1 //===-- AMDGPUTargetStreamer.cpp - Mips Target Streamer Methods -----------===//
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 // This file provides AMDGPU specific target streamer methods.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "AMDGPUTargetStreamer.h"
14 #include "AMDGPUPTNote.h"
15 #include "AMDKernelCodeT.h"
16 #include "Utils/AMDGPUBaseInfo.h"
17 #include "Utils/AMDKernelCodeTUtils.h"
18 #include "llvm/BinaryFormat/AMDGPUMetadataVerifier.h"
19 #include "llvm/BinaryFormat/ELF.h"
20 #include "llvm/MC/MCAssembler.h"
21 #include "llvm/MC/MCContext.h"
22 #include "llvm/MC/MCELFStreamer.h"
23 #include "llvm/MC/MCSectionELF.h"
24 #include "llvm/MC/MCSubtargetInfo.h"
25 #include "llvm/Support/AMDGPUMetadata.h"
26 #include "llvm/Support/AMDHSAKernelDescriptor.h"
27 #include "llvm/Support/Casting.h"
28 #include "llvm/Support/FormattedStream.h"
29 #include "llvm/Support/TargetParser.h"
30 
31 using namespace llvm;
32 using namespace llvm::AMDGPU;
33 
34 //===----------------------------------------------------------------------===//
35 // AMDGPUTargetStreamer
36 //===----------------------------------------------------------------------===//
37 
38 static void convertIsaVersionV2(uint32_t &Major, uint32_t &Minor,
39                                 uint32_t &Stepping, bool Sramecc, bool Xnack) {
40   if (Major == 9 && Minor == 0) {
41     switch (Stepping) {
42       case 0:
43       case 2:
44       case 4:
45       case 6:
46         if (Xnack)
47           Stepping++;
48     }
49   }
50 }
51 
52 bool AMDGPUTargetStreamer::EmitHSAMetadataV2(StringRef HSAMetadataString) {
53   HSAMD::Metadata HSAMetadata;
54   if (HSAMD::fromString(HSAMetadataString, HSAMetadata))
55     return false;
56   return EmitHSAMetadata(HSAMetadata);
57 }
58 
59 bool AMDGPUTargetStreamer::EmitHSAMetadataV3(StringRef HSAMetadataString) {
60   msgpack::Document HSAMetadataDoc;
61   if (!HSAMetadataDoc.fromYAML(HSAMetadataString))
62     return false;
63   return EmitHSAMetadata(HSAMetadataDoc, false);
64 }
65 
66 StringRef AMDGPUTargetStreamer::getArchNameFromElfMach(unsigned ElfMach) {
67   AMDGPU::GPUKind AK;
68 
69   switch (ElfMach) {
70   default: llvm_unreachable("Unhandled ELF::EF_AMDGPU type");
71   case ELF::EF_AMDGPU_MACH_R600_R600:      AK = GK_R600;    break;
72   case ELF::EF_AMDGPU_MACH_R600_R630:      AK = GK_R630;    break;
73   case ELF::EF_AMDGPU_MACH_R600_RS880:     AK = GK_RS880;   break;
74   case ELF::EF_AMDGPU_MACH_R600_RV670:     AK = GK_RV670;   break;
75   case ELF::EF_AMDGPU_MACH_R600_RV710:     AK = GK_RV710;   break;
76   case ELF::EF_AMDGPU_MACH_R600_RV730:     AK = GK_RV730;   break;
77   case ELF::EF_AMDGPU_MACH_R600_RV770:     AK = GK_RV770;   break;
78   case ELF::EF_AMDGPU_MACH_R600_CEDAR:     AK = GK_CEDAR;   break;
79   case ELF::EF_AMDGPU_MACH_R600_CYPRESS:   AK = GK_CYPRESS; break;
80   case ELF::EF_AMDGPU_MACH_R600_JUNIPER:   AK = GK_JUNIPER; break;
81   case ELF::EF_AMDGPU_MACH_R600_REDWOOD:   AK = GK_REDWOOD; break;
82   case ELF::EF_AMDGPU_MACH_R600_SUMO:      AK = GK_SUMO;    break;
83   case ELF::EF_AMDGPU_MACH_R600_BARTS:     AK = GK_BARTS;   break;
84   case ELF::EF_AMDGPU_MACH_R600_CAICOS:    AK = GK_CAICOS;  break;
85   case ELF::EF_AMDGPU_MACH_R600_CAYMAN:    AK = GK_CAYMAN;  break;
86   case ELF::EF_AMDGPU_MACH_R600_TURKS:     AK = GK_TURKS;   break;
87   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX600:  AK = GK_GFX600;  break;
88   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX601:  AK = GK_GFX601;  break;
89   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX602:  AK = GK_GFX602;  break;
90   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX700:  AK = GK_GFX700;  break;
91   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX701:  AK = GK_GFX701;  break;
92   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX702:  AK = GK_GFX702;  break;
93   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX703:  AK = GK_GFX703;  break;
94   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX704:  AK = GK_GFX704;  break;
95   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX705:  AK = GK_GFX705;  break;
96   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX801:  AK = GK_GFX801;  break;
97   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX802:  AK = GK_GFX802;  break;
98   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX803:  AK = GK_GFX803;  break;
99   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX805:  AK = GK_GFX805;  break;
100   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX810:  AK = GK_GFX810;  break;
101   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX900:  AK = GK_GFX900;  break;
102   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX902:  AK = GK_GFX902;  break;
103   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX904:  AK = GK_GFX904;  break;
104   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX906:  AK = GK_GFX906;  break;
105   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX908:  AK = GK_GFX908;  break;
106   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX909:  AK = GK_GFX909;  break;
107   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX90A:  AK = GK_GFX90A;  break;
108   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX90C:  AK = GK_GFX90C;  break;
109   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX940:  AK = GK_GFX940;  break;
110   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1010: AK = GK_GFX1010; break;
111   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1011: AK = GK_GFX1011; break;
112   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1012: AK = GK_GFX1012; break;
