1 files changed, 0 insertions, 245 deletions
diff --git a/llvm/lib/Target/X86/X86WinFixupBufferSecurityCheck.cpp b/llvm/lib/Target/X86/X86WinFixupBufferSecurityCheck.cpp
deleted file mode 100644
index 5c12af1fee63..000000000000
--- a/llvm/lib/Target/X86/X86WinFixupBufferSecurityCheck.cpp
+++ /dev/null
@@ -1,245 +0,0 @@
-//===- X86WinFixupBufferSecurityCheck.cpp Fix Buffer Security Check Call -===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-// Buffer Security Check implementation inserts windows specific callback into
-// code. On windows, __security_check_cookie call gets call everytime function
-// is return without fixup. Since this function is defined in runtime library,
-// it incures cost of call in dll which simply does comparison and returns most
-// time. With Fixup, We selective move to call in DLL only if comparison fails.
-//===----------------------------------------------------------------------===//
-
-#include "X86.h"
-#include "X86FrameLowering.h"
-#include "X86InstrInfo.h"
-#include "X86Subtarget.h"
-#include "llvm/CodeGen/LivePhysRegs.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/IR/Module.h"
-
-using namespace llvm;
-
-#define DEBUG_TYPE "x86-win-fixup-bscheck"
-
-namespace {
-
-class X86WinFixupBufferSecurityCheckPass : public MachineFunctionPass {
-public:
-  static char ID;
-
-  X86WinFixupBufferSecurityCheckPass() : MachineFunctionPass(ID) {}
-
-  StringRef getPassName() const override {
-    return "X86 Windows Fixup Buffer Security Check";
-  }
-
-  bool runOnMachineFunction(MachineFunction &MF) override;
-
-  std::pair<MachineBasicBlock *, MachineInstr *>
-  getSecurityCheckerBasicBlock(MachineFunction &MF);
-
-  void getGuardCheckSequence(MachineBasicBlock *CurMBB, MachineInstr *CheckCall,
-                             MachineInstr *SeqMI[5]);
-
-  void SplitBasicBlock(MachineBasicBlock *CurMBB, MachineBasicBlock *NewRetMBB,
-                       MachineBasicBlock::iterator SplitIt);
-
-  void FinishBlock(MachineBasicBlock *MBB);
-
-  void FinishFunction(MachineBasicBlock *FailMBB, MachineBasicBlock *NewRetMBB);
-
-  std::pair<MachineInstr *, MachineInstr *>
-  CreateFailCheckSequence(MachineBasicBlock *CurMBB, MachineBasicBlock *FailMBB,
-                          MachineInstr *SeqMI[5]);
-};
-} // end anonymous namespace
-
-char X86WinFixupBufferSecurityCheckPass::ID = 0;
-
-INITIALIZE_PASS(X86WinFixupBufferSecurityCheckPass, DEBUG_TYPE, DEBUG_TYPE,
-                false, false)
-
-FunctionPass *llvm::createX86WinFixupBufferSecurityCheckPass() {
-  return new X86WinFixupBufferSecurityCheckPass();
-}
-
-void X86WinFixupBufferSecurityCheckPass::SplitBasicBlock(
-    MachineBasicBlock *CurMBB, MachineBasicBlock *NewRetMBB,
-    MachineBasicBlock::iterator SplitIt) {
-  NewRetMBB->splice(NewRetMBB->end(), CurMBB, SplitIt, CurMBB->end());
-}
-
-std::pair<MachineBasicBlock *, MachineInstr *>
-X86WinFixupBufferSecurityCheckPass::getSecurityCheckerBasicBlock(
-    MachineFunction &MF) {
-  MachineBasicBlock::reverse_iterator RBegin, REnd;
-
-  for (auto &MBB : llvm::reverse(MF)) {
-    for (RBegin = MBB.rbegin(), REnd = MBB.rend(); RBegin != REnd; ++RBegin) {
-      auto &MI = *RBegin;
-      if (MI.getOpcode() == X86::CALL64pcrel32 &&
-          MI.getNumExplicitOperands() == 1) {
-        auto MO = MI.getOperand(0);
-        if (MO.isGlobal()) {
-          auto Callee = dyn_cast<Function>(MO.getGlobal());
-          if (Callee && Callee->getName() == "__security_check_cookie") {
-            return std::make_pair(&MBB, &MI);
-            break;
-          }
-        }
-      }
-    }
-  }
-  return std::make_pair(nullptr, nullptr);
-}
-
-void X86WinFixupBufferSecurityCheckPass::getGuardCheckSequence(
-    MachineBasicBlock *CurMBB, MachineInstr *CheckCall,
-    MachineInstr *SeqMI[5]) {
-
-  MachineBasicBlock::iterator UIt(CheckCall);
-  MachineBasicBlock::reverse_iterator DIt(CheckCall);
-  // Seq From StackUp to Stack Down Is fixed.
