/// an alloca, if any.
DbgDeclareInst *FindAllocaDbgDeclare(Value *V);
-/// \brief Replaces llvm.dbg.declare instruction when an alloca is replaced with
-/// a new value. If Deref is true, an additional DW_OP_deref is prepended to the
-/// expression. If Offset is non-zero, a constant displacement is added to the
-/// expression (after the optional Deref). Offset can be negative.
+/// \brief Replaces llvm.dbg.declare instruction when the address it describes
+/// is replaced with a new value. If Deref is true, an additional DW_OP_deref is
+/// prepended to the expression. If Offset is non-zero, a constant displacement
+/// is added to the expression (after the optional Deref). Offset can be
+/// negative.
+bool replaceDbgDeclare(Value *Address, Value *NewAddress,
+ Instruction *InsertBefore, DIBuilder &Builder,
+ bool Deref, int Offset);
+
+/// \brief Replaces llvm.dbg.declare instruction when the alloca it describes
+/// is replaced with a new value. If Deref is true, an additional DW_OP_deref is
+/// prepended to the expression. If Offset is non-zero, a constant displacement
+/// is added to the expression (after the optional Deref). Offset can be
+/// negative. New llvm.dbg.declare is inserted immediately before AI.
bool replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
DIBuilder &Builder, bool Deref, int Offset = 0);
STATISTIC(NumAllocas, "Total number of allocas");
STATISTIC(NumUnsafeStaticAllocas, "Number of unsafe static allocas");
STATISTIC(NumUnsafeDynamicAllocas, "Number of unsafe dynamic allocas");
+STATISTIC(NumUnsafeByValArguments, "Number of unsafe byval arguments");
STATISTIC(NumUnsafeStackRestorePoints, "Number of setjmps and landingpads");
} // namespace llvm
///
/// The implementation simply replaces all mentions of the alloca with zero.
class AllocaOffsetRewriter : public SCEVRewriteVisitor<AllocaOffsetRewriter> {
- const AllocaInst *AI;
+ const Value *AllocaPtr;
public:
- AllocaOffsetRewriter(ScalarEvolution &SE, const AllocaInst *AI)
- : SCEVRewriteVisitor(SE), AI(AI) {}
+ AllocaOffsetRewriter(ScalarEvolution &SE, const Value *AllocaPtr)
+ : SCEVRewriteVisitor(SE), AllocaPtr(AllocaPtr) {}
const SCEV *visitUnknown(const SCEVUnknown *Expr) {
- if (Expr->getValue() == AI)
+ if (Expr->getValue() == AllocaPtr)
return SE.getZero(Expr->getType());
return Expr;
}
/// given function and append them to the respective vectors.
void findInsts(Function &F, SmallVectorImpl<AllocaInst *> &StaticAllocas,
SmallVectorImpl<AllocaInst *> &DynamicAllocas,
+ SmallVectorImpl<Argument *> &ByValArguments,
SmallVectorImpl<ReturnInst *> &Returns,
SmallVectorImpl<Instruction *> &StackRestorePoints);
/// allocas are allocated.
Value *moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
ArrayRef<AllocaInst *> StaticAllocas,
+ ArrayRef<Argument *> ByValArguments,
ArrayRef<ReturnInst *> Returns);
/// \brief Generate code to restore the stack after all stack restore points
AllocaInst *DynamicTop,
ArrayRef<AllocaInst *> DynamicAllocas);
- bool IsSafeStackAlloca(const AllocaInst *AI);
+ bool IsSafeStackAlloca(const Value *AllocaPtr, uint64_t AllocaSize);
bool IsMemIntrinsicSafe(const MemIntrinsic *MI, const Use &U,
- const AllocaInst *AI);
- bool IsAccessSafe(Value *Addr, uint64_t Size, const AllocaInst *AI);
+ const Value *AllocaPtr, uint64_t AllocaSize);
+ bool IsAccessSafe(Value *Addr, uint64_t Size, const Value *AllocaPtr,
+ uint64_t AllocaSize);
public:
static char ID; // Pass identification, replacement for typeid.
