From 61e1f5cc721b67ea42d962024ebd0d323f7a7f93 Mon Sep 17 00:00:00 2001
From: Hans Wennborg <hans@hanshq.net>
Date: Thu, 15 May 2014 22:07:49 +0000
Subject: [PATCH] Allow dllimport/dllexport on inline functions and adjust the
linkage.
This is a step towards handling these attributes on classes (PR11170).
Differential Revision: http://reviews.llvm.org/D3772
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@208925 91177308-0d34-0410-b5e6-96231b3b80d8
---
include/clang/Basic/DiagnosticSemaKinds.td | 2 ++
lib/AST/ASTContext.cpp | 38 +++++++++++++++++++---
lib/AST/Decl.cpp | 2 +-
lib/CodeGen/CodeGenModule.cpp | 15 ++-------
lib/Sema/SemaDecl.cpp | 20 ++++--------
lib/Sema/SemaDeclAttr.cpp | 15 ---------
test/CodeGen/dllexport.c | 8 +++++
test/CodeGenCXX/dllexport.cpp | 25 ++++++++++++++
test/CodeGenCXX/dllimport.cpp | 25 ++++++++++++++
test/Sema/dllexport.c | 4 +--
test/Sema/dllimport.c | 6 ++--
test/SemaCXX/MicrosoftExtensions.cpp | 2 +-
test/SemaCXX/dllexport.cpp | 10 +++---
test/SemaCXX/dllimport.cpp | 14 ++++----
14 files changed, 121 insertions(+), 65 deletions(-)
create mode 100644 test/CodeGen/dllexport.c
create mode 100644 test/CodeGenCXX/dllexport.cpp
create mode 100644 test/CodeGenCXX/dllimport.cpp
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 5d5e3849edc..4e434a4063b 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2091,6 +2091,8 @@ def warn_attribute_invalid_on_definition : Warning<
InGroup<IgnoredAttributes>;
def err_attribute_dll_redeclaration : Error<
"redeclaration of %q0 cannot add %q1 attribute">;
+def err_attribute_dllimport_function_definition : Error<
+ "dllimport cannot be applied to non-inline function definition">;
def err_attribute_dllimport_data_definition : Error<
"definition of dllimport data">;
def err_attribute_weakref_not_static : Error<
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index aa74e1a6924..2f406166690 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -7742,7 +7742,8 @@ QualType ASTContext::GetBuiltinType(unsigned Id,
return getFunctionType(ResType, ArgTypes, EPI);
}
-GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
+static GVALinkage basicGVALinkageForFunction(const ASTContext &Context,
+ const FunctionDecl *FD) {
if (!FD->isExternallyVisible())
return GVA_Internal;
@@ -7773,8 +7774,11 @@ GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
if (!FD->isInlined())
return External;
- if ((!getLangOpts().CPlusPlus && !getLangOpts().MSVCCompat) ||
+ if ((!Context.getLangOpts().CPlusPlus && !Context.getLangOpts().MSVCCompat &&
+ !FD->hasAttr<DLLExportAttr>()) ||
FD->hasAttr<GNUInlineAttr>()) {
+ // FIXME: This doesn't match gcc's behavior for dllexport inline functions.
+
// GNU or C99 inline semantics. Determine whether this symbol should be
// externally visible.
if (FD->isInlineDefinitionExternallyVisible())
@@ -7793,7 +7797,26 @@ GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
return GVA_DiscardableODR;
}
-GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
+static GVALinkage adjustGVALinkageForDLLAttribute(GVALinkage L, const Decl *D) {
+ // See http://msdn.microsoft.com/en-us/library/xa0d9ste.aspx
+ // dllexport/dllimport on inline functions.
+ if (D->hasAttr<DLLImportAttr>()) {
+ if (L == GVA_DiscardableODR || L == GVA_StrongODR)
+ return GVA_AvailableExternally;
+ } else if (D->hasAttr<DLLExportAttr>()) {
+ if (L == GVA_DiscardableODR)
+ return GVA_StrongODR;
+ }
+ return L;
+}
+
+GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) const {
+ return adjustGVALinkageForDLLAttribute(basicGVALinkageForFunction(*this, FD),
+ FD);
+}
+
+static GVALinkage basicGVALinkageForVariable(const ASTContext &Context,
+ const VarDecl *VD) {
if (!VD->isExternallyVisible())
return GVA_Internal;
@@ -7807,7 +7830,7 @@ GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
// enclosing function.
if (LexicalContext)
StaticLocalLinkage =
- GetGVALinkageForFunction(cast<FunctionDecl>(LexicalContext));
+ Context.GetGVALinkageForFunction(cast<FunctionDecl>(LexicalContext));
// GVA_StrongODR function linkage is stronger than what we need,
// downgrade to GVA_DiscardableODR.
