1 //===-- AArch64TargetParser - Parser for AArch64 features -------*- 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 implements a target parser to recognise AArch64 hardware features
10 // such as FPU/CPU/ARCH and extension names.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/TargetParser/AArch64TargetParser.h"
15 #include "llvm/TargetParser/ARMTargetParserCommon.h"
16 #include "llvm/TargetParser/Triple.h"
17 #include <cctype>
18 
19 using namespace llvm;
20 
21 static unsigned checkArchVersion(llvm::StringRef Arch) {
22   if (Arch.size() >= 2 && Arch[0] == 'v' && std::isdigit(Arch[1]))
23     return (Arch[1] - 48);
24   return 0;
25 }
26 
27 std::optional<AArch64::ArchInfo> AArch64::getArchForCpu(StringRef CPU) {
28   if (CPU == "generic")
29     return ARMV8A;
30 
31   // Note: this now takes cpu aliases into account
32   std::optional<CpuInfo> Cpu = parseCpu(CPU);
33   if (!Cpu)
34     return {};
35   return Cpu->Arch;
36 }
37 
38 std::optional<AArch64::ArchInfo> AArch64::ArchInfo::findBySubArch(StringRef SubArch) {
39   for (const auto *A : AArch64::ArchInfos)
40     if (A->getSubArch() == SubArch)
41       return *A;
42   return {};
43 }
44 
45 uint64_t AArch64::getCpuSupportsMask(ArrayRef<StringRef> FeatureStrs) {
46   uint64_t FeaturesMask = 0;
47   for (const StringRef &FeatureStr : FeatureStrs) {
48     for (const auto &E : llvm::AArch64::Extensions)
49       if (FeatureStr == E.Name) {
50         FeaturesMask |= (1ULL << E.CPUFeature);
51         break;
52       }
53   }
54   return FeaturesMask;
55 }
56 
57 bool AArch64::getExtensionFeatures(uint64_t InputExts,
58                                    std::vector<StringRef> &Features) {
59   for (const auto &E : Extensions)
60     /* INVALID and NONE have no feature name. */
61     if ((InputExts & E.ID) && !E.Feature.empty())
62       Features.push_back(E.Feature);
63 
64   return true;
65 }
66 
67 StringRef AArch64::resolveCPUAlias(StringRef Name) {
68   for (const auto &A : CpuAliases)
69     if (A.Alias == Name)
70       return A.Name;
71   return Name;
72 }
73 
74 StringRef AArch64::getArchExtFeature(StringRef ArchExt) {
75   if (ArchExt.startswith("no")) {
76     StringRef ArchExtBase(ArchExt.substr(2));
77     for (const auto &AE : Extensions) {
78       if (!AE.NegFeature.empty() && ArchExtBase == AE.Name)
79         return AE.NegFeature;
80     }
81   }
82 
83   for (const auto &AE : Extensions)
84     if (!AE.Feature.empty() && ArchExt == AE.Name)
85       return AE.Feature;
86   return StringRef();
87 }
88 
89 void AArch64::fillValidCPUArchList(SmallVectorImpl<StringRef> &Values) {
90   for (const auto &C : CpuInfos)
91       Values.push_back(C.Name);
92 
93   for (const auto &Alias : CpuAliases)
94     Values.push_back(Alias.Alias);
95 }
96 
97 bool AArch64::isX18ReservedByDefault(const Triple &TT) {
98   return TT.isAndroid() || TT.isOSDarwin() || TT.isOSFuchsia() ||
99          TT.isOSWindows() || TT.isOHOSFamily();
100 }
101 
102 // Allows partial match, ex. "v8a" matches "armv8a".
103 std::optional<AArch64::ArchInfo> AArch64::parseArch(StringRef Arch) {
104   Arch = llvm::ARM::getCanonicalArchName(Arch);
105   if (checkArchVersion(Arch) < 8)
106     return {};
107 
108   StringRef Syn = llvm::ARM::getArchSynonym(Arch);
109   for (const auto *A : ArchInfos) {
110     if (A->Name.endswith(Syn))
111       return *A;
112   }
113   return {};
114 }
115 
116 std::optional<AArch64::ExtensionInfo> AArch64::parseArchExtension(StringRef ArchExt) {
117   for (const auto &A : Extensions) {
118     if (ArchExt == A.Name)
119       return A;
120   }
121   return {};
122 }
123 
124 std::optional<AArch64::CpuInfo> AArch64::parseCpu(StringRef Name) {
125   // Resolve aliases first.
126   Name = resolveCPUAlias(Name);
127 
128   // Then find the CPU name.
129   for (const auto &C : CpuInfos)
130     if (Name == C.Name)
131       return C;
132 
133   return {};
134 }
135