libsanitizer/asan/asan_mapping_sparc64.h

   1 //===-- asan_mapping_sparc64.h ----------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a part of AddressSanitizer, an address sanity checker.
  10 //
  11 // SPARC64-specific definitions for ASan memory mapping.
  12 //===----------------------------------------------------------------------===//
  13 #ifndef ASAN_MAPPING_SPARC64_H
  14 #define ASAN_MAPPING_SPARC64_H
  15
  16 // This is tailored to the 52-bit VM layout on SPARC-T4 and later.
  17 // The VM space is split into two 51-bit halves at both ends: the low part
  18 // has all the bits above the 51st cleared, while the high part has them set.
  19 //   0xfff8000000000000 - 0xffffffffffffffff
  20 //   0x0000000000000000 - 0x0007ffffffffffff
  21
  22 #define VMA_BITS 52
  23 #define HIGH_BITS (64 - VMA_BITS)
  24
  25 // The idea is to chop the high bits before doing the scaling, so the two
  26 // parts become contiguous again and the usual scheme can be applied.
  27
  28 #define MEM_TO_SHADOW(mem)                                       \
  29   ((((mem) << HIGH_BITS) >> (HIGH_BITS + (ASAN_SHADOW_SCALE))) + \
  30    (ASAN_SHADOW_OFFSET))
  31 #define SHADOW_TO_MEM(ptr) (__asan::ShadowToMemSparc64(ptr))
  32
  33 #define kLowMemBeg 0
  34 #define kLowMemEnd (ASAN_SHADOW_OFFSET - 1)
  35
  36 #define kLowShadowBeg ASAN_SHADOW_OFFSET
  37 #define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd)
  38
  39 // But of course there is the huge hole between the high shadow memory,
  40 // which is in the low part, and the beginning of the high part.
  41
  42 #define kHighMemBeg (-(1ULL << (VMA_BITS - 1)))
  43
  44 #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg)
  45 #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd)
  46
  47 #define kMidShadowBeg 0
  48 #define kMidShadowEnd 0
  49
  50 // With the zero shadow base we can not actually map pages starting from 0.
  51 // This constant is somewhat arbitrary.
  52 #define kZeroBaseShadowStart 0
  53 #define kZeroBaseMaxShadowStart (1 << 18)
  54
  55 #define kShadowGapBeg (kLowShadowEnd + 1)
  56 #define kShadowGapEnd (kHighShadowBeg - 1)
  57
  58 #define kShadowGap2Beg 0
  59 #define kShadowGap2End 0
  60
  61 #define kShadowGap3Beg 0
  62 #define kShadowGap3End 0
  63
  64 namespace __asan {
  65
  66 static inline bool AddrIsInLowMem(uptr a) {
  67   PROFILE_ASAN_MAPPING();
  68   return a <= kLowMemEnd;
  69 }
  70
  71 static inline bool AddrIsInLowShadow(uptr a) {
  72   PROFILE_ASAN_MAPPING();
  73   return a >= kLowShadowBeg && a <= kLowShadowEnd;
  74 }
  75
  76 static inline bool AddrIsInMidMem(uptr a) {
  77   PROFILE_ASAN_MAPPING();
  78   return false;
  79 }
  80
  81 static inline bool AddrIsInMidShadow(uptr a) {
  82   PROFILE_ASAN_MAPPING();
  83   return false;
  84 }
  85
  86 static inline bool AddrIsInHighMem(uptr a) {
  87   PROFILE_ASAN_MAPPING();
  88   return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd;
  89 }
  90
  91 static inline bool AddrIsInHighShadow(uptr a) {
  92   PROFILE_ASAN_MAPPING();
  93   return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd;
  94 }
  95
  96 static inline bool AddrIsInShadowGap(uptr a) {
  97   PROFILE_ASAN_MAPPING();
  98   return a >= kShadowGapBeg && a <= kShadowGapEnd;
  99 }
 100
 101 static inline constexpr uptr ShadowToMemSparc64(uptr p) {
 102   PROFILE_ASAN_MAPPING();
 103   p -= ASAN_SHADOW_OFFSET;
 104   p <<= ASAN_SHADOW_SCALE;
 105   if (p >= 0x8000000000000) {
 106     p |= (~0ULL) << VMA_BITS;
 107   }
 108   return p;
 109 }
 110
 111 static_assert(ShadowToMemSparc64(MEM_TO_SHADOW(0x0000000000000000)) ==
 112               0x0000000000000000);
 113 static_assert(ShadowToMemSparc64(MEM_TO_SHADOW(0xfff8000000000000)) ==
 114               0xfff8000000000000);
 115 // Gets aligned down.
 116 static_assert(ShadowToMemSparc64(MEM_TO_SHADOW(0x0007ffffffffffff)) ==
 117               0x0007fffffffffff8);
 118
 119 }  // namespace __asan
 120
 121 #endif  // ASAN_MAPPING_SPARC64_H