1//===------- EPCIndirectionUtils.cpp -- EPC based indirection APIs --------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "llvm/ExecutionEngine/Orc/EPCIndirectionUtils.h"
10
11#include "llvm/ExecutionEngine/Orc/ExecutorProcessControl.h"
12#include "llvm/Support/MathExtras.h"
13
14#include <future>
15
16using namespace llvm;
17using namespace llvm::orc;
18
19namespace llvm {
20namespace orc {
21
22class EPCIndirectionUtilsAccess {
23public:
24 using IndirectStubInfo = EPCIndirectionUtils::IndirectStubInfo;
25 using IndirectStubInfoVector = EPCIndirectionUtils::IndirectStubInfoVector;
26
27 static Expected<IndirectStubInfoVector>
28 getIndirectStubs(EPCIndirectionUtils &EPCIU, unsigned NumStubs) {
29 return EPCIU.getIndirectStubs(NumStubs);
30 };
31};
32
33} // end namespace orc
34} // end namespace llvm
35
36namespace {
37
38class EPCTrampolinePool : public TrampolinePool {
39public:
40 EPCTrampolinePool(EPCIndirectionUtils &EPCIU);
41 Error deallocatePool();
42
43protected:
44 Error grow() override;
45
46 using FinalizedAlloc = jitlink::JITLinkMemoryManager::FinalizedAlloc;
47
48 EPCIndirectionUtils &EPCIU;
49 unsigned TrampolineSize = 0;
50 unsigned TrampolinesPerPage = 0;
51 std::vector<FinalizedAlloc> TrampolineBlocks;
52};
53
54class EPCIndirectStubsManager : public IndirectStubsManager,
55 private EPCIndirectionUtilsAccess {
56public:
57 EPCIndirectStubsManager(EPCIndirectionUtils &EPCIU) : EPCIU(EPCIU) {}
58
59 Error deallocateStubs();
60
61 Error createStub(StringRef StubName, ExecutorAddr StubAddr,
62 JITSymbolFlags StubFlags) override;
63
64 Error createStubs(const StubInitsMap &StubInits) override;
65
66 ExecutorSymbolDef findStub(StringRef Name, bool ExportedStubsOnly) override;
67
68 ExecutorSymbolDef findPointer(StringRef Name) override;
69
70 Error updatePointer(StringRef Name, ExecutorAddr NewAddr) override;
71
72private:
73 using StubInfo = std::pair<IndirectStubInfo, JITSymbolFlags>;
74
75 std::mutex ISMMutex;
76 EPCIndirectionUtils &EPCIU;
77 StringMap<StubInfo> StubInfos;
78};
79
80EPCTrampolinePool::EPCTrampolinePool(EPCIndirectionUtils &EPCIU)
81 : EPCIU(EPCIU) {
82 auto &EPC = EPCIU.getExecutorProcessControl();
83 auto &ABI = EPCIU.getABISupport();
84
85 TrampolineSize = ABI.getTrampolineSize();
86 TrampolinesPerPage =
87 (EPC.getPageSize() - ABI.getPointerSize()) / TrampolineSize;
88}
89
90Error EPCTrampolinePool::deallocatePool() {
91 std::promise<MSVCPError> DeallocResultP;
92 auto DeallocResultF = DeallocResultP.get_future();
93
94 EPCIU.getExecutorProcessControl().getMemMgr().deallocate(
95 Allocs: std::move(TrampolineBlocks),
96 OnDeallocated: [&](Error Err) { DeallocResultP.set_value(std::move(Err)); });
97
98 return DeallocResultF.get();
99}
100
101Error EPCTrampolinePool::grow() {
102 using namespace jitlink;
103
104 assert(AvailableTrampolines.empty() &&
105 "Grow called with trampolines still available");
106
107 auto ResolverAddress = EPCIU.getResolverBlockAddress();
108 assert(ResolverAddress && "Resolver address can not be null");
109
110 auto &EPC = EPCIU.getExecutorProcessControl();
111 auto PageSize = EPC.getPageSize();
112 auto Alloc = SimpleSegmentAlloc::Create(
113 MemMgr&: EPC.getMemMgr(), SSP: EPC.getSymbolStringPool(), TT: EPC.getTargetTriple(),
114 JD: nullptr, Segments: {{MemProt::Read | MemProt::Exec, {PageSize, Align(PageSize)}}});
115 if (!Alloc)
116 return Alloc.takeError();
117
118 unsigned NumTrampolines = TrampolinesPerPage;
119
120 auto SegInfo = Alloc->getSegInfo(AG: MemProt::Read | MemProt::Exec);
121 EPCIU.getABISupport().writeTrampolines(
