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[safestack] Protect byval function arguments.
Detect unsafe byval function arguments and move them to the unsafe stack. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254353 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evgeniy Stepanov
parent
390ced1108
commit
dd121fc847
@ -271,10 +271,20 @@ bool LowerDbgDeclare(Function &F);
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/// an alloca, if any.
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DbgDeclareInst *FindAllocaDbgDeclare(Value *V);
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/// \brief Replaces llvm.dbg.declare instruction when an alloca is replaced with
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/// a new value. If Deref is true, an additional DW_OP_deref is prepended to the
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/// expression. If Offset is non-zero, a constant displacement is added to the
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/// expression (after the optional Deref). Offset can be negative.
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/// \brief Replaces llvm.dbg.declare instruction when the address it describes
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/// is replaced with a new value. If Deref is true, an additional DW_OP_deref is
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/// prepended to the expression. If Offset is non-zero, a constant displacement
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/// is added to the expression (after the optional Deref). Offset can be
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/// negative.
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bool replaceDbgDeclare(Value *Address, Value *NewAddress,
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Instruction *InsertBefore, DIBuilder &Builder,
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bool Deref, int Offset);
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/// \brief Replaces llvm.dbg.declare instruction when the alloca it describes
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/// is replaced with a new value. If Deref is true, an additional DW_OP_deref is
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/// prepended to the expression. If Offset is non-zero, a constant displacement
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/// is added to the expression (after the optional Deref). Offset can be
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/// negative. New llvm.dbg.declare is inserted immediately before AI.
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bool replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
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DIBuilder &Builder, bool Deref, int Offset = 0);
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@ -57,6 +57,7 @@ STATISTIC(NumUnsafeStackRestorePointsFunctions,
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STATISTIC(NumAllocas, "Total number of allocas");
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STATISTIC(NumUnsafeStaticAllocas, "Number of unsafe static allocas");
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STATISTIC(NumUnsafeDynamicAllocas, "Number of unsafe dynamic allocas");
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STATISTIC(NumUnsafeByValArguments, "Number of unsafe byval arguments");
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STATISTIC(NumUnsafeStackRestorePoints, "Number of setjmps and landingpads");
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} // namespace llvm
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@ -68,14 +69,14 @@ namespace {
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///
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/// The implementation simply replaces all mentions of the alloca with zero.
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class AllocaOffsetRewriter : public SCEVRewriteVisitor<AllocaOffsetRewriter> {
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const AllocaInst *AI;
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const Value *AllocaPtr;
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public:
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AllocaOffsetRewriter(ScalarEvolution &SE, const AllocaInst *AI)
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: SCEVRewriteVisitor(SE), AI(AI) {}
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AllocaOffsetRewriter(ScalarEvolution &SE, const Value *AllocaPtr)
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: SCEVRewriteVisitor(SE), AllocaPtr(AllocaPtr) {}
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const SCEV *visitUnknown(const SCEVUnknown *Expr) {
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if (Expr->getValue() == AI)
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if (Expr->getValue() == AllocaPtr)
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return SE.getZero(Expr->getType());
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return Expr;
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}
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@ -115,6 +116,7 @@ class SafeStack : public FunctionPass {
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/// given function and append them to the respective vectors.
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void findInsts(Function &F, SmallVectorImpl<AllocaInst *> &StaticAllocas,
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SmallVectorImpl<AllocaInst *> &DynamicAllocas,
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SmallVectorImpl<Argument *> &ByValArguments,
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SmallVectorImpl<ReturnInst *> &Returns,
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SmallVectorImpl<Instruction *> &StackRestorePoints);
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@ -130,6 +132,7 @@ class SafeStack : public FunctionPass {
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/// allocas are allocated.
