and Swift.

The major changes included in this patch are:

(1) The MaterializationUnit and MaterializationResponsibility classes are
extended to describe an optional "initializer" symbol for the module (see the
getInitializerSymbol method on each class). The presence or absence of this
symbol indicates whether the module contains any initializers or
deinitializers. The initializer symbol otherwise behaves like any other:
searching for it triggers materialization.

(2) A new Platform interface is introduced in llvm/ExecutionEngine/Orc/Core.h
which provides the following callback interface:

  - Error setupJITDylib(JITDylib &JD): Can be used to install standard symbols
    in JITDylibs upon creation. E.g. __dso_handle.

  - Error notifyAdding(JITDylib &JD, const MaterializationUnit &MU): Generally
    used to record initializer symbols.

  - Error notifyRemoving(JITDylib &JD, VModuleKey K): Used to notify a platform
    that a module is being removed.

  Platform implementations can use these callbacks to track outstanding
initializers and implement a platform-specific approach for executing them. For
example, the MachOPlatform installs a plugin in the JIT linker to scan for both
__mod_inits sections (for C++ static constructors) and ObjC metadata sections.
If discovered, these are processed in the usual platform order: Objective-C
registration is carried out first, then static initializers are executed,
ensuring that calls to Objective-C from static initializers will be safe.

This patch updates LLJIT to use the new scheme for initialization. Two
LLJIT::PlatformSupport classes are implemented: A GenericIR platform and a MachO
platform. The GenericIR platform implements a modified version of the previous
llvm.global-ctor scraping scheme to provide support for Windows and
Linux. LLJIT's MachO platform uses the MachOPlatform class to provide MachO
specific initialization as described above.

Reviewers: sgraenitz, dblaikie

Subscribers: mgorny, hiraditya, mgrang, ributzka, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74300
2020-02-19 13:59:32 -08:00
Lang Hames ca6f58486f [ORC] Fix symbol dependence propagation algorithm in ObjectLinkingLayer.
ObjectLinkingLayer was not correctly propagating dependencies through local
symbols within an object. This could cause symbol lookup to return before a
searched-for symbol is ready if the following conditions are met:
(1) The definition of the symbol being searched for transitively depends on a
    local symbol within the same object, and that local symbol in turn
    transitively depends on an external symbol provided by some other module
    in the JIT.
(2) Concurrent compilation is enabled.
(3) Thread scheduling causes the lookup of the searched-for symbol to return
    before all transitive dependencies of the looked-up symbol are emitted.

This bug was found by inspection and has not been observed in practice.

A jitlink test case has been added to verify that symbol dependencies are
correctly propagated through local symbol definitions.
2020-02-11 12:56:41 -08:00
Lang Hames ce2207abaf [ORC] Add support for emulated TLS to ORCv2.
This commit adds a ManglingOptions struct to IRMaterializationUnit, and replaces
IRCompileLayer::CompileFunction with a new IRCompileLayer::IRCompiler class. The
ManglingOptions struct defines the emulated-TLS state (via a bool member,
EmulatedTLS, which is true if emulated-TLS is enabled and false otherwise). The
IRCompileLayer::IRCompiler class wraps an IRCompiler (the same way that the
CompileFunction typedef used to), but adds a method to return the
IRCompileLayer::ManglingOptions that the compiler will use.

These changes allow us to correctly determine the symbols that will be produced
when a thread local global variable defined at the IR level is compiled with or
without emulated TLS. This is required for ORCv2, where MaterializationUnits
must declare their interface up-front.

Most ORCv2 clients should not require any changes. Clients writing custom IR
compilers will need to wrap their compiler in an IRCompileLayer::IRCompiler,
rather than an IRCompileLayer::CompileFunction, however this should be a
straightforward change (see modifications to CompileUtils.* in this patch for an
example).
2020-01-21 19:55:33 -08:00
Lang Hames 2cdb18afda [ORC] Fix argv handling in runAsMain / lli.
This fixes an off-by-one error in the argc value computed by runAsMain, and
switches lli back to using the input bitcode (rather than the string "lli") as
the effective program name.

