[RISCV][NFC] Rename RequiredExtensions to RequiredFeatures.

[jacquesguan]

Summary

The field 'RequiredExtensions' is used to specify the constraint for rvv builtin, and it contains something which is not a sub-extension or extension such as 'RV64'. So the word 'extension' is not accurate now, 'feature' seems better.

[asb]

Makes sense to me, but I'll defer to someone else working more actively with this part of the codebase for a final LGTM.

[khchen]

LGTM

clang/include/clang/Basic/riscv_vector.td

class RVVBuiltin<string suffix, string prototype, string type_range,
 
   // If HasMask, this is the ID of the LLVM intrinsic we want to lower to.
   string IRNameMask = NAME #"_mask";
 
   // If non empty, this is the code emitted in the header, otherwise
   // an automatic definition in header is emitted.
   string HeaderCode = "";
 
-  // Sub extension of vector spec.
-  list<string> RequiredExtensions = [];
+  // Features required to enable for this builtin.
+  list<string> RequiredFeatures = [];
 
   // Number of fields for Load/Store Segment instructions.
   int NF = 1;
 }
 
 class RVVHeader
 {
   code HeaderCode;
let ManualCodegen = [{
               if !not(IsFloat<type>.val) then {
                 def: RVVBuiltin<"Uv", "UvPCUe" # eew_type # "Uv", type>;
               }
           }
         }
         defvar eew64 = "64";
         defvar eew64_type = "(Log2EEW:6)";
         let Name = op # eew64 # "_v", IRName = op, IRNameMask = op # "_mask",
-            RequiredExtensions = ["RV64"] in {
+            RequiredFeatures = ["RV64"] in {
             def: RVVBuiltin<"v", "vPCe" # eew64_type # "Uv", type>;
               if !not(IsFloat<type>.val) then {
                 def: RVVBuiltin<"Uv", "UvPCUe" # eew64_type # "Uv", type>;
               }
           }
       }
   }
 }
let HasMaskedOffOperand = false,
             if !not(IsFloat<type>.val) then {
               def : RVVBuiltin<"Uv", "0PUe" # eew_type # "UvUv", type>;
             }
           }
         }
         defvar eew64 = "64";
         defvar eew64_type = "(Log2EEW:6)";
         let Name = op # eew64  # "_v", IRName = op, IRNameMask = op # "_mask",
-            RequiredExtensions = ["RV64"]  in  {
+            RequiredFeatures = ["RV64"]  in  {
           def : RVVBuiltin<"v", "0Pe" # eew64_type # "Uvv", type>;
           if !not(IsFloat<type>.val) then {
             def : RVVBuiltin<"Uv", "0PUe" # eew64_type # "UvUv", type>;
           }
         }
       }
   }
 }

clang/utils/TableGen/RISCVVEmitter.cpp

 
 public:
   RVVIntrinsic(StringRef Name, StringRef Suffix, StringRef MangledName,
                StringRef MangledSuffix, StringRef IRName, bool IsMask,
                bool HasMaskedOffOperand, bool HasVL, bool HasPolicy,
                bool HasNoMaskedOverloaded, bool HasAutoDef,
                StringRef ManualCodegen, const RVVTypes &Types,
                const std::vector<int64_t> &IntrinsicTypes,
-               const std::vector<StringRef> &RequiredExtensions, unsigned NF);
+               const std::vector<StringRef> &RequiredFeatures, unsigned NF);
   ~RVVIntrinsic() = default;
 
   StringRef getBuiltinName() const { return BuiltinName; }
   StringRef getName() const { return Name; }
   StringRef getMangledName() const { return MangledName; }
   bool hasVL() const { return HasVL; }
   bool hasPolicy() const { return HasPolicy; }
   bool hasNoMaskedOverloaded() const { return HasNoMaskedOverloaded; }

 //===----------------------------------------------------------------------===//
 RVVIntrinsic::RVVIntrinsic(StringRef NewName, StringRef Suffix,
                            StringRef NewMangledName, StringRef MangledSuffix,
                            StringRef IRName, bool IsMask,
                            bool HasMaskedOffOperand, bool HasVL, bool HasPolicy,
                            bool HasNoMaskedOverloaded, bool HasAutoDef,
                            StringRef ManualCodegen, const RVVTypes &OutInTypes,
                            const std::vector<int64_t> &NewIntrinsicTypes,
-                           const std::vector<StringRef> &RequiredExtensions,
+                           const std::vector<StringRef> &RequiredFeatures,
                            unsigned NF)
     : IRName(IRName), IsMask(IsMask), HasVL(HasVL), HasPolicy(HasPolicy),
       HasNoMaskedOverloaded(HasNoMaskedOverloaded), HasAutoDef(HasAutoDef),
       ManualCodegen(ManualCodegen.str()), NF(NF) {
 