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Value *moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
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ArrayRef<AllocaInst *> StaticAllocas,
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ArrayRef<Argument *> ByValArguments,
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ArrayRef<ReturnInst *> Returns);
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/// \brief Generate code to restore the stack after all stack restore points
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@ -149,11 +152,12 @@ class SafeStack : public FunctionPass {
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AllocaInst *DynamicTop,
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ArrayRef<AllocaInst *> DynamicAllocas);
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bool IsSafeStackAlloca(const AllocaInst *AI);
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bool IsSafeStackAlloca(const Value *AllocaPtr, uint64_t AllocaSize);
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bool IsMemIntrinsicSafe(const MemIntrinsic *MI, const Use &U,
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const AllocaInst *AI);
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bool IsAccessSafe(Value *Addr, uint64_t Size, const AllocaInst *AI);
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const Value *AllocaPtr, uint64_t AllocaSize);
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bool IsAccessSafe(Value *Addr, uint64_t Size, const Value *AllocaPtr,
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uint64_t AllocaSize);
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public:
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static char ID; // Pass identification, replacement for typeid.
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@ -192,20 +196,23 @@ uint64_t SafeStack::getStaticAllocaAllocationSize(const AllocaInst* AI) {
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return Size;
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}
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bool SafeStack::IsAccessSafe(Value *Addr, uint64_t Size, const AllocaInst *AI) {
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AllocaOffsetRewriter Rewriter(*SE, AI);
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bool SafeStack::IsAccessSafe(Value *Addr, uint64_t AccessSize,
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const Value *AllocaPtr, uint64_t AllocaSize) {
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AllocaOffsetRewriter Rewriter(*SE, AllocaPtr);
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const SCEV *Expr = Rewriter.visit(SE->getSCEV(Addr));
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uint64_t BitWidth = SE->getTypeSizeInBits(Expr->getType());
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ConstantRange AccessStartRange = SE->getUnsignedRange(Expr);
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ConstantRange SizeRange =
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ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, Size));
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ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, AccessSize));
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ConstantRange AccessRange = AccessStartRange.add(SizeRange);
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ConstantRange AllocaRange = ConstantRange(
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APInt(BitWidth, 0), APInt(BitWidth, getStaticAllocaAllocationSize(AI)));
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ConstantRange AllocaRange =
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ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, AllocaSize));
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bool Safe = AllocaRange.contains(AccessRange);
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DEBUG(dbgs() << "[SafeStack] Alloca " << *AI << "\n"
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DEBUG(dbgs() << "[SafeStack] "
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<< (isa<AllocaInst>(AllocaPtr) ? "Alloca " : "ByValArgument ")
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<< *AllocaPtr << "\n"
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<< " Access " << *Addr << "\n"
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<< " SCEV " << *Expr
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<< " U: " << SE->getUnsignedRange(Expr)
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@ -218,36 +225,38 @@ bool SafeStack::IsAccessSafe(Value *Addr, uint64_t Size, const AllocaInst *AI) {
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}
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bool SafeStack::IsMemIntrinsicSafe(const MemIntrinsic *MI, const Use &U,
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const AllocaInst *AI) {
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const Value *AllocaPtr,
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uint64_t AllocaSize) {
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// All MemIntrinsics have destination address in Arg0 and size in Arg2.
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if (MI->getRawDest() != U) return true;
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const auto *Len = dyn_cast<ConstantInt>(MI->getLength());
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// Non-constant size => unsafe. FIXME: try SCEV getRange.
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if (!Len) return false;
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return IsAccessSafe(U, Len->getZExtValue(), AI);
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return IsAccessSafe(U, Len->getZExtValue(), AllocaPtr, AllocaSize);
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}
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/// Check whether a given alloca instruction (AI) should be put on the safe
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/// Check whether a given allocation must be put on the safe
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/// stack or not. The function analyzes all uses of AI and checks whether it is
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/// only accessed in a memory safe way (as decided statically).
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bool SafeStack::IsSafeStackAlloca(const AllocaInst *AI) {
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bool SafeStack::IsSafeStackAlloca(const Value *AllocaPtr, uint64_t AllocaSize) {
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// Go through all uses of this alloca and check whether all accesses to the
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// allocated object are statically known to be memory safe and, hence, the
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// object can be placed on the safe stack.
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SmallPtrSet<const Value *, 16> Visited;
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SmallVector<const Instruction *, 8> WorkList;
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WorkList.push_back(AI);
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SmallVector<const Value *, 8> WorkList;
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WorkList.push_back(AllocaPtr);
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// A DFS search through all uses of the alloca in bitcasts/PHI/GEPs/etc.
