Commit Graph

420 Commits

Author SHA1 Message Date
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
Lang Hames a9fdf375b3 [ORC] Add a 'plugin' interface to ObjectLinkingLayer for events/configuration.
ObjectLinkingLayer::Plugin provides event notifications when objects are loaded,
emitted, and removed. It also provides a modifyPassConfig callback that allows
plugins to modify the JITLink pass configuration.

This patch moves eh-frame registration into its own plugin, and teaches
llvm-jitlink to only add that plugin when performing execution runs on
non-Windows platforms. This should allow us to re-enable the test case that was
removed in r359198.

llvm-svn: 359357
2019-04-26 22:58:39 +00:00
Lang Hames b534f7245c Revert "[JITLink] Make the JITLink MachO/x86-64 eh-frame test work on Windows."
This reverts r359169, as it broke one of the windows bots.

llvm-svn: 359198
2019-04-25 15:18:31 +00:00
Lang Hames 64eb9a95be [JITLink] Make the JITLink MachO/x86-64 eh-frame test work on Windows.
This should fix the MachO/x86-64 eh-frame regression test by ensuring that
the symbols __ZTIi and ___gxx_personality_v0 are defined on all platforms.

llvm-svn: 359169
2019-04-25 05:24:40 +00:00
Reid Kleckner 54763e4453 Mark new jitlink test XFAIL for windows
llvm-svn: 359151
2019-04-24 23:11:17 +00:00
Lang Hames b1ba4d8a8a [JITLink] Refer to FDE's CIE (not the most recent CIE) when parsing eh-frame.
Frame Descriptor Entries (FDEs) have a pointer back to a Common Information
Entry (CIE) that describes how the rest FDE should be parsed. JITLink had been
assuming that FDEs always referred to the most recent CIE encountered, but the
spec allows them to point back to any previously encountered CIE. This patch
fixes JITLink to look up the correct CIE for the FDE.

The testcase is a MachO binary with an FDE that refers to a CIE that is not the
one immediately proceeding it (the layout can be viewed wit
'dwarfdump --eh-frame <testcase>'. This test case had to be a binary as llvm-mc
now sorts FDEs (as of r356216) to ensure FDEs *do* point to the most recent CIE.

llvm-svn: 359105
2019-04-24 15:15:55 +00:00
Lang Hames 3474ba4f22 [JITLink] Disable MachO/x86-64 regression test if the X86 target is not built.
llvm-svn: 358830
2019-04-20 21:32:49 +00:00
Lang Hames 11c8dfa583 Initial implementation of JITLink - A replacement for RuntimeDyld.
Summary:

JITLink is a jit-linker that performs the same high-level task as RuntimeDyld:
it parses relocatable object files and makes their contents runnable in a target
process.

JITLink aims to improve on RuntimeDyld in several ways:

(1) A clear design intended to maximize code-sharing while minimizing coupling.

RuntimeDyld has been developed in an ad-hoc fashion for a number of years and
this had led to intermingling of code for multiple architectures (e.g. in
RuntimeDyldELF::processRelocationRef) in a way that makes the code more
difficult to read, reason about, extend. JITLink is designed to isolate
format and architecture specific code, while still sharing generic code.

(2) Support for native code models.

RuntimeDyld required the use of large code models (where calls to external
functions are made indirectly via registers) for many of platforms due to its
restrictive model for stub generation (one "stub" per symbol). JITLink allows
arbitrary mutation of the atom graph, allowing both GOT and PLT atoms to be
added naturally.

(3) Native support for asynchronous linking.

JITLink uses asynchronous calls for symbol resolution and finalization: these
callbacks are passed a continuation function that they must call to complete the
linker's work. This allows for cleaner interoperation with the new concurrent
ORC JIT APIs, while still being easily implementable in synchronous style if
asynchrony is not needed.

To maximise sharing, the design has a hierarchy of common code:

(1) Generic atom-graph data structure and algorithms (e.g. dead stripping and
 |  memory allocation) that are intended to be shared by all architectures.
 |
 + -- (2) Shared per-format code that utilizes (1), e.g. Generic MachO to
       |  atom-graph parsing.
       |
       + -- (3) Architecture specific code that uses (1) and (2). E.g.
                JITLinkerMachO_x86_64, which adds x86-64 specific relocation
                support to (2) to build and patch up the atom graph.

