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-rw-r--r--llvm/lib/Transforms/CFGuard/CFGuard.cpp612
1 files changed, 306 insertions, 306 deletions
diff --git a/llvm/lib/Transforms/CFGuard/CFGuard.cpp b/llvm/lib/Transforms/CFGuard/CFGuard.cpp
index 9517e21ffde..3eca00691e0 100644
--- a/llvm/lib/Transforms/CFGuard/CFGuard.cpp
+++ b/llvm/lib/Transforms/CFGuard/CFGuard.cpp
@@ -1,307 +1,307 @@
-//===-- CFGuard.cpp - Control Flow Guard checks -----------------*- C++ -*-===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-///
-/// \file
-/// This file contains the IR transform to add Microsoft's Control Flow Guard
-/// checks on Windows targets.
-///
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/CFGuard.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/Triple.h"
-#include "llvm/IR/CallingConv.h"
-#include "llvm/IR/IRBuilder.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
-
-using namespace llvm;
-
-using OperandBundleDef = OperandBundleDefT<Value *>;
-
-#define DEBUG_TYPE "cfguard"
-
-STATISTIC(CFGuardCounter, "Number of Control Flow Guard checks added");
-
-namespace {
-
-/// Adds Control Flow Guard (CFG) checks on indirect function calls/invokes.
-/// These checks ensure that the target address corresponds to the start of an
-/// address-taken function. X86_64 targets use the CF_Dispatch mechanism. X86,
-/// ARM, and AArch64 targets use the CF_Check machanism.
-class CFGuard : public FunctionPass {
-public:
- static char ID;
-
- enum Mechanism { CF_Check, CF_Dispatch };
-
- // Default constructor required for the INITIALIZE_PASS macro.
- CFGuard() : FunctionPass(ID) {
- initializeCFGuardPass(*PassRegistry::getPassRegistry());
- // By default, use the guard check mechanism.
- GuardMechanism = CF_Check;
- }
-
- // Recommended constructor used to specify the type of guard mechanism.
- CFGuard(Mechanism Var) : FunctionPass(ID) {
- initializeCFGuardPass(*PassRegistry::getPassRegistry());
- GuardMechanism = Var;
- }
-
- /// Inserts a Control Flow Guard (CFG) check on an indirect call using the CFG
- /// check mechanism. When the image is loaded, the loader puts the appropriate
- /// guard check function pointer in the __guard_check_icall_fptr global
- /// symbol. This checks that the target address is a valid address-taken
- /// function. The address of the target function is passed to the guard check
- /// function in an architecture-specific register (e.g. ECX on 32-bit X86,
- /// X15 on Aarch64, and R0 on ARM). The guard check function has no return
- /// value (if the target is invalid, the guard check funtion will raise an
- /// error).
- ///
- /// For example, the following LLVM IR:
- /// \code
- /// %func_ptr = alloca i32 ()*, align 8
- /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
- /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
- /// %1 = call i32 %0()
- /// \endcode
- ///
- /// is transformed to:
- /// \code
- /// %func_ptr = alloca i32 ()*, align 8
- /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
- /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
- /// %1 = load void (i8*)*, void (i8*)** @__guard_check_icall_fptr
- /// %2 = bitcast i32 ()* %0 to i8*
- /// call cfguard_checkcc void %1(i8* %2)
- /// %3 = call i32 %0()
- /// \endcode
- ///
- /// For example, the following X86 assembly code:
- /// \code
- /// movl $_target_func, %eax
- /// calll *%eax
- /// \endcode
- ///
- /// is transformed to:
- /// \code
- /// movl $_target_func, %ecx
- /// calll *___guard_check_icall_fptr
- /// calll *%ecx
- /// \endcode
- ///
- /// \param CB indirect call to instrument.