@@ -7821,7 +7844,7 @@ GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
// Itanium-specified entry point, which has the normal linkage of the
// variable.
if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
- getTargetInfo().getTriple().isMacOSX())
+ Context.getTargetInfo().getTriple().isMacOSX())
return GVA_Internal;
switch (VD->getTemplateSpecializationKind()) {
@@ -7842,6 +7865,11 @@ GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
llvm_unreachable("Invalid Linkage!");
}
+GVALinkage ASTContext::GetGVALinkageForVariable(const VarDecl *VD) {
+ return adjustGVALinkageForDLLAttribute(basicGVALinkageForVariable(*this, VD),
+ VD);
+}
+
bool ASTContext::DeclMustBeEmitted(const Decl *D) {
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
if (!VD->isFileVarDecl())
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 49466b2d98b..101b1646248 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -2572,7 +2572,7 @@ bool FunctionDecl::isMSExternInline() const {
assert(isInlined() && "expected to get called on an inlined function!");
const ASTContext &Context = getASTContext();
- if (!Context.getLangOpts().MSVCCompat)
+ if (!Context.getLangOpts().MSVCCompat && !hasAttr<DLLExportAttr>())
return false;
for (const FunctionDecl *FD = this; FD; FD = FD->getPreviousDecl())
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 25399cc1958..d9d2eb0fb56 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -1960,15 +1960,6 @@ llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
if (Linkage == GVA_AvailableExternally)
return llvm::Function::AvailableExternallyLinkage;
- // LinkOnceODRLinkage is insufficient if the symbol is required to exist in
- // the symbol table. Promote the linkage to WeakODRLinkage to preserve the
- // semantics of LinkOnceODRLinkage while providing visibility in the symbol
- // table.
- llvm::GlobalValue::LinkageTypes OnceLinkage =
- llvm::GlobalValue::LinkOnceODRLinkage;
- if (D->hasAttr<DLLExportAttr>() || D->hasAttr<DLLImportAttr>())
- OnceLinkage = llvm::GlobalVariable::WeakODRLinkage;
-
// Note that Apple's kernel linker doesn't support symbol
// coalescing, so we need to avoid linkonce and weak linkages there.
// Normally, this means we just map to internal, but for explicit
@@ -1981,7 +1972,7 @@ llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
// merged with other definitions. c) C++ has the ODR, so we know the
// definition is dependable.
if (Linkage == GVA_DiscardableODR)
- return !Context.getLangOpts().AppleKext ? OnceLinkage
+ return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage
: llvm::Function::InternalLinkage;
// An explicit instantiation of a template has weak linkage, since
@@ -1995,14 +1986,14 @@ llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
// Destructor variants in the Microsoft C++ ABI are always linkonce_odr thunks
// emitted on an as-needed basis.
if (UseThunkForDtorVariant)
- return OnceLinkage;
+ return llvm::GlobalValue::LinkOnceODRLinkage;
// If required by the ABI, give definitions of static data members with inline
// initializers at least linkonce_odr linkage.
if (getCXXABI().isInlineInitializedStaticDataMemberLinkOnce() &&
isa<VarDecl>(D) &&
isVarDeclInlineInitializedStaticDataMember(cast<VarDecl>(D)))
- return OnceLinkage;
+ return llvm::GlobalValue::LinkOnceODRLinkage;
// C++ doesn't have tentative definitions and thus cannot have common
// linkage.
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 2f434cedfe6..3c19e9632f6 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -9764,20 +9764,12 @@ Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) {
if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
ResolveExceptionSpec(D->getLocation(), FPT);
- // Checking attributes of current function definition
- // dllimport attribute.
- DLLImportAttr *DA = FD->getAttr<DLLImportAttr>();
- if (DA && (!FD->hasAttr<DLLExportAttr>())) {
- // dllimport attribute cannot be directly applied to definition.
- // Microsoft accepts dllimport for functions defined within class scope.