113   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1013: AK = GK_GFX1013; break;
114   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1030: AK = GK_GFX1030; break;
115   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1031: AK = GK_GFX1031; break;
116   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1032: AK = GK_GFX1032; break;
117   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1033: AK = GK_GFX1033; break;
118   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1034: AK = GK_GFX1034; break;
119   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1035: AK = GK_GFX1035; break;
120   case ELF::EF_AMDGPU_MACH_AMDGCN_GFX1036: AK = GK_GFX1036; break;
121   case ELF::EF_AMDGPU_MACH_NONE:           AK = GK_NONE;    break;
122   }
123 
124   StringRef GPUName = getArchNameAMDGCN(AK);
125   if (GPUName != "")
126     return GPUName;
127   return getArchNameR600(AK);
128 }
129 
130 unsigned AMDGPUTargetStreamer::getElfMach(StringRef GPU) {
131   AMDGPU::GPUKind AK = parseArchAMDGCN(GPU);
132   if (AK == AMDGPU::GPUKind::GK_NONE)
133     AK = parseArchR600(GPU);
134 
135   switch (AK) {
136   case GK_R600:    return ELF::EF_AMDGPU_MACH_R600_R600;
137   case GK_R630:    return ELF::EF_AMDGPU_MACH_R600_R630;
138   case GK_RS880:   return ELF::EF_AMDGPU_MACH_R600_RS880;
139   case GK_RV670:   return ELF::EF_AMDGPU_MACH_R600_RV670;
140   case GK_RV710:   return ELF::EF_AMDGPU_MACH_R600_RV710;
141   case GK_RV730:   return ELF::EF_AMDGPU_MACH_R600_RV730;
142   case GK_RV770:   return ELF::EF_AMDGPU_MACH_R600_RV770;
143   case GK_CEDAR:   return ELF::EF_AMDGPU_MACH_R600_CEDAR;
144   case GK_CYPRESS: return ELF::EF_AMDGPU_MACH_R600_CYPRESS;
145   case GK_JUNIPER: return ELF::EF_AMDGPU_MACH_R600_JUNIPER;
146   case GK_REDWOOD: return ELF::EF_AMDGPU_MACH_R600_REDWOOD;
147   case GK_SUMO:    return ELF::EF_AMDGPU_MACH_R600_SUMO;
148   case GK_BARTS:   return ELF::EF_AMDGPU_MACH_R600_BARTS;
149   case GK_CAICOS:  return ELF::EF_AMDGPU_MACH_R600_CAICOS;
150   case GK_CAYMAN:  return ELF::EF_AMDGPU_MACH_R600_CAYMAN;
151   case GK_TURKS:   return ELF::EF_AMDGPU_MACH_R600_TURKS;
152   case GK_GFX600:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX600;
153   case GK_GFX601:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX601;
154   case GK_GFX602:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX602;
155   case GK_GFX700:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX700;
156   case GK_GFX701:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX701;
157   case GK_GFX702:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX702;
158   case GK_GFX703:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX703;
159   case GK_GFX704:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX704;
160   case GK_GFX705:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX705;
161   case GK_GFX801:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX801;
162   case GK_GFX802:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX802;
163   case GK_GFX803:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX803;
164   case GK_GFX805:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX805;
165   case GK_GFX810:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX810;
166   case GK_GFX900:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX900;
167   case GK_GFX902:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX902;
168   case GK_GFX904:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX904;
169   case GK_GFX906:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX906;
170   case GK_GFX908:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX908;
171   case GK_GFX909:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX909;
172   case GK_GFX90A:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX90A;
173   case GK_GFX90C:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX90C;
174   case GK_GFX940:  return ELF::EF_AMDGPU_MACH_AMDGCN_GFX940;
175   case GK_GFX1010: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1010;
176   case GK_GFX1011: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1011;
177   case GK_GFX1012: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1012;
178   case GK_GFX1013: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1013;
179   case GK_GFX1030: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1030;
180   case GK_GFX1031: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1031;
181   case GK_GFX1032: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1032;
182   case GK_GFX1033: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1033;
183   case GK_GFX1034: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1034;
184   case GK_GFX1035: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1035;
185   case GK_GFX1036: return ELF::EF_AMDGPU_MACH_AMDGCN_GFX1036;
186   case GK_NONE:    return ELF::EF_AMDGPU_MACH_NONE;
187   }
188 
189   llvm_unreachable("unknown GPU");
190 }
191 
192 //===----------------------------------------------------------------------===//
193 // AMDGPUTargetAsmStreamer
194 //===----------------------------------------------------------------------===//
195 
196 AMDGPUTargetAsmStreamer::AMDGPUTargetAsmStreamer(MCStreamer &S,
197                                                  formatted_raw_ostream &OS)
198     : AMDGPUTargetStreamer(S), OS(OS) { }
199 
200 // A hook for emitting stuff at the end.
201 // We use it for emitting the accumulated PAL metadata as directives.
202 // The PAL metadata is reset after it is emitted.
203 void AMDGPUTargetAsmStreamer::finish() {
204   std::string S;
205   getPALMetadata()->toString(S);
206   OS << S;
207 
208   // Reset the pal metadata so its data will not affect a compilation that
209   // reuses this object.
