Lang Hames eae6d6d18b Re-reapply "[ORC] Enable JIT support for the compact-unwind..." with fixes.
Re-enables compact-unwind support in JITLink, which was reverted in b04847b427d
due to buildbot failures.

The underlying cause for the failures on the buildbots was the lack of
compact-unwind registration support on older Darwin OSes. Since the
CompactUnwindManager pass now removes eh-frames by default we were left with
unwind-info that could not be registered. On x86-64, where eh-frame info is
produced by default the solution is to fall back to using eh-frames. On arm64
we simply can't support exceptions on older OSes.

This patch updates the EHFrameRegistrationPlugin to remove the compact-unwind
section (__LD,__compact_unwind) when installed, forcing use of eh-frames when
the EHFrameRegistrationPlugin is used. In LLJIT, the EHFrameRegistrationPlugin
continues to be used for all non-Darwin platform, and will be added on Darwin
platforms when the a CompactUnwindRegistrationPlugin instance can't be created
(e.g. due to missing support for compact-unwind info registration).

The lit.cfg.py script is updated to check whether the host OSes default unwind
info supports JIT registration, allowing tests to be disabled for older Darwin
OSes on arm64.
2025-02-05 19:40:30 +11:00

97 lines
2.9 KiB
C++

//===------ CompileUtils.cpp - Utilities for compiling IR in the JIT ------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/ExecutionEngine/Orc/CompileUtils.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ExecutionEngine/ObjectCache.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/SmallVectorMemoryBuffer.h"
#include "llvm/Target/TargetMachine.h"
namespace llvm {
namespace orc {
IRSymbolMapper::ManglingOptions
irManglingOptionsFromTargetOptions(const TargetOptions &Opts) {
IRSymbolMapper::ManglingOptions MO;
MO.EmulatedTLS = Opts.EmulatedTLS;
return MO;
}
/// Compile a Module to an ObjectFile.
Expected<SimpleCompiler::CompileResult> SimpleCompiler::operator()(Module &M) {
if (M.getDataLayout().isDefault())
M.setDataLayout(TM.createDataLayout());
CompileResult CachedObject = tryToLoadFromObjectCache(M);
if (CachedObject)
return std::move(CachedObject);
SmallVector<char, 0> ObjBufferSV;
{
raw_svector_ostream ObjStream(ObjBufferSV);
legacy::PassManager PM;
MCContext *Ctx;
if (TM.addPassesToEmitMC(PM, Ctx, ObjStream))
return make_error<StringError>("Target does not support MC emission",
inconvertibleErrorCode());
PM.run(M);
}
auto ObjBuffer = std::make_unique<SmallVectorMemoryBuffer>(
std::move(ObjBufferSV), M.getModuleIdentifier() + "-jitted-objectbuffer",
/*RequiresNullTerminator=*/false);
auto Obj = object::ObjectFile::createObjectFile(ObjBuffer->getMemBufferRef());
if (!Obj)
return Obj.takeError();
notifyObjectCompiled(M, *ObjBuffer);
return std::move(ObjBuffer);
}
SimpleCompiler::CompileResult
SimpleCompiler::tryToLoadFromObjectCache(const Module &M) {
if (!ObjCache)
return CompileResult();
return ObjCache->getObject(&M);
}
void SimpleCompiler::notifyObjectCompiled(const Module &M,
const MemoryBuffer &ObjBuffer) {
if (ObjCache)
ObjCache->notifyObjectCompiled(&M, ObjBuffer.getMemBufferRef());
}
ConcurrentIRCompiler::ConcurrentIRCompiler(JITTargetMachineBuilder JTMB,
ObjectCache *ObjCache)
: IRCompiler(irManglingOptionsFromTargetOptions(JTMB.getOptions())),
JTMB(std::move(JTMB)), ObjCache(ObjCache) {}
Expected<std::unique_ptr<MemoryBuffer>>
ConcurrentIRCompiler::operator()(Module &M) {
auto TM = cantFail(JTMB.createTargetMachine());
SimpleCompiler C(*TM, ObjCache);
return C(M);
}
} // end namespace orc
} // end namespace llvm