- void insertCFGuardCheck(CallBase *CB);
-
- /// Inserts a Control Flow Guard (CFG) check on an indirect call using the CFG
- /// dispatch mechanism. When the image is loaded, the loader puts the
- /// appropriate guard check function pointer in the
- /// __guard_dispatch_icall_fptr global symbol. This checks that the target
- /// address is a valid address-taken function and, if so, tail calls the
- /// target. The target address is passed in an architecture-specific register
- /// (e.g. RAX on X86_64), with all other arguments for the target function
- /// passed as usual.
- ///
- /// For example, the following LLVM IR:
- /// \code
- /// %func_ptr = alloca i32 ()*, align 8
- /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
- /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
- /// %1 = call i32 %0()
- /// \endcode
- ///
- /// is transformed to:
- /// \code
- /// %func_ptr = alloca i32 ()*, align 8
- /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
- /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
- /// %1 = load i32 ()*, i32 ()** @__guard_dispatch_icall_fptr
- /// %2 = call i32 %1() [ "cfguardtarget"(i32 ()* %0) ]
- /// \endcode
- ///
- /// For example, the following X86_64 assembly code:
- /// \code
- /// leaq target_func(%rip), %rax
- /// callq *%rax
- /// \endcode
- ///
- /// is transformed to:
- /// \code
- /// leaq target_func(%rip), %rax
- /// callq *__guard_dispatch_icall_fptr(%rip)
- /// \endcode
- ///
- /// \param CB indirect call to instrument.
- void insertCFGuardDispatch(CallBase *CB);
-
- bool doInitialization(Module &M) override;
- bool runOnFunction(Function &F) override;
-
-private:
- // Only add checks if the module has the cfguard=2 flag.
- int cfguard_module_flag = 0;
- Mechanism GuardMechanism = CF_Check;
- FunctionType *GuardFnType = nullptr;
- PointerType *GuardFnPtrType = nullptr;
- Constant *GuardFnGlobal = nullptr;
-};
-
-} // end anonymous namespace
-
-void CFGuard::insertCFGuardCheck(CallBase *CB) {
-
- assert(Triple(CB->getModule()->getTargetTriple()).isOSWindows() &&
- "Only applicable for Windows targets");
- assert(CB->isIndirectCall() &&
- "Control Flow Guard checks can only be added to indirect calls");
-
- IRBuilder<> B(CB);
- Value *CalledOperand = CB->getCalledOperand();
-
- // Load the global symbol as a pointer to the check function.
- LoadInst *GuardCheckLoad = B.CreateLoad(GuardFnPtrType, GuardFnGlobal);
-
- // Create new call instruction. The CFGuard check should always be a call,
- // even if the original CallBase is an Invoke or CallBr instruction.
- CallInst *GuardCheck =
- B.CreateCall(GuardFnType, GuardCheckLoad,
- {B.CreateBitCast(CalledOperand, B.getInt8PtrTy())});
-
- // Ensure that the first argument is passed in the correct register
- // (e.g. ECX on 32-bit X86 targets).
- GuardCheck->setCallingConv(CallingConv::CFGuard_Check);
-}
-
-void CFGuard::insertCFGuardDispatch(CallBase *CB) {
-
- assert(Triple(CB->getModule()->getTargetTriple()).isOSWindows() &&
- "Only applicable for Windows targets");
- assert(CB->isIndirectCall() &&
- "Control Flow Guard checks can only be added to indirect calls");
-
- IRBuilder<> B(CB);
- Value *CalledOperand = CB->getCalledOperand();
- Type *CalledOperandType = CalledOperand->getType();
-
- // Cast the guard dispatch global to the type of the called operand.
- PointerType *PTy = PointerType::get(CalledOperandType, 0);
- if (GuardFnGlobal->getType() != PTy)
- GuardFnGlobal = ConstantExpr::getBitCast(GuardFnGlobal, PTy);
-
- // Load the global as a pointer to a function of the same type.
- LoadInst *GuardDispatchLoad = B.CreateLoad(CalledOperandType, GuardFnGlobal);
-
- // Add the original call target as a cfguardtarget operand bundle.
