xref: /freebsd/contrib/llvm-project/llvm/utils/TableGen/Basic/ARMTargetDefEmitter.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
1 //===- ARMTargetDefEmitter.cpp - Generate data about ARM Architectures ----===//
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 tablegen backend exports information about CPUs, FPUs, architectures,
10 // and features into a common format that can be used by both TargetParser and
11 // the ARM and AArch64 backends.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/ADT/DenseMap.h"
16 #include "llvm/ADT/StringSet.h"
17 #include "llvm/Support/Format.h"
18 #include "llvm/Support/FormatVariadic.h"
19 #include "llvm/TableGen/Error.h"
20 #include "llvm/TableGen/Record.h"
21 #include "llvm/TableGen/TableGenBackend.h"
22 #include <set>
23 #include <string>
24 
25 using namespace llvm;
26 
27 /// Collect the full set of implied features for a SubtargetFeature.
28 static void collectImpliedFeatures(std::set<const Record *> &SeenFeats,
29                                    const Record *Rec) {
30   assert(Rec->isSubClassOf("SubtargetFeature") &&
31          "Rec is not a SubtargetFeature");
32 
33   SeenFeats.insert(Rec);
34   for (const Record *Implied : Rec->getValueAsListOfDefs("Implies"))
35     collectImpliedFeatures(SeenFeats, Implied);
36 }
37 
38 static void checkFeatureTree(const Record *Root) {
39   std::set<const Record *> SeenFeats;
40   collectImpliedFeatures(SeenFeats, Root);
41 
42   // Check that each of the mandatory (implied) features which is an
43   // ExtensionWithMArch is also enabled by default.
44   auto DefaultExtsVec = Root->getValueAsListOfDefs("DefaultExts");
45   std::set<const Record *> DefaultExts{DefaultExtsVec.begin(),
46                                        DefaultExtsVec.end()};
47   for (const Record *Feat : SeenFeats) {
48     if (Feat->isSubClassOf("ExtensionWithMArch") && !DefaultExts.count(Feat))
49       PrintFatalError(Root->getLoc(),
50                       "ExtensionWithMArch " + Feat->getName() +
51                           " is implied (mandatory) as a SubtargetFeature, but "
52                           "is not present in DefaultExts");
53   }
54 }
55 
56 static void emitARMTargetDef(const RecordKeeper &RK, raw_ostream &OS) {
57   OS << "// Autogenerated by ARMTargetDefEmitter.cpp\n\n";
58 
59   // Look through all SubtargetFeature defs with the given FieldName, and
60   // collect the set of all Values that that FieldName is set to.
61   auto GatherSubtargetFeatureFieldValues = [&RK](StringRef FieldName) {
62     llvm::StringSet<> Set;
63     for (const Record *Rec : RK.getAllDerivedDefinitions("SubtargetFeature")) {
64       if (Rec->getValueAsString("FieldName") == FieldName) {
65         Set.insert(Rec->getValueAsString("Value"));
66       }
67     }
68     return Set;
69   };
70 
71   // Sort the extensions alphabetically, so they don't appear in tablegen order.
72   std::vector<const Record *> SortedExtensions =
73       RK.getAllDerivedDefinitions("Extension");
74   auto Alphabetical = [](const Record *A, const Record *B) -> bool {
75     const auto NameA = A->getValueAsString("Name");
76     const auto NameB = B->getValueAsString("Name");
77     return NameA.compare(NameB) < 0; // A lexographically less than B
78   };
79   sort(SortedExtensions, Alphabetical);
80 
81   // Cache Extension records for quick lookup.
82   DenseMap<StringRef, const Record *> ExtensionMap;
83   for (const Record *Rec : SortedExtensions) {
84     auto Name = Rec->getValueAsString("UserVisibleName");
85     if (Name.empty())
86       Name = Rec->getValueAsString("Name");
87     ExtensionMap[Name] = Rec;
88   }
89 
90   // The ARMProcFamilyEnum values are initialised by SubtargetFeature defs
91   // which set the ARMProcFamily field. We can generate the enum from these defs
92   // which look like this:
93   //
94   // def ProcA5      : SubtargetFeature<"a5", "ARMProcFamily", "CortexA5",
95   //                                    "Cortex-A5 ARM processors", []>;
96   OS << "#ifndef ARM_PROCESSOR_FAMILY\n"
97      << "#define ARM_PROCESSOR_FAMILY(ENUM)\n"
98      << "#endif\n\n";
99   const StringSet<> ARMProcFamilyVals =
100       GatherSubtargetFeatureFieldValues("ARMProcFamily");
101   for (const StringRef &Family : ARMProcFamilyVals.keys())
102     OS << "ARM_PROCESSOR_FAMILY(" << Family << ")\n";
103   OS << "\n#undef ARM_PROCESSOR_FAMILY\n\n";
104 
105   OS << "#ifndef ARM_ARCHITECTURE\n"
106      << "#define ARM_ARCHITECTURE(ENUM)\n"
107      << "#endif\n\n";
108   // This should correspond to instances of the Architecture tablegen class.
