1//===- OffloadWrapper.cpp ---------------------------------------*- C++ -*-===//
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/Frontend/Offloading/OffloadWrapper.h"
10#include "llvm/ADT/ArrayRef.h"
11#include "llvm/BinaryFormat/Magic.h"
12#include "llvm/Frontend/Offloading/Utility.h"
13#include "llvm/IR/Constants.h"
14#include "llvm/IR/GlobalVariable.h"
15#include "llvm/IR/IRBuilder.h"
16#include "llvm/IR/LLVMContext.h"
17#include "llvm/IR/Module.h"
18#include "llvm/Object/OffloadBinary.h"
19#include "llvm/Support/Error.h"
20#include "llvm/TargetParser/Triple.h"
21#include "llvm/Transforms/Utils/ModuleUtils.h"
22
23using namespace llvm;
24using namespace llvm::offloading;
25
26namespace {
27/// Magic number that begins the section containing the CUDA fatbinary.
28constexpr unsigned CudaFatMagic = 0x466243b1;
29constexpr unsigned HIPFatMagic = 0x48495046;
30
31IntegerType *getSizeTTy(Module &M) {
32 return M.getDataLayout().getIntPtrType(C&: M.getContext());
33}
34
35// struct __tgt_device_image {
36// void *ImageStart;
37// void *ImageEnd;
38// __tgt_offload_entry *EntriesBegin;
39// __tgt_offload_entry *EntriesEnd;
40// };
41StructType *getDeviceImageTy(Module &M) {
42 LLVMContext &C = M.getContext();
43 StructType *ImageTy = StructType::getTypeByName(C, Name: "__tgt_device_image");
44 if (!ImageTy)
45 ImageTy =
46 StructType::create(Name: "__tgt_device_image", elt1: PointerType::getUnqual(C),
47 elts: PointerType::getUnqual(C), elts: PointerType::getUnqual(C),
48 elts: PointerType::getUnqual(C));
49 return ImageTy;
50}
51
52PointerType *getDeviceImagePtrTy(Module &M) {
53 return PointerType::getUnqual(C&: M.getContext());
54}
55
56// struct __tgt_bin_desc {
57// int32_t NumDeviceImages;
58// __tgt_device_image *DeviceImages;
59// __tgt_offload_entry *HostEntriesBegin;
60// __tgt_offload_entry *HostEntriesEnd;
61// };
62StructType *getBinDescTy(Module &M) {
63 LLVMContext &C = M.getContext();
64 StructType *DescTy = StructType::getTypeByName(C, Name: "__tgt_bin_desc");
65 if (!DescTy)
66 DescTy = StructType::create(
67 Name: "__tgt_bin_desc", elt1: Type::getInt32Ty(C), elts: getDeviceImagePtrTy(M),
68 elts: PointerType::getUnqual(C), elts: PointerType::getUnqual(C));
69 return DescTy;
70}
71
72PointerType *getBinDescPtrTy(Module &M) {
73 return PointerType::getUnqual(C&: M.getContext());
74}
75
76/// Creates binary descriptor for the given device images. Binary descriptor
77/// is an object that is passed to the offloading runtime at program startup
78/// and it describes all device images available in the executable or shared
79/// library. It is defined as follows
80///
81/// __attribute__((visibility("hidden")))
82/// extern __tgt_offload_entry *__start_omp_offloading_entries;
83/// __attribute__((visibility("hidden")))
84/// extern __tgt_offload_entry *__stop_omp_offloading_entries;
85///
86/// static const char Image0[] = { <Bufs.front() contents> };
87/// ...
88/// static const char ImageN[] = { <Bufs.back() contents> };
89///
90/// static const __tgt_device_image Images[] = {
91/// {
92/// Image0, /*ImageStart*/
93/// Image0 + sizeof(Image0), /*ImageEnd*/
94/// __start_omp_offloading_entries, /*EntriesBegin*/
95/// __stop_omp_offloading_entries /*EntriesEnd*/
96/// },
97/// ...
98/// {
99/// ImageN, /*ImageStart*/
100/// ImageN + sizeof(ImageN), /*ImageEnd*/
101/// __start_omp_offloading_entries, /*EntriesBegin*/
102/// __stop_omp_offloading_entries /*EntriesEnd*/
103/// }
104/// };
105///
106/// static const __tgt_bin_desc BinDesc = {
107/// sizeof(Images) / sizeof(Images[0]), /*NumDeviceImages*/
108/// Images, /*DeviceImages*/
109/// __start_omp_offloading_entries, /*HostEntriesBegin*/
110/// __stop_omp_offloading_entries /*HostEntriesEnd*/
111/// };
112///
113/// Global variable that represents BinDesc is returned.
