Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- ASanStackFrameLayout.h - ComputeASanStackFrameLayout -----*- 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

//

//===----------------------------------------------------------------------===//

//

// This header defines ComputeASanStackFrameLayout and auxiliary data structs.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H

#define LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H

#include "llvm/ADT/SmallString.h"

#include "llvm/ADT/SmallVector.h"

namespace llvm {

class AllocaInst;

// These magic constants should be the same as in

// in asan_internal.h from ASan runtime in compiler-rt.

static const int kAsanStackLeftRedzoneMagic = 0xf1;

static const int kAsanStackMidRedzoneMagic = 0xf2;

static const int kAsanStackRightRedzoneMagic = 0xf3;

static const int kAsanStackUseAfterReturnMagic = 0xf5;

static const int kAsanStackUseAfterScopeMagic = 0xf8;

// Input/output data struct for ComputeASanStackFrameLayout.

struct ASanStackVariableDescription {

  const char *Name;    // Name of the variable that will be displayed by asan

                       // if a stack-related bug is reported.

  uint64_t Size;       // Size of the variable in bytes.

  size_t LifetimeSize; // Size in bytes to use for lifetime analysis check.

                       // Will be rounded up to Granularity.

  uint64_t Alignment;  // Alignment of the variable (power of 2).

  AllocaInst *AI;      // The actual AllocaInst.

  size_t Offset;       // Offset from the beginning of the frame;

                       // set by ComputeASanStackFrameLayout.

  unsigned Line;       // Line number.

};

// Output data struct for ComputeASanStackFrameLayout.

struct ASanStackFrameLayout {

  uint64_t Granularity;     // Shadow granularity.

  uint64_t FrameAlignment;  // Alignment for the entire frame.

  uint64_t FrameSize;       // Size of the frame in bytes.

};

ASanStackFrameLayout ComputeASanStackFrameLayout(

    // The array of stack variables. The elements may get reordered and changed.

    SmallVectorImpl<ASanStackVariableDescription> &Vars,

    // AddressSanitizer's shadow granularity. Usually 8, may also be 16, 32, 64.

    uint64_t Granularity,

    // The minimal size of the left-most redzone (header).

    // At least 4 pointer sizes, power of 2, and >= Granularity.

    // The resulting FrameSize should be multiple of MinHeaderSize.

    uint64_t MinHeaderSize);

// Compute frame description, see DescribeAddressIfStack in ASan runtime.

SmallString<64> ComputeASanStackFrameDescription(

    const SmallVectorImpl<ASanStackVariableDescription> &Vars);

// Returns shadow bytes with marked red zones. This shadow represents the state

// if the stack frame when all local variables are inside of the own scope.

SmallVector<uint8_t, 64>

GetShadowBytes(const SmallVectorImpl<ASanStackVariableDescription> &Vars,

               const ASanStackFrameLayout &Layout);

// Returns shadow bytes with marked red zones and after scope. This shadow

// represents the state if the stack frame when all local variables are outside

// of the own scope.

SmallVector<uint8_t, 64> GetShadowBytesAfterScope(

    // The array of stack variables. The elements may get reordered and changed.

    const SmallVectorImpl<ASanStackVariableDescription> &Vars,

    const ASanStackFrameLayout &Layout);

} // llvm namespace

#endif  // LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H