- SmallVector<llvm::OperandBundleDef, 1> Bundles;
- CB->getOperandBundlesAsDefs(Bundles);
- Bundles.emplace_back("cfguardtarget", CalledOperand);
-
- // Create a copy of the call/invoke instruction and add the new bundle.
- CallBase *NewCB;
- if (CallInst *CI = dyn_cast<CallInst>(CB)) {
- NewCB = CallInst::Create(CI, Bundles, CB);
- } else {
- assert(isa<InvokeInst>(CB) && "Unknown indirect call type");
- InvokeInst *II = cast<InvokeInst>(CB);
- NewCB = llvm::InvokeInst::Create(II, Bundles, CB);
- }
-
- // Change the target of the call to be the guard dispatch function.
- NewCB->setCalledOperand(GuardDispatchLoad);
-
- // Replace the original call/invoke with the new instruction.
- CB->replaceAllUsesWith(NewCB);
-
- // Delete the original call/invoke.
- CB->eraseFromParent();
-}
-
-bool CFGuard::doInitialization(Module &M) {
-
- // Check if this module has the cfguard flag and read its value.
- if (auto *MD =
- mdconst::extract_or_null<ConstantInt>(M.getModuleFlag("cfguard")))
- cfguard_module_flag = MD->getZExtValue();
-
- // Skip modules for which CFGuard checks have been disabled.
- if (cfguard_module_flag != 2)
- return false;
-
- // Set up prototypes for the guard check and dispatch functions.
- GuardFnType = FunctionType::get(Type::getVoidTy(M.getContext()),
- {Type::getInt8PtrTy(M.getContext())}, false);
- GuardFnPtrType = PointerType::get(GuardFnType, 0);
-
- // Get or insert the guard check or dispatch global symbols.
- if (GuardMechanism == CF_Check) {
- GuardFnGlobal =
- M.getOrInsertGlobal("__guard_check_icall_fptr", GuardFnPtrType);
- } else {
- assert(GuardMechanism == CF_Dispatch && "Invalid CFGuard mechanism");
- GuardFnGlobal =
- M.getOrInsertGlobal("__guard_dispatch_icall_fptr", GuardFnPtrType);
- }
-
- return true;
-}
-
-bool CFGuard::runOnFunction(Function &F) {
-
- // Skip modules and functions for which CFGuard checks have been disabled.
- if (cfguard_module_flag != 2 || F.hasFnAttribute(Attribute::NoCfCheck))
- return false;
-
- SmallVector<CallBase *, 8> IndirectCalls;
-
- // Iterate over the instructions to find all indirect call/invoke/callbr
- // instructions. Make a separate list of pointers to indirect
- // call/invoke/callbr instructions because the original instructions will be
- // deleted as the checks are added.
- for (BasicBlock &BB : F.getBasicBlockList()) {
- for (Instruction &I : BB.getInstList()) {
- auto *CB = dyn_cast<CallBase>(&I);
- if (CB && CB->isIndirectCall()) {
- IndirectCalls.push_back(CB);
- CFGuardCounter++;
- }
- }
- }
-
- // If no checks are needed, return early and add this attribute to indicate
- // that subsequent CFGuard passes can skip this function.
- if (IndirectCalls.empty()) {
- F.addFnAttr(Attribute::NoCfCheck);
- return false;
- }
-
- // For each indirect call/invoke, add the appropriate dispatch or check.
- if (GuardMechanism == CF_Dispatch) {
- for (CallBase *CB : IndirectCalls) {
- insertCFGuardDispatch(CB);
- }
- } else {
- for (CallBase *CB : IndirectCalls) {
- insertCFGuardCheck(CB);
- }
- }
-
- return true;
-}
-
-char CFGuard::ID = 0;
-INITIALIZE_PASS(CFGuard, "CFGuard", "CFGuard", false, false)
-
-FunctionPass *llvm::createCFGuardCheckPass() {
- return new CFGuard(CFGuard::CF_Check);
-}
-
-FunctionPass *llvm::createCFGuardDispatchPass() {
- return new CFGuard(CFGuard::CF_Dispatch);
+//===-- CFGuard.cpp - Control Flow Guard checks -----------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the IR transform to add Microsoft's Control Flow Guard
+/// checks on Windows targets.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/CFGuard.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/IR/CallingConv.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+
+using namespace llvm;
+
+using OperandBundleDef = OperandBundleDefT<Value *>;
+
+#define DEBUG_TYPE "cfguard"
+
+STATISTIC(CFGuardCounter, "Number of Control Flow Guard checks added");
+
+namespace {
+
+/// Adds Control Flow Guard (CFG) checks on indirect function calls/invokes.