To support asynchronous symbol resolution and finalization, the callbacks for
these operations take continuations as arguments:

  using JITLinkAsyncLookupContinuation =
      std::function<void(Expected<AsyncLookupResult> LR)>;

  using JITLinkAsyncLookupFunction =
      std::function<void(const DenseSet<StringRef> &Symbols,
                         JITLinkAsyncLookupContinuation LookupContinuation)>;

  using FinalizeContinuation = std::function<void(Error)>;

  virtual void finalizeAsync(FinalizeContinuation OnFinalize);

In addition to its headline features, JITLink also makes other improvements:

  - Dead stripping support: symbols that are not used (e.g. redundant ODR
    definitions) are discarded, and take up no memory in the target process
    (In contrast, RuntimeDyld supported pointer equality for weak definitions,
    but the redundant definitions stayed resident in memory).

  - Improved exception handling support. JITLink provides a much more extensive
    eh-frame parser than RuntimeDyld, and is able to correctly fix up many
    eh-frame sections that RuntimeDyld currently (silently) fails on.

  - More extensive validation and error handling throughout.

This initial patch supports linking MachO/x86-64 only. Work on support for
other architectures and formats will happen in-tree.

Differential Revision: https://reviews.llvm.org/D58704

llvm-svn: 358818
2019-04-20 17:10:34 +00:00
Lang Hames c7c1f21525 Simplify decoupling between RuntimeDyld/RuntimeDyldChecker, add 'got_addr' util.
This patch reduces the number of functions in the interface between RuntimeDyld
and RuntimeDyldChecker by combining "GetXAddress" and "GetXContent" functions
into "GetXInfo" functions that return a struct describing both the address and
content. The GetStubOffset function is also replaced with a pair of utilities,
GetStubInfo and GetGOTInfo, that fit the new scheme. For RuntimeDyld both of
these functions will return the same result, but for the new JITLink linker
(https://reviews.llvm.org/D58704) these will provide the addresses of PLT stubs
and GOT entries respectively.

For JITLink's use, a 'got_addr' utility has been added to the rtdyld-check
language, and the syntax of 'got_addr' and 'stub_addr' has been changed: both
functions now take two arguments, a 'stub container name' and a target symbol
name. For llvm-rtdyld/RuntimeDyld the stub container name is the object file
name and section name, separated by a slash. E.g.:

rtdyld-check: *{8}(stub_addr(foo.o/__text, y)) = y

For the upcoming llvm-jitlink utility, which creates stubs on a per-file basis
rather than a per-section basis, the container name is just the file name. E.g.:

jitlink-check: *{8}(got_addr(foo.o, y)) = y
llvm-svn: 358295
2019-04-12 18:07:28 +00:00
James Henderson 9bc817a0ae [yaml2obj]Allow explicit symbol indexes in relocations and emit error for bad names
Prior to this change, the "Symbol" field of a relocation would always be
assumed to be a symbol name, and if no such symbol existed, the
relocation would reference index 0. This confused me when I tried to use
a literal symbol index in the field: since "0x1" was not a known symbol
name, the symbol index was set as 0. This change falls back to treating
unknown symbol names as integers, and emits an error if the name is not
found and the string is not an integer.

Note that the Symbol field is optional, so if a relocation doesn't
reference a symbol, it shouldn't be specified. The new error required a
number of test updates.

Reviewed by: grimar, ruiu
Differential Revision: https://reviews.llvm.org/D58510

llvm-svn: 355938
2019-03-12 17:00:25 +00:00
Nathan Lanza 893083ae5e Implement IMAGE_REL_AMD64_SECREL for RuntimeDyldCOFFX86_64
lldb on Windows uses the ExecutionEngine for expression evaluation
and hits the llvm_unreachable due to this relocation. Thus, implement
the relocation and add a test to verify it's function.

llvm-svn: 348904
2018-12-12 00:04:06 +00:00
Lang Hames a4d5b34f73 [ExecutionEngine][Interpreter] Fix out-of-bounds array access.
If args is empty then accesing element 0 is illegal.

https://reviews.llvm.org/D53556

Patch by Eugene Sharygin. Thanks Eugene!

llvm-svn: 347281
2018-11-20 01:01:26 +00:00
Lang Hames 23cb2e7f77 [ORC] Re-apply r345077 with fixes to remove ambiguity in lookup calls.
llvm-svn: 345098
2018-10-23 23:01:39 +00:00
Reid Kleckner db367e952e Revert r345077 "[ORC] Change how non-exported symbols are matched during lookup."
Doesn't build on Windows. The call to 'lookup' is ambiguous. Clang and
MSVC agree, anyway.