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while (!WorkList.empty()) {
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const Instruction *V = WorkList.pop_back_val();
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const Value *V = WorkList.pop_back_val();
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for (const Use &UI : V->uses()) {
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auto I = cast<const Instruction>(UI.getUser());
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assert(V == UI.get());
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switch (I->getOpcode()) {
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case Instruction::Load: {
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if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getType()), AI))
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if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getType()), AllocaPtr,
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AllocaSize))
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return false;
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break;
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}
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@ -257,13 +266,13 @@ bool SafeStack::IsSafeStackAlloca(const AllocaInst *AI) {
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case Instruction::Store: {
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if (V == I->getOperand(0)) {
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// Stored the pointer - conservatively assume it may be unsafe.
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
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<< "\n store of address: " << *I << "\n");
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return false;
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}
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if (!IsAccessSafe(
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UI, DL->getTypeStoreSize(I->getOperand(0)->getType()), AI))
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if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getOperand(0)->getType()),
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AllocaPtr, AllocaSize))
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return false;
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break;
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}
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@ -283,8 +292,8 @@ bool SafeStack::IsSafeStackAlloca(const AllocaInst *AI) {
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}
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if (const MemIntrinsic *MI = dyn_cast<MemIntrinsic>(I)) {
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if (!IsMemIntrinsicSafe(MI, UI, AI)) {
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
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if (!IsMemIntrinsicSafe(MI, UI, AllocaPtr, AllocaSize)) {
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
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<< "\n unsafe memintrinsic: " << *I
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<< "\n");
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return false;
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@ -302,9 +311,9 @@ bool SafeStack::IsSafeStackAlloca(const AllocaInst *AI) {
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ImmutableCallSite::arg_iterator B = CS.arg_begin(), E = CS.arg_end();
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for (ImmutableCallSite::arg_iterator A = B; A != E; ++A)
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if (A->get() == V)
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if (!(CS.doesNotCapture(A - B) &&
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(CS.doesNotAccessMemory(A - B) || CS.doesNotAccessMemory()))) {
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
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if (!(CS.doesNotCapture(A - B) && (CS.doesNotAccessMemory(A - B) ||
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CS.doesNotAccessMemory()))) {
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DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
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<< "\n unsafe call: " << *I << "\n");
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return false;
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}
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@ -355,13 +364,15 @@ Value *SafeStack::getOrCreateUnsafeStackPtr(IRBuilder<> &IRB, Function &F) {
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void SafeStack::findInsts(Function &F,
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SmallVectorImpl<AllocaInst *> &StaticAllocas,
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SmallVectorImpl<AllocaInst *> &DynamicAllocas,
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SmallVectorImpl<Argument *> &ByValArguments,
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SmallVectorImpl<ReturnInst *> &Returns,
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SmallVectorImpl<Instruction *> &StackRestorePoints) {
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for (Instruction &I : instructions(&F)) {
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if (auto AI = dyn_cast<AllocaInst>(&I)) {
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++NumAllocas;
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if (IsSafeStackAlloca(AI))
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uint64_t Size = getStaticAllocaAllocationSize(AI);
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if (IsSafeStackAlloca(AI, Size))
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continue;
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if (AI->isStaticAlloca()) {
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@ -386,6 +397,17 @@ void SafeStack::findInsts(Function &F,
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"gcroot intrinsic not compatible with safestack attribute");
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}
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}
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for (Argument &Arg : F.args()) {
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if (!Arg.hasByValAttr())
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continue;
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uint64_t Size =
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DL->getTypeStoreSize(Arg.getType()->getPointerElementType());
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if (IsSafeStackAlloca(&Arg, Size))
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continue;
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++NumUnsafeByValArguments;
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ByValArguments.push_back(&Arg);
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}
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}
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AllocaInst *
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@ -420,7 +442,7 @@ SafeStack::createStackRestorePoints(IRBuilder<> &IRB, Function &F,
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for (Instruction *I : StackRestorePoints) {
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++NumUnsafeStackRestorePoints;
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IRB.SetInsertPoint(cast<Instruction>(I->getNextNode()));
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IRB.SetInsertPoint(I->getNextNode());
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Value *CurrentTop = DynamicTop ? IRB.CreateLoad(DynamicTop) : StaticTop;
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IRB.CreateStore(CurrentTop, UnsafeStackPtr);
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}
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@ -428,11 +450,10 @@ SafeStack::createStackRestorePoints(IRBuilder<> &IRB, Function &F,
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return DynamicTop;
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}
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Value *
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SafeStack::moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
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ArrayRef<AllocaInst *> StaticAllocas,
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ArrayRef<ReturnInst *> Returns) {
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if (StaticAllocas.empty())
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Value *SafeStack::moveStaticAllocasToUnsafeStack(
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IRBuilder<> &IRB, Function &F, ArrayRef<AllocaInst *> StaticAllocas,
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ArrayRef<Argument *> ByValArguments, ArrayRef<ReturnInst *> Returns) {
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if (StaticAllocas.empty() && ByValArguments.empty())
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return nullptr;
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DIBuilder DIB(*F.getParent());
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@ -454,6 +475,13 @@ SafeStack::moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
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// Compute maximum alignment among static objects on the unsafe stack.