- if (!DA->isInherited() &&
- !(LangOpts.MicrosoftExt && FD->getLexicalDeclContext()->isRecord())) {
- Diag(FD->getLocation(),
- diag::err_attribute_can_be_applied_only_to_symbol_declaration)
- << DA;
- FD->setInvalidDecl();
- return D;
- }
+ // dllimport cannot be applied to non-inline function definitions.
+ if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined()) {
+ assert(!FD->hasAttr<DLLExportAttr>());
+ Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
+ FD->setInvalidDecl();
+ return D;
}
// We want to attach documentation to original Decl (which might be
// a function template).
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 5ca5a8fc26a..9caf9189b9b 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -3841,13 +3841,6 @@ static void handleDLLImportAttr(Sema &S, Decl *D, const AttributeList &Attr) {
return;
}
- // Currently, the dllimport attribute is ignored for inlined functions.
- // Warning is emitted.
- if (FD && FD->isInlineSpecified()) {
- S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
- return;
- }
-
unsigned Index = Attr.getAttributeSpellingListIndex();
DLLImportAttr *NewAttr = S.mergeDLLImportAttr(D, Attr.getRange(), Index);
if (NewAttr)
@@ -3868,14 +3861,6 @@ DLLExportAttr *Sema::mergeDLLExportAttr(Decl *D, SourceRange Range,
}
static void handleDLLExportAttr(Sema &S, Decl *D, const AttributeList &Attr) {
- // Currently, the dllexport attribute is ignored for inlined functions, unless
- // the -fkeep-inline-functions flag has been used. Warning is emitted.
- if (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isInlineSpecified()) {
- // FIXME: ... unless the -fkeep-inline-functions flag has been used.
- S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
- return;
- }
-
unsigned Index = Attr.getAttributeSpellingListIndex();
DLLExportAttr *NewAttr = S.mergeDLLExportAttr(D, Attr.getRange(), Index);
if (NewAttr)
diff --git a/test/CodeGen/dllexport.c b/test/CodeGen/dllexport.c
new file mode 100644
index 00000000000..ce5636c1727
--- /dev/null
+++ b/test/CodeGen/dllexport.c
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -triple i686-pc-win32 -std=c99 -O2 -disable-llvm-optzns -emit-llvm < %s | FileCheck %s
+
+#define DLLEXPORT __declspec(dllexport)
+
+inline void DLLEXPORT f() {}
+extern void DLLEXPORT f();
+
+// CHECK: define weak_odr dllexport void @f()
diff --git a/test/CodeGenCXX/dllexport.cpp b/test/CodeGenCXX/dllexport.cpp
new file mode 100644
index 00000000000..fe9806893b2
--- /dev/null
+++ b/test/CodeGenCXX/dllexport.cpp
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -triple i686-pc-win32 -x c++ -O2 -disable-llvm-optzns -emit-llvm < %s | FileCheck %s
+
+#define DLLEXPORT __declspec(dllexport)
+
+void DLLEXPORT a();
+// CHECK-DAG: declare dllexport void @"\01?a@@YAXXZ"()
+
+inline void DLLEXPORT b() {}
+// CHECK-DAG: define weak_odr dllexport void @"\01?b@@YAXXZ"()
+
+template <typename T> void c() {}
+template void DLLEXPORT c<int>();
+// CHECK-DAG: define weak_odr dllexport void @"\01??$c@H@@YAXXZ"()
+
+struct S {
+ void DLLEXPORT a() {}
+ // CHECK-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?a@S@@QAEXXZ"
+};
+
+void user() {
+ // FIXME: dllexported functions must be emitted even if they're not referenced in this TU.
+ a();
+ b();
+ &S::a;
+}
diff --git a/test/CodeGenCXX/dllimport.cpp b/test/CodeGenCXX/dllimport.cpp
new file mode 100644
index 00000000000..d8e58f71903
--- /dev/null
+++ b/test/CodeGenCXX/dllimport.cpp
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -triple i686-pc-win32 -x c++ -O2 -disable-llvm-optzns -emit-llvm < %s | FileCheck %s
+
+#define DLLIMPORT __declspec(dllimport)
+
+void DLLIMPORT a();
+// CHECK-DAG: declare dllimport void @"\01?a@@YAXXZ"()
+
+inline void DLLIMPORT b() {}
+// CHECK-DAG: define available_externally dllimport void @"\01?b@@YAXXZ"()
+
+template <typename T> inline void c() {} // FIXME: MSVC accepts this without 'inline' too.
