1 //===--- AMDGPU.h - Declare AMDGPU target feature support -------*- 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 // This file declares AMDGPU TargetInfo objects.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LIB_BASIC_TARGETS_AMDGPU_H
14 #define LLVM_CLANG_LIB_BASIC_TARGETS_AMDGPU_H
15 
16 #include "clang/Basic/TargetID.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "clang/Basic/TargetOptions.h"
19 #include "llvm/ADT/StringSet.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/Support/Compiler.h"
22 #include "llvm/Support/TargetParser.h"
23 
24 namespace clang {
25 namespace targets {
26 
27 class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
28 
29   static const Builtin::Info BuiltinInfo[];
30   static const char *const GCCRegNames[];
31 
32   enum AddrSpace {
33     Generic = 0,
34     Global = 1,
35     Local = 3,
36     Constant = 4,
37     Private = 5
38   };
39   static const LangASMap AMDGPUDefIsGenMap;
40   static const LangASMap AMDGPUDefIsPrivMap;
41 
42   llvm::AMDGPU::GPUKind GPUKind;
43   unsigned GPUFeatures;
44   unsigned WavefrontSize;
45 
46   /// Target ID is device name followed by optional feature name postfixed
47   /// by plus or minus sign delimitted by colon, e.g. gfx908:xnack+:sramecc-.
48   /// If the target ID contains feature+, map it to true.
49   /// If the target ID contains feature-, map it to false.
50   /// If the target ID does not contain a feature (default), do not map it.
51   llvm::StringMap<bool> OffloadArchFeatures;
52   std::string TargetID;
53 
54   bool hasFP64() const {
55     return getTriple().getArch() == llvm::Triple::amdgcn ||
56            !!(GPUFeatures & llvm::AMDGPU::FEATURE_FP64);
57   }
58 
59   /// Has fast fma f32
60   bool hasFastFMAF() const {
61     return !!(GPUFeatures & llvm::AMDGPU::FEATURE_FAST_FMA_F32);
62   }
63 
64   /// Has fast fma f64
65   bool hasFastFMA() const {
66     return getTriple().getArch() == llvm::Triple::amdgcn;
67   }
68 
69   bool hasFMAF() const {
70     return getTriple().getArch() == llvm::Triple::amdgcn ||
71            !!(GPUFeatures & llvm::AMDGPU::FEATURE_FMA);
72   }
73 
74   bool hasFullRateDenormalsF32() const {
75     return !!(GPUFeatures & llvm::AMDGPU::FEATURE_FAST_DENORMAL_F32);
76   }
77 
78   bool hasLDEXPF() const {
79     return getTriple().getArch() == llvm::Triple::amdgcn ||
80            !!(GPUFeatures & llvm::AMDGPU::FEATURE_LDEXP);
81   }
82 
83   static bool isAMDGCN(const llvm::Triple &TT) {
84     return TT.getArch() == llvm::Triple::amdgcn;
85   }
86 
87   static bool isR600(const llvm::Triple &TT) {
88     return TT.getArch() == llvm::Triple::r600;
89   }
90 
91 public:
92   AMDGPUTargetInfo(const llvm::Triple &Triple, const TargetOptions &Opts);
93 
94   void setAddressSpaceMap(bool DefaultIsPrivate);
95 
96   void adjust(LangOptions &Opts) override;
97 
98   uint64_t getPointerWidthV(unsigned AddrSpace) const override {
99     if (isR600(getTriple()))
100       return 32;
101 
102     if (AddrSpace == Private || AddrSpace == Local)
103       return 32;
104 
105     return 64;
106   }
107 
108   uint64_t getPointerAlignV(unsigned AddrSpace) const override {
109     return getPointerWidthV(AddrSpace);
110   }
111 
112   uint64_t getMaxPointerWidth() const override {
113     return getTriple().getArch() == llvm::Triple::amdgcn ? 64 : 32;
114   }
115 
116   const char *getClobbers() const override { return ""; }
117 
118   ArrayRef<const char *> getGCCRegNames() const override;