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unsigned MaxAlignment = 0;
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for (Argument *Arg : ByValArguments) {
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Type *Ty = Arg->getType()->getPointerElementType();
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unsigned Align = std::max((unsigned)DL->getPrefTypeAlignment(Ty),
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Arg->getParamAlignment());
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if (Align > MaxAlignment)
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MaxAlignment = Align;
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}
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for (AllocaInst *AI : StaticAllocas) {
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Type *Ty = AI->getAllocatedType();
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unsigned Align =
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@ -465,15 +493,46 @@ SafeStack::moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
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if (MaxAlignment > StackAlignment) {
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// Re-align the base pointer according to the max requested alignment.
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assert(isPowerOf2_32(MaxAlignment));
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IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
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IRB.SetInsertPoint(BasePointer->getNextNode());
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BasePointer = cast<Instruction>(IRB.CreateIntToPtr(
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IRB.CreateAnd(IRB.CreatePtrToInt(BasePointer, IntPtrTy),
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ConstantInt::get(IntPtrTy, ~uint64_t(MaxAlignment - 1))),
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StackPtrTy));
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}
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// Allocate space for every unsafe static AllocaInst on the unsafe stack.
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int64_t StaticOffset = 0; // Current stack top.
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IRB.SetInsertPoint(BasePointer->getNextNode());
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for (Argument *Arg : ByValArguments) {
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Type *Ty = Arg->getType()->getPointerElementType();
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uint64_t Size = DL->getTypeStoreSize(Ty);
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if (Size == 0)
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Size = 1; // Don't create zero-sized stack objects.
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// Ensure the object is properly aligned.
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unsigned Align = std::max((unsigned)DL->getPrefTypeAlignment(Ty),
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Arg->getParamAlignment());
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// Add alignment.
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// NOTE: we ensure that BasePointer itself is aligned to >= Align.
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StaticOffset += Size;
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StaticOffset = RoundUpToAlignment(StaticOffset, Align);
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Value *Off = IRB.CreateGEP(BasePointer, // BasePointer is i8*
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ConstantInt::get(Int32Ty, -StaticOffset));
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Value *NewArg = IRB.CreateBitCast(Off, Arg->getType(),
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Arg->getName() + ".unsafe-byval");
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// Replace alloc with the new location.
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replaceDbgDeclare(Arg, BasePointer, BasePointer->getNextNode(), DIB,
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/*Deref=*/true, -StaticOffset);
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Arg->replaceAllUsesWith(NewArg);
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IRB.SetInsertPoint(cast<Instruction>(NewArg)->getNextNode());
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IRB.CreateMemCpy(Off, Arg, Size, Arg->getParamAlignment());
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}
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// Allocate space for every unsafe static AllocaInst on the unsafe stack.
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for (AllocaInst *AI : StaticAllocas) {
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IRB.SetInsertPoint(AI);
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@ -509,7 +568,7 @@ SafeStack::moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
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StaticOffset = RoundUpToAlignment(StaticOffset, StackAlignment);
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// Update shadow stack pointer in the function epilogue.
