From a5bb2f61cfb8a707cf20b61bc13bf3f3d60c50f5 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Fri, 23 May 2014 19:16:56 +0000 Subject: Use alias linkage and visibility to decide tls access mode. This matches both what we do for the non-thread case and what gcc does. With this patch clang would match gcc's behaviour in static __thread int a = 42; extern __thread int b __attribute__((alias("a"))); int *f(void) { return &a; } int *g(void) { return &b; } if not for pr19843. Manually writing the IL does produce the same access modes. It is also a step in the direction of fixing pr19844. llvm-svn: 209543 --- llvm/lib/Target/TargetMachine.cpp | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) (limited to 'llvm/lib/Target/TargetMachine.cpp') diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp index dbd433d5240..8365f64dc54 100644 --- a/llvm/lib/Target/TargetMachine.cpp +++ b/llvm/lib/Target/TargetMachine.cpp @@ -106,19 +106,13 @@ static TLSModel::Model getSelectedTLSModel(const GlobalVariable *Var) { } TLSModel::Model TargetMachine::getTLSModel(const GlobalValue *GV) const { - // If GV is an alias then use the aliasee for determining - // thread-localness. - if (const GlobalAlias *GA = dyn_cast(GV)) - GV = GA->getAliasee(); - const GlobalVariable *Var = cast(GV); - - bool isLocal = Var->hasLocalLinkage(); - bool isDeclaration = Var->isDeclaration(); + bool isLocal = GV->hasLocalLinkage(); + bool isDeclaration = GV->isDeclaration(); bool isPIC = getRelocationModel() == Reloc::PIC_; bool isPIE = Options.PositionIndependentExecutable; // FIXME: what should we do for protected and internal visibility? // For variables, is internal different from hidden? - bool isHidden = Var->hasHiddenVisibility(); + bool isHidden = GV->hasHiddenVisibility(); TLSModel::Model Model; if (isPIC && !isPIE) { @@ -133,10 +127,13 @@ TLSModel::Model TargetMachine::getTLSModel(const GlobalValue *GV) const { Model = TLSModel::InitialExec; } - // If the user specified a more specific model, use that. - TLSModel::Model SelectedModel = getSelectedTLSModel(Var); - if (SelectedModel > Model) - return SelectedModel; + const GlobalVariable *Var = dyn_cast(GV); + if (Var) { + // If the user specified a more specific model, use that. + TLSModel::Model SelectedModel = getSelectedTLSModel(Var); + if (SelectedModel > Model) + return SelectedModel; + } return Model; } -- cgit v1.2.3