   // Init BuiltinName, Name and MangledName
   BuiltinName = NewName.str();
   Name = BuiltinName;
if (T->isFloatVector(16) || T->isFloat(16))
       RISCVPredefinedMacros |= RISCVPredefinedMacro::Zfh;
     if (T->isFloatVector(32))
       RISCVPredefinedMacros |= RISCVPredefinedMacro::VectorMaxELenFp32;
     if (T->isFloatVector(64))
       RISCVPredefinedMacros |= RISCVPredefinedMacro::VectorMaxELenFp64;
     if (T->isVector(64))
       RISCVPredefinedMacros |= RISCVPredefinedMacro::VectorMaxELen64;
   }
-  for (auto Extension : RequiredExtensions) {
-    if (Extension == "RV64")
+  for (auto Feature : RequiredFeatures) {
+    if (Feature == "RV64")
       RISCVPredefinedMacros |= RISCVPredefinedMacro::RV64;
   }
 
   // Init OutputType and InputTypes
   OutputType = OutInTypes[0];
   InputTypes.assign(OutInTypes.begin() + 1, OutInTypes.end());
 
   // IntrinsicTypes is nonmasked version index. Need to update it
for (auto *R : RV) {
     bool HasVL = R->getValueAsBit("HasVL");
     bool HasPolicy = R->getValueAsBit("HasPolicy");
     bool HasNoMaskedOverloaded = R->getValueAsBit("HasNoMaskedOverloaded");
     std::vector<int64_t> Log2LMULList = R->getValueAsListOfInts("Log2LMUL");
     StringRef ManualCodegen = R->getValueAsString("ManualCodegen");
     StringRef ManualCodegenMask = R->getValueAsString("ManualCodegenMask");
     std::vector<int64_t> IntrinsicTypes =
         R->getValueAsListOfInts("IntrinsicTypes");
-    std::vector<StringRef> RequiredExtensions =
-        R->getValueAsListOfStrings("RequiredExtensions");
+    std::vector<StringRef> RequiredFeatures =
+        R->getValueAsListOfStrings("RequiredFeatures");
     StringRef IRName = R->getValueAsString("IRName");
     StringRef IRNameMask = R->getValueAsString("IRNameMask");
     unsigned NF = R->getValueAsInt("NF");
 
     StringRef HeaderCodeStr = R->getValueAsString("HeaderCode");
     bool HasAutoDef = HeaderCodeStr.empty();
     if (!HeaderCodeStr.empty()) {
       HeaderCode += HeaderCodeStr.str();
for (char I : TypeRange) {
 
         auto SuffixStr = getSuffixStr(I, Log2LMUL, SuffixProto);
         auto MangledSuffixStr = getSuffixStr(I, Log2LMUL, MangledSuffixProto);
         // Create a non-mask intrinsic
         Out.push_back(std::make_unique<RVVIntrinsic>(
             Name, SuffixStr, MangledName, MangledSuffixStr, IRName,
             /*IsMask=*/false, /*HasMaskedOffOperand=*/false, HasVL, HasPolicy,
             HasNoMaskedOverloaded, HasAutoDef, ManualCodegen, Types.getValue(),
-            IntrinsicTypes, RequiredExtensions, NF));
+            IntrinsicTypes, RequiredFeatures, NF));
         if (HasMask) {
           // Create a mask intrinsic
           Optional<RVVTypes> MaskTypes =
               computeTypes(I, Log2LMUL, NF, ProtoMaskSeq);
           Out.push_back(std::make_unique<RVVIntrinsic>(
               Name, SuffixStr, MangledName, MangledSuffixStr, IRNameMask,
               /*IsMask=*/true, HasMaskedOffOperand, HasVL, HasPolicy,
               HasNoMaskedOverloaded, HasAutoDef, ManualCodegenMask,
-              MaskTypes.getValue(), IntrinsicTypes, RequiredExtensions, NF));
+              MaskTypes.getValue(), IntrinsicTypes, RequiredFeatures, NF));
         }
       } // end for Log2LMULList
     }   // end for TypeRange
   }
 }
 
 void RVVEmitter::createRVVHeaders(raw_ostream &OS) {
   std::vector<Record *> RVVHeaders =