NFC Simplify AttributedStmt handling in clang CFG

Author: steakhal

clang/lib/Analysis/CFG.cpp

@@ -457,34 +457,16 @@ reverse_children::reverse_children(Stmt *S) {
       return;
     }
     case Stmt::AttributedStmtClass: {
-      AttributedStmt *attrStmt = cast<AttributedStmt>(S);
-      assert(attrStmt);
+      auto Attrs = cast<AttributedStmt>(S)->getAttrs();
 
-      {
-        // for an attributed stmt, the "children()" returns only the NullStmt
-        // (;) but semantically the "children" are supposed to be the
-        // expressions _within_ i.e. the two square brackets i.e. [[ HERE ]]
-        // so we add the subexpressions first, _then_ add the "children"
-
-        for (const Attr *attr : attrStmt->getAttrs()) {
-
-          // i.e. one `assume()`
-          CXXAssumeAttr const *assumeAttr = llvm::dyn_cast<CXXAssumeAttr>(attr);
-          if (!assumeAttr) {
-            continue;
-          }
-          // Only handles [[ assume(<assumption>) ]] right now
-          Expr *assumption = assumeAttr->getAssumption();
-          childrenBuf.push_back(assumption);
-        }
-
-        // children() for an AttributedStmt is NullStmt(;)
-        llvm::append_range(childrenBuf, attrStmt->children());
-
-        // This needs to be done *after* childrenBuf has been populated.
+      // We only handle `[[assume(...)]]` attributes for now.
+      if (const auto *A = getSpecificAttr<CXXAssumeAttr>(Attrs)) {
+        childrenBuf.push_back(A->getAssumption());
+        llvm::append_range(childrenBuf, S->children());
         children = childrenBuf;
+        return;
       }
-      return;
+      break;
     }
     default:
       break;