[cfe-commits] r91218 - in /cfe/trunk: include/clang/AST/ExprCXX.h lib/Sema/SemaTemplateInstantiateDecl.cpp lib/Sema/TreeTransform.h test/SemaTemplate/instantiate-expr-4.cpp
Douglas Gregor
dgregor at apple.com
Sat Dec 12 10:16:41 PST 2009
Author: dgregor
Date: Sat Dec 12 12:16:41 2009
New Revision: 91218
URL: http://llvm.org/viewvc/llvm-project?rev=91218&view=rev
Log:
Rework the way we handle template instantiation for
implicitly-generated AST nodes. We previously built instantiated nodes
for each of these AST nodes, then passed them on to Sema, which was
not prepared to see already-type-checked nodes (see PR5755). In some
places, we had ugly workarounds to try to avoid re-type-checking
(e.g., in VarDecl initializer instantiation).
Now, we skip implicitly-generated nodes when performing instantiation,
preferring instead to build just the AST nodes that directly reflect
what was written in the source code. This has several advantages:
- We don't need to instantiate anything that doesn't have a direct
correlation to the source code, so we can have better location
information.
- Semantic analysis sees the same thing at template instantiation
time that it would see for a non-template.
- At least one ugly hack (VarDecl initializers) goes away.
Fixes PR5755.
Modified:
cfe/trunk/include/clang/AST/ExprCXX.h
cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
cfe/trunk/lib/Sema/TreeTransform.h
cfe/trunk/test/SemaTemplate/instantiate-expr-4.cpp
Modified: cfe/trunk/include/clang/AST/ExprCXX.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/ExprCXX.h?rev=91218&r1=91217&r2=91218&view=diff
==============================================================================
--- cfe/trunk/include/clang/AST/ExprCXX.h (original)
+++ cfe/trunk/include/clang/AST/ExprCXX.h Sat Dec 12 12:16:41 2009
@@ -527,6 +527,7 @@
const_arg_iterator arg_begin() const { return Args; }
const_arg_iterator arg_end() const { return Args + NumArgs; }
+ Expr **getArgs() const { return reinterpret_cast<Expr **>(Args); }
unsigned getNumArgs() const { return NumArgs; }
/// getArg - Return the specified argument.
Modified: cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp?rev=91218&r1=91217&r2=91218&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp Sat Dec 12 12:16:41 2009
@@ -16,6 +16,7 @@
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/DeclVisitor.h"
#include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
#include "clang/Basic/PrettyStackTrace.h"
#include "clang/Lex/Preprocessor.h"
@@ -204,16 +205,6 @@
= SemaRef.SubstExpr(D->getInit(), TemplateArgs);
if (Init.isInvalid())
Var->setInvalidDecl();
- else if (!D->getType()->isDependentType() &&
- !D->getInit()->isTypeDependent() &&
- !D->getInit()->isValueDependent()) {
- // If neither the declaration's type nor its initializer are dependent,
- // we don't want to redo all the checking, especially since the
- // initializer might have been wrapped by a CXXConstructExpr since we did
- // it the first time.
- Var->setType(D->getType());
- Var->setInit(SemaRef.Context, Init.takeAs<Expr>());
- }
else if (ParenListExpr *PLE = dyn_cast<ParenListExpr>((Expr *)Init.get())) {
// FIXME: We're faking all of the comma locations, which is suboptimal.
// Do we even need these comma locations?
@@ -239,7 +230,47 @@
// When Init is destroyed, it will destroy the instantiated ParenListExpr;
// we've explicitly retained all of its subexpressions already.
- } else
+ } else if (CXXConstructExpr *Construct
+ = dyn_cast<CXXConstructExpr>((Expr *)Init.get())) {
+ // We build CXXConstructExpr nodes to capture the implicit
+ // construction of objects. Rip apart the CXXConstructExpr to
+ // pass its pieces down to the appropriate initialization
+ // function.
+ if (D->hasCXXDirectInitializer()) {
+ // FIXME: Poor source location information
+ SourceLocation FakeLParenLoc =
+ SemaRef.PP.getLocForEndOfToken(D->getLocation());
+ SourceLocation FakeRParenLoc = FakeLParenLoc;
+ llvm::SmallVector<SourceLocation, 4> FakeCommaLocs;
+ if (Construct->getNumArgs() > 0) {
+ FakeRParenLoc
+ = SemaRef.PP.getLocForEndOfToken(
+ Construct->getArg(Construct->getNumArgs() - 1)->getLocEnd());
+
+ FakeCommaLocs.reserve(Construct->getNumArgs() - 1);
+ for (unsigned I = 0, N = Construct->getNumArgs() - 1; I != N; ++I) {
+ Expr *E = Construct->getArg(I)->Retain();
+ FakeCommaLocs.push_back(
+ SemaRef.PP.getLocForEndOfToken(E->getLocEnd()));
+ }
+ Construct->getArg(Construct->getNumArgs() - 1)->Retain();
+ }
+
+ SemaRef.AddCXXDirectInitializerToDecl(Sema::DeclPtrTy::make(Var),
+ FakeLParenLoc,
+ Sema::MultiExprArg(SemaRef,
+ (void **)Construct->getArgs(),
+ Construct->getNumArgs()),
+ FakeCommaLocs.data(),
+ FakeRParenLoc);
+
+ } else if (Construct->getNumArgs() >= 1) {
+ SemaRef.AddInitializerToDecl(Sema::DeclPtrTy::make(Var),
+ SemaRef.Owned(Construct->getArg(0)->Retain()),
+ false);
+ } else
+ SemaRef.ActOnUninitializedDecl(Sema::DeclPtrTy::make(Var), false);
+ } else
SemaRef.AddInitializerToDecl(Sema::DeclPtrTy::make(Var), move(Init),
D->hasCXXDirectInitializer());
SemaRef.PopExpressionEvaluationContext();
Modified: cfe/trunk/lib/Sema/TreeTransform.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/TreeTransform.h?rev=91218&r1=91217&r2=91218&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/TreeTransform.h (original)
+++ cfe/trunk/lib/Sema/TreeTransform.h Sat Dec 12 12:16:41 2009
@@ -993,19 +993,6 @@
move(LHS), move(RHS));
}
- /// \brief Build a new implicit cast expression.
