[clang] Extract function for generated part of clang::hasAttribute (NFC)

[wanders]

Summary

This makes it easier to add additional handling when the
tablegen-generated code does not find a match.

No functional change intended.

[erichkeane]

clang/lib/Basic/Attributes.cpp

39–41

Why is this not just return hasAttributeImpl(...)?

[erichkeane]

I see now having seen the other review, LGTM.

clang/lib/Basic/Attributes.cpp

 #include "clang/Basic/Attributes.h"
 #include "clang/Basic/AttrSubjectMatchRules.h"
 #include "clang/Basic/AttributeCommonInfo.h"
 #include "clang/Basic/IdentifierTable.h"
 using namespace clang;
 
+static int hasAttributeImpl(AttributeCommonInfo::Syntax Syntax, StringRef Name,
+                            StringRef ScopeName, const TargetInfo &Target,
+                            const LangOptions &LangOpts) {
+
+#include "clang/Basic/AttrHasAttributeImpl.inc"
+
+  return 0;
+}
+
 int clang::hasAttribute(AttributeCommonInfo::Syntax Syntax,
                         const IdentifierInfo *Scope, const IdentifierInfo *Attr,
                         const TargetInfo &Target, const LangOptions &LangOpts) {
   StringRef Name = Attr->getName();
   // Normalize the attribute name, __foo__ becomes foo.
   if (Name.size() >= 4 && Name.startswith("__") && Name.endswith("__"))
     Name = Name.substr(2, Name.size() - 4);
 
   // Normalize the scope name, but only for gnu and clang attributes.
   StringRef ScopeName = Scope ? Scope->getName() : "";
   if (ScopeName == "__gnu__")
     ScopeName = "gnu";
   else if (ScopeName == "_Clang")
     ScopeName = "clang";
 
   // As a special case, look for the omp::sequence and omp::directive
   // attributes. We support those, but not through the typical attribute
   // machinery that goes through TableGen. We support this in all OpenMP modes
   // so long as double square brackets are enabled.
   if (LangOpts.OpenMP && LangOpts.DoubleSquareBracketAttributes &&
       ScopeName == "omp")
     return (Name == "directive" || Name == "sequence") ? 1 : 0;
 
-#include "clang/Basic/AttrHasAttributeImpl.inc"
+  int res = hasAttributeImpl(Syntax, Name, ScopeName, Target, LangOpts);
+  if (res)
+    return res;
 
   return 0;
 }
 
 const char *attr::getSubjectMatchRuleSpelling(attr::SubjectMatchRule Rule) {
   switch (Rule) {
 #define ATTR_MATCH_RULE(NAME, SPELLING, IsAbstract)                            \
   case attr::NAME:                                                             \