LLVM  6.0.0svn
ASanStackFrameLayout.h
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1 //===- ASanStackFrameLayout.h - ComputeASanStackFrameLayout -----*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This header defines ComputeASanStackFrameLayout and auxiliary data structs.
11 //
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"
17 
18 namespace llvm {
19 
20 class AllocaInst;
21 
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;
27 static const int kAsanStackUseAfterReturnMagic = 0xf5;
28 static const int kAsanStackUseAfterScopeMagic = 0xf8;
29 
30 // Input/output data struct for ComputeASanStackFrameLayout.
32  const char *Name; // Name of the variable that will be displayed by asan
33  // if a stack-related bug is reported.
34  uint64_t Size; // Size of the variable in bytes.
35  size_t LifetimeSize; // Size in bytes to use for lifetime analysis check.
36  // Will be rounded up to Granularity.
37  size_t Alignment; // Alignment of the variable (power of 2).
38  AllocaInst *AI; // The actual AllocaInst.
39  size_t Offset; // Offset from the beginning of the frame;
40  // set by ComputeASanStackFrameLayout.
41  unsigned Line; // Line number.
42 };
43 
44 // Output data struct for ComputeASanStackFrameLayout.
46  size_t Granularity; // Shadow granularity.
47  size_t FrameAlignment; // Alignment for the entire frame.
48  size_t FrameSize; // Size of the frame in bytes.
49 };
50 
52  // The array of stack variables. The elements may get reordered and changed.
54  // AddressSanitizer's shadow granularity. Usually 8, may also be 16, 32, 64.
55  size_t Granularity,
56  // The minimal size of the left-most redzone (header).
57  // At least 4 pointer sizes, power of 2, and >= Granularity.
58  // The resulting FrameSize should be multiple of MinHeaderSize.
59  size_t MinHeaderSize);
60 
61 // Compute frame description, see DescribeAddressIfStack in ASan runtime.
64 
65 // Returns shadow bytes with marked red zones. This shadow represents the state
66 // if the stack frame when all local variables are inside of the own scope.
69  const ASanStackFrameLayout &Layout);
70 
71 // Returns shadow bytes with marked red zones and after scope. This shadow
72 // represents the state if the stack frame when all local variables are outside
73 // of the own scope.
75  // The array of stack variables. The elements may get reordered and changed.
77  const ASanStackFrameLayout &Layout);
78 
79 } // llvm namespace
80 
81 #endif // LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
static const int kAsanStackMidRedzoneMagic
SmallString< 64 > ComputeASanStackFrameDescription(const SmallVectorImpl< ASanStackVariableDescription > &Vars)
static const int kAsanStackLeftRedzoneMagic
static const int kAsanStackUseAfterReturnMagic
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:42
SmallVector< uint8_t, 64 > GetShadowBytesAfterScope(const SmallVectorImpl< ASanStackVariableDescription > &Vars, const ASanStackFrameLayout &Layout)
static const int kAsanStackRightRedzoneMagic
ASanStackFrameLayout ComputeASanStackFrameLayout(SmallVectorImpl< ASanStackVariableDescription > &Vars, size_t Granularity, size_t MinHeaderSize)
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:864
static const int kAsanStackUseAfterScopeMagic
an instruction to allocate memory on the stack
Definition: Instructions.h:60
SmallVector< uint8_t, 64 > GetShadowBytes(const SmallVectorImpl< ASanStackVariableDescription > &Vars, const ASanStackFrameLayout &Layout)