return Size;
}
-bool SafeStack::IsAccessSafe(Value *Addr, uint64_t Size, const AllocaInst *AI) {
- AllocaOffsetRewriter Rewriter(*SE, AI);
+bool SafeStack::IsAccessSafe(Value *Addr, uint64_t AccessSize,
+ const Value *AllocaPtr, uint64_t AllocaSize) {
+ AllocaOffsetRewriter Rewriter(*SE, AllocaPtr);
const SCEV *Expr = Rewriter.visit(SE->getSCEV(Addr));
uint64_t BitWidth = SE->getTypeSizeInBits(Expr->getType());
ConstantRange AccessStartRange = SE->getUnsignedRange(Expr);
ConstantRange SizeRange =
- ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, Size));
+ ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, AccessSize));
ConstantRange AccessRange = AccessStartRange.add(SizeRange);
- ConstantRange AllocaRange = ConstantRange(
- APInt(BitWidth, 0), APInt(BitWidth, getStaticAllocaAllocationSize(AI)));
+ ConstantRange AllocaRange =
+ ConstantRange(APInt(BitWidth, 0), APInt(BitWidth, AllocaSize));
bool Safe = AllocaRange.contains(AccessRange);
- DEBUG(dbgs() << "[SafeStack] Alloca " << *AI << "\n"
+ DEBUG(dbgs() << "[SafeStack] "
+ << (isa<AllocaInst>(AllocaPtr) ? "Alloca " : "ByValArgument ")
+ << *AllocaPtr << "\n"
<< " Access " << *Addr << "\n"
<< " SCEV " << *Expr
<< " U: " << SE->getUnsignedRange(Expr)
}
bool SafeStack::IsMemIntrinsicSafe(const MemIntrinsic *MI, const Use &U,
- const AllocaInst *AI) {
+ const Value *AllocaPtr,
+ uint64_t AllocaSize) {
// All MemIntrinsics have destination address in Arg0 and size in Arg2.
if (MI->getRawDest() != U) return true;
const auto *Len = dyn_cast<ConstantInt>(MI->getLength());
// Non-constant size => unsafe. FIXME: try SCEV getRange.
if (!Len) return false;
- return IsAccessSafe(U, Len->getZExtValue(), AI);
+ return IsAccessSafe(U, Len->getZExtValue(), AllocaPtr, AllocaSize);
}
-/// Check whether a given alloca instruction (AI) should be put on the safe
+/// Check whether a given allocation must be put on the safe
/// stack or not. The function analyzes all uses of AI and checks whether it is
/// only accessed in a memory safe way (as decided statically).
-bool SafeStack::IsSafeStackAlloca(const AllocaInst *AI) {
+bool SafeStack::IsSafeStackAlloca(const Value *AllocaPtr, uint64_t AllocaSize) {
// Go through all uses of this alloca and check whether all accesses to the
// allocated object are statically known to be memory safe and, hence, the
// object can be placed on the safe stack.
SmallPtrSet<const Value *, 16> Visited;
- SmallVector<const Instruction *, 8> WorkList;
- WorkList.push_back(AI);
+ SmallVector<const Value *, 8> WorkList;
+ WorkList.push_back(AllocaPtr);
// A DFS search through all uses of the alloca in bitcasts/PHI/GEPs/etc.
while (!WorkList.empty()) {
- const Instruction *V = WorkList.pop_back_val();
+ const Value *V = WorkList.pop_back_val();
for (const Use &UI : V->uses()) {
auto I = cast<const Instruction>(UI.getUser());
assert(V == UI.get());
switch (I->getOpcode()) {
case Instruction::Load: {
- if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getType()), AI))
+ if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getType()), AllocaPtr,
+ AllocaSize))
return false;
break;
}
case Instruction::Store: {
if (V == I->getOperand(0)) {
// Stored the pointer - conservatively assume it may be unsafe.
- DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
+ DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
<< "\n store of address: " << *I << "\n");
return false;
}
- if (!IsAccessSafe(
- UI, DL->getTypeStoreSize(I->getOperand(0)->getType()), AI))
+ if (!IsAccessSafe(UI, DL->getTypeStoreSize(I->getOperand(0)->getType()),
+ AllocaPtr, AllocaSize))
return false;
break;
}
}
if (const MemIntrinsic *MI = dyn_cast<MemIntrinsic>(I)) {
- if (!IsMemIntrinsicSafe(MI, UI, AI)) {
- DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
+ if (!IsMemIntrinsicSafe(MI, UI, AllocaPtr, AllocaSize)) {
+ DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
<< "\n unsafe memintrinsic: " << *I
<< "\n");
return false;
ImmutableCallSite::arg_iterator B = CS.arg_begin(), E = CS.arg_end();