122 TrampolineBlockWorkingMem: SegInfo.WorkingMem.data(), TrampolineBlockTragetAddr: SegInfo.Addr, ResolverAddr: ResolverAddress, NumTrampolines);
123 for (unsigned I = 0; I < NumTrampolines; ++I)
124 AvailableTrampolines.push_back(x: SegInfo.Addr + (I * TrampolineSize));
125
126 auto FA = Alloc->finalize();
127 if (!FA)
128 return FA.takeError();
129
130 TrampolineBlocks.push_back(x: std::move(*FA));
131
132 return Error::success();
133}
134
135Error EPCIndirectStubsManager::createStub(StringRef StubName,
136 ExecutorAddr StubAddr,
137 JITSymbolFlags StubFlags) {
138 StubInitsMap SIM;
139 SIM[StubName] = std::make_pair(x&: StubAddr, y&: StubFlags);
140 return createStubs(StubInits: SIM);
141}
142
143Error EPCIndirectStubsManager::createStubs(const StubInitsMap &StubInits) {
144 auto AvailableStubInfos = getIndirectStubs(EPCIU, NumStubs: StubInits.size());
145 if (!AvailableStubInfos)
146 return AvailableStubInfos.takeError();
147
148 {
149 std::lock_guard<std::mutex> Lock(ISMMutex);
150 unsigned ASIdx = 0;
151 for (auto &SI : StubInits) {
152 auto &A = (*AvailableStubInfos)[ASIdx++];
153 StubInfos[SI.first()] = std::make_pair(x&: A, y: SI.second.second);
154 }
155 }
156
157 auto &MemAccess = EPCIU.getExecutorProcessControl().getMemoryAccess();
158 switch (EPCIU.getABISupport().getPointerSize()) {
159 case 4: {
160 unsigned ASIdx = 0;
161 std::vector<tpctypes::UInt32Write> PtrUpdates;
162 for (auto &SI : StubInits)
163 PtrUpdates.push_back(x: {(*AvailableStubInfos)[ASIdx++].PointerAddress,
164 static_cast<uint32_t>(SI.second.first.getValue())});
165 return MemAccess.writeUInt32s(Ws: PtrUpdates);
166 }
167 case 8: {
168 unsigned ASIdx = 0;
169 std::vector<tpctypes::UInt64Write> PtrUpdates;
170 for (auto &SI : StubInits)
171 PtrUpdates.push_back(x: {(*AvailableStubInfos)[ASIdx++].PointerAddress,
172 static_cast<uint64_t>(SI.second.first.getValue())});
173 return MemAccess.writeUInt64s(Ws: PtrUpdates);
174 }
175 default:
176 return make_error<StringError>(Args: "Unsupported pointer size",
177 Args: inconvertibleErrorCode());
178 }
179}
180
181ExecutorSymbolDef EPCIndirectStubsManager::findStub(StringRef Name,
182 bool ExportedStubsOnly) {
183 std::lock_guard<std::mutex> Lock(ISMMutex);
184 auto I = StubInfos.find(Key: Name);
185 if (I == StubInfos.end())
186 return ExecutorSymbolDef();
187 return {I->second.first.StubAddress, I->second.second};
188}
189
190ExecutorSymbolDef EPCIndirectStubsManager::findPointer(StringRef Name) {
191 std::lock_guard<std::mutex> Lock(ISMMutex);
192 auto I = StubInfos.find(Key: Name);
193 if (I == StubInfos.end())
194 return ExecutorSymbolDef();
195 return {I->second.first.PointerAddress, I->second.second};
196}
197
198Error EPCIndirectStubsManager::updatePointer(StringRef Name,
199 ExecutorAddr NewAddr) {
200
201 ExecutorAddr PtrAddr;
202 {
203 std::lock_guard<std::mutex> Lock(ISMMutex);
204 auto I = StubInfos.find(Key: Name);
205 if (I == StubInfos.end())
206 return make_error<StringError>(Args: "Unknown stub name",
207 Args: inconvertibleErrorCode());
208 PtrAddr = I->second.first.PointerAddress;
209 }
210
211 auto &MemAccess = EPCIU.getExecutorProcessControl().getMemoryAccess();
212 switch (EPCIU.getABISupport().getPointerSize()) {
213 case 4: {
214 tpctypes::UInt32Write PUpdate(PtrAddr, NewAddr.getValue());
215 return MemAccess.writeUInt32s(Ws: PUpdate);
216 }
217 case 8: {
218 tpctypes::UInt64Write PUpdate(PtrAddr, NewAddr.getValue());
219 return MemAccess.writeUInt64s(Ws: PUpdate);
220 }
221 default:
222 return make_error<StringError>(Args: "Unsupported pointer size",
223 Args: inconvertibleErrorCode());
224 }
225}
226
227} // end anonymous namespace.
