[cfe-commits] r111086 - in /cfe/trunk: include/clang/Sema/Sema.h lib/AST/ASTContext.cpp lib/Sema/Sema.cpp lib/Sema/SemaDecl.cpp lib/Sema/SemaTemplate.cpp lib/Sema/SemaTemplateInstantiateDecl.cpp test/Sema/warn-unused-function.c test/SemaCXX/warn-unused-filescoped.cpp
Argyrios Kyrtzidis
akyrtzi at gmail.com
Sat Aug 14 18:15:20 PDT 2010
Author: akirtzidis
Date: Sat Aug 14 20:15:20 2010
New Revision: 111086
URL: http://llvm.org/viewvc/llvm-project?rev=111086&view=rev
Log:
Commit improved version of 111026 & 111027.
Unused warnings for functions:
-static functions
-functions in anonymous namespace
-class methods in anonymous namespace
-class method specializations in anonymous namespace
-function specializations in anonymous namespace
Unused warnings for variables:
-static variables
-variables in anonymous namespace
-static data members in anonymous namespace
-static data members specializations in anonymous namespace
Reveals lots of opportunities for dead code removal in llvm codebase that will
interest my esteemed colleagues.
Added:
cfe/trunk/test/SemaCXX/warn-unused-filescoped.cpp
Modified:
cfe/trunk/include/clang/Sema/Sema.h
cfe/trunk/lib/AST/ASTContext.cpp
cfe/trunk/lib/Sema/Sema.cpp
cfe/trunk/lib/Sema/SemaDecl.cpp
cfe/trunk/lib/Sema/SemaTemplate.cpp
cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
cfe/trunk/test/Sema/warn-unused-function.c
Modified: cfe/trunk/include/clang/Sema/Sema.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Sema.h?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/include/clang/Sema/Sema.h (original)
+++ cfe/trunk/include/clang/Sema/Sema.h Sat Aug 14 20:15:20 2010
@@ -349,7 +349,7 @@
std::vector<VarDecl *> TentativeDefinitions;
/// \brief The set of file scoped decls seen so far that have not been used
- /// and must warn if not used.
+ /// and must warn if not used. Only contains the first declaration.
std::vector<const DeclaratorDecl*> UnusedFileScopedDecls;
class AccessedEntity {
@@ -1877,6 +1877,10 @@
MultiStmtArg Handlers);
void DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock);
+ bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const;
+
+ /// \brief If it's a file scoped decl that must warn if not used, keep track
+ /// of it.
void MarkUnusedFileScopedDecl(const DeclaratorDecl *D);
/// DiagnoseUnusedExprResult - If the statement passed in is an expression
Modified: cfe/trunk/lib/AST/ASTContext.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ASTContext.cpp?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ASTContext.cpp (original)
+++ cfe/trunk/lib/AST/ASTContext.cpp Sat Aug 14 20:15:20 2010
@@ -5640,7 +5640,8 @@
// FIXME: Handle references.
if (const RecordType *RT = VD->getType()->getAs<RecordType>()) {
if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
- if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor())
+ if (RD->hasDefinition() &&
+ (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()))
return true;
}
}
Modified: cfe/trunk/lib/Sema/Sema.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/Sema.cpp?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/Sema.cpp (original)
+++ cfe/trunk/lib/Sema/Sema.cpp Sat Aug 14 20:15:20 2010
@@ -235,6 +235,42 @@
void Sema::DeleteStmt(StmtTy *S) {
}
+/// \brief Used to prune the decls of Sema's UnusedFileScopedDecls vector.
+static bool ShouldRemoveFromUnused(Sema *SemaRef, const DeclaratorDecl *D) {
+ if (D->isUsed())
+ return true;
+
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+ // UnusedFileScopedDecls stores the first declaration.
+ // The declaration may have become definition so check again.
+ const FunctionDecl *DeclToCheck;
+ if (FD->hasBody(DeclToCheck))
+ return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck);
+
+ // Later redecls may add new information resulting in not having to warn,
+ // so check again.
+ DeclToCheck = FD->getMostRecentDeclaration();
+ if (DeclToCheck != FD)
+ return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck);
+ }
+
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ // UnusedFileScopedDecls stores the first declaration.
+ // The declaration may have become definition so check again.
+ const VarDecl *DeclToCheck = VD->getDefinition();
+ if (DeclToCheck)
+ return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck);
+
+ // Later redecls may add new information resulting in not having to warn,
+ // so check again.