114GlobalVariable *createBinDesc(Module &M, ArrayRef<ArrayRef<char>> Bufs,
115 EntryArrayTy EntryArray, StringRef Suffix,
116 bool Relocatable) {
117 LLVMContext &C = M.getContext();
118 auto [EntriesB, EntriesE] = EntryArray;
119
120 auto *Zero = ConstantInt::get(Ty: getSizeTTy(M), V: 0u);
121 Constant *ZeroZero[] = {Zero, Zero};
122
123 // Create initializer for the images array.
124 SmallVector<Constant *, 4u> ImagesInits;
125 ImagesInits.reserve(N: Bufs.size());
126 for (ArrayRef<char> Buf : Bufs) {
127 // We embed the full offloading entry so the binary utilities can parse it.
128 auto *Data = ConstantDataArray::get(Context&: C, Elts: Buf);
129 auto *Image = new GlobalVariable(M, Data->getType(), /*isConstant=*/true,
130 GlobalVariable::InternalLinkage, Data,
131 ".omp_offloading.device_image" + Suffix);
132 Image->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
133 Image->setSection(Relocatable ? ".llvm.offloading.relocatable"
134 : ".llvm.offloading");
135 Image->setAlignment(Align(object::OffloadBinary::getAlignment()));
136
137 StringRef Binary(Buf.data(), Buf.size());
138 assert(identify_magic(Binary) == file_magic::offload_binary &&
139 "Invalid binary format");
140
141 // The device image struct contains the pointer to the beginning and end of
142 // the image stored inside of the offload binary. There should only be one
143 // of these for each buffer so we parse it out manually.
144 const auto *Header =
145 reinterpret_cast<const object::OffloadBinary::Header *>(
146 Binary.bytes_begin());
147 const auto *Entry = reinterpret_cast<const object::OffloadBinary::Entry *>(
148 Binary.bytes_begin() + Header->EntryOffset);
149
150 auto *Begin = ConstantInt::get(Ty: getSizeTTy(M), V: Entry->ImageOffset);
151 auto *Size =
152 ConstantInt::get(Ty: getSizeTTy(M), V: Entry->ImageOffset + Entry->ImageSize);
153 Constant *ZeroBegin[] = {Zero, Begin};
154 Constant *ZeroSize[] = {Zero, Size};
155
156 auto *ImageB =
157 ConstantExpr::getGetElementPtr(Ty: Image->getValueType(), C: Image, IdxList: ZeroBegin);
158 auto *ImageE =
159 ConstantExpr::getGetElementPtr(Ty: Image->getValueType(), C: Image, IdxList: ZeroSize);
160
161 ImagesInits.push_back(Elt: ConstantStruct::get(T: getDeviceImageTy(M), Vs: ImageB,
162 Vs: ImageE, Vs: EntriesB, Vs: EntriesE));
163 }
164
165 // Then create images array.
166 auto *ImagesData = ConstantArray::get(
167 T: ArrayType::get(ElementType: getDeviceImageTy(M), NumElements: ImagesInits.size()), V: ImagesInits);
168
169 auto *Images =
170 new GlobalVariable(M, ImagesData->getType(), /*isConstant*/ true,
171 GlobalValue::InternalLinkage, ImagesData,
172 ".omp_offloading.device_images" + Suffix);
173 Images->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
174
175 auto *ImagesB =
176 ConstantExpr::getGetElementPtr(Ty: Images->getValueType(), C: Images, IdxList: ZeroZero);
177
178 // And finally create the binary descriptor object.
179 auto *DescInit = ConstantStruct::get(
180 T: getBinDescTy(M),
181 Vs: ConstantInt::get(Ty: Type::getInt32Ty(C), V: ImagesInits.size()), Vs: ImagesB,
182 Vs: EntriesB, Vs: EntriesE);
183
184 return new GlobalVariable(M, DescInit->getType(), /*isConstant=*/true,
185 GlobalValue::InternalLinkage, DescInit,
186 ".omp_offloading.descriptor" + Suffix);
187}
188
189Function *createUnregisterFunction(Module &M, GlobalVariable *BinDesc,
190 StringRef Suffix) {
191 LLVMContext &C = M.getContext();
192 auto *FuncTy = FunctionType::get(Result: Type::getVoidTy(C), /*isVarArg*/ false);
193 auto *Func =
194 Function::Create(Ty: FuncTy, Linkage: GlobalValue::InternalLinkage,
195 N: ".omp_offloading.descriptor_unreg" + Suffix, M: &M);
196 Func->setSection(".text.startup");
197
198 // Get __tgt_unregister_lib function declaration.
