Refactor to share code for handling return statements between lambda expressions and block literals. As it turns out, almost all the logic can be shared.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149031 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 8a53ece..018aadf 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -8769,6 +8769,8 @@
else
CurContext = Block;
+ getCurBlock()->HasImplicitReturnType = true;
+
// Enter a new evaluation context to insulate the block from any
// cleanups from the enclosing full-expression.
PushExpressionEvaluationContext(PotentiallyEvaluated);
@@ -8835,6 +8837,7 @@
if (RetTy != Context.DependentTy) {
CurBlock->ReturnType = RetTy;
CurBlock->TheDecl->setBlockMissingReturnType(false);
+ CurBlock->HasImplicitReturnType = false;
}
// Push block parameters from the declarator if we had them.
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index fdcad08..f847e2e 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -1781,53 +1781,51 @@
return Res;
}
-/// ActOnBlockReturnStmt - Utility routine to figure out block's return type.
+/// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
+/// for capturing scopes.
///
StmtResult
-Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
- // If this is the first return we've seen in the block, infer the type of
- // the block from it.
- BlockScopeInfo *CurBlock = getCurBlock();
- if (CurBlock->TheDecl->blockMissingReturnType()) {
- QualType BlockReturnT;
+Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
+ // If this is the first return we've seen, infer the return type.
+ // [expr.prim.lambda]p4 in C++11; block literals follow a superset of those
+ // rules which allows multiple return statements.
+ CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
+ if (CurCap->HasImplicitReturnType) {
+ QualType ReturnT;
if (RetValExp) {
- // Don't call UsualUnaryConversions(), since we don't want to do
- // integer promotions here.
ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
if (Result.isInvalid())
return StmtError();
RetValExp = Result.take();
- if (!RetValExp->isTypeDependent()) {
- BlockReturnT = RetValExp->getType();
- if (BlockDeclRefExpr *CDRE = dyn_cast<BlockDeclRefExpr>(RetValExp)) {
- // We have to remove a 'const' added to copied-in variable which was
- // part of the implementation spec. and not the actual qualifier for
- // the variable.
- if (CDRE->isConstQualAdded())
- CurBlock->ReturnType.removeLocalConst(); // FIXME: local???
- }
- } else
- BlockReturnT = Context.DependentTy;
- } else
- BlockReturnT = Context.VoidTy;
- if (!CurBlock->ReturnType.isNull() && !CurBlock->ReturnType->isDependentType()
- && !BlockReturnT->isDependentType()
- // when block's return type is not specified, all return types
- // must strictly match.
- && !Context.hasSameType(BlockReturnT, CurBlock->ReturnType)) {
- Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
- << BlockReturnT << CurBlock->ReturnType;
- return StmtError();
+ if (!RetValExp->isTypeDependent())
+ ReturnT = RetValExp->getType();
+ else
+ ReturnT = Context.DependentTy;
+ } else {
+ ReturnT = Context.VoidTy;
}
- CurBlock->ReturnType = BlockReturnT;
+ // We require the return types to strictly match here.
+ if (!CurCap->ReturnType.isNull() &&
+ !CurCap->ReturnType->isDependentType() &&
+ !ReturnT->isDependentType() &&
+ !Context.hasSameType(ReturnT, CurCap->ReturnType)) {
+ // FIXME: Adapt diagnostic for lambdas.
+ Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
+ << ReturnT << CurCap->ReturnType;
+ return StmtError();
+ }
+ CurCap->ReturnType = ReturnT;
}
- QualType FnRetType = CurBlock->ReturnType;
+ QualType FnRetType = CurCap->ReturnType;
+ assert(!FnRetType.isNull());
- if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
- Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
- return StmtError();
- }
+ if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap))
+ if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
+ Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
+ return StmtError();
+ }
+ // FIXME: [[noreturn]] for lambdas!
// Otherwise, verify that this result type matches the previous one. We are
// pickier with blocks than for normal functions because we don't have GCC
@@ -1891,8 +1889,8 @@
if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
return StmtError();
- if (getCurBlock())
- return ActOnBlockReturnStmt(ReturnLoc, RetValExp);
+ if (isa<CapturingScopeInfo>(getCurFunction()))
+ return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
QualType FnRetType;
QualType DeclaredRetType;
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 2404451..284371b 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -8142,30 +8142,20 @@
}
const FunctionType *exprFunctionType = E->getFunctionType();
- QualType exprResultType = exprFunctionType->getResultType();
- if (!exprResultType.isNull()) {
- if (!exprResultType->isDependentType())
- blockScope->ReturnType = exprResultType;
- else if (exprResultType != getSema().Context.DependentTy)
- blockScope->ReturnType = getDerived().TransformType(exprResultType);
- }
-
- // If the return type has not been determined yet, leave it as a dependent
- // type; it'll get set when we process the body.
- if (blockScope->ReturnType.isNull())
- blockScope->ReturnType = getSema().Context.DependentTy;
+ QualType exprResultType =
+ getDerived().TransformType(exprFunctionType->getResultType());
// Don't allow returning a objc interface by value.
- if (blockScope->ReturnType->isObjCObjectType()) {
+ if (exprResultType->isObjCObjectType()) {
getSema().Diag(E->getCaretLocation(),
diag::err_object_cannot_be_passed_returned_by_value)
- << 0 << blockScope->ReturnType;
+ << 0 << exprResultType;
getSema().ActOnBlockError(E->getCaretLocation(), /*Scope=*/0);
return ExprError();
}
QualType functionType = getDerived().RebuildFunctionProtoType(
- blockScope->ReturnType,
+ exprResultType,
paramTypes.data(),
paramTypes.size(),
oldBlock->isVariadic(),
@@ -8176,12 +8166,11 @@
// Set the parameters on the block decl.
if (!params.empty())
blockScope->TheDecl->setParams(params);
-
- // If the return type wasn't explicitly set, it will have been marked as a
- // dependent type (DependentTy); clear out the return type setting so
- // we will deduce the return type when type-checking the block's body.
- if (blockScope->ReturnType == getSema().Context.DependentTy)
- blockScope->ReturnType = QualType();
+
+ if (!oldBlock->blockMissingReturnType()) {
+ blockScope->HasImplicitReturnType = false;
+ blockScope->ReturnType = exprResultType;
+ }
// Transform the body
StmtResult body = getDerived().TransformStmt(E->getBody());