210   getPALMetadata()->reset();
211 }
212 
213 void AMDGPUTargetAsmStreamer::EmitDirectiveAMDGCNTarget() {
214   OS << "\t.amdgcn_target \"" << getTargetID()->toString() << "\"\n";
215 }
216 
217 void AMDGPUTargetAsmStreamer::EmitDirectiveHSACodeObjectVersion(
218     uint32_t Major, uint32_t Minor) {
219   OS << "\t.hsa_code_object_version " <<
220         Twine(Major) << "," << Twine(Minor) << '\n';
221 }
222 
223 void
224 AMDGPUTargetAsmStreamer::EmitDirectiveHSACodeObjectISAV2(uint32_t Major,
225                                                          uint32_t Minor,
226                                                          uint32_t Stepping,
227                                                          StringRef VendorName,
228                                                          StringRef ArchName) {
229   convertIsaVersionV2(Major, Minor, Stepping, TargetID->isSramEccOnOrAny(), TargetID->isXnackOnOrAny());
230   OS << "\t.hsa_code_object_isa " << Twine(Major) << "," << Twine(Minor) << ","
231      << Twine(Stepping) << ",\"" << VendorName << "\",\"" << ArchName << "\"\n";
232 }
233 
234 void
235 AMDGPUTargetAsmStreamer::EmitAMDKernelCodeT(const amd_kernel_code_t &Header) {
236   OS << "\t.amd_kernel_code_t\n";
237   dumpAmdKernelCode(&Header, OS, "\t\t");
238   OS << "\t.end_amd_kernel_code_t\n";
239 }
240 
241 void AMDGPUTargetAsmStreamer::EmitAMDGPUSymbolType(StringRef SymbolName,
242                                                    unsigned Type) {
243   switch (Type) {
244     default: llvm_unreachable("Invalid AMDGPU symbol type");
245     case ELF::STT_AMDGPU_HSA_KERNEL:
246       OS << "\t.amdgpu_hsa_kernel " << SymbolName << '\n' ;
247       break;
248   }
249 }
250 
251 void AMDGPUTargetAsmStreamer::emitAMDGPULDS(MCSymbol *Symbol, unsigned Size,
252                                             Align Alignment) {
253   OS << "\t.amdgpu_lds " << Symbol->getName() << ", " << Size << ", "
254      << Alignment.value() << '\n';
255 }
256 
257 bool AMDGPUTargetAsmStreamer::EmitISAVersion() {
258   OS << "\t.amd_amdgpu_isa \"" << getTargetID()->toString() << "\"\n";
259   return true;
260 }
261 
262 bool AMDGPUTargetAsmStreamer::EmitHSAMetadata(
263     const AMDGPU::HSAMD::Metadata &HSAMetadata) {
264   std::string HSAMetadataString;
265   if (HSAMD::toString(HSAMetadata, HSAMetadataString))
266     return false;
267 
268   OS << '\t' << HSAMD::AssemblerDirectiveBegin << '\n';
269   OS << HSAMetadataString << '\n';
270   OS << '\t' << HSAMD::AssemblerDirectiveEnd << '\n';
271   return true;
272 }
273 
274 bool AMDGPUTargetAsmStreamer::EmitHSAMetadata(
275     msgpack::Document &HSAMetadataDoc, bool Strict) {
276   HSAMD::V3::MetadataVerifier Verifier(Strict);
277   if (!Verifier.verify(HSAMetadataDoc.getRoot()))
278     return false;
279 
280   std::string HSAMetadataString;
281   raw_string_ostream StrOS(HSAMetadataString);
282   HSAMetadataDoc.toYAML(StrOS);
283 
284   OS << '\t' << HSAMD::V3::AssemblerDirectiveBegin << '\n';
285   OS << StrOS.str() << '\n';
286   OS << '\t' << HSAMD::V3::AssemblerDirectiveEnd << '\n';
287   return true;
288 }
289 
290 bool AMDGPUTargetAsmStreamer::EmitCodeEnd(const MCSubtargetInfo &STI) {
291   const uint32_t Encoded_s_code_end = 0xbf9f0000;
292   const uint32_t Encoded_s_nop = 0xbf800000;
293   uint32_t Encoded_pad = Encoded_s_code_end;
294 
295   // Instruction cache line size in bytes.
296   const unsigned Log2CacheLineSize = 6;
297   const unsigned CacheLineSize = 1u << Log2CacheLineSize;
298 
299   // Extra padding amount in bytes to support prefetch mode 3.
300   unsigned FillSize = 3 * CacheLineSize;
301 
302   if (AMDGPU::isGFX90A(STI)) {
303     Encoded_pad = Encoded_s_nop;
304     FillSize = 16 * CacheLineSize;
305   }
306 
307   OS << "\t.p2alignl " << Log2CacheLineSize << ", " << Encoded_pad << '\n';
308   OS << "\t.fill " << (FillSize / 4) << ", 4, " << Encoded_pad << '\n';
309   return true;
310 }
311 
312 void AMDGPUTargetAsmStreamer::EmitAmdhsaKernelDescriptor(
313     const MCSubtargetInfo &STI, StringRef KernelName,
314     const amdhsa::kernel_descriptor_t &KD, uint64_t NextVGPR, uint64_t NextSGPR,
315     bool ReserveVCC, bool ReserveFlatScr) {
316   IsaVersion IVersion = getIsaVersion(STI.getCPU());
317 
318   OS << "\t.amdhsa_kernel " << KernelName << '\n';
319 
320 #define PRINT_FIELD(STREAM, DIRECTIVE, KERNEL_DESC, MEMBER_NAME, FIELD_NAME)   \
321   STREAM << "\t\t" << DIRECTIVE << " "                                         \
322          << AMDHSA_BITS_GET(KERNEL_DESC.MEMBER_NAME, FIELD_NAME) << '\n';
323 
324   OS << "\t\t.amdhsa_group_segment_fixed_size " << KD.group_segment_fixed_size