for (ImmutableCallSite::arg_iterator A = B; A != E; ++A)
if (A->get() == V)
- if (!(CS.doesNotCapture(A - B) &&
- (CS.doesNotAccessMemory(A - B) || CS.doesNotAccessMemory()))) {
- DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AI
+ if (!(CS.doesNotCapture(A - B) && (CS.doesNotAccessMemory(A - B) ||
+ CS.doesNotAccessMemory()))) {
+ DEBUG(dbgs() << "[SafeStack] Unsafe alloca: " << *AllocaPtr
<< "\n unsafe call: " << *I << "\n");
return false;
}
void SafeStack::findInsts(Function &F,
SmallVectorImpl<AllocaInst *> &StaticAllocas,
SmallVectorImpl<AllocaInst *> &DynamicAllocas,
+ SmallVectorImpl<Argument *> &ByValArguments,
SmallVectorImpl<ReturnInst *> &Returns,
SmallVectorImpl<Instruction *> &StackRestorePoints) {
for (Instruction &I : instructions(&F)) {
if (auto AI = dyn_cast<AllocaInst>(&I)) {
++NumAllocas;
- if (IsSafeStackAlloca(AI))
+ uint64_t Size = getStaticAllocaAllocationSize(AI);
+ if (IsSafeStackAlloca(AI, Size))
continue;
if (AI->isStaticAlloca()) {
"gcroot intrinsic not compatible with safestack attribute");
}
}
+ for (Argument &Arg : F.args()) {
+ if (!Arg.hasByValAttr())
+ continue;
+ uint64_t Size =
+ DL->getTypeStoreSize(Arg.getType()->getPointerElementType());
+ if (IsSafeStackAlloca(&Arg, Size))
+ continue;
+
+ ++NumUnsafeByValArguments;
+ ByValArguments.push_back(&Arg);
+ }
}
AllocaInst *
for (Instruction *I : StackRestorePoints) {
++NumUnsafeStackRestorePoints;
- IRB.SetInsertPoint(cast<Instruction>(I->getNextNode()));
+ IRB.SetInsertPoint(I->getNextNode());
Value *CurrentTop = DynamicTop ? IRB.CreateLoad(DynamicTop) : StaticTop;
IRB.CreateStore(CurrentTop, UnsafeStackPtr);
}
return DynamicTop;
}
-Value *
-SafeStack::moveStaticAllocasToUnsafeStack(IRBuilder<> &IRB, Function &F,
- ArrayRef<AllocaInst *> StaticAllocas,
- ArrayRef<ReturnInst *> Returns) {
- if (StaticAllocas.empty())
+Value *SafeStack::moveStaticAllocasToUnsafeStack(
+ IRBuilder<> &IRB, Function &F, ArrayRef<AllocaInst *> StaticAllocas,
+ ArrayRef<Argument *> ByValArguments, ArrayRef<ReturnInst *> Returns) {
+ if (StaticAllocas.empty() && ByValArguments.empty())
return nullptr;
DIBuilder DIB(*F.getParent());
// Compute maximum alignment among static objects on the unsafe stack.
unsigned MaxAlignment = 0;
+ for (Argument *Arg : ByValArguments) {
+ Type *Ty = Arg->getType()->getPointerElementType();
+ unsigned Align = std::max((unsigned)DL->getPrefTypeAlignment(Ty),
+ Arg->getParamAlignment());
+ if (Align > MaxAlignment)
+ MaxAlignment = Align;
+ }
for (AllocaInst *AI : StaticAllocas) {
Type *Ty = AI->getAllocatedType();
unsigned Align =
if (MaxAlignment > StackAlignment) {
// Re-align the base pointer according to the max requested alignment.
assert(isPowerOf2_32(MaxAlignment));
- IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
+ IRB.SetInsertPoint(BasePointer->getNextNode());
BasePointer = cast<Instruction>(IRB.CreateIntToPtr(
IRB.CreateAnd(IRB.CreatePtrToInt(BasePointer, IntPtrTy),
ConstantInt::get(IntPtrTy, ~uint64_t(MaxAlignment - 1))),
StackPtrTy));
}
- // Allocate space for every unsafe static AllocaInst on the unsafe stack.
int64_t StaticOffset = 0; // Current stack top.
+ IRB.SetInsertPoint(BasePointer->getNextNode());
+
+ for (Argument *Arg : ByValArguments) {
+ Type *Ty = Arg->getType()->getPointerElementType();
+
+ uint64_t Size = DL->getTypeStoreSize(Ty);
+ if (Size == 0)
+ Size = 1; // Don't create zero-sized stack objects.
+
+ // Ensure the object is properly aligned.
+ unsigned Align = std::max((unsigned)DL->getPrefTypeAlignment(Ty),
+ Arg->getParamAlignment());
+
+ // Add alignment.
+ // NOTE: we ensure that BasePointer itself is aligned to >= Align.
+ StaticOffset += Size;
+ StaticOffset = RoundUpToAlignment(StaticOffset, Align);
+
+ Value *Off = IRB.CreateGEP(BasePointer, // BasePointer is i8*
+ ConstantInt::get(Int32Ty, -StaticOffset));
+ Value *NewArg = IRB.CreateBitCast(Off, Arg->getType(),
+ Arg->getName() + ".unsafe-byval");
+
+ // Replace alloc with the new location.
