xref: /freebsd/contrib/llvm-project/clang/lib/Basic/TargetID.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
1 //===--- TargetID.cpp - Utilities for parsing target ID -------------------===//
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 "clang/Basic/TargetID.h"
10 #include "llvm/ADT/STLExtras.h"
11 #include "llvm/ADT/SmallSet.h"
12 #include "llvm/TargetParser/TargetParser.h"
13 #include "llvm/TargetParser/Triple.h"
14 #include <map>
15 #include <optional>
16 
17 namespace clang {
18 
19 static llvm::SmallVector<llvm::StringRef, 4>
20 getAllPossibleAMDGPUTargetIDFeatures(const llvm::Triple &T,
21                                      llvm::StringRef Proc) {
22   // Entries in returned vector should be in alphabetical order.
23   llvm::SmallVector<llvm::StringRef, 4> Ret;
24   auto ProcKind = T.isAMDGCN() ? llvm::AMDGPU::parseArchAMDGCN(Proc)
25                                : llvm::AMDGPU::parseArchR600(Proc);
26   if (ProcKind == llvm::AMDGPU::GK_NONE)
27     return Ret;
28   auto Features = T.isAMDGCN() ? llvm::AMDGPU::getArchAttrAMDGCN(ProcKind)
29                                : llvm::AMDGPU::getArchAttrR600(ProcKind);
30   if (Features & llvm::AMDGPU::FEATURE_SRAMECC)
31     Ret.push_back("sramecc");
32   if (Features & llvm::AMDGPU::FEATURE_XNACK)
33     Ret.push_back("xnack");
34   return Ret;
35 }
36 
37 llvm::SmallVector<llvm::StringRef, 4>
38 getAllPossibleTargetIDFeatures(const llvm::Triple &T,
39                                llvm::StringRef Processor) {
40   llvm::SmallVector<llvm::StringRef, 4> Ret;
41   if (T.isAMDGPU())
42     return getAllPossibleAMDGPUTargetIDFeatures(T, Processor);
43   return Ret;
44 }
45 
46 /// Returns canonical processor name or empty string if \p Processor is invalid.
47 static llvm::StringRef getCanonicalProcessorName(const llvm::Triple &T,
48                                                  llvm::StringRef Processor) {
49   if (T.isAMDGPU())
50     return llvm::AMDGPU::getCanonicalArchName(T, Processor);
51   return Processor;
52 }
53 
54 llvm::StringRef getProcessorFromTargetID(const llvm::Triple &T,
55                                          llvm::StringRef TargetID) {
56   auto Split = TargetID.split(':');
57   return getCanonicalProcessorName(T, Split.first);
58 }
59 
60 // Parse a target ID with format checking only. Do not check whether processor
61 // name or features are valid for the processor.
62 //
63 // A target ID is a processor name followed by a list of target features
64 // delimited by colon. Each target feature is a string post-fixed by a plus
65 // or minus sign, e.g. gfx908:sramecc+:xnack-.
66 static std::optional<llvm::StringRef>
67 parseTargetIDWithFormatCheckingOnly(llvm::StringRef TargetID,
68                                     llvm::StringMap<bool> *FeatureMap) {
69   llvm::StringRef Processor;
70 
71   if (TargetID.empty())
72     return llvm::StringRef();
73 
74   auto Split = TargetID.split(':');
75   Processor = Split.first;
76   if (Processor.empty())
77     return std::nullopt;
78 
79   auto Features = Split.second;
80   if (Features.empty())
81     return Processor;
82 
83   llvm::StringMap<bool> LocalFeatureMap;
84   if (!FeatureMap)
85     FeatureMap = &LocalFeatureMap;
86 
87   while (!Features.empty()) {
88     auto Splits = Features.split(':');
89     auto Sign = Splits.first.back();
90     auto Feature = Splits.first.drop_back();
91     if (Sign != '+' && Sign != '-')
92       return std::nullopt;
93     bool IsOn = Sign == '+';
94     // Each feature can only show up at most once in target ID.