Thanks to Stefan Graenitz for spotting the bug.
2020-01-11 13:03:38 -08:00
Lang Hames d9220b580b [JITLink][MachO] Fix common symbol size plumbing.
This fixes the underlying bug that was exposed by 298e183e81.
2019-12-19 20:41:59 -08:00
Lang Hames 674df13b5f [ORC][JITLink] Add support for weak references, and improve handling of static
libraries.

This patch substantially updates ORCv2's lookup API in order to support weak
references, and to better support static archives. Key changes:

-- Each symbol being looked for is now associated with a SymbolLookupFlags
   value. If the associated value is SymbolLookupFlags::RequiredSymbol then
   the symbol must be defined in one of the JITDylibs being searched (or be
   able to be generated in one of these JITDylibs via an attached definition
   generator) or the lookup will fail with an error. If the associated value is
   SymbolLookupFlags::WeaklyReferencedSymbol then the symbol is permitted to be
   undefined, in which case it will simply not appear in the resulting
   SymbolMap if the rest of the lookup succeeds.

   Since lookup now requires these flags for each symbol, the lookup method now
   takes an instance of a new SymbolLookupSet type rather than a SymbolNameSet.
   SymbolLookupSet is a vector-backed set of (name, flags) pairs. Clients are
   responsible for ensuring that the set property (i.e. unique elements) holds,
   though this is usually simple and SymbolLookupSet provides convenience
   methods to support this.

-- Lookups now have an associated LookupKind value, which is either
   LookupKind::Static or LookupKind::DLSym. Definition generators can inspect
   the lookup kind when determining whether or not to generate new definitions.
   The StaticLibraryDefinitionGenerator is updated to only pull in new objects
   from the archive if the lookup kind is Static. This allows lookup to be
   re-used to emulate dlsym for JIT'd symbols without pulling in new objects
   from archives (which would not happen in a normal dlsym call).

-- JITLink is updated to allow externals to be assigned weak linkage, and
   weak externals now use the SymbolLookupFlags::WeaklyReferencedSymbol value
   for lookups. Unresolved weak references will be assigned the default value of
   zero.

Since this patch was modifying the lookup API anyway, it alo replaces all of the
"MatchNonExported" boolean arguments with a "JITDylibLookupFlags" enum for
readability. If a JITDylib's associated value is
JITDylibLookupFlags::MatchExportedSymbolsOnly then the lookup will only
match against exported (non-hidden) symbols in that JITDylib. If a JITDylib's
associated value is JITDylibLookupFlags::MatchAllSymbols then the lookup will
match against any symbol defined in the JITDylib.
2019-11-28 13:30:49 -08:00
Lang Hames c33598d5e5 [JITLink] Make sure MachO/x86-64 handles 32-bit signed addends correctly.
These need to be sign extended when loading into Edge addends.
2019-11-27 22:46:07 -08:00
Adam Kallai dc3ee33089 ExecutionEngine: add preliminary support for COFF ARM64
Differential Revision: https://reviews.llvm.org/D69434
2019-11-20 10:59:42 +02:00
Lang Hames 76aee8a389 [JITLink] Refactor EH-frame handling to support eh-frames with existing relocs.
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).
2019-11-06 14:30:26 -08:00
Lang Hames c85d0aaa2a [JITLink] Switch to slab allocation for InProcessMemoryManager, re-enable test.
InProcessMemoryManager used to make separate memory allocation calls for each
permission level (RW, RX, RO), which could lead to target-out-of-range errors
if data and code were placed too far apart (this was the source of failures in
the JITLink/AArch64 testcase when it was first landed).

This patch updates InProcessMemoryManager to allocate a single slab which is
subdivided between text and data. This should guarantee that accesses remain
in-range provided that individual object files do not exceed 1Mb in size.
This patch also re-enables the JITLink/AArch64 testcase.

llvm-svn: 374948
2019-10-15 21:06:57 +00:00
Lang Hames e5c61cee44 [JITLink] Disable the MachO/AArch64 testcase while investigating bot failures.
The windows bots are failing due to a memory layout error. Temporarily disabling
while I investigate whether this can be worked around, or whether the test
should be disabled on Windows.

llvm-svn: 374500
2019-10-11 01:58:12 +00:00
Lang Hames 3cc04f6a41 [JITLink] Add an initial implementation of JITLink for MachO/AArch64.
This implementation has support for all relocation types except TLV.

