From ede4a8aa2be346d4f175e61cf4a18a023ea3198d Mon Sep 17 00:00:00 2001 From: Chandler Carruth Date: Sun, 8 Apr 2012 17:51:45 +0000 Subject: Teach LLVM about a PIE option which, when enabled on top of PIC, makes optimizations which are valid for position independent code being linked into a single executable, but not for such code being linked into a shared library. I discussed the design of this with Eric Christopher, and the decision was to support an optional bit rather than a completely separate relocation model. Fundamentally, this is still PIC relocation, its just that certain optimizations are only valid under a PIC relocation model when the resulting code won't be in a shared library. The simplest path to here is to expose a single bit option in the TargetOptions. If folks have different/better designs, I'm all ears. =] I've included the first optimization based upon this: changing TLS models to the *Exec models when PIE is enabled. This is the LLVM component of PR12380 and is all of the hard work. llvm-svn: 154294 --- llvm/lib/Target/TargetMachine.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Target/TargetMachine.cpp') diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp index b8e7f15d092..b9b2526876f 100644 --- a/llvm/lib/Target/TargetMachine.cpp +++ b/llvm/lib/Target/TargetMachine.cpp @@ -82,7 +82,8 @@ TLSModel::Model TargetMachine::getTLSModel(const GlobalValue *GV) const { // For variables, is internal different from hidden? bool isHidden = GV->hasHiddenVisibility(); - if (getRelocationModel() == Reloc::PIC_) { + if (getRelocationModel() == Reloc::PIC_ && + !Options.PositionIndependentExecutable) { if (isLocal || isHidden) return TLSModel::LocalDynamic; else -- cgit v1.2.3