Support the tls_model attribute (PR9788)
This adds support for the tls_model attribute. This allows the user to
choose a TLS model that is better than what LLVM would select by
default. For example, a variable might be declared as:
__thread int x __attribute__((tls_model("initial-exec")));
if it will not be used in a shared library that is dlopen'ed.
This depends on LLVM r159077.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159078 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index b443911..744d18b 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -43,7 +43,8 @@
ExpectedMethod,
ExpectedVariableFunctionOrLabel,
ExpectedFieldOrGlobalVar,
- ExpectedStruct
+ ExpectedStruct,
+ ExpectedTLSVar
};
//===----------------------------------------------------------------------===//
@@ -1440,6 +1441,42 @@
D->addAttr(::new (S.Context) AlwaysInlineAttr(Attr.getRange(), S.Context));
}
+static void handleTLSModelAttr(Sema &S, Decl *D,
+ const AttributeList &Attr) {
+ // Check the attribute arguments.
+ if (Attr.getNumArgs() != 1) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
+ return;
+ }
+
+ Expr *Arg = Attr.getArg(0);
+ Arg = Arg->IgnoreParenCasts();
+ StringLiteral *Str = dyn_cast<StringLiteral>(Arg);
+
+ // Check that it is a string.
+ if (!Str) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_not_string) << "tls_model";
+ return;
+ }
+
+ if (!isa<VarDecl>(D) || !cast<VarDecl>(D)->isThreadSpecified()) {
+ S.Diag(Attr.getLoc(), diag::err_attribute_wrong_decl_type)
+ << Attr.getName() << ExpectedTLSVar;
+ return;
+ }
+
+ // Check that the value.
+ StringRef Model = Str->getString();
+ if (Model != "global-dynamic" && Model != "local-dynamic"
+ && Model != "initial-exec" && Model != "local-exec") {
+ S.Diag(Attr.getLoc(), diag::err_attr_tlsmodel_arg);
+ return;
+ }
+
+ D->addAttr(::new (S.Context) TLSModelAttr(Attr.getRange(), S.Context,
+ Model));
+}
+
static void handleMallocAttr(Sema &S, Decl *D, const AttributeList &Attr) {
// Check the attribute arguments.
if (Attr.hasParameterOrArguments()) {
@@ -3939,6 +3976,7 @@
handleAlwaysInlineAttr (S, D, Attr); break;
case AttributeList::AT_AnalyzerNoReturn:
handleAnalyzerNoReturnAttr (S, D, Attr); break;
+ case AttributeList::AT_TLSModel: handleTLSModelAttr (S, D, Attr); break;
case AttributeList::AT_Annotate: handleAnnotateAttr (S, D, Attr); break;
case AttributeList::AT_Availability:handleAvailabilityAttr(S, D, Attr); break;
case AttributeList::AT_CarriesDependency: