Revert "[safestack] Fast access to the unsafe stack pointer on AArch64/Android."

[oota-llvm.git] / lib / CodeGen / TargetLoweringBase.cpp

diff --git a/lib/CodeGen/TargetLoweringBase.cpp b/lib/CodeGen/TargetLoweringBase.cpp
index 6de59b9333112c4162f90720e08e7a8738e2ed26..7250fdc9385a3064aa48d2b5c240e6ea3effe445 100644 (file)
--- a/lib/CodeGen/TargetLoweringBase.cpp
+++ b/lib/CodeGen/TargetLoweringBase.cpp
@@ -1662,40 +1662,6 @@ TargetLoweringBase::getTypeLegalizationCost(const DataLayout &DL,
   }
 }
 
-Value *TargetLoweringBase::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
-  Module *M = IRB.GetInsertBlock()->getParent()->getParent();
-  Type *StackPtrTy = Type::getInt8PtrTy(M->getContext());
-  if (TM.getTargetTriple().getEnvironment() == llvm::Triple::Android) {
-    // Android provides a libc function to retrieve the address of the current
-    // thread's unsafe stack pointer.
-    Value *Fn = M->getOrInsertFunction("__safestack_pointer_address",
-                                       StackPtrTy->getPointerTo(0), nullptr);
-    return IRB.CreateCall(Fn);
-  } else {
-    // Otherwise, assume the target links with compiler-rt, which provides a
-    // thread-local variable with a magic name.
-    const char *UnsafeStackPtrVar = "__safestack_unsafe_stack_ptr";
-    auto UnsafeStackPtr =
-        dyn_cast_or_null<GlobalVariable>(M->getNamedValue(UnsafeStackPtrVar));
-
-    if (!UnsafeStackPtr) {
-      // The global variable is not defined yet, define it ourselves.
-      // We use the initial-exec TLS model because we do not support the
-      // variable living anywhere other than in the main executable.
-      UnsafeStackPtr = new GlobalVariable(
-          *M, StackPtrTy, false, GlobalValue::ExternalLinkage, 0,
-          UnsafeStackPtrVar, nullptr, GlobalValue::InitialExecTLSModel);
-    } else {
-      // The variable exists, check its type and attributes.
-      if (UnsafeStackPtr->getValueType() != StackPtrTy)
-        report_fatal_error(Twine(UnsafeStackPtrVar) + " must have void* type");
-      if (!UnsafeStackPtr->isThreadLocal())
-        report_fatal_error(Twine(UnsafeStackPtrVar) + " must be thread-local");
-    }
-    return UnsafeStackPtr;
-  }
-}
-
 //===----------------------------------------------------------------------===//
 //  Loop Strength Reduction hooks
 //===----------------------------------------------------------------------===//