228
229namespace llvm {
230namespace orc {
231
232EPCIndirectionUtils::ABISupport::~ABISupport() = default;
233
234Expected<std::unique_ptr<EPCIndirectionUtils>>
235EPCIndirectionUtils::Create(ExecutorProcessControl &EPC) {
236 const auto &TT = EPC.getTargetTriple();
237 switch (TT.getArch()) {
238 default:
239 return make_error<StringError>(
240 Args: std::string("No EPCIndirectionUtils available for ") + TT.str(),
241 Args: inconvertibleErrorCode());
242 case Triple::aarch64:
243 case Triple::aarch64_32:
244 return CreateWithABI<OrcAArch64>(EPC);
245
246 case Triple::x86:
247 return CreateWithABI<OrcI386>(EPC);
248
249 case Triple::loongarch64:
250 return CreateWithABI<OrcLoongArch64>(EPC);
251
252 case Triple::mips:
253 return CreateWithABI<OrcMips32Be>(EPC);
254
255 case Triple::mipsel:
256 return CreateWithABI<OrcMips32Le>(EPC);
257
258 case Triple::mips64:
259 case Triple::mips64el:
260 return CreateWithABI<OrcMips64>(EPC);
261
262 case Triple::riscv64:
263 return CreateWithABI<OrcRiscv64>(EPC);
264
265 case Triple::x86_64:
266 if (TT.getOS() == Triple::OSType::Win32)
267 return CreateWithABI<OrcX86_64_Win32>(EPC);
268 else
269 return CreateWithABI<OrcX86_64_SysV>(EPC);
270 }
271}
272
273Error EPCIndirectionUtils::cleanup() {
274
275 auto &MemMgr = EPC.getMemMgr();
276 auto Err = MemMgr.deallocate(Allocs: std::move(IndirectStubAllocs));
277
278 if (TP)
279 Err = joinErrors(E1: std::move(Err),
280 E2: static_cast<EPCTrampolinePool &>(*TP).deallocatePool());
281
282 if (ResolverBlock)
283 Err =
284 joinErrors(E1: std::move(Err), E2: MemMgr.deallocate(Alloc: std::move(ResolverBlock)));
285
286 return Err;
287}
288
289Expected<ExecutorAddr>
290EPCIndirectionUtils::writeResolverBlock(ExecutorAddr ReentryFnAddr,
291 ExecutorAddr ReentryCtxAddr) {
292 using namespace jitlink;
293
294 assert(ABI && "ABI can not be null");
295 auto ResolverSize = ABI->getResolverCodeSize();
296
297 auto Alloc =
298 SimpleSegmentAlloc::Create(MemMgr&: EPC.getMemMgr(), SSP: EPC.getSymbolStringPool(),
299 TT: EPC.getTargetTriple(), JD: nullptr,
300 Segments: {{MemProt::Read | MemProt::Exec,
301 {ResolverSize, Align(EPC.getPageSize())}}});
302
303 if (!Alloc)
304 return Alloc.takeError();
305
306 auto SegInfo = Alloc->getSegInfo(AG: MemProt::Read | MemProt::Exec);
307 ResolverBlockAddr = SegInfo.Addr;
308 ABI->writeResolverCode(ResolverWorkingMem: SegInfo.WorkingMem.data(), ResolverTargetAddr: ResolverBlockAddr,
309 ReentryFnAddr, ReentryCtxAddr);
310
311 auto FA = Alloc->finalize();
312 if (!FA)
313 return FA.takeError();
314
315 ResolverBlock = std::move(*FA);
316 return ResolverBlockAddr;
317}
318
319std::unique_ptr<IndirectStubsManager>
320EPCIndirectionUtils::createIndirectStubsManager() {
321 return std::make_unique<EPCIndirectStubsManager>(args&: *this);
322}
323
324TrampolinePool &EPCIndirectionUtils::getTrampolinePool() {
325 if (!TP)
326 TP = std::make_unique<EPCTrampolinePool>(args&: *this);
327 return *TP;
328}
329
330LazyCallThroughManager &EPCIndirectionUtils::createLazyCallThroughManager(
331 ExecutionSession &ES, ExecutorAddr ErrorHandlerAddr) {
332 assert(!LCTM &&
333 "createLazyCallThroughManager can not have been called before");
334 LCTM = std::make_unique<LazyCallThroughManager>(args&: ES, args&: ErrorHandlerAddr,
335 args: &getTrampolinePool());
336 return *LCTM;
337}
338
339EPCIndirectionUtils::EPCIndirectionUtils(ExecutorProcessControl &EPC,
340 std::unique_ptr<ABISupport> ABI)
341 : EPC(EPC), ABI(std::move(ABI)) {
342 assert(this->ABI && "ABI can not be null");
343
344 assert(EPC.getPageSize() > getABISupport().getStubSize() &&
345 "Stubs larger than one page are not supported");
346}
347
348Expected<EPCIndirectionUtils::IndirectStubInfoVector>
349EPCIndirectionUtils::getIndirectStubs(unsigned NumStubs) {
350 using namespace jitlink;
351
352 std::lock_guard<std::mutex> Lock(EPCUIMutex);
353
354 // If there aren't enough stubs available then allocate some more.