+ DeclToCheck = VD->getMostRecentDeclaration();
+ if (DeclToCheck != VD)
+ return !SemaRef->ShouldWarnIfUnusedFileScopedDecl(DeclToCheck);
+ }
+
+ return false;
+}
+
/// ActOnEndOfTranslationUnit - This is called at the very end of the
/// translation unit when EOF is reached and all but the top-level scope is
/// popped.
@@ -263,10 +299,10 @@
}
// Remove file scoped decls that turned out to be used.
- UnusedFileScopedDecls.erase(std::remove_if(UnusedFileScopedDecls.begin(),
- UnusedFileScopedDecls.end(),
- std::bind2nd(std::mem_fun(&DeclaratorDecl::isUsed),
- true)),
+ UnusedFileScopedDecls.erase(std::remove_if(UnusedFileScopedDecls.begin(),
+ UnusedFileScopedDecls.end(),
+ std::bind1st(std::ptr_fun(ShouldRemoveFromUnused),
+ this)),
UnusedFileScopedDecls.end());
if (!CompleteTranslationUnit) {
@@ -336,11 +372,19 @@
for (std::vector<const DeclaratorDecl*>::iterator
I = UnusedFileScopedDecls.begin(),
E = UnusedFileScopedDecls.end(); I != E; ++I) {
- if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I))
- Diag(FD->getLocation(), diag::warn_unused_function) << FD->getDeclName();
- else
- Diag((*I)->getLocation(), diag::warn_unused_variable)
- << cast<VarDecl>(*I)->getDeclName();
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) {
+ const FunctionDecl *DiagD;
+ if (!FD->hasBody(DiagD))
+ DiagD = FD;
+ Diag(DiagD->getLocation(), diag::warn_unused_function)
+ << DiagD->getDeclName();
+ } else {
+ const VarDecl *DiagD = cast<VarDecl>(*I)->getDefinition();
+ if (!DiagD)
+ DiagD = cast<VarDecl>(*I);
+ Diag(DiagD->getLocation(), diag::warn_unused_variable)
+ << DiagD->getDeclName();
+ }
}
TUScope = 0;
Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Sat Aug 14 20:15:20 2010
@@ -521,25 +521,71 @@
F.done();
}
-static bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) {
+bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
+ assert(D);
+
+ if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
+ return false;
+
+ // Ignore class templates.
+ if (D->getDeclContext()->isDependentContext())
+ return false;
+
+ // We warn for unused decls internal to the translation unit.
+ if (D->getLinkage() == ExternalLinkage)
+ return false;
+
+ if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+ if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
+ return false;
+
+ if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+ if (MD->isVirtual())
+ return false;
+ } else {
+ // 'static inline' functions are used in headers; don't warn.
+ if (FD->getStorageClass() == FunctionDecl::Static &&
+ FD->isInlineSpecified())
+ return false;
+ }
+
+ if (FD->isThisDeclarationADefinition())
+ return !Context.DeclMustBeEmitted(FD);
+ return true;
+ }
+
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ if (VD->isStaticDataMember() &&
+ VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
+ return false;
+
+ if ( VD->isFileVarDecl() &&
+ !VD->getType().isConstant(Context))
+ return !Context.DeclMustBeEmitted(VD);
+ }
+
+ return false;
+ }
+
+ void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
+ if (!D)
+ return;
+
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
- // Warn for static, non-inlined function definitions that
- // have not been used.
- // FIXME: Also include static functions declared but not defined.
- return (!FD->isInvalidDecl()
- && !FD->isInlined() && FD->getLinkage() == InternalLinkage
- && !FD->isUsed() && !FD->hasAttr<UnusedAttr>()
- && !FD->hasAttr<ConstructorAttr>()
- && !FD->hasAttr<DestructorAttr>());
+ const FunctionDecl *First = FD->getFirstDeclaration();
+ if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
+ return; // First should already be in the vector.
}
-
- return false;
-}
-void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
- if (ShouldWarnIfUnusedFileScopedDecl(D))
- UnusedFileScopedDecls.push_back(D);
-}
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ const VarDecl *First = VD->getFirstDeclaration();
+ if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
+ return; // First should already be in the vector.