199 auto *UnRegFuncTy = FunctionType::get(Result: Type::getVoidTy(C), Params: getBinDescPtrTy(M),
200 /*isVarArg*/ false);
201 FunctionCallee UnRegFuncC =
202 M.getOrInsertFunction(Name: "__tgt_unregister_lib", T: UnRegFuncTy);
203
204 // Construct function body
205 IRBuilder<> Builder(BasicBlock::Create(Context&: C, Name: "entry", Parent: Func));
206 Builder.CreateCall(Callee: UnRegFuncC, Args: BinDesc);
207 Builder.CreateRetVoid();
208
209 return Func;
210}
211
212void createRegisterFunction(Module &M, GlobalVariable *BinDesc,
213 StringRef Suffix) {
214 LLVMContext &C = M.getContext();
215 auto *FuncTy = FunctionType::get(Result: Type::getVoidTy(C), /*isVarArg*/ false);
216 auto *Func = Function::Create(Ty: FuncTy, Linkage: GlobalValue::InternalLinkage,
217 N: ".omp_offloading.descriptor_reg" + Suffix, M: &M);
218 Func->setSection(".text.startup");
219
220 // Get __tgt_register_lib function declaration.
221 auto *RegFuncTy = FunctionType::get(Result: Type::getVoidTy(C), Params: getBinDescPtrTy(M),
222 /*isVarArg*/ false);
223 FunctionCallee RegFuncC =
224 M.getOrInsertFunction(Name: "__tgt_register_lib", T: RegFuncTy);
225
226 auto *AtExitTy = FunctionType::get(
227 Result: Type::getInt32Ty(C), Params: PointerType::getUnqual(C), /*isVarArg=*/false);
228 FunctionCallee AtExit = M.getOrInsertFunction(Name: "atexit", T: AtExitTy);
229
230 Function *UnregFunc = createUnregisterFunction(M, BinDesc, Suffix);
231
232 // Construct function body
233 IRBuilder<> Builder(BasicBlock::Create(Context&: C, Name: "entry", Parent: Func));
234
235 Builder.CreateCall(Callee: RegFuncC, Args: BinDesc);
236
237 // Register the destructors with 'atexit'. This is expected by the CUDA
238 // runtime and ensures that we clean up before dynamic objects are destroyed.
239 // This needs to be done after plugin initialization to ensure that it is
240 // called before the plugin runtime is destroyed.
241 Builder.CreateCall(Callee: AtExit, Args: UnregFunc);
242 Builder.CreateRetVoid();
243
244 // Add this function to constructors.
245 appendToGlobalCtors(M, F: Func, /*Priority=*/101);
246}
247
248// struct fatbin_wrapper {
249// int32_t magic;
250// int32_t version;
251// void *image;
252// void *reserved;
253//};
254StructType *getFatbinWrapperTy(Module &M) {
255 LLVMContext &C = M.getContext();
256 StructType *FatbinTy = StructType::getTypeByName(C, Name: "fatbin_wrapper");
257 if (!FatbinTy)
258 FatbinTy = StructType::create(
259 Name: "fatbin_wrapper", elt1: Type::getInt32Ty(C), elts: Type::getInt32Ty(C),
260 elts: PointerType::getUnqual(C), elts: PointerType::getUnqual(C));
261 return FatbinTy;
262}
263
264/// Embed the image \p Image into the module \p M so it can be found by the
265/// runtime.
266GlobalVariable *createFatbinDesc(Module &M, ArrayRef<char> Image, bool IsHIP,
267 StringRef Suffix) {
268 LLVMContext &C = M.getContext();
269 llvm::Type *Int8PtrTy = PointerType::getUnqual(C);
270 const llvm::Triple &Triple = M.getTargetTriple();
271
272 // Create the global string containing the fatbinary.