+ replaceDbgDeclare(Arg, BasePointer, BasePointer->getNextNode(), DIB,
+ /*Deref=*/true, -StaticOffset);
+ Arg->replaceAllUsesWith(NewArg);
+ IRB.SetInsertPoint(cast<Instruction>(NewArg)->getNextNode());
+ IRB.CreateMemCpy(Off, Arg, Size, Arg->getParamAlignment());
+ }
+
+ // Allocate space for every unsafe static AllocaInst on the unsafe stack.
for (AllocaInst *AI : StaticAllocas) {
IRB.SetInsertPoint(AI);
StaticOffset = RoundUpToAlignment(StaticOffset, StackAlignment);
// Update shadow stack pointer in the function epilogue.
- IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
+ IRB.SetInsertPoint(BasePointer->getNextNode());
Value *StaticTop =
IRB.CreateGEP(BasePointer, ConstantInt::get(Int32Ty, -StaticOffset),
SmallVector<AllocaInst *, 16> StaticAllocas;
SmallVector<AllocaInst *, 4> DynamicAllocas;
+ SmallVector<Argument *, 4> ByValArguments;
SmallVector<ReturnInst *, 4> Returns;
// Collect all points where stack gets unwound and needs to be restored
// Find all static and dynamic alloca instructions that must be moved to the
// unsafe stack, all return instructions and stack restore points.
- findInsts(F, StaticAllocas, DynamicAllocas, Returns, StackRestorePoints);
+ findInsts(F, StaticAllocas, DynamicAllocas, ByValArguments, Returns,
+ StackRestorePoints);
if (StaticAllocas.empty() && DynamicAllocas.empty() &&
- StackRestorePoints.empty())
+ ByValArguments.empty() && StackRestorePoints.empty())
return false; // Nothing to do in this function.
- if (!StaticAllocas.empty() || !DynamicAllocas.empty())
+ if (!StaticAllocas.empty() || !DynamicAllocas.empty() ||
+ !ByValArguments.empty())
++NumUnsafeStackFunctions; // This function has the unsafe stack.
if (!StackRestorePoints.empty())
UnsafeStackPtr = getOrCreateUnsafeStackPtr(IRB, F);
// The top of the unsafe stack after all unsafe static allocas are allocated.
- Value *StaticTop = moveStaticAllocasToUnsafeStack(IRB, F, StaticAllocas, Returns);
+ Value *StaticTop = moveStaticAllocasToUnsafeStack(IRB, F, StaticAllocas,
+ ByValArguments, Returns);
// Safe stack object that stores the current unsafe stack top. It is updated
// as unsafe dynamic (non-constant-sized) allocas are allocated and freed.
return nullptr;
}
-bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
- DIBuilder &Builder, bool Deref, int Offset) {
- DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI);
+bool llvm::replaceDbgDeclare(Value *Address, Value *NewAddress,
+ Instruction *InsertBefore, DIBuilder &Builder,
+ bool Deref, int Offset) {
+ DbgDeclareInst *DDI = FindAllocaDbgDeclare(Address);
if (!DDI)
return false;
DebugLoc Loc = DDI->getDebugLoc();
// 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) {
--- /dev/null
+; 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
+}
+
; 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:.*]])
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
-; dbg.declare appears before the first use of %buf
-; CHECK: getelementptr{{.*}}%buf
-; CHECK: call{{.*}}@Capture
-; CHECK: ret void
+%struct.S = type { [100 x i8] }
-; dbg.declare describes "buf"...
-; CHECK: ![[VAR]] = !DILocalVariable(name: "buf"
+; Function Attrs: safestack uwtable
+define void @f(%struct.S* byval align 8 %zzz) #0 !dbg !12 {
+; CHECK: define void @f
-; ... as an offset from the unsafe stack pointer
-; CHECK: ![[EXPR]] = !DIExpression(DW_OP_deref, DW_OP_minus, 400)
+entry:
+; 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
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
+; 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
-; Function Attrs: safestack uwtable
-define void @f() #0 !dbg !4 {
-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
+ 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
- %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
+ 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
-; Function Attrs: nounwind readnone
-declare void @llvm.dbg.declare(metadata, metadata, metadata) #2
+; CHECK-DAG: ![[VAR_LOCAL]] = !DILocalVariable(name: "xxx"
+; CHECK-DAG: ![[EXPR_LOCAL]] = !DIExpression(DW_OP_deref, DW_OP_minus, 208
-declare void @Capture(i32*) #3
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
-; Function Attrs: nounwind argmemonly
-declare void @llvm.lifetime.end(i64, i8* nocapture) #1
+declare void @Capture(%struct.S*) #2
-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)