109   const StringSet<> ARMArchVals = GatherSubtargetFeatureFieldValues("ARMArch");
110   for (const StringRef &Arch : ARMArchVals.keys())
111     OS << "ARM_ARCHITECTURE(" << Arch << ")\n";
112   OS << "\n#undef ARM_ARCHITECTURE\n\n";
113 
114   // Currently only AArch64 (not ARM) is handled beyond this point.
115   if (!RK.getClass("Architecture64"))
116     return;
117 
118   // Emit the ArchExtKind enum
119   OS << "#ifdef EMIT_ARCHEXTKIND_ENUM\n"
120      << "enum ArchExtKind : unsigned {\n";
121   for (const Record *Rec : SortedExtensions) {
122     auto AEK = Rec->getValueAsString("ArchExtKindSpelling").upper();
123     OS << "  " << AEK << ",\n";
124   }
125   OS << "  AEK_NUM_EXTENSIONS\n"
126      << "};\n"
127      << "#undef EMIT_ARCHEXTKIND_ENUM\n"
128      << "#endif // EMIT_ARCHEXTKIND_ENUM\n";
129 
130   // Emit information for each defined Extension; used to build ArmExtKind.
131   OS << "#ifdef EMIT_EXTENSIONS\n"
132      << "inline constexpr ExtensionInfo Extensions[] = {\n";
133   for (const Record *Rec : SortedExtensions) {
134     auto AEK = Rec->getValueAsString("ArchExtKindSpelling").upper();
135     OS << "  ";
136     OS << "{\"" << Rec->getValueAsString("UserVisibleName") << "\"";
137     if (auto Alias = Rec->getValueAsString("UserVisibleAlias"); Alias.empty())
138       OS << ", {}";
139     else
140       OS << ", \"" << Alias << "\"";
141     OS << ", AArch64::" << AEK;
142     OS << ", \"" << Rec->getValueAsString("ArchFeatureName") << "\"";
143     OS << ", \"" << Rec->getValueAsString("Desc") << "\"";
144     OS << ", \"+" << Rec->getValueAsString("Name") << "\""; // posfeature
145     OS << ", \"-" << Rec->getValueAsString("Name") << "\""; // negfeature
146     OS << "},\n";
147   };
148   OS << "};\n"
149      << "#undef EMIT_EXTENSIONS\n"
150      << "#endif // EMIT_EXTENSIONS\n"
151      << "\n";
152 
153   // Emit FMV information
154   auto FMVExts = RK.getAllDerivedDefinitionsIfDefined("FMVExtension");
155   OS << "#ifdef EMIT_FMV_INFO\n"
156      << "const std::vector<llvm::AArch64::FMVInfo>& "
157         "llvm::AArch64::getFMVInfo() {\n"
158      << "  static std::vector<FMVInfo> I;\n"
159      << "  if(I.size()) return I;\n"
160      << "  I.reserve(" << FMVExts.size() << ");\n";
161   for (const Record *Rec : FMVExts) {
162     OS << "  I.emplace_back(";
163     OS << "\"" << Rec->getValueAsString("Name") << "\"";
164     OS << ", " << Rec->getValueAsString("FeatureBit");
165     OS << ", " << Rec->getValueAsString("PriorityBit");
166     auto FeatName = Rec->getValueAsString("BackendFeature");
167     const Record *FeatRec = ExtensionMap[FeatName];
168     if (FeatRec)
169       OS << ", " << FeatRec->getValueAsString("ArchExtKindSpelling").upper();
170     else
171       OS << ", std::nullopt";
172     OS << ");\n";
173   };
174   OS << "  return I;\n"
175      << "}\n"
176      << "#undef EMIT_FMV_INFO\n"
177      << "#endif // EMIT_FMV_INFO\n"
178      << "\n";
179 
180   // Emit extension dependencies
181   OS << "#ifdef EMIT_EXTENSION_DEPENDENCIES\n"
182      << "inline constexpr ExtensionDependency ExtensionDependencies[] = {\n";
183   for (const Record *Rec : SortedExtensions) {
184     auto LaterAEK = Rec->getValueAsString("ArchExtKindSpelling").upper();
185     for (const Record *I : Rec->getValueAsListOfDefs("Implies"))
186       if (auto EarlierAEK = I->getValueAsOptionalString("ArchExtKindSpelling"))
187         OS << "  {" << EarlierAEK->upper() << ", " << LaterAEK << "},\n";
188   }
189   // FIXME: Tablegen has the Subtarget Feature FeatureRCPC_IMMO which is implied
190   // by FeatureRCPC3 and in turn implies FeatureRCPC. The proper fix is to make
191   // FeatureRCPC_IMMO an Extension but that will expose it to the command line.
