1 files changed, 77 insertions, 0 deletions
diff --git a/clang-tools-extra/clang-tidy/performance/NoexceptMoveConstructorCheck.cpp b/clang-tools-extra/clang-tidy/performance/NoexceptMoveConstructorCheck.cpp
new file mode 100644
index 00000000000..86ef70ce094
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/performance/NoexceptMoveConstructorCheck.cpp
@@ -0,0 +1,77 @@
+//===--- NoexceptMoveConstructorCheck.cpp - clang-tidy---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "NoexceptMoveConstructorCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace performance {
+
+void NoexceptMoveConstructorCheck::registerMatchers(MatchFinder *Finder) {
+  // Only register the matchers for C++11; the functionality currently does not
+  // provide any benefit to other languages, despite being benign.
+  if (!getLangOpts().CPlusPlus11)
+    return;
+
+  Finder->addMatcher(
+      cxxMethodDecl(anyOf(cxxConstructorDecl(), hasOverloadedOperatorName("=")),
+                    unless(isImplicit()), unless(isDeleted()))
+          .bind("decl"),
+      this);
+}
+
+void NoexceptMoveConstructorCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  if (const auto *Decl = Result.Nodes.getNodeAs<CXXMethodDecl>("decl")) {
+    StringRef MethodType = "assignment operator";
+    if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(Decl)) {
+      if (!Ctor->isMoveConstructor())
+        return;
+      MethodType = "constructor";
+    } else if (!Decl->isMoveAssignmentOperator()) {
+      return;
+    }
+
+    const auto *ProtoType = Decl->getType()->getAs<FunctionProtoType>();
+
+    if (isUnresolvedExceptionSpec(ProtoType->getExceptionSpecType()))
+      return;
+
+    switch (ProtoType->getNoexceptSpec(*Result.Context)) {
+    case FunctionProtoType::NR_NoNoexcept:
+      diag(Decl->getLocation(), "move %0s should be marked noexcept")
+          << MethodType;
+      // FIXME: Add a fixit.
+      break;
+    case FunctionProtoType::NR_Throw:
+      // Don't complain about nothrow(false), but complain on nothrow(expr)
+      // where expr evaluates to false.
+      if (const Expr *E = ProtoType->getNoexceptExpr()) {
+        if (isa<CXXBoolLiteralExpr>(E))
+          break;
+        diag(E->getExprLoc(),
+             "noexcept specifier on the move %0 evaluates to 'false'")
+            << MethodType;
+      }
+      break;
+    case FunctionProtoType::NR_Nothrow:
+    case FunctionProtoType::NR_Dependent:
+    case FunctionProtoType::NR_BadNoexcept:
+      break;
+    }
+  }
+}
+
+} // namespace performance
+} // namespace tidy
+} // namespace clang