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

Breaks the hexagon buildbot.

llvm-svn: 250461

4 files changed, 9 insertions, 31 deletions

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 93cb5ecdc6e..b8e30921e8a 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -9921,19 +9921,3 @@ bool AArch64TargetLowering::shouldNormalizeToSelectSequence(LLVMContext &,
                                                             EVT) const {
   return false;
 }
-
-Value *AArch64TargetLowering::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
-  if (!Subtarget->isTargetAndroid())
-    return TargetLowering::getSafeStackPointerLocation(IRB);
-
-  // Android provides a fixed TLS slot for the SafeStack pointer. See the
-  // definition of TLS_SLOT_SAFESTACK in
-  // https://android.googlesource.com/platform/bionic/+/master/libc/private/bionic_tls.h
-  const unsigned TlsOffset = 0x48;
-  Module *M = IRB.GetInsertBlock()->getParent()->getParent();
-  Function *ThreadPointerFunc =
-      Intrinsic::getDeclaration(M, Intrinsic::aarch64_thread_pointer);
-  return IRB.CreatePointerCast(
-      IRB.CreateConstGEP1_32(IRB.CreateCall(ThreadPointerFunc), TlsOffset),
-      Type::getInt8PtrTy(IRB.getContext())->getPointerTo(0));
-}
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.h b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
index 64a2934d1d5..b815f55da6b 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.h
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
@@ -362,10 +362,6 @@ public:
   TargetLoweringBase::LegalizeTypeAction
   getPreferredVectorAction(EVT VT) const override;
 
-  /// If the target has a standard location for the unsafe stack pointer,
-  /// returns the address of that location. Otherwise, returns nullptr.
-  Value *getSafeStackPointerLocation(IRBuilder<> &IRB) const override;
-
 private:
   bool isExtFreeImpl(const Instruction *Ext) const override;
 
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 9df41ec9e6d..618290a257a 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -2086,14 +2086,14 @@ bool X86TargetLowering::getStackCookieLocation(unsigned &AddressSpace,
   return true;
 }
 
-Value *X86TargetLowering::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
+/// Android provides a fixed TLS slot for the SafeStack pointer.
+/// See the definition of TLS_SLOT_SAFESTACK in
+/// https://android.googlesource.com/platform/bionic/+/master/libc/private/bionic_tls.h
+bool X86TargetLowering::getSafeStackPointerLocation(unsigned &AddressSpace,
+                                                    unsigned &Offset) const {
   if (!Subtarget->isTargetAndroid())
-    return TargetLowering::getSafeStackPointerLocation(IRB);
+    return false;
 
-  // Android provides a fixed TLS slot for the SafeStack pointer. See the
-  // definition of TLS_SLOT_SAFESTACK in
-  // https://android.googlesource.com/platform/bionic/+/master/libc/private/bionic_tls.h
-  unsigned AddressSpace, Offset;
   if (Subtarget->is64Bit()) {
     // %fs:0x48, unless we're using a Kernel code model, in which case it's %gs:
     Offset = 0x48;
@@ -2106,10 +2106,7 @@ Value *X86TargetLowering::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
     Offset = 0x24;
     AddressSpace = 256;
   }
-
-  return ConstantExpr::getIntToPtr(
-      ConstantInt::get(Type::getInt32Ty(IRB.getContext()), Offset),
-      Type::getInt8PtrTy(IRB.getContext())->getPointerTo(AddressSpace));
+  return true;
 }
 
 bool X86TargetLowering::isNoopAddrSpaceCast(unsigned SrcAS,
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index 713a4d66ad7..0028eb0c82c 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -901,7 +901,8 @@ namespace llvm {
     /// Return true if the target stores SafeStack pointer at a fixed offset in
     /// some non-standard address space, and populates the address space and
     /// offset as appropriate.
-    Value *getSafeStackPointerLocation(IRBuilder<> &IRB) const override;
+    bool getSafeStackPointerLocation(unsigned &AddressSpace,
+                                     unsigned &Offset) const override;
 
     SDValue BuildFILD(SDValue Op, EVT SrcVT, SDValue Chain, SDValue StackSlot,
                       SelectionDAG &DAG) const;