325      << '\n';
326   OS << "\t\t.amdhsa_private_segment_fixed_size "
327      << KD.private_segment_fixed_size << '\n';
328   OS << "\t\t.amdhsa_kernarg_size " << KD.kernarg_size << '\n';
329 
330   PRINT_FIELD(OS, ".amdhsa_user_sgpr_count", KD,
331               compute_pgm_rsrc2,
332               amdhsa::COMPUTE_PGM_RSRC2_USER_SGPR_COUNT);
333 
334   if (!hasArchitectedFlatScratch(STI))
335     PRINT_FIELD(
336         OS, ".amdhsa_user_sgpr_private_segment_buffer", KD,
337         kernel_code_properties,
338         amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_PRIVATE_SEGMENT_BUFFER);
339   PRINT_FIELD(OS, ".amdhsa_user_sgpr_dispatch_ptr", KD,
340               kernel_code_properties,
341               amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_DISPATCH_PTR);
342   PRINT_FIELD(OS, ".amdhsa_user_sgpr_queue_ptr", KD,
343               kernel_code_properties,
344               amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_QUEUE_PTR);
345   PRINT_FIELD(OS, ".amdhsa_user_sgpr_kernarg_segment_ptr", KD,
346               kernel_code_properties,
347               amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_KERNARG_SEGMENT_PTR);
348   PRINT_FIELD(OS, ".amdhsa_user_sgpr_dispatch_id", KD,
349               kernel_code_properties,
350               amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_DISPATCH_ID);
351   if (!hasArchitectedFlatScratch(STI))
352     PRINT_FIELD(OS, ".amdhsa_user_sgpr_flat_scratch_init", KD,
353                 kernel_code_properties,
354                 amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_FLAT_SCRATCH_INIT);
355   PRINT_FIELD(OS, ".amdhsa_user_sgpr_private_segment_size", KD,
356               kernel_code_properties,
357               amdhsa::KERNEL_CODE_PROPERTY_ENABLE_SGPR_PRIVATE_SEGMENT_SIZE);
358   if (IVersion.Major >= 10)
359     PRINT_FIELD(OS, ".amdhsa_wavefront_size32", KD,
360                 kernel_code_properties,
361                 amdhsa::KERNEL_CODE_PROPERTY_ENABLE_WAVEFRONT_SIZE32);
362   PRINT_FIELD(OS,
363               (hasArchitectedFlatScratch(STI)
364                    ? ".amdhsa_enable_private_segment"
365                    : ".amdhsa_system_sgpr_private_segment_wavefront_offset"),
366               KD, compute_pgm_rsrc2,
367               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_PRIVATE_SEGMENT);
368   PRINT_FIELD(OS, ".amdhsa_system_sgpr_workgroup_id_x", KD,
369               compute_pgm_rsrc2,
370               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_SGPR_WORKGROUP_ID_X);
371   PRINT_FIELD(OS, ".amdhsa_system_sgpr_workgroup_id_y", KD,
372               compute_pgm_rsrc2,
373               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_SGPR_WORKGROUP_ID_Y);
374   PRINT_FIELD(OS, ".amdhsa_system_sgpr_workgroup_id_z", KD,
375               compute_pgm_rsrc2,
376               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_SGPR_WORKGROUP_ID_Z);
377   PRINT_FIELD(OS, ".amdhsa_system_sgpr_workgroup_info", KD,
378               compute_pgm_rsrc2,
379               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_SGPR_WORKGROUP_INFO);
380   PRINT_FIELD(OS, ".amdhsa_system_vgpr_workitem_id", KD,
381               compute_pgm_rsrc2,
382               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_VGPR_WORKITEM_ID);
383 
384   // These directives are required.
385   OS << "\t\t.amdhsa_next_free_vgpr " << NextVGPR << '\n';
386   OS << "\t\t.amdhsa_next_free_sgpr " << NextSGPR << '\n';
387 
388   if (AMDGPU::isGFX90A(STI))
389     OS << "\t\t.amdhsa_accum_offset " <<
390       (AMDHSA_BITS_GET(KD.compute_pgm_rsrc3,
391                        amdhsa::COMPUTE_PGM_RSRC3_GFX90A_ACCUM_OFFSET) + 1) * 4
392       << '\n';
393 
394   if (!ReserveVCC)
395     OS << "\t\t.amdhsa_reserve_vcc " << ReserveVCC << '\n';
396   if (IVersion.Major >= 7 && !ReserveFlatScr && !hasArchitectedFlatScratch(STI))
397     OS << "\t\t.amdhsa_reserve_flat_scratch " << ReserveFlatScr << '\n';
398 
399   if (Optional<uint8_t> HsaAbiVer = getHsaAbiVersion(&STI)) {
400     switch (*HsaAbiVer) {
401     default:
402       break;
403     case ELF::ELFABIVERSION_AMDGPU_HSA_V2:
404       break;
405     case ELF::ELFABIVERSION_AMDGPU_HSA_V3:
406     case ELF::ELFABIVERSION_AMDGPU_HSA_V4:
407     case ELF::ELFABIVERSION_AMDGPU_HSA_V5:
408       if (getTargetID()->isXnackSupported())
409         OS << "\t\t.amdhsa_reserve_xnack_mask " << getTargetID()->isXnackOnOrAny() << '\n';
410       break;
411     }
412   }
413 
414   PRINT_FIELD(OS, ".amdhsa_float_round_mode_32", KD,
415               compute_pgm_rsrc1,