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IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
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IRB.SetInsertPoint(BasePointer->getNextNode());
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Value *StaticTop =
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IRB.CreateGEP(BasePointer, ConstantInt::get(Int32Ty, -StaticOffset),
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@ -621,6 +680,7 @@ bool SafeStack::runOnFunction(Function &F) {
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SmallVector<AllocaInst *, 16> StaticAllocas;
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SmallVector<AllocaInst *, 4> DynamicAllocas;
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SmallVector<Argument *, 4> ByValArguments;
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SmallVector<ReturnInst *, 4> Returns;
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// Collect all points where stack gets unwound and needs to be restored
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@ -632,13 +692,15 @@ bool SafeStack::runOnFunction(Function &F) {
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// Find all static and dynamic alloca instructions that must be moved to the
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// unsafe stack, all return instructions and stack restore points.
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findInsts(F, StaticAllocas, DynamicAllocas, Returns, StackRestorePoints);
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findInsts(F, StaticAllocas, DynamicAllocas, ByValArguments, Returns,
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StackRestorePoints);
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if (StaticAllocas.empty() && DynamicAllocas.empty() &&
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StackRestorePoints.empty())
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ByValArguments.empty() && StackRestorePoints.empty())
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return false; // Nothing to do in this function.
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if (!StaticAllocas.empty() || !DynamicAllocas.empty())
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if (!StaticAllocas.empty() || !DynamicAllocas.empty() ||
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!ByValArguments.empty())
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++NumUnsafeStackFunctions; // This function has the unsafe stack.
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if (!StackRestorePoints.empty())
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@ -648,7 +710,8 @@ bool SafeStack::runOnFunction(Function &F) {
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UnsafeStackPtr = getOrCreateUnsafeStackPtr(IRB, F);
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// The top of the unsafe stack after all unsafe static allocas are allocated.
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Value *StaticTop = moveStaticAllocasToUnsafeStack(IRB, F, StaticAllocas, Returns);
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Value *StaticTop = moveStaticAllocasToUnsafeStack(IRB, F, StaticAllocas,
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ByValArguments, Returns);
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// Safe stack object that stores the current unsafe stack top. It is updated
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// as unsafe dynamic (non-constant-sized) allocas are allocated and freed.
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@ -1136,9 +1136,10 @@ DbgDeclareInst *llvm::FindAllocaDbgDeclare(Value *V) {
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return nullptr;
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}
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bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
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DIBuilder &Builder, bool Deref, int Offset) {
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DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI);
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bool llvm::replaceDbgDeclare(Value *Address, Value *NewAddress,
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Instruction *InsertBefore, DIBuilder &Builder,
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bool Deref, int Offset) {
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DbgDeclareInst *DDI = FindAllocaDbgDeclare(Address);
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if (!DDI)
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return false;
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DebugLoc Loc = DDI->getDebugLoc();
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@ -1168,12 +1169,17 @@ bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
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|
||||
// Insert llvm.dbg.declare immediately after the original alloca, and remove
|
||||
// old llvm.dbg.declare.
|
||||
Builder.insertDeclare(NewAllocaAddress, DIVar, DIExpr, Loc,
|
||||
AI->getNextNode());
|
||||
Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
|
||||
DDI->eraseFromParent();
|
||||
return true;
|
||||
}
|
||||
|
||||
bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
|
||||
DIBuilder &Builder, bool Deref, int Offset) {
|
||||
return replaceDbgDeclare(AI, NewAllocaAddress, AI->getNextNode(), Builder,
|
||||
Deref, Offset);
|
||||
}
|
||||
|
||||
/// changeToUnreachable - Insert an unreachable instruction before the specified
|
||||
/// instruction, making it and the rest of the code in the block dead.
|
||||
static void changeToUnreachable(Instruction *I, bool UseLLVMTrap) {
|
||||
|
||||
51
test/Transforms/SafeStack/byval.ll
Normal file
51
test/Transforms/SafeStack/byval.ll
Normal file
@ -0,0 +1,51 @@
|
||||
; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
|
||||
; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
|
||||
|
||||
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
|
||||
target triple = "x86_64-unknown-linux-gnu"
|
||||
|
||||
%struct.S = type { [100 x i32] }
|
||||
|
||||
; Safe access to a byval argument.