http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/787
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\unittests\ExecutionEngine\Orc\CoreAPIsTest.cpp(315): error C2668: 'llvm::orc::ExecutionSession::lookup': ambiguous call to overloaded function
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\include\llvm/ExecutionEngine/Orc/Core.h(823): note: could be 'llvm::Expected<llvm::JITEvaluatedSymbol> llvm::orc::ExecutionSession::lookup(llvm::ArrayRef<llvm::orc::JITDylib *>,llvm::orc::SymbolStringPtr)'
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\include\llvm/ExecutionEngine/Orc/Core.h(817): note: or       'llvm::Expected<llvm::JITEvaluatedSymbol> llvm::orc::ExecutionSession::lookup(const llvm::orc::JITDylibSearchList &,llvm::orc::SymbolStringPtr)'
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\unittests\ExecutionEngine\Orc\CoreAPIsTest.cpp(315): note: while trying to match the argument list '(initializer list, llvm::orc::SymbolStringPtr)'

llvm-svn: 345078
2018-10-23 20:54:43 +00:00
Lang Hames 841796decd [ORC] Change how non-exported symbols are matched during lookup.
In the new scheme the client passes a list of (JITDylib&, bool) pairs, rather
than a list of JITDylibs. For each JITDylib the boolean indicates whether or not
to match against non-exported symbols (true means that they should be found,
false means that they should not). The MatchNonExportedInJD and MatchNonExported
parameters on lookup are removed.

The new scheme is more flexible, and easier to understand.

This patch also updates JITDylib search orders to be lists of (JITDylib&, bool)
pairs to match the new lookup scheme. Error handling is also plumbed through
the LLJIT class to allow regression tests to fail predictably when a lookup from
a lazy call-through fails.

llvm-svn: 345077
2018-10-23 20:20:22 +00:00
Lang Hames 776f1d50c8 [RuntimeDyld][COFF] Skip non-loaded sections when calculating ImageBase.
Non-loaded sections (whose unused load-address defaults to zero) should not
be taken into account when calculating ImageBase, or ImageBase will be
incorrectly set to 0.

Patch by Andrew Scheidecker. Thanks Andrew!

https://reviews.llvm.org/D51343

+        // The Sections list may contain sections that weren't loaded for
+        // whatever reason: they may be debug sections, and ProcessAllSections
+        // is false, or they may be sections that contain 0 bytes. If the
+        // section isn't loaded, the load address will be 0, and it should not
+        // be included in the ImageBase calculation.

llvm-svn: 344995
2018-10-23 01:36:33 +00:00
Lang Hames e433cf1fd7 [ORC] Add some more basic sanity tests for the LLJIT.
minimal.ll contains a main function that returns zero, and
single-function-call.ll contains a main function that calls a foo function that
returns zero. These minimal tests can help to rule out some trivial JIT bugs
when other tests fail.

This commit also renames hello.ll to global-ctors-and-dtors.ll, which better
reflects what it is actually testing.

llvm-svn: 344863
2018-10-20 20:39:53 +00:00
Lang Hames 98440293fb [ORC] Add partitioning support to CompileOnDemandLayer2.
CompileOnDemandLayer2 now supports user-supplied partition functions (the
original CompileOnDemandLayer already supported these).

Partition functions are called with the list of requested global values
(i.e. global values that currently have queries waiting on them) and have an
opportunity to select extra global values to materialize at the same time.

Also adds testing infrastructure for the new feature to lli.

llvm-svn: 343396
2018-09-29 23:49:57 +00:00
Lang Hames f0a3fd885d Reapply r343058 with a fix for -DLLVM_ENABLE_THREADS=OFF.
Modifies lit to add a 'thread_support' feature that can be used in lit test
REQUIRES clauses. The thread_support flag is set if -DLLVM_ENABLE_THREADS=ON
and unset if -DLLVM_ENABLE_THREADS=OFF. The lit flag is used to disable the
multiple-compile-threads-basic.ll testcase when threading is disabled.

llvm-svn: 343122
2018-09-26 16:26:59 +00:00
Hans Wennborg 20b5abe23b Revert r343058 "[ORC] Add support for multithreaded compiles to LLJIT and LLLazyJIT."
This doesn't work well in builds configured with LLVM_ENABLE_THREADS=OFF,
causing the following assert when running
ExecutionEngine/OrcLazy/multiple-compile-threads-basic.ll:

  lib/ExecutionEngine/Orc/Core.cpp:1748: Expected<llvm::JITEvaluatedSymbol>
  llvm::orc::lookup(const llvm::orc::JITDylibList &, llvm::orc::SymbolStringPtr):
  Assertion `ResultMap->size() == 1 && "Unexpected number of results"' failed.