119 
120   ArrayRef<TargetInfo::GCCRegAlias> getGCCRegAliases() const override {
121     return None;
122   }
123 
124   /// Accepted register names: (n, m is unsigned integer, n < m)
125   /// v
126   /// s
127   /// a
128   /// {vn}, {v[n]}
129   /// {sn}, {s[n]}
130   /// {an}, {a[n]}
131   /// {S} , where S is a special register name
132   ////{v[n:m]}
133   /// {s[n:m]}
134   /// {a[n:m]}
135   bool validateAsmConstraint(const char *&Name,
136                              TargetInfo::ConstraintInfo &Info) const override {
137     static const ::llvm::StringSet<> SpecialRegs({
138         "exec", "vcc", "flat_scratch", "m0", "scc", "tba", "tma",
139         "flat_scratch_lo", "flat_scratch_hi", "vcc_lo", "vcc_hi", "exec_lo",
140         "exec_hi", "tma_lo", "tma_hi", "tba_lo", "tba_hi",
141     });
142 
143     switch (*Name) {
144     case 'I':
145       Info.setRequiresImmediate(-16, 64);
146       return true;
147     case 'J':
148       Info.setRequiresImmediate(-32768, 32767);
149       return true;
150     case 'A':
151     case 'B':
152     case 'C':
153       Info.setRequiresImmediate();
154       return true;
155     default:
156       break;
157     }
158 
159     StringRef S(Name);
160 
161     if (S == "DA" || S == "DB") {
162       Name++;
163       Info.setRequiresImmediate();
164       return true;
165     }
166 
167     bool HasLeftParen = false;
168     if (S.front() == '{') {
169       HasLeftParen = true;
170       S = S.drop_front();
171     }
172     if (S.empty())
173       return false;
174     if (S.front() != 'v' && S.front() != 's' && S.front() != 'a') {
175       if (!HasLeftParen)
176         return false;
177       auto E = S.find('}');
178       if (!SpecialRegs.count(S.substr(0, E)))
179         return false;
180       S = S.drop_front(E + 1);
181       if (!S.empty())
182         return false;
183       // Found {S} where S is a special register.
184       Info.setAllowsRegister();
185       Name = S.data() - 1;
186       return true;
187     }
188     S = S.drop_front();
189     if (!HasLeftParen) {
190       if (!S.empty())
191         return false;
192       // Found s, v or a.
193       Info.setAllowsRegister();
194       Name = S.data() - 1;
195       return true;
196     }
197     bool HasLeftBracket = false;
198     if (!S.empty() && S.front() == '[') {
199       HasLeftBracket = true;
200       S = S.drop_front();
201     }
202     unsigned long long N;
203     if (S.empty() || consumeUnsignedInteger(S, 10, N))
204       return false;
205     if (!S.empty() && S.front() == ':') {
206       if (!HasLeftBracket)
207         return false;
208       S = S.drop_front();
209       unsigned long long M;
210       if (consumeUnsignedInteger(S, 10, M) || N >= M)
211         return false;
212     }
213     if (HasLeftBracket) {
214       if (S.empty() || S.front() != ']')
215         return false;
216       S = S.drop_front();
217     }
218     if (S.empty() || S.front() != '}')
219       return false;
220     S = S.drop_front();
221     if (!S.empty())
222       return false;
223     // Found {vn}, {sn}, {an}, {v[n]}, {s[n]}, {a[n]}, {v[n:m]}, {s[n:m]}
224     // or {a[n:m]}.
225     Info.setAllowsRegister();
226     Name = S.data() - 1;
227     return true;
228   }
229 
230   // \p Constraint will be left pointing at the last character of
231   // the constraint.  In practice, it won't be changed unless the
232   // constraint is longer than one character.