+template void DLLIMPORT c<int>();
+// CHECK-DAG: define available_externally dllimport void @"\01??$c@H@@YAXXZ"()
+
+struct S {
+ void DLLIMPORT a() {}
+ // CHECK-DAG: define available_externally dllimport x86_thiscallcc void @"\01?a@S@@QAEXXZ"
+};
+
+void user(S* s) {
+ a();
+ b();
+ c<int>();
+ s->a();
+}
diff --git a/test/Sema/dllexport.c b/test/Sema/dllexport.c
index 8a71e5d7251..3a80b0be158 100644
--- a/test/Sema/dllexport.c
+++ b/test/Sema/dllexport.c
@@ -69,10 +69,10 @@ void __declspec(dllexport) decl2B();
__declspec(dllexport) void def() {}
// Export inline function.
-__declspec(dllexport) inline void inlineFunc1() {} // expected-warning{{'dllexport' attribute ignored}}
+__declspec(dllexport) inline void inlineFunc1() {}
extern void inlineFunc1();
-inline void __attribute__((dllexport)) inlineFunc2() {} // expected-warning{{'dllexport' attribute ignored}}
+inline void __attribute__((dllexport)) inlineFunc2() {}
extern void inlineFunc2();
// Redeclarations
diff --git a/test/Sema/dllimport.c b/test/Sema/dllimport.c
index a4982940c65..fa3e2b385a4 100644
--- a/test/Sema/dllimport.c
+++ b/test/Sema/dllimport.c
@@ -97,11 +97,11 @@ void __attribute__((dllimport)) decl2A();
void __declspec(dllimport) decl2B();
// Not allowed on function definitions.
-__declspec(dllimport) void def() {} // expected-error{{'dllimport' attribute can be applied only to symbol declaration}}
+__declspec(dllimport) void def() {} // expected-error{{dllimport cannot be applied to non-inline function definition}}
// Import inline function.
-__declspec(dllimport) inline void inlineFunc1() {} // expected-warning{{'dllimport' attribute ignored}}
-inline void __attribute__((dllimport)) inlineFunc2() {} // expected-warning{{'dllimport' attribute ignored}}
+__declspec(dllimport) inline void inlineFunc1() {}
+inline void __attribute__((dllimport)) inlineFunc2() {}
// Redeclarations
__declspec(dllimport) void redecl1();
diff --git a/test/SemaCXX/MicrosoftExtensions.cpp b/test/SemaCXX/MicrosoftExtensions.cpp
index 0f6ebbb0699..3420d20cb8d 100644
--- a/test/SemaCXX/MicrosoftExtensions.cpp
+++ b/test/SemaCXX/MicrosoftExtensions.cpp
@@ -122,7 +122,7 @@ __declspec(dllimport) void f(void) { }
void f2(void); // expected-note{{previous declaration is here}}
};
-__declspec(dllimport) void AAA::f2(void) { // expected-error{{'dllimport' attribute can be applied only to symbol}}
+__declspec(dllimport) void AAA::f2(void) { // expected-error{{dllimport cannot be applied to non-inline function definition}}
// expected-error@-1{{redeclaration of 'AAA::f2' cannot add 'dllimport' attribute}}
}
diff --git a/test/SemaCXX/dllexport.cpp b/test/SemaCXX/dllexport.cpp
index 3558eef8b83..6d67ec25da3 100644
--- a/test/SemaCXX/dllexport.cpp
+++ b/test/SemaCXX/dllexport.cpp
@@ -92,10 +92,10 @@ __declspec(dllexport) void def() {}
extern "C" __declspec(dllexport) void externC() {}
// Export inline function.
-__declspec(dllexport) inline void inlineFunc1() {} // expected-warning{{'dllexport' attribute ignored}}
-inline void __attribute__((dllexport)) inlineFunc2() {} // expected-warning{{'dllexport' attribute ignored}}
+__declspec(dllexport) inline void inlineFunc1() {}
+inline void __attribute__((dllexport)) inlineFunc2() {}
-__declspec(dllexport) inline void inlineDecl(); // expected-warning{{'dllexport' attribute ignored}}
+__declspec(dllexport) inline void inlineDecl();
void inlineDecl() {}
__declspec(dllexport) void inlineDef();
@@ -188,7 +188,7 @@ template void exportedFuncTmpl<ExplicitInst_Exported>();
// Export specialization of an exported function template.
template<> __declspec(dllexport) void exportedFuncTmpl<ExplicitSpec_Exported>();
template<> __declspec(dllexport) void exportedFuncTmpl<ExplicitSpec_Def_Exported>() {}
-template<> __declspec(dllexport) inline void exportedFuncTmpl<ExplicitSpec_InlineDef_Exported>() {} // expected-warning{{'dllexport' attribute ignored}}
+template<> __declspec(dllexport) inline void exportedFuncTmpl<ExplicitSpec_InlineDef_Exported>() {}
// Not exporting specialization of an exported function template without
// explicit dllexport.