+/// These checks ensure that the target address corresponds to the start of an
+/// address-taken function. X86_64 targets use the CF_Dispatch mechanism. X86,
+/// ARM, and AArch64 targets use the CF_Check machanism.
+class CFGuard : public FunctionPass {
+public:
+ static char ID;
+
+ enum Mechanism { CF_Check, CF_Dispatch };
+
+ // Default constructor required for the INITIALIZE_PASS macro.
+ CFGuard() : FunctionPass(ID) {
+ initializeCFGuardPass(*PassRegistry::getPassRegistry());
+ // By default, use the guard check mechanism.
+ GuardMechanism = CF_Check;
+ }
+
+ // Recommended constructor used to specify the type of guard mechanism.
+ CFGuard(Mechanism Var) : FunctionPass(ID) {
+ initializeCFGuardPass(*PassRegistry::getPassRegistry());
+ GuardMechanism = Var;
+ }
+
+ /// Inserts a Control Flow Guard (CFG) check on an indirect call using the CFG
+ /// check mechanism. When the image is loaded, the loader puts the appropriate
+ /// guard check function pointer in the __guard_check_icall_fptr global
+ /// symbol. This checks that the target address is a valid address-taken
+ /// function. The address of the target function is passed to the guard check
+ /// function in an architecture-specific register (e.g. ECX on 32-bit X86,
+ /// X15 on Aarch64, and R0 on ARM). The guard check function has no return
+ /// value (if the target is invalid, the guard check funtion will raise an
+ /// error).
+ ///
+ /// For example, the following LLVM IR:
+ /// \code
+ /// %func_ptr = alloca i32 ()*, align 8
+ /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
+ /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
+ /// %1 = call i32 %0()
+ /// \endcode
+ ///
+ /// is transformed to:
+ /// \code
+ /// %func_ptr = alloca i32 ()*, align 8
+ /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
+ /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
+ /// %1 = load void (i8*)*, void (i8*)** @__guard_check_icall_fptr
+ /// %2 = bitcast i32 ()* %0 to i8*
+ /// call cfguard_checkcc void %1(i8* %2)
+ /// %3 = call i32 %0()
+ /// \endcode
+ ///
+ /// For example, the following X86 assembly code:
+ /// \code
+ /// movl $_target_func, %eax
+ /// calll *%eax
+ /// \endcode
+ ///
+ /// is transformed to:
+ /// \code
+ /// movl $_target_func, %ecx
+ /// calll *___guard_check_icall_fptr
+ /// calll *%ecx
+ /// \endcode
+ ///
+ /// \param CB indirect call to instrument.
+ void insertCFGuardCheck(CallBase *CB);
+
+ /// Inserts a Control Flow Guard (CFG) check on an indirect call using the CFG
+ /// dispatch mechanism. When the image is loaded, the loader puts the
+ /// appropriate guard check function pointer in the
+ /// __guard_dispatch_icall_fptr global symbol. This checks that the target
+ /// address is a valid address-taken function and, if so, tail calls the
+ /// target. The target address is passed in an architecture-specific register
+ /// (e.g. RAX on X86_64), with all other arguments for the target function
+ /// passed as usual.