416               amdhsa::COMPUTE_PGM_RSRC1_FLOAT_ROUND_MODE_32);
417   PRINT_FIELD(OS, ".amdhsa_float_round_mode_16_64", KD,
418               compute_pgm_rsrc1,
419               amdhsa::COMPUTE_PGM_RSRC1_FLOAT_ROUND_MODE_16_64);
420   PRINT_FIELD(OS, ".amdhsa_float_denorm_mode_32", KD,
421               compute_pgm_rsrc1,
422               amdhsa::COMPUTE_PGM_RSRC1_FLOAT_DENORM_MODE_32);
423   PRINT_FIELD(OS, ".amdhsa_float_denorm_mode_16_64", KD,
424               compute_pgm_rsrc1,
425               amdhsa::COMPUTE_PGM_RSRC1_FLOAT_DENORM_MODE_16_64);
426   PRINT_FIELD(OS, ".amdhsa_dx10_clamp", KD,
427               compute_pgm_rsrc1,
428               amdhsa::COMPUTE_PGM_RSRC1_ENABLE_DX10_CLAMP);
429   PRINT_FIELD(OS, ".amdhsa_ieee_mode", KD,
430               compute_pgm_rsrc1,
431               amdhsa::COMPUTE_PGM_RSRC1_ENABLE_IEEE_MODE);
432   if (IVersion.Major >= 9)
433     PRINT_FIELD(OS, ".amdhsa_fp16_overflow", KD,
434                 compute_pgm_rsrc1,
435                 amdhsa::COMPUTE_PGM_RSRC1_FP16_OVFL);
436   if (AMDGPU::isGFX90A(STI))
437     PRINT_FIELD(OS, ".amdhsa_tg_split", KD,
438                 compute_pgm_rsrc3,
439                 amdhsa::COMPUTE_PGM_RSRC3_GFX90A_TG_SPLIT);
440   if (IVersion.Major >= 10) {
441     PRINT_FIELD(OS, ".amdhsa_workgroup_processor_mode", KD,
442                 compute_pgm_rsrc1,
443                 amdhsa::COMPUTE_PGM_RSRC1_WGP_MODE);
444     PRINT_FIELD(OS, ".amdhsa_memory_ordered", KD,
445                 compute_pgm_rsrc1,
446                 amdhsa::COMPUTE_PGM_RSRC1_MEM_ORDERED);
447     PRINT_FIELD(OS, ".amdhsa_forward_progress", KD,
448                 compute_pgm_rsrc1,
449                 amdhsa::COMPUTE_PGM_RSRC1_FWD_PROGRESS);
450     PRINT_FIELD(OS, ".amdhsa_shared_vgpr_count", KD, compute_pgm_rsrc3,
451                 amdhsa::COMPUTE_PGM_RSRC3_GFX10_SHARED_VGPR_COUNT);
452   }
453   PRINT_FIELD(
454       OS, ".amdhsa_exception_fp_ieee_invalid_op", KD,
455       compute_pgm_rsrc2,
456       amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_IEEE_754_FP_INVALID_OPERATION);
457   PRINT_FIELD(OS, ".amdhsa_exception_fp_denorm_src", KD,
458               compute_pgm_rsrc2,
459               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_FP_DENORMAL_SOURCE);
460   PRINT_FIELD(
461       OS, ".amdhsa_exception_fp_ieee_div_zero", KD,
462       compute_pgm_rsrc2,
463       amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_IEEE_754_FP_DIVISION_BY_ZERO);
464   PRINT_FIELD(OS, ".amdhsa_exception_fp_ieee_overflow", KD,
465               compute_pgm_rsrc2,
466               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_IEEE_754_FP_OVERFLOW);
467   PRINT_FIELD(OS, ".amdhsa_exception_fp_ieee_underflow", KD,
468               compute_pgm_rsrc2,
469               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_IEEE_754_FP_UNDERFLOW);
470   PRINT_FIELD(OS, ".amdhsa_exception_fp_ieee_inexact", KD,
471               compute_pgm_rsrc2,
472               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_IEEE_754_FP_INEXACT);
473   PRINT_FIELD(OS, ".amdhsa_exception_int_div_zero", KD,
474               compute_pgm_rsrc2,
475               amdhsa::COMPUTE_PGM_RSRC2_ENABLE_EXCEPTION_INT_DIVIDE_BY_ZERO);
476 #undef PRINT_FIELD
477 
478   OS << "\t.end_amdhsa_kernel\n";
479 }
480 
481 //===----------------------------------------------------------------------===//
482 // AMDGPUTargetELFStreamer
483 //===----------------------------------------------------------------------===//
484 
485 AMDGPUTargetELFStreamer::AMDGPUTargetELFStreamer(MCStreamer &S,
486                                                  const MCSubtargetInfo &STI)
487     : AMDGPUTargetStreamer(S), STI(STI), Streamer(S) {}
488 
489 MCELFStreamer &AMDGPUTargetELFStreamer::getStreamer() {
490   return static_cast<MCELFStreamer &>(Streamer);
491 }
492 
493 // A hook for emitting stuff at the end.
494 // We use it for emitting the accumulated PAL metadata as a .note record.
495 // The PAL metadata is reset after it is emitted.
496 void AMDGPUTargetELFStreamer::finish() {
497   MCAssembler &MCA = getStreamer().getAssembler();
498   MCA.setELFHeaderEFlags(getEFlags());
499 
500   std::string Blob;
501   const char *Vendor = getPALMetadata()->getVendor();
502   unsigned Type = getPALMetadata()->getType();
503   getPALMetadata()->toBlob(Type, Blob);
504   if (Blob.empty())
505     return;
506   EmitNote(Vendor, MCConstantExpr::create(Blob.size(), getContext()), Type,
507            [&](MCELFStreamer &OS) { OS.emitBytes(Blob); });
508 
509   // Reset the pal metadata so its data will not affect a compilation that
510   // reuses this object.