Compact unwind sections are not yet supported, so exceptions/unwinding will not
work.

llvm-svn: 374476
2019-10-10 23:37:51 +00:00
Lang Hames 96cd736c2d [JITLink] Move MachO/x86 got test further down in the data section.
'named_data' should be the first symbol in the data section.

llvm-svn: 374475
2019-10-10 23:37:49 +00:00
Lang Hames 4e920e58e6 [JITLink] Switch from an atom-based model to a "blocks and symbols" model.
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
2019-10-04 03:55:26 +00:00
Lang Hames 70e158e09e [JITLink] Don't under-align zero-fill sections.
If content sections have lower alignment than zero-fill sections then bump the
overall segment alignment to avoid under-aligning the zero-fill sections.

llvm-svn: 370072
2019-08-27 15:22:23 +00:00
Lang Hames 52a34a78d9 [ORC] Refactor definition-generation, add a generator for static libraries.
This patch replaces the JITDylib::DefinitionGenerator typedef with a class of
the same name, and adds support for attaching a sequence of DefinitionGeneration
objects to a JITDylib.

This patch also adds a new definition generator,
StaticLibraryDefinitionGenerator, that can be used to add symbols fom a static
library to a JITDylib. An object from the static library will be added (via
a supplied ObjectLayer reference) whenever a symbol from that object is
referenced.

To enable testing, lli is updated to add support for the --extra-archive option
when running in -jit-kind=orc-lazy mode.

llvm-svn: 368707
2019-08-13 16:05:18 +00:00
Lang Hames fe37499207 [JITLink] Fix an overly-wide read in the MachO/x86-64 test case.
This should fix the build failures on some of the 32-bit bots.

llvm-svn: 367767
2019-08-03 22:38:31 +00:00
Lang Hames 3daccaac8a [JITLink] Add support for MachO/x86-64 UNSIGNED relocs with length=2.
MachO/x86-64 UNSIGNED relocs are almost always 64-bit (length=3), but UNSIGNED
relocs of length=2 are allowed if the target resides in the low 32-bits. This
patch adds support for such relocations in JITLink (previously they would have
triggered an unsupported relocation error).

llvm-svn: 367764
2019-08-03 20:17:10 +00:00
Lang Hames 62a627ae78 Re-apply r364600 with fixes.
Fix: MachO/X86_64_RELOC_GOT is a 32-bit reloc, so only compare 32 bits.
llvm-svn: 364672
2019-06-28 18:36:59 +00:00
Lang Hames c29abb50f2 Revert "[JITLink][MachO/x86-64] Add a testcase for X86_64_RELOC_GOT."
Reverts commit r364600 while I investigate bot failures.

llvm-svn: 364606
2019-06-27 23:00:30 +00:00
Lang Hames 4a8dc61534 [JITLink][MachO/x86-64] Add a testcase for X86_64_RELOC_GOT.
This is the data-section counterpart to X86_64_RELOC_GOTPCREL.

llvm-svn: 364598
2019-06-27 21:50:29 +00:00
Fangrui Song ac14f7b10c [lit] Delete empty lines at the end of lit.local.cfg NFC
llvm-svn: 363538
2019-06-17 09:51:07 +00:00
Cameron McInally ce49e2231b [ExecutionEngine] Add UnaryOperator visitor to the interpreter
This is to support the unary FNeg instruction.

Differential Revision: https://reviews.llvm.org/D62881

llvm-svn: 362941
2019-06-10 14:38:48 +00:00
Lang Hames 0e124b37bd [RuntimeDyld] Apply padding and alignment bumps to all sections with stubs, and
increase the MachO/x86-64 stub alignment to 8.

Stub alignment should be guaranteed for any section containing RuntimeDyld
stubs/GOT-entries. To do this we should pad and align all sections containing
stubs, not just code sections.