|
||||
define i32 @ByValSafe(%struct.S* byval nocapture readonly align 8 %zzz) norecurse nounwind readonly safestack uwtable {
|
||||
entry:
|
||||
; CHECK-LABEL: @ByValSafe
|
||||
; CHECK-NOT: __safestack_unsafe_stack_ptr
|
||||
; CHECK: ret i32
|
||||
%arrayidx = getelementptr inbounds %struct.S, %struct.S* %zzz, i64 0, i32 0, i64 3
|
||||
%0 = load i32, i32* %arrayidx, align 4
|
||||
ret i32 %0
|
||||
}
|
||||
|
||||
; Unsafe access to a byval argument.
|
||||
; Argument is copied to the unsafe stack.
|
||||
define i32 @ByValUnsafe(%struct.S* byval nocapture readonly align 8 %zzz, i64 %idx) norecurse nounwind readonly safestack uwtable {
|
||||
entry:
|
||||
; CHECK-LABEL: @ByValUnsafe
|
||||
; CHECK: %[[A:.*]] = load {{.*}} @__safestack_unsafe_stack_ptr
|
||||
; CHECK: store {{.*}} @__safestack_unsafe_stack_ptr
|
||||
; CHECK: %[[B:.*]] = getelementptr i8, i8* %[[A]], i32 -400
|
||||
; CHECK: %[[C:.*]] = bitcast %struct.S* %zzz to i8*
|
||||
; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %[[B]], i8* %[[C]], i64 400, i32 8, i1 false)
|
||||
; CHECK: ret i32
|
||||
%arrayidx = getelementptr inbounds %struct.S, %struct.S* %zzz, i64 0, i32 0, i64 %idx
|
||||
%0 = load i32, i32* %arrayidx, align 4
|
||||
ret i32 %0
|
||||
}
|
||||
|
||||
; Highly aligned byval argument.
|
||||
define i32 @ByValUnsafeAligned(%struct.S* byval nocapture readonly align 64 %zzz, i64 %idx) norecurse nounwind readonly safestack uwtable {
|
||||
entry:
|
||||
; CHECK-LABEL: @ByValUnsafeAligned
|
||||
; CHECK: %[[A:.*]] = load {{.*}} @__safestack_unsafe_stack_ptr
|
||||
; CHECK: %[[B:.*]] = ptrtoint i8* %[[A]] to i64
|
||||
; CHECK: and i64 %[[B]], -64
|
||||
; CHECK: ret i32
|
||||
%arrayidx = getelementptr inbounds %struct.S, %struct.S* %zzz, i64 0, i32 0, i64 0
|
||||
%0 = load i32, i32* %arrayidx, align 64
|
||||
%arrayidx2 = getelementptr inbounds %struct.S, %struct.S* %zzz, i64 0, i32 0, i64 %idx
|
||||
%1 = load i32, i32* %arrayidx2, align 4
|
||||
%add = add nsw i32 %1, %0
|
||||
ret i32 %add
|
||||
}
|
||||
|
||||
@ -1,83 +1,83 @@
|
||||
; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
|
||||
|
||||
; Test debug location for the local variables moved onto the unsafe stack.
|
||||
; CHECK: define void @f
|
||||
; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
|
||||
|
||||
; dbg.declare for %buf is gone; replaced with dbg.declare based off the unsafe stack pointer
|
||||
; CHECK-NOT: @llvm.dbg.declare.*%buf
|
||||
; CHECK: call void @llvm.dbg.declare(metadata i8* %[[USP]], metadata ![[VAR:.*]], metadata ![[EXPR:.*]])
|
||||
|
||||
; dbg.declare appears before the first use of %buf
|
||||
; CHECK: getelementptr{{.*}}%buf
|
||||
; CHECK: call{{.*}}@Capture
|
||||
; CHECK: ret void
|
||||
|
||||
; dbg.declare describes "buf"...