273 StringRef FatbinConstantSection =
274 IsHIP ? ".hip_fatbin"
275 : (Triple.isMacOSX() ? "__NV_CUDA,__nv_fatbin" : ".nv_fatbin");
276 auto *Data = ConstantDataArray::get(Context&: C, Elts: Image);
277 auto *Fatbin = new GlobalVariable(M, Data->getType(), /*isConstant*/ true,
278 GlobalVariable::InternalLinkage, Data,
279 ".fatbin_image" + Suffix);
280 Fatbin->setSection(FatbinConstantSection);
281
282 // Create the fatbinary wrapper
283 StringRef FatbinWrapperSection = IsHIP ? ".hipFatBinSegment"
284 : Triple.isMacOSX() ? "__NV_CUDA,__fatbin"
285 : ".nvFatBinSegment";
286 Constant *FatbinWrapper[] = {
287 ConstantInt::get(Ty: Type::getInt32Ty(C), V: IsHIP ? HIPFatMagic : CudaFatMagic),
288 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 1),
289 ConstantExpr::getPointerBitCastOrAddrSpaceCast(C: Fatbin, Ty: Int8PtrTy),
290 ConstantPointerNull::get(T: PointerType::getUnqual(C))};
291
292 Constant *FatbinInitializer =
293 ConstantStruct::get(T: getFatbinWrapperTy(M), V: FatbinWrapper);
294
295 auto *FatbinDesc =
296 new GlobalVariable(M, getFatbinWrapperTy(M),
297 /*isConstant*/ true, GlobalValue::InternalLinkage,
298 FatbinInitializer, ".fatbin_wrapper" + Suffix);
299 FatbinDesc->setSection(FatbinWrapperSection);
300 FatbinDesc->setAlignment(Align(8));
301
302 return FatbinDesc;
303}
304
305/// Create the register globals function. We will iterate all of the offloading
306/// entries stored at the begin / end symbols and register them according to
307/// their type. This creates the following function in IR:
308///
309/// extern struct __tgt_offload_entry __start_cuda_offloading_entries;
310/// extern struct __tgt_offload_entry __stop_cuda_offloading_entries;
311///
312/// extern void __cudaRegisterFunction(void **, void *, void *, void *, int,
313/// void *, void *, void *, void *, int *);
314/// extern void __cudaRegisterVar(void **, void *, void *, void *, int32_t,
315/// int64_t, int32_t, int32_t);
316///
317/// void __cudaRegisterTest(void **fatbinHandle) {
318/// for (struct __tgt_offload_entry *entry = &__start_cuda_offloading_entries;
319/// entry != &__stop_cuda_offloading_entries; ++entry) {
320/// if (entry->Kind != OFK_CUDA)
321/// continue
322///
323/// if (!entry->Size)
324/// __cudaRegisterFunction(fatbinHandle, entry->addr, entry->name,
325/// entry->name, -1, 0, 0, 0, 0, 0);
326/// else
327/// __cudaRegisterVar(fatbinHandle, entry->addr, entry->name, entry->name,
328/// 0, entry->size, 0, 0);
329/// }
330/// }
331Function *createRegisterGlobalsFunction(Module &M, bool IsHIP,
332 EntryArrayTy EntryArray,
333 StringRef Suffix,
334 bool EmitSurfacesAndTextures) {
335 LLVMContext &C = M.getContext();
336 auto [EntriesB, EntriesE] = EntryArray;
337
338 // Get the __cudaRegisterFunction function declaration.
339 PointerType *Int8PtrTy = PointerType::get(C, AddressSpace: 0);
340 PointerType *Int8PtrPtrTy = PointerType::get(C, AddressSpace: 0);
341 PointerType *Int32PtrTy = PointerType::get(C, AddressSpace: 0);
342 auto *RegFuncTy = FunctionType::get(
343 Result: Type::getInt32Ty(C),
344 Params: {Int8PtrPtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy, Type::getInt32Ty(C),
345 Int8PtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy, Int32PtrTy},
346 /*isVarArg*/ false);
347 FunctionCallee RegFunc = M.getOrInsertFunction(
348 Name: IsHIP ? "__hipRegisterFunction" : "__cudaRegisterFunction", T: RegFuncTy);
349
350 // Get the __cudaRegisterVar function declaration.
351 auto *RegVarTy = FunctionType::get(
352 Result: Type::getVoidTy(C),
353 Params: {Int8PtrPtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy, Type::getInt32Ty(C),
354 getSizeTTy(M), Type::getInt32Ty(C), Type::getInt32Ty(C)},
355 /*isVarArg*/ false);
356 FunctionCallee RegVar = M.getOrInsertFunction(
357 Name: IsHIP ? "__hipRegisterVar" : "__cudaRegisterVar", T: RegVarTy);
358
359 // Get the __cudaRegisterSurface function declaration.
360 FunctionType *RegManagedVarTy =
361 FunctionType::get(Result: Type::getVoidTy(C),
362 Params: {Int8PtrPtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy,
363 getSizeTTy(M), Type::getInt32Ty(C)},
364 /*isVarArg=*/false);
365 FunctionCallee RegManagedVar = M.getOrInsertFunction(
366 Name: IsHIP ? "__hipRegisterManagedVar" : "__cudaRegisterManagedVar",
367 T: RegManagedVarTy);
368
369 // Get the __cudaRegisterSurface function declaration.