+ ///
+ /// For example, the following LLVM IR:
+ /// \code
+ /// %func_ptr = alloca i32 ()*, align 8
+ /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
+ /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
+ /// %1 = call i32 %0()
+ /// \endcode
+ ///
+ /// is transformed to:
+ /// \code
+ /// %func_ptr = alloca i32 ()*, align 8
+ /// store i32 ()* @target_func, i32 ()** %func_ptr, align 8
+ /// %0 = load i32 ()*, i32 ()** %func_ptr, align 8
+ /// %1 = load i32 ()*, i32 ()** @__guard_dispatch_icall_fptr
+ /// %2 = call i32 %1() [ "cfguardtarget"(i32 ()* %0) ]
+ /// \endcode
+ ///
+ /// For example, the following X86_64 assembly code:
+ /// \code
+ /// leaq target_func(%rip), %rax
+ /// callq *%rax
+ /// \endcode
+ ///
+ /// is transformed to:
+ /// \code
+ /// leaq target_func(%rip), %rax
+ /// callq *__guard_dispatch_icall_fptr(%rip)
+ /// \endcode
+ ///
+ /// \param CB indirect call to instrument.
+ void insertCFGuardDispatch(CallBase *CB);
+
+ bool doInitialization(Module &M) override;
+ bool runOnFunction(Function &F) override;
+
+private:
+ // Only add checks if the module has the cfguard=2 flag.
+ int cfguard_module_flag = 0;
+ Mechanism GuardMechanism = CF_Check;
+ FunctionType *GuardFnType = nullptr;
+ PointerType *GuardFnPtrType = nullptr;
+ Constant *GuardFnGlobal = nullptr;
+};
+
+} // end anonymous namespace
+
+void CFGuard::insertCFGuardCheck(CallBase *CB) {
+
+ assert(Triple(CB->getModule()->getTargetTriple()).isOSWindows() &&
+ "Only applicable for Windows targets");
+ assert(CB->isIndirectCall() &&
+ "Control Flow Guard checks can only be added to indirect calls");
+
+ IRBuilder<> B(CB);
+ Value *CalledOperand = CB->getCalledOperand();
+
+ // Load the global symbol as a pointer to the check function.
+ LoadInst *GuardCheckLoad = B.CreateLoad(GuardFnPtrType, GuardFnGlobal);
+
+ // Create new call instruction. The CFGuard check should always be a call,
+ // even if the original CallBase is an Invoke or CallBr instruction.
+ CallInst *GuardCheck =
+ B.CreateCall(GuardFnType, GuardCheckLoad,
+ {B.CreateBitCast(CalledOperand, B.getInt8PtrTy())});
+
+ // Ensure that the first argument is passed in the correct register
+ // (e.g. ECX on 32-bit X86 targets).
+ GuardCheck->setCallingConv(CallingConv::CFGuard_Check);
+}
+
+void CFGuard::insertCFGuardDispatch(CallBase *CB) {
+
+ assert(Triple(CB->getModule()->getTargetTriple()).isOSWindows() &&
+ "Only applicable for Windows targets");
+ assert(CB->isIndirectCall() &&
+ "Control Flow Guard checks can only be added to indirect calls");
+
+ IRBuilder<> B(CB);
+ Value *CalledOperand = CB->getCalledOperand();
+ Type *CalledOperandType = CalledOperand->getType();
+
+ // Cast the guard dispatch global to the type of the called operand.
+ PointerType *PTy = PointerType::get(CalledOperandType, 0);
+ if (GuardFnGlobal->getType() != PTy)
+ GuardFnGlobal = ConstantExpr::getBitCast(GuardFnGlobal, PTy);
+
+ // Load the global as a pointer to a function of the same type.
+ LoadInst *GuardDispatchLoad = B.CreateLoad(CalledOperandType, GuardFnGlobal);
+
+ // Add the original call target as a cfguardtarget operand bundle.
+ SmallVector<llvm::OperandBundleDef, 1> Bundles;
+ CB->getOperandBundlesAsDefs(Bundles);
+ Bundles.emplace_back("cfguardtarget", CalledOperand);
+
+ // Create a copy of the call/invoke instruction and add the new bundle.
