[NFC][RISCV] Bundle up ISAInfo updates and checks

[eopXD]

Update code. Try to encapsulate more.

[eopXD]

Rebase again, the test failure in past diff seems to be caused by other commits.

[eopXD]

Rebase.

[kito-cheng]

LGTM

llvm/include/llvm/Support/RISCVISAInfo.h

void addExtension(StringRef ExtName, unsigned MajorVersion,
                     unsigned MinorVersion);
 
   Error checkDependency();
 
   void updateImplication();
   void updateFLen();
   void updateMinVLen();
   void updateMaxELen();
+
+  static llvm::Expected<std::unique_ptr<RISCVISAInfo>>
+  postProcessAndChecking(std::unique_ptr<RISCVISAInfo> &&ISAInfo);
 };
 
 } // namespace llvm
 
 #endif

llvm/lib/Support/RISCVISAInfo.cpp

for (auto &Feature : Features) {
 
     if (Add)
       ISAInfo->addExtension(ExtName, ExtensionInfoIterator->Version.Major,
                             ExtensionInfoIterator->Version.Minor);
     else
       ISAInfo->Exts.erase(ExtName.str());
   }
 
-  ISAInfo->updateImplication();
-  ISAInfo->updateFLen();
-  ISAInfo->updateMinVLen();
-  ISAInfo->updateMaxELen();
-
-  if (Error Result = ISAInfo->checkDependency())
-    return std::move(Result);
-
-  return std::move(ISAInfo);
+  return RISCVISAInfo::postProcessAndChecking(std::move(ISAInfo));
 }
 
 llvm::Expected<std::unique_ptr<RISCVISAInfo>>
 RISCVISAInfo::parseArchString(StringRef Arch, bool EnableExperimentalExtension,
                               bool ExperimentalExtensionVersionCheck) {
   // RISC-V ISA strings must be lowercase.
   if (llvm::any_of(Arch, isupper)) {
     return createStringError(errc::invalid_argument,
RISCVISAInfo::parseArchString(StringRef Arch, bool EnableExperimentalExtension,
   for (auto Ext : AllExts) {
     if (!isSupportedExtension(Ext)) {
       StringRef Desc = getExtensionTypeDesc(getExtensionType(Ext));
       return createStringError(errc::invalid_argument, "unsupported %s '%s'",
                                Desc.str().c_str(), Ext.str().c_str());
     }
   }
 
-  ISAInfo->updateImplication();
-  ISAInfo->updateFLen();
-  ISAInfo->updateMinVLen();
-  ISAInfo->updateMaxELen();
-
-  if (Error Result = ISAInfo->checkDependency())
-    return std::move(Result);
-
-  return std::move(ISAInfo);
+  return RISCVISAInfo::postProcessAndChecking(std::move(ISAInfo));
 }
 
 Error RISCVISAInfo::checkDependency() {
   bool IsRv32 = XLen == 32;
   bool HasE = Exts.count("e") != 0;
   bool HasD = Exts.count("d") != 0;
   bool HasF = Exts.count("f") != 0;
   bool HasZve32x = Exts.count("zve32x") != 0;
if (ExtName == "i") // i is not recognized in clang -cc1
       continue;
     std::string Feature = isExperimentalExtension(ExtName)
                               ? "+experimental-" + ExtName
                               : "+" + ExtName;
     FeatureVector.push_back(Feature);
   }
   return FeatureVector;
 }
+
+llvm::Expected<std::unique_ptr<RISCVISAInfo>>
+RISCVISAInfo::postProcessAndChecking(std::unique_ptr<RISCVISAInfo> &&ISAInfo) {
+  ISAInfo->updateImplication();
+  ISAInfo->updateFLen();
+  ISAInfo->updateMinVLen();
+  ISAInfo->updateMaxELen();
+
+  if (Error Result = ISAInfo->checkDependency())
+    return std::move(Result);
+  return std::move(ISAInfo);
+}