370 FunctionType *RegSurfaceTy =
371 FunctionType::get(Result: Type::getVoidTy(C),
372 Params: {Int8PtrPtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy,
373 Type::getInt32Ty(C), Type::getInt32Ty(C)},
374 /*isVarArg=*/false);
375 FunctionCallee RegSurface = M.getOrInsertFunction(
376 Name: IsHIP ? "__hipRegisterSurface" : "__cudaRegisterSurface", T: RegSurfaceTy);
377
378 // Get the __cudaRegisterTexture function declaration.
379 FunctionType *RegTextureTy = FunctionType::get(
380 Result: Type::getVoidTy(C),
381 Params: {Int8PtrPtrTy, Int8PtrTy, Int8PtrTy, Int8PtrTy, Type::getInt32Ty(C),
382 Type::getInt32Ty(C), Type::getInt32Ty(C)},
383 /*isVarArg=*/false);
384 FunctionCallee RegTexture = M.getOrInsertFunction(
385 Name: IsHIP ? "__hipRegisterTexture" : "__cudaRegisterTexture", T: RegTextureTy);
386
387 auto *RegGlobalsTy = FunctionType::get(Result: Type::getVoidTy(C), Params: Int8PtrPtrTy,
388 /*isVarArg*/ false);
389 auto *RegGlobalsFn =
390 Function::Create(Ty: RegGlobalsTy, Linkage: GlobalValue::InternalLinkage,
391 N: IsHIP ? ".hip.globals_reg" : ".cuda.globals_reg", M: &M);
392 RegGlobalsFn->setSection(".text.startup");
393
394 // Create the loop to register all the entries.
395 IRBuilder<> Builder(BasicBlock::Create(Context&: C, Name: "entry", Parent: RegGlobalsFn));
396 auto *EntryBB = BasicBlock::Create(Context&: C, Name: "while.entry", Parent: RegGlobalsFn);
397 auto *IfKindBB = BasicBlock::Create(Context&: C, Name: "if.kind", Parent: RegGlobalsFn);
398 auto *IfThenBB = BasicBlock::Create(Context&: C, Name: "if.then", Parent: RegGlobalsFn);
399 auto *IfElseBB = BasicBlock::Create(Context&: C, Name: "if.else", Parent: RegGlobalsFn);
400 auto *SwGlobalBB = BasicBlock::Create(Context&: C, Name: "sw.global", Parent: RegGlobalsFn);
401 auto *SwManagedBB = BasicBlock::Create(Context&: C, Name: "sw.managed", Parent: RegGlobalsFn);
402 auto *SwSurfaceBB = BasicBlock::Create(Context&: C, Name: "sw.surface", Parent: RegGlobalsFn);
403 auto *SwTextureBB = BasicBlock::Create(Context&: C, Name: "sw.texture", Parent: RegGlobalsFn);
404 auto *IfEndBB = BasicBlock::Create(Context&: C, Name: "if.end", Parent: RegGlobalsFn);
405 auto *ExitBB = BasicBlock::Create(Context&: C, Name: "while.end", Parent: RegGlobalsFn);
406
407 auto *EntryCmp = Builder.CreateICmpNE(LHS: EntriesB, RHS: EntriesE);
408 Builder.CreateCondBr(Cond: EntryCmp, True: EntryBB, False: ExitBB);
409 Builder.SetInsertPoint(EntryBB);
410 auto *Entry = Builder.CreatePHI(Ty: PointerType::getUnqual(C), NumReservedValues: 2, Name: "entry");
411 auto *AddrPtr =
412 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
413 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
414 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 4)});
415 auto *Addr = Builder.CreateLoad(Ty: Int8PtrTy, Ptr: AddrPtr, Name: "addr");
416 auto *AuxAddrPtr =
417 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
418 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
419 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 8)});
420 auto *AuxAddr = Builder.CreateLoad(Ty: Int8PtrTy, Ptr: AuxAddrPtr, Name: "aux_addr");
421 auto *KindPtr =
422 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
423 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
424 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 2)});
425 auto *Kind = Builder.CreateLoad(Ty: Type::getInt16Ty(C), Ptr: KindPtr, Name: "kind");
426 auto *NamePtr =
427 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
428 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
429 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 5)});
430 auto *Name = Builder.CreateLoad(Ty: Int8PtrTy, Ptr: NamePtr, Name: "name");
431 auto *SizePtr =
432 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
433 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
434 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 6)});
435 auto *Size = Builder.CreateLoad(Ty: Type::getInt64Ty(C), Ptr: SizePtr, Name: "size");
436 auto *FlagsPtr =
437 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
438 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
439 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 3)});
440 auto *Flags = Builder.CreateLoad(Ty: Type::getInt32Ty(C), Ptr: FlagsPtr, Name: "flags");
441 auto *DataPtr =
442 Builder.CreateInBoundsGEP(Ty: offloading::getEntryTy(M), Ptr: Entry,
443 IdxList: {ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0),
444 ConstantInt::get(Ty: Type::getInt32Ty(C), V: 7)});
445 auto *Data = Builder.CreateTrunc(
446 V: Builder.CreateLoad(Ty: Type::getInt64Ty(C), Ptr: DataPtr, Name: "data"),
447 DestTy: Type::getInt32Ty(C));
448 auto *Type = Builder.CreateAnd(
449 LHS: Flags, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0x7), Name: "type");
450
451 // Extract the flags stored in the bit-field and convert them to C booleans.