@@ -205,7 +205,7 @@ template __declspec(dllexport) void funcTmpl<ExplicitInst_Exported>();
// Export specialization of a non-exported function template.
template<> __declspec(dllexport) void funcTmpl<ExplicitSpec_Exported>();
template<> __declspec(dllexport) void funcTmpl<ExplicitSpec_Def_Exported>() {}
-template<> __declspec(dllexport) inline void funcTmpl<ExplicitSpec_InlineDef_Exported>() {} // expected-warning{{'dllexport' attribute ignored}}
+template<> __declspec(dllexport) inline void funcTmpl<ExplicitSpec_InlineDef_Exported>() {}
diff --git a/test/SemaCXX/dllimport.cpp b/test/SemaCXX/dllimport.cpp
index 95e9e7d053f..def18fa18e8 100644
--- a/test/SemaCXX/dllimport.cpp
+++ b/test/SemaCXX/dllimport.cpp
@@ -116,14 +116,14 @@ void __attribute__((dllimport)) decl2A();
void __declspec(dllimport) decl2B();
// Not allowed on function definitions.
-__declspec(dllimport) void def() {} // expected-error{{'dllimport' attribute can be applied only to symbol declaration}}
+__declspec(dllimport) void def() {} // expected-error{{dllimport cannot be applied to non-inline function definition}}
// extern "C"
extern "C" __declspec(dllexport) void externC();
// Import inline function.
-__declspec(dllimport) inline void inlineFunc1() {} // expected-warning{{'dllimport' attribute ignored}}
-inline void __attribute__((dllimport)) inlineFunc2() {} // expected-warning{{'dllimport' attribute ignored}}
+__declspec(dllimport) inline void inlineFunc1() {}
+inline void __attribute__((dllimport)) inlineFunc2() {}
// Redeclarations
__declspec(dllimport) void redecl1();
@@ -209,8 +209,8 @@ template<typename T> __declspec(dllimport) void importedFuncTmpl();
// Import specialization of an imported function template. A definition must be
// declared inline.
template<> __declspec(dllimport) void importedFuncTmpl<ExplicitSpec_Imported>();
-template<> __declspec(dllimport) void importedFuncTmpl<ExplicitSpec_Def_Imported>() {} // expected-error{{'dllimport' attribute can be applied only to symbol declaration}}
-template<> __declspec(dllimport) inline void importedFuncTmpl<ExplicitSpec_InlineDef_Imported>() {} // expected-warning{{'dllimport' attribute ignored}}
+template<> __declspec(dllimport) void importedFuncTmpl<ExplicitSpec_Def_Imported>() {} // expected-error{{dllimport cannot be applied to non-inline function definition}}
+template<> __declspec(dllimport) inline void importedFuncTmpl<ExplicitSpec_InlineDef_Imported>() {}
// Not importing specialization of an imported function template without
// explicit dllimport.
@@ -223,5 +223,5 @@ extern template __declspec(dllimport) void funcTmpl<ExplicitDecl_Imported>();
// Import specialization of a non-imported function template. A definition must
// be declared inline.
template<> __declspec(dllimport) void funcTmpl<ExplicitSpec_Imported>();
-template<> __declspec(dllimport) void funcTmpl<ExplicitSpec_Def_Imported>() {} // expected-error{{'dllimport' attribute can be applied only to symbol declaration}}
-template<> __declspec(dllimport) inline void funcTmpl<ExplicitSpec_InlineDef_Imported>() {} // expected-warning{{'dllimport' attribute ignored}}
+template<> __declspec(dllimport) void funcTmpl<ExplicitSpec_Def_Imported>() {} // expected-error{{dllimport cannot be applied to non-inline function definition}}
+template<> __declspec(dllimport) inline void funcTmpl<ExplicitSpec_InlineDef_Imported>() {}
--
GitLab