Revert r319490 "XOR the frame pointer with the stack cookie when protecting the stack"

This broke the Chromium build (crbug.com/791714). Reverting while investigating.

> Summary: This strengthens the guard and matches MSVC.
>
> Reviewers: hans, etienneb
>
> Subscribers: hiraditya, JDevlieghere, vlad.tsyrklevich, llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D40622
>
> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319490 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-svn: 319706

1 files changed, 0 insertions, 13 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index de3df34ec44..073b4e01377 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -1687,19 +1687,6 @@ bool X86TargetLowering::useLoadStackGuardNode() const {
   return Subtarget.isTargetMachO() && Subtarget.is64Bit();
 }
 
-bool X86TargetLowering::useStackGuardXorFP() const {
-  // Currently only MSVC CRTs XOR the frame pointer into the stack guard value.
-  return Subtarget.getTargetTriple().isOSMSVCRT();
-}
-
-SDValue X86TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
-                                               const SDLoc &DL) const {
-  EVT PtrTy = getPointerTy(DAG.getDataLayout());
-  unsigned XorOp = Subtarget.is64Bit() ? X86::XOR64_FP : X86::XOR32_FP;
-  MachineSDNode *Node = DAG.getMachineNode(XorOp, DL, PtrTy, Val);
-  return SDValue(Node, 0);
-}
-
 TargetLoweringBase::LegalizeTypeAction
 X86TargetLowering::getPreferredVectorAction(EVT VT) const {
   if (ExperimentalVectorWideningLegalization &&