452 auto *ExternBit = Builder.CreateAnd(
453 LHS: Flags, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C),
454 V: llvm::offloading::OffloadGlobalExtern));
455 auto *Extern = Builder.CreateLShr(
456 LHS: ExternBit, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C), V: 3), Name: "extern");
457 auto *ConstantBit = Builder.CreateAnd(
458 LHS: Flags, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C),
459 V: llvm::offloading::OffloadGlobalConstant));
460 auto *Const = Builder.CreateLShr(
461 LHS: ConstantBit, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C), V: 4), Name: "constant");
462 auto *NormalizedBit = Builder.CreateAnd(
463 LHS: Flags, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C),
464 V: llvm::offloading::OffloadGlobalNormalized));
465 auto *Normalized = Builder.CreateLShr(
466 LHS: NormalizedBit, RHS: ConstantInt::get(Ty: Type::getInt32Ty(C), V: 5), Name: "normalized");
467 auto *KindCond = Builder.CreateICmpEQ(
468 LHS: Kind, RHS: ConstantInt::get(Ty: Type::getInt16Ty(C),
469 V: IsHIP ? object::OffloadKind::OFK_HIP
470 : object::OffloadKind::OFK_Cuda));
471 Builder.CreateCondBr(Cond: KindCond, True: IfKindBB, False: IfEndBB);
472 Builder.SetInsertPoint(IfKindBB);
473 auto *FnCond = Builder.CreateICmpEQ(
474 LHS: Size, RHS: ConstantInt::getNullValue(Ty: Type::getInt64Ty(C)));
475 Builder.CreateCondBr(Cond: FnCond, True: IfThenBB, False: IfElseBB);
476
477 // Create kernel registration code.
478 Builder.SetInsertPoint(IfThenBB);
479 Builder.CreateCall(Callee: RegFunc, Args: {RegGlobalsFn->arg_begin(), Addr, Name, Name,
480 ConstantInt::get(Ty: Type::getInt32Ty(C), V: -1),
481 ConstantPointerNull::get(T: Int8PtrTy),
482 ConstantPointerNull::get(T: Int8PtrTy),
483 ConstantPointerNull::get(T: Int8PtrTy),
484 ConstantPointerNull::get(T: Int8PtrTy),
485 ConstantPointerNull::get(T: Int32PtrTy)});
486 Builder.CreateBr(Dest: IfEndBB);
487 Builder.SetInsertPoint(IfElseBB);
488
489 auto *Switch = Builder.CreateSwitch(V: Type, Dest: IfEndBB);
490 // Create global variable registration code.
491 Builder.SetInsertPoint(SwGlobalBB);
492 Builder.CreateCall(Callee: RegVar,
493 Args: {RegGlobalsFn->arg_begin(), Addr, Name, Name, Extern, Size,
494 Const, ConstantInt::get(Ty: Type::getInt32Ty(C), V: 0)});
495 Builder.CreateBr(Dest: IfEndBB);
496 Switch->addCase(OnVal: Builder.getInt32(C: llvm::offloading::OffloadGlobalEntry),
497 Dest: SwGlobalBB);
498
499 // Create managed variable registration code.
500 Builder.SetInsertPoint(SwManagedBB);
501 Builder.CreateCall(Callee: RegManagedVar, Args: {RegGlobalsFn->arg_begin(), AuxAddr, Addr,
502 Name, Size, Data});
503 Builder.CreateBr(Dest: IfEndBB);
504 Switch->addCase(OnVal: Builder.getInt32(C: llvm::offloading::OffloadGlobalManagedEntry),
505 Dest: SwManagedBB);
506 // Create surface variable registration code.
507 Builder.SetInsertPoint(SwSurfaceBB);
508 if (EmitSurfacesAndTextures)
509 Builder.CreateCall(Callee: RegSurface, Args: {RegGlobalsFn->arg_begin(), Addr, Name, Name,
510 Data, Extern});
511 Builder.CreateBr(Dest: IfEndBB);
512 Switch->addCase(OnVal: Builder.getInt32(C: llvm::offloading::OffloadGlobalSurfaceEntry),
513 Dest: SwSurfaceBB);
514
515 // Create texture variable registration code.
