Two more fixes to loop convert.
Summary: Ensure that the alias has the same type than the loop variable. Now it works with lambda captures.
Reviewers: klimek
Subscribers: alexfh, cfe-commits
Differential Revision: http://reviews.llvm.org/D12597
llvm-svn: 246762
diff --git a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
index f2e0f55..a690ecd 100644
--- a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
@@ -334,7 +334,8 @@
/// // use t, do not use i
/// }
/// \endcode
-static bool isAliasDecl(const Decl *TheDecl, const VarDecl *IndexVar) {
+static bool isAliasDecl(ASTContext *Context, const Decl *TheDecl,
+ const VarDecl *IndexVar) {
const auto *VDecl = dyn_cast<VarDecl>(TheDecl);
if (!VDecl)
return false;
@@ -346,6 +347,15 @@
if (!Init)
return false;
+ // Check that the declared type is the same as (or a reference to) the
+ // container type.
+ QualType DeclarationType = VDecl->getType();
+ if (DeclarationType->isReferenceType())
+ DeclarationType = DeclarationType.getNonReferenceType();
+ QualType InitType = Init->getType();
+ if (!Context->hasSameUnqualifiedType(DeclarationType, InitType))
+ return false;
+
switch (Init->getStmtClass()) {
case Stmt::ArraySubscriptExprClass: {
const auto *E = cast<ArraySubscriptExpr>(Init);
@@ -711,13 +721,49 @@
return true;
}
+/// \brief If the loop index is captured by a lambda, replace this capture
+/// by the range-for loop variable.
+///
+/// For example:
+/// \code
+/// for (int i = 0; i < N; ++i) {
+/// auto f = [v, i](int k) {
+/// printf("%d\n", v[i] + k);
+/// };
+/// f(v[i]);
+/// }
+/// \endcode
+///
+/// Will be replaced by:
+/// \code
+/// for (auto & elem : v) {
+/// auto f = [v, elem](int k) {
+/// printf("%d\n", elem + k);
+/// };
+/// f(elem);
+/// }
+/// \endcode
+bool ForLoopIndexUseVisitor::TraverseLambdaCapture(LambdaExpr *LE,
+ const LambdaCapture *C) {
+ if (C->capturesVariable()) {
+ const VarDecl* VDecl = C->getCapturedVar();
+ if (areSameVariable(IndexVar, cast<ValueDecl>(VDecl))) {
+ // FIXME: if the index is captured, it will count as an usage and the
+ // alias (if any) won't work, because it is only used in case of having
+ // exactly one usage.
+ Usages.push_back(Usage(nullptr, false, C->getLocation()));
+ }
+ }
+ return VisitorBase::TraverseLambdaCapture(LE, C);
+}
+
/// \brief If we find that another variable is created just to refer to the loop
/// element, note it for reuse as the loop variable.
///
/// See the comments for isAliasDecl.
bool ForLoopIndexUseVisitor::VisitDeclStmt(DeclStmt *S) {
if (!AliasDecl && S->isSingleDecl() &&
- isAliasDecl(S->getSingleDecl(), IndexVar)) {
+ isAliasDecl(Context, S->getSingleDecl(), IndexVar)) {
AliasDecl = S;
if (CurrStmtParent) {
if (isa<IfStmt>(CurrStmtParent) || isa<WhileStmt>(CurrStmtParent) ||
diff --git a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.h b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.h
index ec29b67..8a789fa 100644
--- a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.h
+++ b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.h
@@ -309,6 +309,7 @@
bool TraverseArraySubscriptExpr(ArraySubscriptExpr *E);
bool TraverseCXXMemberCallExpr(CXXMemberCallExpr *MemberCall);
bool TraverseCXXOperatorCallExpr(CXXOperatorCallExpr *OpCall);
+ bool TraverseLambdaCapture(LambdaExpr *LE, const LambdaCapture *C);
bool TraverseMemberExpr(MemberExpr *Member);
bool TraverseUnaryDeref(UnaryOperator *Uop);
bool VisitDeclRefExpr(DeclRefExpr *E);