511   getPALMetadata()->reset();
512 }
513 
514 void AMDGPUTargetELFStreamer::EmitNote(
515     StringRef Name, const MCExpr *DescSZ, unsigned NoteType,
516     function_ref<void(MCELFStreamer &)> EmitDesc) {
517   auto &S = getStreamer();
518   auto &Context = S.getContext();
519 
520   auto NameSZ = Name.size() + 1;
521 
522   unsigned NoteFlags = 0;
523   // TODO Apparently, this is currently needed for OpenCL as mentioned in
524   // https://reviews.llvm.org/D74995
525   if (STI.getTargetTriple().getOS() == Triple::AMDHSA)
526     NoteFlags = ELF::SHF_ALLOC;
527 
528   S.PushSection();
529   S.SwitchSection(
530       Context.getELFSection(ElfNote::SectionName, ELF::SHT_NOTE, NoteFlags));
531   S.emitInt32(NameSZ);                                        // namesz
532   S.emitValue(DescSZ, 4);                                     // descz
533   S.emitInt32(NoteType);                                      // type
534   S.emitBytes(Name);                                          // name
535   S.emitValueToAlignment(4, 0, 1, 0);                         // padding 0
536   EmitDesc(S);                                                // desc
537   S.emitValueToAlignment(4, 0, 1, 0);                         // padding 0
538   S.PopSection();
539 }
540 
541 unsigned AMDGPUTargetELFStreamer::getEFlags() {
542   switch (STI.getTargetTriple().getArch()) {
543   default:
544     llvm_unreachable("Unsupported Arch");
545   case Triple::r600:
546     return getEFlagsR600();
547   case Triple::amdgcn:
548     return getEFlagsAMDGCN();
549   }
550 }
551 
552 unsigned AMDGPUTargetELFStreamer::getEFlagsR600() {
553   assert(STI.getTargetTriple().getArch() == Triple::r600);
554 
555   return getElfMach(STI.getCPU());
556 }
557 
558 unsigned AMDGPUTargetELFStreamer::getEFlagsAMDGCN() {
559   assert(STI.getTargetTriple().getArch() == Triple::amdgcn);
560 
561   switch (STI.getTargetTriple().getOS()) {
562   default:
563     // TODO: Why are some tests have "mingw" listed as OS?
564     // llvm_unreachable("Unsupported OS");
565   case Triple::UnknownOS:
566     return getEFlagsUnknownOS();
567   case Triple::AMDHSA:
568     return getEFlagsAMDHSA();
569   case Triple::AMDPAL:
570     return getEFlagsAMDPAL();
571   case Triple::Mesa3D:
572     return getEFlagsMesa3D();
573   }
574 }
575 
576 unsigned AMDGPUTargetELFStreamer::getEFlagsUnknownOS() {
577   // TODO: Why are some tests have "mingw" listed as OS?
578   // assert(STI.getTargetTriple().getOS() == Triple::UnknownOS);
579 
580   return getEFlagsV3();
581 }
582 
583 unsigned AMDGPUTargetELFStreamer::getEFlagsAMDHSA() {
584   assert(STI.getTargetTriple().getOS() == Triple::AMDHSA);
585 
586   if (Optional<uint8_t> HsaAbiVer = getHsaAbiVersion(&STI)) {
587     switch (*HsaAbiVer) {
588     case ELF::ELFABIVERSION_AMDGPU_HSA_V2:
589     case ELF::ELFABIVERSION_AMDGPU_HSA_V3:
590       return getEFlagsV3();
591     case ELF::ELFABIVERSION_AMDGPU_HSA_V4:
592     case ELF::ELFABIVERSION_AMDGPU_HSA_V5:
593       return getEFlagsV4();
594     }
595   }
596 
597   llvm_unreachable("HSA OS ABI Version identification must be defined");
598 }
599 
600 unsigned AMDGPUTargetELFStreamer::getEFlagsAMDPAL() {
601   assert(STI.getTargetTriple().getOS() == Triple::AMDPAL);
602 
603   return getEFlagsV3();
604 }
605 
606 unsigned AMDGPUTargetELFStreamer::getEFlagsMesa3D() {
607   assert(STI.getTargetTriple().getOS() == Triple::Mesa3D);
608 
609   return getEFlagsV3();
610 }
611 
612 unsigned AMDGPUTargetELFStreamer::getEFlagsV3() {
613   unsigned EFlagsV3 = 0;
614 
615   // mach.
616   EFlagsV3 |= getElfMach(STI.getCPU());
617 
618   // xnack.
619   if (getTargetID()->isXnackOnOrAny())
620     EFlagsV3 |= ELF::EF_AMDGPU_FEATURE_XNACK_V3;
621   // sramecc.
622   if (getTargetID()->isSramEccOnOrAny())
623     EFlagsV3 |= ELF::EF_AMDGPU_FEATURE_SRAMECC_V3;
624 
625   return EFlagsV3;
626 }
627 
628 unsigned AMDGPUTargetELFStreamer::getEFlagsV4() {
629   unsigned EFlagsV4 = 0;
630 
631   // mach.
632   EFlagsV4 |= getElfMach(STI.getCPU());
633 
634   // xnack.
635   switch (getTargetID()->getXnackSetting()) {
636   case AMDGPU::IsaInfo::TargetIDSetting::Unsupported:
637     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_XNACK_UNSUPPORTED_V4;
638     break;
639   case AMDGPU::IsaInfo::TargetIDSetting::Any:
640     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_XNACK_ANY_V4;
641     break;
642   case AMDGPU::IsaInfo::TargetIDSetting::Off:
643     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_XNACK_OFF_V4;
644     break;
645   case AMDGPU::IsaInfo::TargetIDSetting::On:
646     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_XNACK_ON_V4;
647     break;
648   }
649   // sramecc.