- ///
- /// By default, builds a new implicit cast without any semantic analysis.
- /// Subclasses may override this routine to provide different behavior.
- OwningExprResult RebuildImplicitCastExpr(QualType T, CastExpr::CastKind Kind,
- ExprArg SubExpr, bool isLvalue) {
- ImplicitCastExpr *ICE
- = new (getSema().Context) ImplicitCastExpr(T, Kind,
- (Expr *)SubExpr.release(),
- isLvalue);
- return getSema().Owned(ICE);
- }
-
/// \brief Build a new C-style cast expression.
///
/// By default, performs semantic analysis to build the new expression.
@@ -3779,29 +3766,39 @@
move(RHS));
}
+/// \brief Given a cast expression, extract the subexpression of the
+/// cast, looking through intermediate AST nodes that were generated
+/// as part of type checking.
+static Expr *getCastSubExprAsWritten(CastExpr *E) {
+ Expr *SubExpr = 0;
+ do {
+ SubExpr = E->getSubExpr();
+
+ // Temporaries will be re-bound when rebuilding the original cast
+ // expression.
+ if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
+ SubExpr = Binder->getSubExpr();
+
+ // Conversions by constructor and conversion functions have a
+ // subexpression describing the call; strip it off.
+ if (E->getCastKind() == CastExpr::CK_ConstructorConversion)
+ SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0);
+ else if (E->getCastKind() == CastExpr::CK_UserDefinedConversion)
+ SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument();
+
+ // If the subexpression we're left with is an implicit cast, look
+ // through that, too.
+ } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr)));
+
+ return SubExpr;
+}
+
template<typename Derived>
Sema::OwningExprResult
TreeTransform<Derived>::TransformImplicitCastExpr(ImplicitCastExpr *E) {
- TemporaryBase Rebase(*this, E->getLocStart(), DeclarationName());
-
- // FIXME: Will we ever have type information here? It seems like we won't,
- // so do we even need to transform the type?
- QualType T = getDerived().TransformType(E->getType());
- if (T.isNull())
- return SemaRef.ExprError();
-
- OwningExprResult SubExpr = getDerived().TransformExpr(E->getSubExpr());
- if (SubExpr.isInvalid())
- return SemaRef.ExprError();
-
- if (!getDerived().AlwaysRebuild() &&
- T == E->getType() &&
- SubExpr.get() == E->getSubExpr())
- return SemaRef.Owned(E->Retain());
-
- return getDerived().RebuildImplicitCastExpr(T, E->getCastKind(),
- move(SubExpr),
- E->isLvalueCast());
+ // Implicit casts are eliminated during transformation, since they
+ // will be recomputed by semantic analysis after transformation.
+ return getDerived().TransformExpr(getCastSubExprAsWritten(E));
}
template<typename Derived>
@@ -3826,7 +3823,8 @@
return SemaRef.ExprError();
}
- OwningExprResult SubExpr = getDerived().TransformExpr(E->getSubExpr());
+ OwningExprResult SubExpr
+ = getDerived().TransformExpr(getCastSubExprAsWritten(E));
if (SubExpr.isInvalid())
return SemaRef.ExprError();
@@ -4182,7 +4180,8 @@
return SemaRef.ExprError();
}
- OwningExprResult SubExpr = getDerived().TransformExpr(E->getSubExpr());
+ OwningExprResult SubExpr
+ = getDerived().TransformExpr(getCastSubExprAsWritten(E));
if (SubExpr.isInvalid())
return SemaRef.ExprError();
@@ -4246,7 +4245,8 @@
return SemaRef.ExprError();
}
- OwningExprResult SubExpr = getDerived().TransformExpr(E->getSubExpr());
+ OwningExprResult SubExpr
+ = getDerived().TransformExpr(getCastSubExprAsWritten(E));
if (SubExpr.isInvalid())
return SemaRef.ExprError();
Modified: cfe/trunk/test/SemaTemplate/instantiate-expr-4.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaTemplate/instantiate-expr-4.cpp?rev=91218&r1=91217&r2=91218&view=diff
==============================================================================
--- cfe/trunk/test/SemaTemplate/instantiate-expr-4.cpp (original)
+++ cfe/trunk/test/SemaTemplate/instantiate-expr-4.cpp Sat Dec 12 12:16:41 2009
@@ -96,6 +96,18 @@
template struct Delete0<X*>;
template struct Delete0<int>; // expected-note{{instantiation}}
+namespace PR5755 {
+ template <class T>
+ void Foo() {
+ char* p = 0;
+ delete[] p;
+ }
+
+ void Test() {
+ Foo<int>();
+ }
+}
+
// ---------------------------------------------------------------------
// throw expressions
// ---------------------------------------------------------------------
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