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/SmallSet.h"
11#include "llvm/Support/raw_ostream.h"
12#include "llvm/TargetParser/TargetParser.h"
13#include "llvm/TargetParser/Triple.h"
14#include <map>
15#include <optional>
16
17namespace clang {
18
19static llvm::SmallVector<llvm::StringRef, 4>
20getAllPossibleAMDGPUTargetIDFeatures(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(CPU: Proc)
25 : llvm::AMDGPU::parseArchR600(CPU: Proc);
26 if (ProcKind == llvm::AMDGPU::GK_NONE)
27 return Ret;
28 auto Features = T.isAMDGCN() ? llvm::AMDGPU::getArchAttrAMDGCN(AK: ProcKind)
29 : llvm::AMDGPU::getArchAttrR600(AK: ProcKind);
30 if (Features & llvm::AMDGPU::FEATURE_SRAMECC)
31 Ret.push_back(Elt: "sramecc");
32 if (Features & llvm::AMDGPU::FEATURE_XNACK)
33 Ret.push_back(Elt: "xnack");
34 return Ret;
35}
36
37llvm::SmallVector<llvm::StringRef, 4>
38getAllPossibleTargetIDFeatures(const llvm::Triple &T,
39 llvm::StringRef Processor) {
40 llvm::SmallVector<llvm::StringRef, 4> Ret;
41 if (T.isAMDGPU())
42 return getAllPossibleAMDGPUTargetIDFeatures(T, Proc: Processor);
43 return Ret;
44}
45
46/// Returns canonical processor name or empty string if \p Processor is invalid.
47static llvm::StringRef getCanonicalProcessorName(const llvm::Triple &T,
48 llvm::StringRef Processor) {
49 if (T.isAMDGPU())
50 return llvm::AMDGPU::getCanonicalArchName(T, Arch: Processor);
51 return Processor;
52}
53
54llvm::StringRef getProcessorFromTargetID(const llvm::Triple &T,
55 llvm::StringRef TargetID) {
56 auto Split = TargetID.split(Separator: ':');
57 return getCanonicalProcessorName(T, Processor: 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-.
66static std::optional<llvm::StringRef>
67parseTargetIDWithFormatCheckingOnly(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(Separator: ':');
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(Separator: ':');
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 auto Loc = FeatureMap->find(Key: Feature);
95 // Each feature can only show up at most once in target ID.
96 if (Loc != FeatureMap->end())
97 return std::nullopt;
98 (*FeatureMap)[Feature] = IsOn;
99 Features = Splits.second;
100 }
101 return Processor;
102}
103
104std::optional<llvm::StringRef>
105parseTargetID(const llvm::Triple &T, llvm::StringRef TargetID,
106 llvm::StringMap<bool> *FeatureMap) {
107 auto OptionalProcessor =
108 parseTargetIDWithFormatCheckingOnly(TargetID, FeatureMap);
109
110 if (!OptionalProcessor)
111 return std::nullopt;
112
113 llvm::StringRef Processor = getCanonicalProcessorName(T, Processor: *OptionalProcessor);
114 if (Processor.empty())
115 return std::nullopt;
116
117 llvm::SmallSet<llvm::StringRef, 4> AllFeatures;
118 for (auto &&F : getAllPossibleTargetIDFeatures(T, Processor))
119 AllFeatures.insert(V: F);
120
121 for (auto &&F : *FeatureMap)
122 if (!AllFeatures.count(V: F.first()))
123 return std::nullopt;
124
125 return Processor;
126}
127
128// A canonical target ID is a target ID containing a canonical processor name
129// and features in alphabetical order.
130std::string getCanonicalTargetID(llvm::StringRef Processor,
131 const llvm::StringMap<bool> &Features) {
132 std::string TargetID = Processor.str();
133 std::map<const llvm::StringRef, bool> OrderedMap;
134 for (const auto &F : Features)
135 OrderedMap[F.first()] = F.second;
136 for (const auto &F : OrderedMap)
137 TargetID = TargetID + ':' + F.first.str() + (F.second ? "+" : "-");
138 return TargetID;
139}
140
141// For a specific processor, a feature either shows up in all target IDs, or
142// does not show up in any target IDs. Otherwise the target ID combination
143// is invalid.
144std::optional<std::pair<llvm::StringRef, llvm::StringRef>>
145getConflictTargetIDCombination(const std::set<llvm::StringRef> &TargetIDs) {
146 struct Info {
147 llvm::StringRef TargetID;
148 llvm::StringMap<bool> Features;
149 };
150 llvm::StringMap<Info> FeatureMap;
151 for (auto &&ID : TargetIDs) {
152 llvm::StringMap<bool> Features;
153 llvm::StringRef Proc = *parseTargetIDWithFormatCheckingOnly(TargetID: ID, FeatureMap: &Features);
154 auto Loc = FeatureMap.find(Key: Proc);
155 if (Loc == FeatureMap.end())
156 FeatureMap[Proc] = Info{.TargetID: ID, .Features: Features};
157 else {
158 auto &ExistingFeatures = Loc->second.Features;
159 if (llvm::any_of(Range&: Features, P: [&](auto &F) {
160 return ExistingFeatures.count(F.first()) == 0;
161 }))
162 return std::make_pair(x&: Loc->second.TargetID, y: ID);
163 }
164 }
165 return std::nullopt;
166}
167
168bool isCompatibleTargetID(llvm::StringRef Provided, llvm::StringRef Requested) {
169 llvm::StringMap<bool> ProvidedFeatures, RequestedFeatures;
170 llvm::StringRef ProvidedProc =
171 *parseTargetIDWithFormatCheckingOnly(TargetID: Provided, FeatureMap: &ProvidedFeatures);
172 llvm::StringRef RequestedProc =
173 *parseTargetIDWithFormatCheckingOnly(TargetID: Requested, FeatureMap: &RequestedFeatures);
174 if (ProvidedProc != RequestedProc)
175 return false;
176 for (const auto &F : ProvidedFeatures) {
177 auto Loc = RequestedFeatures.find(Key: F.first());
178 // The default (unspecified) value of a feature is 'All', which can match
179 // either 'On' or 'Off'.
180 if (Loc == RequestedFeatures.end())
181 return false;
182 // If a feature is specified, it must have exact match.
183 if (Loc->second != F.second)
184 return false;
185 }
186 return true;
187}
188
189} // namespace clang
190