516 Builder.SetInsertPoint(SwTextureBB);
517 if (EmitSurfacesAndTextures)
518 Builder.CreateCall(Callee: RegTexture, Args: {RegGlobalsFn->arg_begin(), Addr, Name, Name,
519 Data, Normalized, Extern});
520 Builder.CreateBr(Dest: IfEndBB);
521 Switch->addCase(OnVal: Builder.getInt32(C: llvm::offloading::OffloadGlobalTextureEntry),
522 Dest: SwTextureBB);
523
524 Builder.SetInsertPoint(IfEndBB);
525 auto *NewEntry = Builder.CreateInBoundsGEP(
526 Ty: offloading::getEntryTy(M), Ptr: Entry, IdxList: ConstantInt::get(Ty: getSizeTTy(M), V: 1));
527 auto *Cmp = Builder.CreateICmpEQ(
528 LHS: NewEntry,
529 RHS: ConstantExpr::getInBoundsGetElementPtr(
530 Ty: ArrayType::get(ElementType: offloading::getEntryTy(M), NumElements: 0), C: EntriesE,
531 IdxList: ArrayRef<Constant *>({ConstantInt::get(Ty: getSizeTTy(M), V: 0),
532 ConstantInt::get(Ty: getSizeTTy(M), V: 0)})));
533 Entry->addIncoming(
534 V: ConstantExpr::getInBoundsGetElementPtr(
535 Ty: ArrayType::get(ElementType: offloading::getEntryTy(M), NumElements: 0), C: EntriesB,
536 IdxList: ArrayRef<Constant *>({ConstantInt::get(Ty: getSizeTTy(M), V: 0),
537 ConstantInt::get(Ty: getSizeTTy(M), V: 0)})),
538 BB: &RegGlobalsFn->getEntryBlock());
539 Entry->addIncoming(V: NewEntry, BB: IfEndBB);
540 Builder.CreateCondBr(Cond: Cmp, True: ExitBB, False: EntryBB);
541 Builder.SetInsertPoint(ExitBB);
542 Builder.CreateRetVoid();
543
544 return RegGlobalsFn;
545}
546
547// Create the constructor and destructor to register the fatbinary with the CUDA
548// runtime.
549void createRegisterFatbinFunction(Module &M, GlobalVariable *FatbinDesc,
550 bool IsHIP, EntryArrayTy EntryArray,
551 StringRef Suffix,
552 bool EmitSurfacesAndTextures) {
553 LLVMContext &C = M.getContext();
554 auto *CtorFuncTy = FunctionType::get(Result: Type::getVoidTy(C), /*isVarArg*/ false);
555 auto *CtorFunc = Function::Create(
556 Ty: CtorFuncTy, Linkage: GlobalValue::InternalLinkage,
557 N: (IsHIP ? ".hip.fatbin_reg" : ".cuda.fatbin_reg") + Suffix, M: &M);
558 CtorFunc->setSection(".text.startup");
559
560 auto *DtorFuncTy = FunctionType::get(Result: Type::getVoidTy(C), /*isVarArg*/ false);
561 auto *DtorFunc = Function::Create(
562 Ty: DtorFuncTy, Linkage: GlobalValue::InternalLinkage,
563 N: (IsHIP ? ".hip.fatbin_unreg" : ".cuda.fatbin_unreg") + Suffix, M: &M);
564 DtorFunc->setSection(".text.startup");
565
566 auto *PtrTy = PointerType::getUnqual(C);
567
568 // Get the __cudaRegisterFatBinary function declaration.
569 auto *RegFatTy = FunctionType::get(Result: PtrTy, Params: PtrTy, /*isVarArg=*/false);
570 FunctionCallee RegFatbin = M.getOrInsertFunction(
571 Name: IsHIP ? "__hipRegisterFatBinary" : "__cudaRegisterFatBinary", T: RegFatTy);
572 // Get the __cudaRegisterFatBinaryEnd function declaration.
573 auto *RegFatEndTy =
574 FunctionType::get(Result: Type::getVoidTy(C), Params: PtrTy, /*isVarArg=*/false);
575 FunctionCallee RegFatbinEnd =
576 M.getOrInsertFunction(Name: "__cudaRegisterFatBinaryEnd", T: RegFatEndTy);
577 // Get the __cudaUnregisterFatBinary function declaration.
