1 //===- SubtargetFeatureInfo.h - Helpers for subtarget 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 #ifndef LLVM_UTIL_TABLEGEN_SUBTARGETFEATUREINFO_H
10 #define LLVM_UTIL_TABLEGEN_SUBTARGETFEATUREINFO_H
11 
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/TableGen/Record.h"
14 #include <map>
15 #include <string>
16 #include <utility>
17 #include <vector>
18 
19 namespace llvm {
20 struct SubtargetFeatureInfo;
21 using SubtargetFeatureInfoMap = std::map<Record *, SubtargetFeatureInfo, LessRecordByID>;
22 
23 /// Helper class for storing information on a subtarget feature which
24 /// participates in instruction matching.
25 struct SubtargetFeatureInfo {
26   /// The predicate record for this feature.
27   Record *TheDef;
28 
29   /// An unique index assigned to represent this feature.
30   uint64_t Index;
31 
32   SubtargetFeatureInfo(Record *D, uint64_t Idx) : TheDef(D), Index(Idx) {}
33 
34   /// The name of the enumerated constant identifying this feature.
35   std::string getEnumName() const {
36     return "Feature_" + TheDef->getName().str();
37   }
38 
39   /// The name of the enumerated constant identifying the bitnumber for
40   /// this feature.
41   std::string getEnumBitName() const {
42     return "Feature_" + TheDef->getName().str() + "Bit";
43   }
44 
45   bool mustRecomputePerFunction() const {
46     return TheDef->getValueAsBit("RecomputePerFunction");
47   }
48 
49   void dump() const;
50   static std::vector<std::pair<Record *, SubtargetFeatureInfo>>
51   getAll(const RecordKeeper &Records);
52 
53   /// Emit the subtarget feature flag definitions.
54   ///
55   /// This version emits the bit index for the feature and can therefore support
56   /// more than 64 feature bits.
57   static void
58   emitSubtargetFeatureBitEnumeration(SubtargetFeatureInfoMap &SubtargetFeatures,
59                                      raw_ostream &OS);
60 
61   static void emitNameTable(SubtargetFeatureInfoMap &SubtargetFeatures,
62                             raw_ostream &OS);
63 
64   /// Emit the function to compute the list of available features given a
65   /// subtarget.
66   ///
67   /// This version is used for subtarget features defined using Predicate<>
68   /// and supports more than 64 feature bits.
69   ///
70   /// \param TargetName The name of the target as used in class prefixes (e.g.
71   ///                   <TargetName>Subtarget)
72   /// \param ClassName  The name of the class that will contain the generated
73   ///                   functions (including the target prefix.)
74   /// \param FuncName   The name of the function to emit.
75   /// \param SubtargetFeatures A map of TableGen records to the
76   ///                          SubtargetFeatureInfo equivalent.
77   /// \param ExtraParams Additional arguments to the generated function.
78   static void
79   emitComputeAvailableFeatures(StringRef TargetName, StringRef ClassName,
80                                StringRef FuncName,
81                                SubtargetFeatureInfoMap &SubtargetFeatures,
82                                raw_ostream &OS, StringRef ExtraParams = "");
83 
84   /// Emit the function to compute the list of available features given a
85   /// subtarget.
86   ///
87   /// This version is used for subtarget features defined using
88   /// AssemblerPredicate<> and supports up to 64 feature bits.
89   ///
90   /// \param TargetName The name of the target as used in class prefixes (e.g.
91   ///                   <TargetName>Subtarget)
92   /// \param ClassName  The name of the class (without the <Target> prefix)
93   ///                   that will contain the generated functions.
94   /// \param FuncName   The name of the function to emit.
95   /// \param SubtargetFeatures A map of TableGen records to the
96   ///                          SubtargetFeatureInfo equivalent.
97   static void emitComputeAssemblerAvailableFeatures(
98       StringRef TargetName, StringRef ClassName, StringRef FuncName,
99       SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS);
100 };
101 } // end namespace llvm
102 
103 #endif // LLVM_UTIL_TABLEGEN_SUBTARGETFEATUREINFO_H
104