650   switch (getTargetID()->getSramEccSetting()) {
651   case AMDGPU::IsaInfo::TargetIDSetting::Unsupported:
652     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_SRAMECC_UNSUPPORTED_V4;
653     break;
654   case AMDGPU::IsaInfo::TargetIDSetting::Any:
655     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_SRAMECC_ANY_V4;
656     break;
657   case AMDGPU::IsaInfo::TargetIDSetting::Off:
658     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_SRAMECC_OFF_V4;
659     break;
660   case AMDGPU::IsaInfo::TargetIDSetting::On:
661     EFlagsV4 |= ELF::EF_AMDGPU_FEATURE_SRAMECC_ON_V4;
662     break;
663   }
664 
665   return EFlagsV4;
666 }
667 
668 void AMDGPUTargetELFStreamer::EmitDirectiveAMDGCNTarget() {}
669 
670 void AMDGPUTargetELFStreamer::EmitDirectiveHSACodeObjectVersion(
671     uint32_t Major, uint32_t Minor) {
672 
673   EmitNote(ElfNote::NoteNameV2, MCConstantExpr::create(8, getContext()),
674            ELF::NT_AMD_HSA_CODE_OBJECT_VERSION, [&](MCELFStreamer &OS) {
675              OS.emitInt32(Major);
676              OS.emitInt32(Minor);
677            });
678 }
679 
680 void
681 AMDGPUTargetELFStreamer::EmitDirectiveHSACodeObjectISAV2(uint32_t Major,
682                                                          uint32_t Minor,
683                                                          uint32_t Stepping,
684                                                          StringRef VendorName,
685                                                          StringRef ArchName) {
686   uint16_t VendorNameSize = VendorName.size() + 1;
687   uint16_t ArchNameSize = ArchName.size() + 1;
688 
689   unsigned DescSZ = sizeof(VendorNameSize) + sizeof(ArchNameSize) +
690     sizeof(Major) + sizeof(Minor) + sizeof(Stepping) +
691     VendorNameSize + ArchNameSize;
692 
693   convertIsaVersionV2(Major, Minor, Stepping, TargetID->isSramEccOnOrAny(), TargetID->isXnackOnOrAny());
694   EmitNote(ElfNote::NoteNameV2, MCConstantExpr::create(DescSZ, getContext()),
695            ELF::NT_AMD_HSA_ISA_VERSION, [&](MCELFStreamer &OS) {
696              OS.emitInt16(VendorNameSize);
697              OS.emitInt16(ArchNameSize);
698              OS.emitInt32(Major);
699              OS.emitInt32(Minor);
700              OS.emitInt32(Stepping);
701              OS.emitBytes(VendorName);
702              OS.emitInt8(0); // NULL terminate VendorName
703              OS.emitBytes(ArchName);
704              OS.emitInt8(0); // NULL terminate ArchName
705            });
706 }
707 
708 void
709 AMDGPUTargetELFStreamer::EmitAMDKernelCodeT(const amd_kernel_code_t &Header) {
710 
711   MCStreamer &OS = getStreamer();
712   OS.PushSection();
713   OS.emitBytes(StringRef((const char*)&Header, sizeof(Header)));
714   OS.PopSection();
715 }
716 
717 void AMDGPUTargetELFStreamer::EmitAMDGPUSymbolType(StringRef SymbolName,
718                                                    unsigned Type) {
719   MCSymbolELF *Symbol = cast<MCSymbolELF>(
720       getStreamer().getContext().getOrCreateSymbol(SymbolName));
721   Symbol->setType(Type);
722 }
723 
724 void AMDGPUTargetELFStreamer::emitAMDGPULDS(MCSymbol *Symbol, unsigned Size,
725                                             Align Alignment) {
726   MCSymbolELF *SymbolELF = cast<MCSymbolELF>(Symbol);
727   SymbolELF->setType(ELF::STT_OBJECT);
728 
729   if (!SymbolELF->isBindingSet()) {
730     SymbolELF->setBinding(ELF::STB_GLOBAL);
731     SymbolELF->setExternal(true);
732   }
733 
734   if (SymbolELF->declareCommon(Size, Alignment.value(), true)) {
735     report_fatal_error("Symbol: " + Symbol->getName() +
736                        " redeclared as different type");
737   }
738 
739   SymbolELF->setIndex(ELF::SHN_AMDGPU_LDS);
740   SymbolELF->setSize(MCConstantExpr::create(Size, getContext()));
741 }
742 
743 bool AMDGPUTargetELFStreamer::EmitISAVersion() {
744   // Create two labels to mark the beginning and end of the desc field
745   // and a MCExpr to calculate the size of the desc field.
746   auto &Context = getContext();
747   auto *DescBegin = Context.createTempSymbol();
748   auto *DescEnd = Context.createTempSymbol();
749   auto *DescSZ = MCBinaryExpr::createSub(
750     MCSymbolRefExpr::create(DescEnd, Context),
751     MCSymbolRefExpr::create(DescBegin, Context), Context);
752 
753   EmitNote(ElfNote::NoteNameV2, DescSZ, ELF::NT_AMD_HSA_ISA_NAME,
754            [&](MCELFStreamer &OS) {
755              OS.emitLabel(DescBegin);
756              OS.emitBytes(getTargetID()->toString());
757              OS.emitLabel(DescEnd);
758            });
759   return true;
760 }
761 
762 bool AMDGPUTargetELFStreamer::EmitHSAMetadata(msgpack::Document &HSAMetadataDoc,
763                                               bool Strict) {
764   HSAMD::V3::MetadataVerifier Verifier(Strict);
765   if (!Verifier.verify(HSAMetadataDoc.getRoot()))
766     return false;
767 
768   std::string HSAMetadataString;
769   HSAMetadataDoc.writeToBlob(HSAMetadataString);
770 
771   // Create two labels to mark the beginning and end of the desc field
772   // and a MCExpr to calculate the size of the desc field.
773   auto &Context = getContext();
774   auto *DescBegin = Context.createTempSymbol();
775   auto *DescEnd = Context.createTempSymbol();
776   auto *DescSZ = MCBinaryExpr::createSub(
777       MCSymbolRefExpr::create(DescEnd, Context),
778       MCSymbolRefExpr::create(DescBegin, Context), Context);
779 
780   EmitNote(ElfNote::NoteNameV3, DescSZ, ELF::NT_AMDGPU_METADATA,
781            [&](MCELFStreamer &OS) {
782              OS.emitLabel(DescBegin);
783              OS.emitBytes(HSAMetadataString);
784              OS.emitLabel(DescEnd);
785            });
786   return true;
787 }
788 
789 bool AMDGPUTargetELFStreamer::EmitHSAMetadata(
790     const AMDGPU::HSAMD::Metadata &HSAMetadata) {
791   std::string HSAMetadataString;
792   if (HSAMD::toString(HSAMetadata, HSAMetadataString))
793     return false;
794 
795   // Create two labels to mark the beginning and end of the desc field
796   // and a MCExpr to calculate the size of the desc field.