578 auto *UnregFatTy =
579 FunctionType::get(Result: Type::getVoidTy(C), Params: PtrTy, /*isVarArg=*/false);
580 FunctionCallee UnregFatbin = M.getOrInsertFunction(
581 Name: IsHIP ? "__hipUnregisterFatBinary" : "__cudaUnregisterFatBinary",
582 T: UnregFatTy);
583
584 auto *AtExitTy =
585 FunctionType::get(Result: Type::getInt32Ty(C), Params: PtrTy, /*isVarArg=*/false);
586 FunctionCallee AtExit = M.getOrInsertFunction(Name: "atexit", T: AtExitTy);
587
588 auto *BinaryHandleGlobal = new llvm::GlobalVariable(
589 M, PtrTy, false, llvm::GlobalValue::InternalLinkage,
590 llvm::ConstantPointerNull::get(T: PtrTy),
591 (IsHIP ? ".hip.binary_handle" : ".cuda.binary_handle") + Suffix);
592
593 // Create the constructor to register this image with the runtime.
594 IRBuilder<> CtorBuilder(BasicBlock::Create(Context&: C, Name: "entry", Parent: CtorFunc));
595 CallInst *Handle = CtorBuilder.CreateCall(
596 Callee: RegFatbin,
597 Args: ConstantExpr::getPointerBitCastOrAddrSpaceCast(C: FatbinDesc, Ty: PtrTy));
598 CtorBuilder.CreateAlignedStore(
599 Val: Handle, Ptr: BinaryHandleGlobal,
600 Align: Align(M.getDataLayout().getPointerTypeSize(Ty: PtrTy)));
601 CtorBuilder.CreateCall(Callee: createRegisterGlobalsFunction(M, IsHIP, EntryArray,
602 Suffix,
603 EmitSurfacesAndTextures),
604 Args: Handle);
605 if (!IsHIP)
606 CtorBuilder.CreateCall(Callee: RegFatbinEnd, Args: Handle);
607 CtorBuilder.CreateCall(Callee: AtExit, Args: DtorFunc);
608 CtorBuilder.CreateRetVoid();
609
610 // Create the destructor to unregister the image with the runtime. We cannot
611 // use a standard global destructor after CUDA 9.2 so this must be called by
612 // `atexit()` instead.
613 IRBuilder<> DtorBuilder(BasicBlock::Create(Context&: C, Name: "entry", Parent: DtorFunc));
614 LoadInst *BinaryHandle = DtorBuilder.CreateAlignedLoad(
615 Ty: PtrTy, Ptr: BinaryHandleGlobal,
616 Align: Align(M.getDataLayout().getPointerTypeSize(Ty: PtrTy)));
617 DtorBuilder.CreateCall(Callee: UnregFatbin, Args: BinaryHandle);
618 DtorBuilder.CreateRetVoid();
619
620 // Add this function to constructors.
621 appendToGlobalCtors(M, F: CtorFunc, /*Priority=*/101);
622}
623} // namespace
624
625Error offloading::wrapOpenMPBinaries(Module &M, ArrayRef<ArrayRef<char>> Images,
626 EntryArrayTy EntryArray,
627 llvm::StringRef Suffix, bool Relocatable) {
628 GlobalVariable *Desc =
629 createBinDesc(M, Bufs: Images, EntryArray, Suffix, Relocatable);
630 if (!Desc)
631 return createStringError(EC: inconvertibleErrorCode(),
632 S: "No binary descriptors created.");
633 createRegisterFunction(M, BinDesc: Desc, Suffix);
634 return Error::success();
635}
636
637Error offloading::wrapCudaBinary(Module &M, ArrayRef<char> Image,
638 EntryArrayTy EntryArray,
639 llvm::StringRef Suffix,
640 bool EmitSurfacesAndTextures) {
641 GlobalVariable *Desc = createFatbinDesc(M, Image, /*IsHip=*/IsHIP: false, Suffix);
642 if (!Desc)
643 return createStringError(EC: inconvertibleErrorCode(),
644 S: "No fatbin section created.");
645
646 createRegisterFatbinFunction(M, FatbinDesc: Desc, /*IsHip=*/IsHIP: false, EntryArray, Suffix,
647 EmitSurfacesAndTextures);
648 return Error::success();
649}
650
651Error offloading::wrapHIPBinary(Module &M, ArrayRef<char> Image,
652 EntryArrayTy EntryArray, llvm::StringRef Suffix,
653 bool EmitSurfacesAndTextures) {
654 GlobalVariable *Desc = createFatbinDesc(M, Image, /*IsHip=*/IsHIP: true, Suffix);
655 if (!Desc)
656 return createStringError(EC: inconvertibleErrorCode(),
657 S: "No fatbin section created.");
658
659 createRegisterFatbinFunction(M, FatbinDesc: Desc, /*IsHip=*/IsHIP: true, EntryArray, Suffix,
660 EmitSurfacesAndTextures);
661 return Error::success();
662}
663