192   OS << "  {AEK_RCPC, AEK_RCPC3},\n";
193   OS << "};\n"
194      << "#undef EMIT_EXTENSION_DEPENDENCIES\n"
195      << "#endif // EMIT_EXTENSION_DEPENDENCIES\n"
196      << "\n";
197 
198   // Emit architecture information
199   OS << "#ifdef EMIT_ARCHITECTURES\n";
200 
201   // Return the C++ name of the of an ArchInfo object
202   auto ArchInfoName = [](int Major, int Minor,
203                          StringRef Profile) -> std::string {
204     return Minor == 0 ? "ARMV" + std::to_string(Major) + Profile.upper()
205                       : "ARMV" + std::to_string(Major) + "_" +
206                             std::to_string(Minor) + Profile.upper();
207   };
208 
209   auto Architectures = RK.getAllDerivedDefinitionsIfDefined("Architecture64");
210   std::vector<std::string> CppSpellings;
211   for (const Record *Rec : Architectures) {
212     const int Major = Rec->getValueAsInt("Major");
213     const int Minor = Rec->getValueAsInt("Minor");
214     const std::string ProfileLower = Rec->getValueAsString("Profile").str();
215     const std::string ProfileUpper = Rec->getValueAsString("Profile").upper();
216 
217     if (ProfileLower != "a" && ProfileLower != "r")
218       PrintFatalError(Rec->getLoc(),
219                       "error: Profile must be one of 'a' or 'r', got '" +
220                           ProfileLower + "'");
221 
222     // Name of the object in C++
223     const std::string CppSpelling = ArchInfoName(Major, Minor, ProfileUpper);
224     OS << "inline constexpr ArchInfo " << CppSpelling << " = {\n";
225     CppSpellings.push_back(std::move(CppSpelling));
226 
227     OS << llvm::format("  VersionTuple{%d, %d},\n", Major, Minor);
228     OS << llvm::format("  %sProfile,\n", ProfileUpper.c_str());
229 
230     // Name as spelled for -march.
231     if (Minor == 0)
232       OS << llvm::format("  \"armv%d-%s\",\n", Major, ProfileLower.c_str());
233     else
234       OS << llvm::format("  \"armv%d.%d-%s\",\n", Major, Minor,
235                          ProfileLower.c_str());
236 
237     // SubtargetFeature::Name, used for -target-feature. Here the "+" is added.