355 if (NumStubs > AvailableIndirectStubs.size()) {
356 auto NumStubsToAllocate = NumStubs;
357 auto PageSize = EPC.getPageSize();
358 auto StubBytes = alignTo(Value: NumStubsToAllocate * ABI->getStubSize(), Align: PageSize);
359 NumStubsToAllocate = StubBytes / ABI->getStubSize();
360 auto PtrBytes =
361 alignTo(Value: NumStubsToAllocate * ABI->getPointerSize(), Align: PageSize);
362
363 auto StubProt = MemProt::Read | MemProt::Exec;
364 auto PtrProt = MemProt::Read | MemProt::Write;
365
366 auto Alloc = SimpleSegmentAlloc::Create(
367 MemMgr&: EPC.getMemMgr(), SSP: EPC.getSymbolStringPool(), TT: EPC.getTargetTriple(),
368 JD: nullptr,
369 Segments: {{StubProt, {static_cast<size_t>(StubBytes), Align(PageSize)}},
370 {PtrProt, {static_cast<size_t>(PtrBytes), Align(PageSize)}}});
371
372 if (!Alloc)
373 return Alloc.takeError();
374
375 auto StubSeg = Alloc->getSegInfo(AG: StubProt);
376 auto PtrSeg = Alloc->getSegInfo(AG: PtrProt);
377
378 ABI->writeIndirectStubsBlock(StubsBlockWorkingMem: StubSeg.WorkingMem.data(), StubsBlockTargetAddress: StubSeg.Addr,
379 PointersBlockTargetAddress: PtrSeg.Addr, NumStubs: NumStubsToAllocate);
380
381 auto FA = Alloc->finalize();
382 if (!FA)
383 return FA.takeError();
384
385 IndirectStubAllocs.push_back(x: std::move(*FA));
386
387 auto StubExecutorAddr = StubSeg.Addr;
388 auto PtrExecutorAddr = PtrSeg.Addr;
389 for (unsigned I = 0; I != NumStubsToAllocate; ++I) {
390 AvailableIndirectStubs.push_back(
391 x: IndirectStubInfo(StubExecutorAddr, PtrExecutorAddr));
392 StubExecutorAddr += ABI->getStubSize();
393 PtrExecutorAddr += ABI->getPointerSize();
394 }
395 }
396
397 assert(NumStubs <= AvailableIndirectStubs.size() &&
398 "Sufficient stubs should have been allocated above");
399
400 IndirectStubInfoVector Result;
401 while (NumStubs--) {
402 Result.push_back(x: AvailableIndirectStubs.back());
403 AvailableIndirectStubs.pop_back();
404 }
405
406 return std::move(Result);
407}
408
409static JITTargetAddress reentry(JITTargetAddress LCTMAddr,
410 JITTargetAddress TrampolineAddr) {
411 auto &LCTM = *jitTargetAddressToPointer<LazyCallThroughManager *>(Addr: LCTMAddr);
412 std::promise<ExecutorAddr> LandingAddrP;
413 auto LandingAddrF = LandingAddrP.get_future();
414 LCTM.resolveTrampolineLandingAddress(
415 TrampolineAddr: ExecutorAddr(TrampolineAddr),
416 NotifyLandingResolved: [&](ExecutorAddr Addr) { LandingAddrP.set_value(Addr); });
417 return LandingAddrF.get().getValue();
418}
419
420Error setUpInProcessLCTMReentryViaEPCIU(EPCIndirectionUtils &EPCIU) {
421 auto &LCTM = EPCIU.getLazyCallThroughManager();
422 return EPCIU
423 .writeResolverBlock(ReentryFnAddr: ExecutorAddr::fromPtr(Ptr: &reentry),
424 ReentryCtxAddr: ExecutorAddr::fromPtr(Ptr: &LCTM))
425 .takeError();
426}
427
428} // end namespace orc
429} // end namespace llvm
430