+ }
+
+ if (ShouldWarnIfUnusedFileScopedDecl(D))
+ UnusedFileScopedDecls.push_back(D);
+ }
static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
if (D->isInvalidDecl())
@@ -2743,6 +2789,8 @@
if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord())
AddPushedVisibilityAttribute(NewVD);
+ MarkUnusedFileScopedDecl(NewVD);
+
return NewVD;
}
@@ -3638,8 +3686,7 @@
if (FunctionTemplate)
return FunctionTemplate;
- if (IsFunctionDefinition)
- MarkUnusedFileScopedDecl(NewFD);
+ MarkUnusedFileScopedDecl(NewFD);
return NewFD;
}
Modified: cfe/trunk/lib/Sema/SemaTemplate.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplate.cpp?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplate.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplate.cpp Sat Aug 14 20:15:20 2010
@@ -4360,8 +4360,10 @@
// Mark the prior declaration as an explicit specialization, so that later
// clients know that this is an explicit specialization.
- if (!isFriend)
+ if (!isFriend) {
SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization);
+ MarkUnusedFileScopedDecl(Specialization);
+ }
// Turn the given function declaration into a function template
// specialization, with the template arguments from the previous
@@ -4514,6 +4516,7 @@
cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction(
cast<CXXMethodDecl>(InstantiatedFrom),
TSK_ExplicitSpecialization);
+ MarkUnusedFileScopedDecl(InstantiationFunction);
} else if (isa<VarDecl>(Member)) {
VarDecl *InstantiationVar = cast<VarDecl>(Instantiation);
if (InstantiationVar->getTemplateSpecializationKind() ==
@@ -4526,6 +4529,7 @@
Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member),
cast<VarDecl>(InstantiatedFrom),
TSK_ExplicitSpecialization);
+ MarkUnusedFileScopedDecl(InstantiationVar);
} else {
assert(isa<CXXRecordDecl>(Member) && "Only member classes remain");
CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation);
Modified: cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaTemplateInstantiateDecl.cpp Sat Aug 14 20:15:20 2010
@@ -449,7 +449,7 @@
// Diagnose unused local variables.
if (!Var->isInvalidDecl() && Owner->isFunctionOrMethod() && !Var->isUsed())
SemaRef.DiagnoseUnusedDecl(Var);
-
+
return Var;
}
@@ -1415,7 +1415,7 @@
else
Owner->addDecl(DeclToAdd);
}
-
+
return Method;
}
Modified: cfe/trunk/test/Sema/warn-unused-function.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/warn-unused-function.c?rev=111086&r1=111085&r2=111086&view=diff
==============================================================================
--- cfe/trunk/test/Sema/warn-unused-function.c (original)
+++ cfe/trunk/test/Sema/warn-unused-function.c Sat Aug 14 20:15:20 2010
@@ -35,3 +35,12 @@
__attribute__((destructor)) static void bar3(void);
void bar3(void) { }
+
+static void f10(void); // expected-warning{{unused}}
+static void f10(void);
+
+static void f11(void);
+static void f11(void) { } // expected-warning{{unused}}
+
+static void f12(void) { } // expected-warning{{unused}}
+static void f12(void);
Added: cfe/trunk/test/SemaCXX/warn-unused-filescoped.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-unused-filescoped.cpp?rev=111086&view=auto
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-unused-filescoped.cpp (added)
+++ cfe/trunk/test/SemaCXX/warn-unused-filescoped.cpp Sat Aug 14 20:15:20 2010
@@ -0,0 +1,54 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -Wunused %s
+
+static void f1(); // expected-warning{{unused}}
+
+namespace {
+ void f2(); // expected-warning{{unused}}
+
+ void f3() { } // expected-warning{{unused}}
+
+ struct S {
+ void m1() { } // expected-warning{{unused}}
+ void m2(); // expected-warning{{unused}}
+ void m3();
+ };
+
+ template <typename T>
+ struct TS {
+ void m();
+ };
+ template <> void TS<int>::m() { } // expected-warning{{unused}}
+
+ template <typename T>
+ void tf() { }
+ template <> void tf<int>() { } // expected-warning{{unused}}
+
+ struct VS {
+ virtual void vm() { }
+ };
+
+ struct SVS : public VS {
+ void vm() { }
+ };
+}
+
+void S::m3() { } // expected-warning{{unused}}
+
+static inline void f4() { }
+const unsigned int cx = 0;
+
+static int x1; // expected-warning{{unused}}
+
+namespace {
+ int x2; // expected-warning{{unused}}
+
+ struct S2 {
+ static int x; // expected-warning{{unused}}
+ };
+
+ template <typename T>
+ struct TS2 {
+ static int x;
+ };
+ template <> int TS2<int>::x; // expected-warning{{unused}}
+}
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