> LLJIT and LLLazyJIT can now be constructed with an optional NumCompileThreads
> arguments. If this is non-zero then a thread-pool will be created with the
> given number of threads, and compile tasks will be dispatched to the thread
> pool.
>
> To enable testing of this feature, two new flags are added to lli:
>
> (1) -compile-threads=N (N = 0 by default) controls the number of compile threads
> to use.
>
> (2) -thread-entry can be used to execute code on additional threads. For each
> -thread-entry argument supplied (multiple are allowed) a new thread will be
> created and the given symbol called. These additional thread entry points are
> called after static constructors are run, but before main.

llvm-svn: 343099
2018-09-26 12:15:23 +00:00
Lang Hames d8048675f4 [ORC] Update CompileOnDemandLayer2 to use the new lazyReexports mechanism
for lazy compilation, rather than a callback manager.

The new mechanism does not block compile threads, and does not require
function bodies to be renamed.

Future modifications should allow laziness on a per-module basis to work
without any modification of the input module.

llvm-svn: 343065
2018-09-26 05:08:29 +00:00
Lang Hames 225a32af72 [ORC] Add support for multithreaded compiles to LLJIT and LLLazyJIT.
LLJIT and LLLazyJIT can now be constructed with an optional NumCompileThreads
arguments. If this is non-zero then a thread-pool will be created with the
given number of threads, and compile tasks will be dispatched to the thread
pool.

To enable testing of this feature, two new flags are added to lli:

(1) -compile-threads=N (N = 0 by default) controls the number of compile threads
to use.

(2) -thread-entry can be used to execute code on additional threads. For each
-thread-entry argument supplied (multiple are allowed) a new thread will be
created and the given symbol called. These additional thread entry points are
called after static constructors are run, but before main.

llvm-svn: 343058
2018-09-26 02:39:42 +00:00
Petar Jovanovic 5abf4bb552 [MIPS] ORC JIT support
This patch adds support for ORC JIT for mips/mips64 architecture.
In common code $static is changed to __ORCstatic because on MIPS
architecture "$" is a reserved character.

Patch by Luka Ercegovcevic

Differential Revision: https://reviews.llvm.org/D49665

llvm-svn: 341934
2018-09-11 13:10:04 +00:00
Lang Hames 5f711c794d [ORC] Add a testcase for r338975.
Tests that bad object files generate a predictable error from the JIT APIs.

llvm-svn: 340881
2018-08-28 22:50:59 +00:00
Lang Hames 6cadc7c06b [ORC] Replace lookupFlags in JITSymbolResolver with getResponsibilitySet.
The new method name/behavior more closely models the way it was being used.
It also fixes an assertion that can occur when using the new ORC Core APIs,
where flags alone don't necessarily provide enough context to decide whether
the caller is responsible for materializing a given symbol (which was always
the reason this API existed).

The default implementation of getResponsibilitySet uses lookupFlags to determine
responsibility as before, so existing JITSymbolResolvers should continue to
work.

llvm-svn: 340874
2018-08-28 21:18:05 +00:00
Lang Hames 37a66413c1 [ORC] Add an addObjectFile method to LLJIT.
The addObjectFile method adds the given object file to the JIT session, making
its code available for execution.

Support for the -extra-object flag is added to lli when operating in
-jit-kind=orc-lazy mode to support testing of this feature.

llvm-svn: 340870
2018-08-28 20:20:31 +00:00
Lang Hames 35c4702773 [RuntimeDyld] Add test case that was accidentally left out of r340125.
llvm-svn: 340788
2018-08-27 22:48:01 +00:00
Petr Hosek eb46c95c3e [CMake] Use normalized Windows target triples
Changes the default Windows target triple returned by
GetHostTriple.cmake from the old environment names (which we wanted to
move away from) to newer, normalized ones. This also requires updating
all tests to use the new systems names in constraints.

Differential Revision: https://reviews.llvm.org/D47381

llvm-svn: 339307
2018-08-09 02:16:18 +00:00
Reid Kleckner 980c4df037 Re-land r335297 "[X86] Implement more of x86-64 large and medium PIC code models"
Don't try to generate large PIC code for non-ELF targets. Neither COFF
nor MachO have relocations for large position independent code, and
users have been using "large PIC" code models to JIT 64-bit code for a
while now. With this change, if they are generating ELF code, their
JITed code will truly be PIC, but if they target MachO or COFF, it will
contain 64-bit immediates that directly reference external symbols. For
a JIT, that's perfectly fine.

llvm-svn: 337740
2018-07-23 21:14:35 +00:00
Jonas Devlieghere b757fc3878 Revert "Re-land r335297 "[X86] Implement more of x86-64 large and medium PIC code models""
Reverting because this is causing failures in the LLDB test suite on
GreenDragon.

  LLVM ERROR: unsupported relocation with subtraction expression, symbol
  '__GLOBAL_OFFSET_TABLE_' can not be undefined in a subtraction
  expression

llvm-svn: 335894
2018-06-28 17:56:43 +00:00