797   auto &Context = getContext();
798   auto *DescBegin = Context.createTempSymbol();
799   auto *DescEnd = Context.createTempSymbol();
800   auto *DescSZ = MCBinaryExpr::createSub(
801     MCSymbolRefExpr::create(DescEnd, Context),
802     MCSymbolRefExpr::create(DescBegin, Context), Context);
803 
804   EmitNote(ElfNote::NoteNameV2, DescSZ, ELF::NT_AMD_HSA_METADATA,
805            [&](MCELFStreamer &OS) {
806              OS.emitLabel(DescBegin);
807              OS.emitBytes(HSAMetadataString);
808              OS.emitLabel(DescEnd);
809            });
810   return true;
811 }
812 
813 bool AMDGPUTargetELFStreamer::EmitCodeEnd(const MCSubtargetInfo &STI) {
814   const uint32_t Encoded_s_code_end = 0xbf9f0000;
815   const uint32_t Encoded_s_nop = 0xbf800000;
816   uint32_t Encoded_pad = Encoded_s_code_end;
817 
818   // Instruction cache line size in bytes.
819   const unsigned Log2CacheLineSize = 6;
820   const unsigned CacheLineSize = 1u << Log2CacheLineSize;
821 
822   // Extra padding amount in bytes to support prefetch mode 3.
823   unsigned FillSize = 3 * CacheLineSize;
824 
825   if (AMDGPU::isGFX90A(STI)) {
826     Encoded_pad = Encoded_s_nop;
827     FillSize = 16 * CacheLineSize;
828   }
829 
830   MCStreamer &OS = getStreamer();
831   OS.PushSection();
832   OS.emitValueToAlignment(CacheLineSize, Encoded_pad, 4);
833   for (unsigned I = 0; I < FillSize; I += 4)
834     OS.emitInt32(Encoded_pad);
835   OS.PopSection();
836   return true;
837 }
838 
839 void AMDGPUTargetELFStreamer::EmitAmdhsaKernelDescriptor(
840     const MCSubtargetInfo &STI, StringRef KernelName,
841     const amdhsa::kernel_descriptor_t &KernelDescriptor, uint64_t NextVGPR,
842     uint64_t NextSGPR, bool ReserveVCC, bool ReserveFlatScr) {
843   auto &Streamer = getStreamer();
844   auto &Context = Streamer.getContext();
845 
846   MCSymbolELF *KernelCodeSymbol = cast<MCSymbolELF>(
847       Context.getOrCreateSymbol(Twine(KernelName)));
848   MCSymbolELF *KernelDescriptorSymbol = cast<MCSymbolELF>(
849       Context.getOrCreateSymbol(Twine(KernelName) + Twine(".kd")));
850 
851   // Copy kernel descriptor symbol's binding, other and visibility from the
852   // kernel code symbol.
853   KernelDescriptorSymbol->setBinding(KernelCodeSymbol->getBinding());
854   KernelDescriptorSymbol->setOther(KernelCodeSymbol->getOther());
855   KernelDescriptorSymbol->setVisibility(KernelCodeSymbol->getVisibility());
856   // Kernel descriptor symbol's type and size are fixed.
857   KernelDescriptorSymbol->setType(ELF::STT_OBJECT);
858   KernelDescriptorSymbol->setSize(
859       MCConstantExpr::create(sizeof(KernelDescriptor), Context));
860 
861   // The visibility of the kernel code symbol must be protected or less to allow
862   // static relocations from the kernel descriptor to be used.
863   if (KernelCodeSymbol->getVisibility() == ELF::STV_DEFAULT)
864     KernelCodeSymbol->setVisibility(ELF::STV_PROTECTED);
865 
866   Streamer.emitLabel(KernelDescriptorSymbol);
867   Streamer.emitInt32(KernelDescriptor.group_segment_fixed_size);
868   Streamer.emitInt32(KernelDescriptor.private_segment_fixed_size);
869   Streamer.emitInt32(KernelDescriptor.kernarg_size);
870 
871   for (uint8_t Res : KernelDescriptor.reserved0)
872     Streamer.emitInt8(Res);
873 
874   // FIXME: Remove the use of VK_AMDGPU_REL64 in the expression below. The
875   // expression being created is:
876   //   (start of kernel code) - (start of kernel descriptor)
877   // It implies R_AMDGPU_REL64, but ends up being R_AMDGPU_ABS64.
878   Streamer.emitValue(MCBinaryExpr::createSub(
879       MCSymbolRefExpr::create(
880           KernelCodeSymbol, MCSymbolRefExpr::VK_AMDGPU_REL64, Context),
881       MCSymbolRefExpr::create(
882           KernelDescriptorSymbol, MCSymbolRefExpr::VK_None, Context),
883       Context),
884       sizeof(KernelDescriptor.kernel_code_entry_byte_offset));
885   for (uint8_t Res : KernelDescriptor.reserved1)
886     Streamer.emitInt8(Res);
887   Streamer.emitInt32(KernelDescriptor.compute_pgm_rsrc3);
888   Streamer.emitInt32(KernelDescriptor.compute_pgm_rsrc1);
889   Streamer.emitInt32(KernelDescriptor.compute_pgm_rsrc2);
890   Streamer.emitInt16(KernelDescriptor.kernel_code_properties);
891   for (uint8_t Res : KernelDescriptor.reserved2)
892     Streamer.emitInt8(Res);
893 }
894