This commit also bumps the MachO/x86-64 stub alignment to 8, so that GOT entries
will be aligned.

llvm-svn: 362139
2019-05-30 19:59:20 +00:00
Fangrui Song 5296e2809f Fix 2-field llvm.global_ctors `REQUIRES: asserts` tests after rL360742
llvm-svn: 360743
2019-05-15 03:08:21 +00:00
Paul Robinson ac2f5a61be Replace lit feature keyword 'not_COFF' with 'uses_COFF'.
Differential Revision: https://reviews.llvm.org/D61791

llvm-svn: 360680
2019-05-14 14:51:54 +00:00
Lang Hames 56baade10d [JITLink][MachO] Honor the no-dead-strip flag on nlist entries.
llvm-svn: 360618
2019-05-13 20:52:30 +00:00
Lang Hames 4513929094 [JITLink] Track section alignment and make sure it is respected during layout.
Previously we had only honored alignments on individual atoms, but
tools/runtimes may assume that the section alignment is respected too.

llvm-svn: 360555
2019-05-13 04:51:31 +00:00
Lang Hames 23085ec36d [JITLink] Add a test for zero-filled content.
Also updates RuntimeDyldChecker and llvm-rtdyld to support zero-fill tests by
returning a content address of zero (but no error) for zero-fill atoms, and
treating loads from zero as returning zero.

llvm-svn: 360547
2019-05-12 22:26:33 +00:00
Lang Hames b0cecfc907 [JITLink][MachO] Mark atoms in sections 'no-dead-strip' set live by default.
If a MachO section has the no-dead-strip attribute set then its atoms should
be preserved, regardless of whether they're public or referenced elsewhere in
the object.

llvm-svn: 360477
2019-05-10 22:24:37 +00:00
Lang Hames 112967833e [JITLink] Fixed a signedness bug when processing X86_64_RELOC_SUBTRACTOR.
Subtractor relocation addends are signed, so we need to read them via signed
int pointers. Accidentally treating 32-bit addends as unsigned leads to
out-of-range errors when we try to add very large (>INT32_MAX) bogus addends.

llvm-svn: 360392
2019-05-09 23:17:41 +00:00
Lang Hames 0d8ae1e343 Reapply r360194 "[JITLink] Add support for MachO .alt_entry atoms." with fixes.
This patch modifies MachOAtomGraphBuilder to use setLayoutNext rather than
addEdge, and fixes a bug in the section layout algorithm that could result in
atoms appearing more than once in the section ordering (which resulted in those
atoms being assigned invalid addresses during layout).

llvm-svn: 360205
2019-05-07 22:56:40 +00:00
Lang Hames 1a10101e21 Revert r360194 "[JITLink] Add support for MachO .alt_entry atoms."
The testcase is asserting on some bots - reverting while I investigate.

llvm-svn: 360200
2019-05-07 22:19:29 +00:00
Lang Hames 2b09b25e48 [JITLink] Add support for MachO .alt_entry atoms.
The MachO .alt_entry directive is applied to a symbol to indicate that it is
locked (in terms of address layout and liveness) to its predecessor atom. I.e.
it is an alternate entry point, at a fixed offset, for the previous atom.

This patch updates MachOAtomGraphBuilder to check for the .alt_entry flag on
symbols and add a corresponding LayoutNext edge to the atom-graph. It also
updates MachOAtomGraphBuilder_x86_64 to generalize handling of the
X86_64_RELOC_SUBTRACTOR relocation: previously either the minuend or
subtrahend of the subtraction had to be the same as the atom being fixed up,
now it is only necessary for the minuend or subtrahend to be locked (via any
chain of alt_entry directives) to the atom being fixed up.

llvm-svn: 360194
2019-05-07 21:35:14 +00:00
Lang Hames 4f349404da [JITLink] Fix some copy/paste related typos in a test case.
Several X86_64_RELOC_SUBTRACTOR tests for subtrahend handling were incorrectly
labeled as tests for kinds of minuend handling.

llvm-svn: 360160
2019-05-07 15:35:43 +00:00
Fangrui Song e29e30b139 [llvm-readobj] Change -long-option to --long-option in tests. NFC
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.

In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.

While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).

llvm-svn: 359649
2019-05-01 05:27:20 +00:00