233   std::string convertConstraint(const char *&Constraint) const override {
234 
235     StringRef S(Constraint);
236     if (S == "DA" || S == "DB") {
237       return std::string("^") + std::string(Constraint++, 2);
238     }
239 
240     const char *Begin = Constraint;
241     TargetInfo::ConstraintInfo Info("", "");
242     if (validateAsmConstraint(Constraint, Info))
243       return std::string(Begin).substr(0, Constraint - Begin + 1);
244 
245     Constraint = Begin;
246     return std::string(1, *Constraint);
247   }
248 
249   bool
250   initFeatureMap(llvm::StringMap<bool> &Features, DiagnosticsEngine &Diags,
251                  StringRef CPU,
252                  const std::vector<std::string> &FeatureVec) const override;
253 
254   ArrayRef<Builtin::Info> getTargetBuiltins() const override;
255 
256   bool useFP16ConversionIntrinsics() const override { return false; }
257 
258   void getTargetDefines(const LangOptions &Opts,
259                         MacroBuilder &Builder) const override;
260 
261   BuiltinVaListKind getBuiltinVaListKind() const override {
262     return TargetInfo::CharPtrBuiltinVaList;
263   }
264 
265   bool isValidCPUName(StringRef Name) const override {
266     if (getTriple().getArch() == llvm::Triple::amdgcn)
267       return llvm::AMDGPU::parseArchAMDGCN(Name) != llvm::AMDGPU::GK_NONE;
268     return llvm::AMDGPU::parseArchR600(Name) != llvm::AMDGPU::GK_NONE;
269   }
270 
271   void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const override;
272 
273   bool setCPU(const std::string &Name) override {
274     if (getTriple().getArch() == llvm::Triple::amdgcn) {
275       GPUKind = llvm::AMDGPU::parseArchAMDGCN(Name);
276       GPUFeatures = llvm::AMDGPU::getArchAttrAMDGCN(GPUKind);
277     } else {
278       GPUKind = llvm::AMDGPU::parseArchR600(Name);
279       GPUFeatures = llvm::AMDGPU::getArchAttrR600(GPUKind);
280     }
281 
282     return GPUKind != llvm::AMDGPU::GK_NONE;
283   }
284 
285   void setSupportedOpenCLOpts() override {
286     auto &Opts = getSupportedOpenCLOpts();
287     Opts["cl_clang_storage_class_specifiers"] = true;
288     Opts["__cl_clang_variadic_functions"] = true;
289     Opts["__cl_clang_function_pointers"] = true;
290 
291     bool IsAMDGCN = isAMDGCN(getTriple());
292 
293     Opts["cl_khr_fp64"] = hasFP64();
294 
295     if (IsAMDGCN || GPUKind >= llvm::AMDGPU::GK_CEDAR) {
296       Opts["cl_khr_byte_addressable_store"] = true;
297       Opts["cl_khr_global_int32_base_atomics"] = true;
298       Opts["cl_khr_global_int32_extended_atomics"] = true;
299       Opts["cl_khr_local_int32_base_atomics"] = true;
300       Opts["cl_khr_local_int32_extended_atomics"] = true;
301     }
302 
303     if (IsAMDGCN) {
304       Opts["cl_khr_fp16"] = true;
305       Opts["cl_khr_int64_base_atomics"] = true;
306       Opts["cl_khr_int64_extended_atomics"] = true;
307       Opts["cl_khr_mipmap_image"] = true;
308       Opts["cl_khr_mipmap_image_writes"] = true;
309       Opts["cl_khr_subgroups"] = true;
310       Opts["cl_khr_3d_image_writes"] = true;
311       Opts["cl_amd_media_ops"] = true;
312       Opts["cl_amd_media_ops2"] = true;
313     }
314   }
315 
316   LangAS getOpenCLTypeAddrSpace(OpenCLTypeKind TK) const override {
317     switch (TK) {
318     case OCLTK_Image:
319       return LangAS::opencl_constant;
320 
321     case OCLTK_ClkEvent:
322     case OCLTK_Queue:
323     case OCLTK_ReserveID:
324       return LangAS::opencl_global;
325 
326     default:
327       return TargetInfo::getOpenCLTypeAddrSpace(TK);
328     }
329   }
330 
331   LangAS getOpenCLBuiltinAddressSpace(unsigned AS) const override {
332     switch (AS) {
333     case 0:
334       return LangAS::opencl_generic;
335     case 1:
336       return LangAS::opencl_global;
337     case 3:
338       return LangAS::opencl_local;
339     case 4:
340       return LangAS::opencl_constant;
341     case 5:
342       return LangAS::opencl_private;
343     default:
344       return getLangASFromTargetAS(AS);
345     }
346   }
347 
348   LangAS getCUDABuiltinAddressSpace(unsigned AS) const override {
349     return LangAS::Default;
350   }
351 
352   llvm::Optional<LangAS> getConstantAddressSpace() const override {
353     return getLangASFromTargetAS(Constant);
354   }
355 
356   /// \returns Target specific vtbl ptr address space.
