1 //===- ASanStackFrameLayout.h - ComputeASanStackFrameLayout -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header defines ComputeASanStackFrameLayout and auxiliary data structs.
12 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H
14 #define LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H
15 #include "llvm/ADT/SmallString.h"
16 #include "llvm/ADT/SmallVector.h"
22 // These magic constants should be the same as in
23 // in asan_internal.h from ASan runtime in compiler-rt.
24 static const int kAsanStackLeftRedzoneMagic = 0xf1;
25 static const int kAsanStackMidRedzoneMagic = 0xf2;
26 static const int kAsanStackRightRedzoneMagic = 0xf3;
28 // Input/output data struct for ComputeASanStackFrameLayout.
29 struct ASanStackVariableDescription {
30 const char *Name; // Name of the variable that will be displayed by asan
31 // if a stack-related bug is reported.
32 uint64_t Size; // Size of the variable in bytes.
33 size_t Alignment; // Alignment of the variable (power of 2).
34 AllocaInst *AI; // The actual AllocaInst.
35 size_t Offset; // Offset from the beginning of the frame;
36 // set by ComputeASanStackFrameLayout.
39 // Output data struct for ComputeASanStackFrameLayout.
40 struct ASanStackFrameLayout {
41 // Frame description, see DescribeAddressIfStack in ASan runtime.
42 SmallString<64> DescriptionString;
43 // The contents of the shadow memory for the stack frame that we need
44 // to set at function entry.
45 SmallVector<uint8_t, 64> ShadowBytes;
46 size_t FrameAlignment; // Alignment for the entire frame.
47 size_t FrameSize; // Size of the frame in bytes.
50 void ComputeASanStackFrameLayout(
51 // The array of stack variables. The elements may get reordered and changed.
52 SmallVectorImpl<ASanStackVariableDescription> &Vars,
53 // AddressSanitizer's shadow granularity. Usually 8, may also be 16, 32, 64.
55 // The minimal size of the left-most redzone (header).
56 // At least 4 pointer sizes, power of 2, and >= Granularity.
57 // The resulting FrameSize should be multiple of MinHeaderSize.
59 // The result is put here.
60 ASanStackFrameLayout *Layout);
64 #endif // LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H