238     const auto TargetFeatureName = Rec->getValueAsString("Name");
239     OS << "  \"+" << TargetFeatureName << "\",\n";
240 
241     // Construct the list of default extensions
242     OS << "  (AArch64::ExtensionBitset({";
243     for (auto *E : Rec->getValueAsListOfDefs("DefaultExts")) {
244       OS << "AArch64::" << E->getValueAsString("ArchExtKindSpelling").upper()
245          << ", ";
246     }
247     OS << "}))\n";
248 
249     OS << "};\n";
250   }
251 
252   OS << "\n"
253      << "/// The set of all architectures\n"
254      << "static constexpr std::array<const ArchInfo *, " << CppSpellings.size()
255      << "> ArchInfos = {\n";
256   for (StringRef CppSpelling : CppSpellings)
257     OS << "  &" << CppSpelling << ",\n";
258   OS << "};\n";
259 
260   OS << "#undef EMIT_ARCHITECTURES\n"
261      << "#endif // EMIT_ARCHITECTURES\n"
262      << "\n";
263 
264   // Emit CPU Aliases
265   OS << "#ifdef EMIT_CPU_ALIAS\n"
266      << "inline constexpr Alias CpuAliases[] = {\n";
267 
268   llvm::StringSet<> Processors;
269   for (const Record *Rec : RK.getAllDerivedDefinitions("ProcessorModel"))
270     Processors.insert(Rec->getValueAsString("Name"));
271 
272   llvm::StringSet<> Aliases;
273   for (const Record *Rec : RK.getAllDerivedDefinitions("ProcessorAlias")) {
274     auto Name = Rec->getValueAsString("Name");
275     auto Alias = Rec->getValueAsString("Alias");
276     if (!Processors.contains(Alias))
277       PrintFatalError(
278           Rec, "Alias '" + Name + "' references a non-existent ProcessorModel '" + Alias + "'");
279     if (Processors.contains(Name))
280       PrintFatalError(
281           Rec, "Alias '" + Name + "' duplicates an existing ProcessorModel");
282     if (!Aliases.insert(Name).second)
283       PrintFatalError(
284           Rec, "Alias '" + Name + "' duplicates an existing ProcessorAlias");
285 
286     OS << llvm::formatv(R"(  { "{0}", "{1}" },)", Name, Alias) << '\n';
287   }
288 
289   OS << "};\n"
290      << "#undef EMIT_CPU_ALIAS\n"
291      << "#endif // EMIT_CPU_ALIAS\n"
292      << "\n";
293 
294   // Emit CPU information
295   OS << "#ifdef EMIT_CPU_INFO\n"
296      << "inline constexpr CpuInfo CpuInfos[] = {\n";
297 
298   for (const Record *Rec : RK.getAllDerivedDefinitions("ProcessorModel")) {
299     auto Name = Rec->getValueAsString("Name");
300     auto Features = Rec->getValueAsListOfDefs("Features");
301 
302     // "apple-latest" is backend-only, should not be accepted by TargetParser.
303     if (Name == "apple-latest")
304       continue;
305 
306     const Record *Arch;
307     if (Name == "generic") {
308       // "generic" is an exception. It does not have an architecture, and there
309       // are tests that depend on e.g. -mattr=-v8.4a meaning HasV8_0aOps==false.
310       // However, in TargetParser CPUInfo, it is written as 8.0-A.
311       Arch = RK.getDef("HasV8_0aOps");
312     } else {
313       // Search for an Architecture64 in the list of features.
314       auto IsArch = [](const Record *F) {
315         return F->isSubClassOf("Architecture64");
316       };
317       auto ArchIter = llvm::find_if(Features, IsArch);
318       if (ArchIter == Features.end())
319         PrintFatalError(Rec, "Features must include an Architecture64.");
320       Arch = *ArchIter;
321 
322       // Check there is only one Architecture in the list.
323       if (llvm::count_if(Features, IsArch) > 1)
324         PrintFatalError(Rec, "Features has multiple Architecture64 entries");
325     }
326 
327     auto Major = Arch->getValueAsInt("Major");
328     auto Minor = Arch->getValueAsInt("Minor");
329     auto Profile = Arch->getValueAsString("Profile");
330     auto ArchInfo = ArchInfoName(Major, Minor, Profile);
331 
332     checkFeatureTree(Arch);
333 
334     OS << "  {\n"
335        << "    \"" << Name << "\",\n"
336        << "    " << ArchInfo << ",\n"
337        << "    AArch64::ExtensionBitset({\n";
338 
339     // Keep track of extensions we have seen
340     StringSet<> SeenExts;
341     for (const Record *E : Rec->getValueAsListOfDefs("Features"))
342       // Only process subclasses of Extension
343       if (E->isSubClassOf("Extension")) {
344         const auto AEK = E->getValueAsString("ArchExtKindSpelling").upper();
345         if (!SeenExts.insert(AEK).second)
346           PrintFatalError(Rec, "feature already added: " + E->getName());
347         OS << "      AArch64::" << AEK << ",\n";
348       }
349     OS << "    })\n"
350        << "  },\n";
351   }
352   OS << "};\n";
353 
354   OS << "#undef EMIT_CPU_INFO\n"
355      << "#endif // EMIT_CPU_INFO\n"
356      << "\n";
357 }
358 
359 static TableGen::Emitter::Opt
360     X("gen-arm-target-def", emitARMTargetDef,
361       "Generate the ARM or AArch64 Architecture information header.");
362