|
||||
; CHECK: ![[VAR]] = !DILocalVariable(name: "buf"
|
||||
|
||||
; ... as an offset from the unsafe stack pointer
|
||||
; CHECK: ![[EXPR]] = !DIExpression(DW_OP_deref, DW_OP_minus, 400)
|
||||
|
||||
|
||||
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
|
||||
target triple = "x86_64-unknown-linux-gnu"
|
||||
|
||||
%struct.S = type { [100 x i8] }
|
||||
|
||||
; Function Attrs: safestack uwtable
|
||||
define void @f() #0 !dbg !4 {
|
||||
define void @f(%struct.S* byval align 8 %zzz) #0 !dbg !12 {
|
||||
; CHECK: define void @f
|
||||
|
||||
entry:
|
||||
%buf = alloca [100 x i32], align 16
|
||||
%0 = bitcast [100 x i32]* %buf to i8*, !dbg !16
|
||||
call void @llvm.lifetime.start(i64 400, i8* %0) #4, !dbg !16
|
||||
tail call void @llvm.dbg.declare(metadata [100 x i32]* %buf, metadata !8, metadata !17), !dbg !18
|
||||
; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
|
||||
|
||||
%xxx = alloca %struct.S, align 1
|
||||
call void @llvm.dbg.declare(metadata %struct.S* %zzz, metadata !18, metadata !19), !dbg !20
|
||||
call void @llvm.dbg.declare(metadata %struct.S* %xxx, metadata !21, metadata !19), !dbg !22
|
||||
|
||||
%arraydecay = getelementptr inbounds [100 x i32], [100 x i32]* %buf, i64 0, i64 0, !dbg !19
|
||||
call void @Capture(i32* %arraydecay), !dbg !20
|
||||
call void @llvm.lifetime.end(i64 400, i8* %0) #4, !dbg !21
|
||||
ret void, !dbg !21
|
||||
; dbg.declare for %zzz and %xxx are gone; replaced with dbg.declare based off the unsafe stack pointer
|
||||
; CHECK-NOT: call void @llvm.dbg.declare
|
||||
; CHECK: call void @llvm.dbg.declare(metadata i8* %[[USP]], metadata ![[VAR_ARG:.*]], metadata ![[EXPR_ARG:.*]])
|
||||
; CHECK-NOT: call void @llvm.dbg.declare
|
||||
; CHECK: call void @llvm.dbg.declare(metadata i8* %[[USP]], metadata ![[VAR_LOCAL:.*]], metadata ![[EXPR_LOCAL:.*]])
|
||||
; CHECK-NOT: call void @llvm.dbg.declare
|
||||
|
||||
call void @Capture(%struct.S* %zzz), !dbg !23
|
||||
call void @Capture(%struct.S* %xxx), !dbg !24
|
||||
|
||||
; dbg.declare appears before the first use
|
||||
; CHECK: call void @Capture
|
||||
; CHECK: call void @Capture
|
||||
|
||||
ret void, !dbg !25
|
||||
}
|
||||
|
||||
; Function Attrs: nounwind argmemonly
|
||||
declare void @llvm.lifetime.start(i64, i8* nocapture) #1
|
||||
; CHECK-DAG: ![[VAR_ARG]] = !DILocalVariable(name: "zzz"
|
||||
; 100 aligned up to 8
|
||||
; CHECK-DAG: ![[EXPR_ARG]] = !DIExpression(DW_OP_deref, DW_OP_minus, 104
|
||||
|
||||
; CHECK-DAG: ![[VAR_LOCAL]] = !DILocalVariable(name: "xxx"
|
||||
; CHECK-DAG: ![[EXPR_LOCAL]] = !DIExpression(DW_OP_deref, DW_OP_minus, 208
|
||||
|
||||
; Function Attrs: nounwind readnone
|
||||
declare void @llvm.dbg.declare(metadata, metadata, metadata) #2
|
||||
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
|
||||
|
||||
declare void @Capture(i32*) #3
|
||||
declare void @Capture(%struct.S*) #2
|
||||
|
||||
; Function Attrs: nounwind argmemonly
|
||||
declare void @llvm.lifetime.end(i64, i8* nocapture) #1
|
||||
|
||||
attributes #0 = { safestack uwtable "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
||||
attributes #1 = { nounwind argmemonly }
|
||||
attributes #2 = { nounwind readnone }
|
||||
attributes #3 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
||||
attributes #4 = { nounwind }
|
||||