357   unsigned getVtblPtrAddressSpace() const override {
358     return static_cast<unsigned>(Constant);
359   }
360 
361   /// \returns If a target requires an address within a target specific address
362   /// space \p AddressSpace to be converted in order to be used, then return the
363   /// corresponding target specific DWARF address space.
364   ///
365   /// \returns Otherwise return None and no conversion will be emitted in the
366   /// DWARF.
367   Optional<unsigned>
368   getDWARFAddressSpace(unsigned AddressSpace) const override {
369     const unsigned DWARF_Private = 1;
370     const unsigned DWARF_Local = 2;
371     if (AddressSpace == Private) {
372       return DWARF_Private;
373     } else if (AddressSpace == Local) {
374       return DWARF_Local;
375     } else {
376       return None;
377     }
378   }
379 
380   CallingConvCheckResult checkCallingConvention(CallingConv CC) const override {
381     switch (CC) {
382     default:
383       return CCCR_Warning;
384     case CC_C:
385     case CC_OpenCLKernel:
386       return CCCR_OK;
387     }
388   }
389 
390   // In amdgcn target the null pointer in global, constant, and generic
391   // address space has value 0 but in private and local address space has
392   // value ~0.
393   uint64_t getNullPointerValue(LangAS AS) const override {
394     // FIXME: Also should handle region.
395     return (AS == LangAS::opencl_local || AS == LangAS::opencl_private)
396       ? ~0 : 0;
397   }
398 
399   void setAuxTarget(const TargetInfo *Aux) override;
400 
401   bool hasExtIntType() const override { return true; }
402 
403   // Record offload arch features since they are needed for defining the
404   // pre-defined macros.
405   bool handleTargetFeatures(std::vector<std::string> &Features,
406                             DiagnosticsEngine &Diags) override {
407     auto TargetIDFeatures =
408         getAllPossibleTargetIDFeatures(getTriple(), getArchNameAMDGCN(GPUKind));
409     llvm::for_each(Features, [&](const auto &F) {
410       assert(F.front() == '+' || F.front() == '-');
411       if (F == "+wavefrontsize64")
412         WavefrontSize = 64;
413       bool IsOn = F.front() == '+';
414       StringRef Name = StringRef(F).drop_front();
415       if (llvm::find(TargetIDFeatures, Name) == TargetIDFeatures.end())
416         return;
417       assert(OffloadArchFeatures.find(Name) == OffloadArchFeatures.end());
418       OffloadArchFeatures[Name] = IsOn;
419     });
420     return true;
421   }
422 
423   Optional<std::string> getTargetID() const override {
424     if (!isAMDGCN(getTriple()))
425       return llvm::None;
426     // When -target-cpu is not set, we assume generic code that it is valid
427     // for all GPU and use an empty string as target ID to represent that.
428     if (GPUKind == llvm::AMDGPU::GK_NONE)
429       return std::string("");
430     return getCanonicalTargetID(getArchNameAMDGCN(GPUKind),
431                                 OffloadArchFeatures);
432   }
433 };
434 
435 } // namespace targets
436 } // namespace clang
437 
438 #endif // LLVM_CLANG_LIB_BASIC_TARGETS_AMDGPU_H
439