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 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. 37 }; 38 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. 48 }; 49 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. 54 size_t Granularity, 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. 58 size_t MinHeaderSize, 59 // The result is put here. 60 ASanStackFrameLayout *Layout); 61 62 } // llvm namespace 63 64 #endif // LLVM_TRANSFORMS_UTILS_ASANSTACKFRAMELAYOUT_H 65