95     if (!FeatureMap->try_emplace(Feature, IsOn).second)
96       return std::nullopt;
97     Features = Splits.second;
98   }
99   return Processor;
100 }
101 
102 std::optional<llvm::StringRef>
103 parseTargetID(const llvm::Triple &T, llvm::StringRef TargetID,
104               llvm::StringMap<bool> *FeatureMap) {
105   auto OptionalProcessor =
106       parseTargetIDWithFormatCheckingOnly(TargetID, FeatureMap);
107 
108   if (!OptionalProcessor)
109     return std::nullopt;
110 
111   llvm::StringRef Processor = getCanonicalProcessorName(T, *OptionalProcessor);
112   if (Processor.empty())
113     return std::nullopt;
114 
115   llvm::SmallSet<llvm::StringRef, 4> AllFeatures(
116       llvm::from_range, getAllPossibleTargetIDFeatures(T, Processor));
117 
118   for (auto &&F : *FeatureMap)
119     if (!AllFeatures.count(F.first()))
120       return std::nullopt;
121 
122   return Processor;
123 }
124 
125 // A canonical target ID is a target ID containing a canonical processor name
126 // and features in alphabetical order.
127 std::string getCanonicalTargetID(llvm::StringRef Processor,
128                                  const llvm::StringMap<bool> &Features) {
129   std::string TargetID = Processor.str();
130   std::map<const llvm::StringRef, bool> OrderedMap;
131   for (const auto &F : Features)
132     OrderedMap[F.first()] = F.second;
133   for (const auto &F : OrderedMap)
134     TargetID = TargetID + ':' + F.first.str() + (F.second ? "+" : "-");
135   return TargetID;
136 }
137 
138 // For a specific processor, a feature either shows up in all target IDs, or
139 // does not show up in any target IDs. Otherwise the target ID combination
140 // is invalid.
141 std::optional<std::pair<llvm::StringRef, llvm::StringRef>>
142 getConflictTargetIDCombination(const std::set<llvm::StringRef> &TargetIDs) {
143   struct Info {
144     llvm::StringRef TargetID;
145     llvm::StringMap<bool> Features;
146     Info(llvm::StringRef TargetID, const llvm::StringMap<bool> &Features)
147         : TargetID(TargetID), Features(Features) {}
148   };
149   llvm::StringMap<Info> FeatureMap;
150   for (auto &&ID : TargetIDs) {
151     llvm::StringMap<bool> Features;
152     llvm::StringRef Proc = *parseTargetIDWithFormatCheckingOnly(ID, &Features);
153     auto [Loc, Inserted] = FeatureMap.try_emplace(Proc, ID, Features);
154     if (!Inserted) {
155       auto &ExistingFeatures = Loc->second.Features;
156       if (llvm::any_of(Features, [&](auto &F) {
157             return ExistingFeatures.count(F.first()) == 0;
158           }))
159         return std::make_pair(Loc->second.TargetID, ID);
160     }
161   }
162   return std::nullopt;
163 }
164 
165 bool isCompatibleTargetID(llvm::StringRef Provided, llvm::StringRef Requested) {
166   llvm::StringMap<bool> ProvidedFeatures, RequestedFeatures;
167   llvm::StringRef ProvidedProc =
168       *parseTargetIDWithFormatCheckingOnly(Provided, &ProvidedFeatures);
169   llvm::StringRef RequestedProc =
170       *parseTargetIDWithFormatCheckingOnly(Requested, &RequestedFeatures);
171   if (ProvidedProc != RequestedProc)
172     return false;
173   for (const auto &F : ProvidedFeatures) {
174     auto Loc = RequestedFeatures.find(F.first());
175     // The default (unspecified) value of a feature is 'All', which can match
176     // either 'On' or 'Off'.
177     if (Loc == RequestedFeatures.end())
178       return false;
179     // If a feature is specified, it must have exact match.
180     if (Loc->second != F.second)
181       return false;
182   }
183   return true;
184 }
185 
186 } // namespace clang
187