-  // ADJCALLSTACKUP64
-  ++UIt;
-  SeqMI[4] = &*UIt;
-
-  // CALL __security_check_cookie
-  SeqMI[3] = CheckCall;
-
-  // COPY function slot cookie
-  ++DIt;
-  SeqMI[2] = &*DIt;
-
-  // ADJCALLSTACKDOWN64
-  ++DIt;
-  SeqMI[1] = &*DIt;
-
-  MachineBasicBlock::reverse_iterator XIt(SeqMI[1]);
-  for (; XIt != CurMBB->rbegin(); ++XIt) {
-    auto &CI = *XIt;
-    if ((CI.getOpcode() == X86::XOR64_FP) || (CI.getOpcode() == X86::XOR32_FP))
-      break;
-  }
-  SeqMI[0] = &*XIt;
-}
-
-std::pair<MachineInstr *, MachineInstr *>
-X86WinFixupBufferSecurityCheckPass::CreateFailCheckSequence(
-    MachineBasicBlock *CurMBB, MachineBasicBlock *FailMBB,
-    MachineInstr *SeqMI[5]) {
-
-  auto MF = CurMBB->getParent();
-
-  Module &M = *MF->getFunction().getParent();
-  GlobalVariable *GV = M.getGlobalVariable("__security_cookie");
-  assert(GV && " Security Cookie was not installed!");
-
-  const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
-
-  MachineInstr *GuardXor = SeqMI[0];
-  MachineBasicBlock::iterator InsertPt(GuardXor);
-  ++InsertPt;
-
-  // Compare security_Cookie with XOR_Val, if not same, we have violation
-  auto CMI = BuildMI(*CurMBB, InsertPt, DebugLoc(), TII->get(X86::CMP64rm))
-                 .addReg(GuardXor->getOperand(0).getReg())
-                 .addReg(X86::RIP)
-                 .addImm(1)
-                 .addReg(X86::NoRegister)
-                 .addGlobalAddress(GV)
-                 .addReg(X86::NoRegister);
-
-  BuildMI(*CurMBB, InsertPt, DebugLoc(), TII->get(X86::JCC_1))
-      .addMBB(FailMBB)
-      .addImm(X86::COND_NE);
-
-  auto JMI = BuildMI(*CurMBB, InsertPt, DebugLoc(), TII->get(X86::JMP_1));
-
-  return std::make_pair(CMI.getInstr(), JMI.getInstr());
-}
-
-void X86WinFixupBufferSecurityCheckPass::FinishBlock(MachineBasicBlock *MBB) {
-  LivePhysRegs LiveRegs;
-  computeAndAddLiveIns(LiveRegs, *MBB);
-}
-
-void X86WinFixupBufferSecurityCheckPass::FinishFunction(
-    MachineBasicBlock *FailMBB, MachineBasicBlock *NewRetMBB) {
-  FailMBB->getParent()->RenumberBlocks();
-  // FailMBB includes call to MSCV RT  where is __security_check_cookie
-  // function is called. This function uses regcall and it expects cookie
-  // value from stack slot.( even if this is modified)
-  // Before going further we compute back livein for this block to make sure
-  // it is live and provided.
-  FinishBlock(FailMBB);
-  FinishBlock(NewRetMBB);
-}
-
-bool X86WinFixupBufferSecurityCheckPass::runOnMachineFunction(
-    MachineFunction &MF) {
-  bool Changed = false;
-  const X86Subtarget &STI = MF.getSubtarget<X86Subtarget>();
-
-  if (!(STI.isTargetWindowsItanium() || STI.isTargetWindowsMSVC()))
-    return Changed;
-
-  // Check if security cookie was installed or not
-  Module &M = *MF.getFunction().getParent();
-  GlobalVariable *GV = M.getGlobalVariable("__security_cookie");
-  if (!GV)
-    return Changed;
-
-  const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
-
-  // Check if security check cookie was installed or not
-  auto [CurMBB, CheckCall] = getSecurityCheckerBasicBlock(MF);
-
-  if (!CheckCall)
-    return Changed;
-
-  MachineBasicBlock *FailMBB = MF.CreateMachineBasicBlock();
-  MachineBasicBlock *NewRetMBB = MF.CreateMachineBasicBlock();
-
-  MF.insert(MF.end(), NewRetMBB);
-  MF.insert(MF.end(), FailMBB);
-
-  MachineInstr *SeqMI[5];
-  getGuardCheckSequence(CurMBB, CheckCall, SeqMI);
-  // MachineInstr * GuardXor  = SeqMI[0];
-
-  auto FailSeqRange = CreateFailCheckSequence(CurMBB, FailMBB, SeqMI);
-  MachineInstrBuilder JMI(MF, FailSeqRange.second);
-
-  // After Inserting JMP_1, we can not have two terminators
-  // in same block, split CurrentMBB after JMP_1
-  MachineBasicBlock::iterator SplitIt(SeqMI[4]);
-  ++SplitIt;
-  SplitBasicBlock(CurMBB, NewRetMBB, SplitIt);
-
-  // Fill up Failure Routine, move Fail Check Squence from CurMBB to FailMBB
-  MachineBasicBlock::iterator U1It(SeqMI[1]);
-  MachineBasicBlock::iterator U2It(SeqMI[4]);
-  ++U2It;
-  FailMBB->splice(FailMBB->end(), CurMBB, U1It, U2It);
-  BuildMI(*FailMBB, FailMBB->end(), DebugLoc(), TII->get(X86::INT3));
-
-  // Move left over instruction after StackUp
-  // from Current Basic BLocks into New Return Block
-  JMI.addMBB(NewRetMBB);
-  MachineBasicBlock::iterator SplicePt(JMI.getInstr());
-  ++SplicePt;
-  if (SplicePt != CurMBB->end())
-    NewRetMBB->splice(NewRetMBB->end(), CurMBB, SplicePt);
-
-  // Restructure Basic Blocks
-  CurMBB->addSuccessor(NewRetMBB);
-  CurMBB->addSuccessor(FailMBB);
-
-  FinishFunction(FailMBB, NewRetMBB);
-  return !Changed;
-}