attributes #0 = { safestack uwtable "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
||||
attributes #1 = { nounwind readnone }
|
||||
attributes #2 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
|
||||
|
||||
!llvm.dbg.cu = !{!0}
|
||||
!llvm.module.flags = !{!13, !14}
|
||||
!llvm.ident = !{!15}
|
||||
!llvm.module.flags = !{!15, !16}
|
||||
!llvm.ident = !{!17}
|
||||
|
||||
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3)
|
||||
!1 = !DIFile(filename: "1.cc", directory: "/tmp")
|
||||
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 254019) (llvm/trunk 254036)", isOptimized: false, runtimeVersion: 0, emissionKind: 1, enums: !2, retainedTypes: !3, subprograms: !11)
|
||||
!1 = !DIFile(filename: "../llvm/2.cc", directory: "/code/build-llvm")
|
||||
!2 = !{}
|
||||
!3 = !{!4}
|
||||
!4 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 4, type: !5, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, variables: !7)
|
||||
!5 = !DISubroutineType(types: !6)
|
||||
!6 = !{null}
|
||||
!7 = !{!8}
|
||||
!8 = !DILocalVariable(name: "buf", scope: !4, file: !1, line: 5, type: !9)
|
||||
!9 = !DICompositeType(tag: DW_TAG_array_type, baseType: !10, size: 3200, align: 32, elements: !11)
|
||||
!10 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
|
||||
!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "S", file: !1, line: 4, size: 800, align: 8, elements: !5, identifier: "_ZTS1S")
|
||||
!5 = !{!6}
|
||||
!6 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !"_ZTS1S", file: !1, line: 5, baseType: !7, size: 800, align: 8)
|
||||
!7 = !DICompositeType(tag: DW_TAG_array_type, baseType: !8, size: 800, align: 8, elements: !9)
|
||||
!8 = !DIBasicType(name: "char", size: 8, align: 8, encoding: DW_ATE_signed_char)
|
||||
!9 = !{!10}
|
||||
!10 = !DISubrange(count: 100)
|
||||
!11 = !{!12}
|
||||
!12 = !DISubrange(count: 100)
|
||||
!13 = !{i32 2, !"Dwarf Version", i32 4}
|
||||
!14 = !{i32 2, !"Debug Info Version", i32 3}
|
||||
!15 = !{!"clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)"}
|
||||
!16 = !DILocation(line: 5, column: 3, scope: !4)
|
||||
!17 = !DIExpression()
|
||||
!18 = !DILocation(line: 5, column: 7, scope: !4)
|
||||
!19 = !DILocation(line: 6, column: 11, scope: !4)
|
||||
!20 = !DILocation(line: 6, column: 3, scope: !4)
|
||||
!21 = !DILocation(line: 7, column: 1, scope: !4)
|
||||
!12 = distinct !DISubprogram(name: "f", linkageName: "_Z1f1S", scope: !1, file: !1, line: 10, type: !13, isLocal: false, isDefinition: true, scopeLine: 10, flags: DIFlagPrototyped, isOptimized: false, variables: !2)
|
||||
!13 = !DISubroutineType(types: !14)
|
||||
!14 = !{null, !"_ZTS1S"}
|
||||
!15 = !{i32 2, !"Dwarf Version", i32 4}
|
||||
!16 = !{i32 2, !"Debug Info Version", i32 3}
|
||||
!17 = !{!"clang version 3.8.0 (trunk 254019) (llvm/trunk 254036)"}
|
||||
!18 = !DILocalVariable(name: "zzz", arg: 1, scope: !12, file: !1, line: 10, type: !"_ZTS1S")
|
||||
!19 = !DIExpression()
|
||||
!20 = !DILocation(line: 10, column: 10, scope: !12)
|
||||
!21 = !DILocalVariable(name: "xxx", scope: !12, file: !1, line: 11, type: !"_ZTS1S")
|
||||
!22 = !DILocation(line: 11, column: 5, scope: !12)
|
||||
!23 = !DILocation(line: 12, column: 3, scope: !12)
|
||||
!24 = !DILocation(line: 13, column: 3, scope: !12)
|
||||
!25 = !DILocation(line: 14, column: 1, scope: !12)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user