+ CallBase *NewCB;
+ if (CallInst *CI = dyn_cast<CallInst>(CB)) {
+ NewCB = CallInst::Create(CI, Bundles, CB);
+ } else {
+ assert(isa<InvokeInst>(CB) && "Unknown indirect call type");
+ InvokeInst *II = cast<InvokeInst>(CB);
+ NewCB = llvm::InvokeInst::Create(II, Bundles, CB);
+ }
+
+ // Change the target of the call to be the guard dispatch function.
+ NewCB->setCalledOperand(GuardDispatchLoad);
+
+ // Replace the original call/invoke with the new instruction.
+ CB->replaceAllUsesWith(NewCB);
+
+ // Delete the original call/invoke.
+ CB->eraseFromParent();
+}
+
+bool CFGuard::doInitialization(Module &M) {
+
+ // Check if this module has the cfguard flag and read its value.
+ if (auto *MD =
+ mdconst::extract_or_null<ConstantInt>(M.getModuleFlag("cfguard")))
+ cfguard_module_flag = MD->getZExtValue();
+
+ // Skip modules for which CFGuard checks have been disabled.
+ if (cfguard_module_flag != 2)
+ return false;
+
+ // Set up prototypes for the guard check and dispatch functions.
+ GuardFnType = FunctionType::get(Type::getVoidTy(M.getContext()),
+ {Type::getInt8PtrTy(M.getContext())}, false);
+ GuardFnPtrType = PointerType::get(GuardFnType, 0);
+
+ // Get or insert the guard check or dispatch global symbols.
+ if (GuardMechanism == CF_Check) {
+ GuardFnGlobal =
+ M.getOrInsertGlobal("__guard_check_icall_fptr", GuardFnPtrType);
+ } else {
+ assert(GuardMechanism == CF_Dispatch && "Invalid CFGuard mechanism");
+ GuardFnGlobal =
+ M.getOrInsertGlobal("__guard_dispatch_icall_fptr", GuardFnPtrType);
+ }
+
+ return true;
+}
+
+bool CFGuard::runOnFunction(Function &F) {
+
+ // Skip modules and functions for which CFGuard checks have been disabled.
+ if (cfguard_module_flag != 2 || F.hasFnAttribute(Attribute::NoCfCheck))
+ return false;
+
+ SmallVector<CallBase *, 8> IndirectCalls;
+
+ // Iterate over the instructions to find all indirect call/invoke/callbr
+ // instructions. Make a separate list of pointers to indirect
+ // call/invoke/callbr instructions because the original instructions will be
+ // deleted as the checks are added.
+ for (BasicBlock &BB : F.getBasicBlockList()) {
+ for (Instruction &I : BB.getInstList()) {
+ auto *CB = dyn_cast<CallBase>(&I);
+ if (CB && CB->isIndirectCall()) {
+ IndirectCalls.push_back(CB);
+ CFGuardCounter++;
+ }
+ }
+ }
+
+ // If no checks are needed, return early and add this attribute to indicate
+ // that subsequent CFGuard passes can skip this function.
+ if (IndirectCalls.empty()) {
+ F.addFnAttr(Attribute::NoCfCheck);
+ return false;
+ }
+
+ // For each indirect call/invoke, add the appropriate dispatch or check.
+ if (GuardMechanism == CF_Dispatch) {
+ for (CallBase *CB : IndirectCalls) {
+ insertCFGuardDispatch(CB);
+ }
+ } else {
+ for (CallBase *CB : IndirectCalls) {
+ insertCFGuardCheck(CB);
+ }
+ }
+
+ return true;
+}
+
+char CFGuard::ID = 0;
+INITIALIZE_PASS(CFGuard, "CFGuard", "CFGuard", false, false)
+
+FunctionPass *llvm::createCFGuardCheckPass() {
+ return new CFGuard(CFGuard::CF_Check);
+}
+
+FunctionPass *llvm::createCFGuardDispatchPass() {
+ return new CFGuard(CFGuard::CF_Dispatch);
} \ No newline at end of file
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