1 files changed, 120 insertions, 0 deletions
diff --git a/libsanitizer/asan/asan_mapping.h b/libsanitizer/asan/asan_mapping.h
new file mode 100644
index 00000000000..40a38db0544
--- /dev/null
+++ b/libsanitizer/asan/asan_mapping.h
@@ -0,0 +1,120 @@
+//===-- asan_mapping.h ------------------------------------------*- C++ -*-===//
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Defines ASan memory mapping.
+//===----------------------------------------------------------------------===//
+#ifndef ASAN_MAPPING_H
+#define ASAN_MAPPING_H
+
+#include "asan_internal.h"
+
+// The full explanation of the memory mapping could be found here:
+// http://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm
+
+#if ASAN_FLEXIBLE_MAPPING_AND_OFFSET == 1
+extern __attribute__((visibility("default"))) uptr __asan_mapping_scale;
+extern __attribute__((visibility("default"))) uptr __asan_mapping_offset;
+# define SHADOW_SCALE (__asan_mapping_scale)
+# define SHADOW_OFFSET (__asan_mapping_offset)
+#else
+# if ASAN_ANDROID
+#  define SHADOW_SCALE (3)
+#  define SHADOW_OFFSET (0)
+# else
+#  define SHADOW_SCALE (3)
+#  if __WORDSIZE == 32
+#   define SHADOW_OFFSET (1 << 29)
+#  else
+#   define SHADOW_OFFSET (1ULL << 44)
+#  endif
+# endif
+#endif  // ASAN_FLEXIBLE_MAPPING_AND_OFFSET
+
+#define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE)
+#define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) | (SHADOW_OFFSET))
+#define SHADOW_TO_MEM(shadow) (((shadow) - SHADOW_OFFSET) << SHADOW_SCALE)
+
+#if __WORDSIZE == 64
+  static const uptr kHighMemEnd = 0x00007fffffffffffUL;
+#else  // __WORDSIZE == 32
+  static const uptr kHighMemEnd = 0xffffffff;
+#endif  // __WORDSIZE
+
+
+#define kLowMemBeg      0
+#define kLowMemEnd      (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0)
+
+#define kLowShadowBeg   SHADOW_OFFSET
+#define kLowShadowEnd   MEM_TO_SHADOW(kLowMemEnd)
+
+#define kHighMemBeg     (MEM_TO_SHADOW(kHighMemEnd) + 1)
+
+#define kHighShadowBeg  MEM_TO_SHADOW(kHighMemBeg)
+#define kHighShadowEnd  MEM_TO_SHADOW(kHighMemEnd)
+
+#define kShadowGapBeg   (kLowShadowEnd ? kLowShadowEnd + 1 : 16 * kPageSize)
+#define kShadowGapEnd   (kHighShadowBeg - 1)
+
+#define kGlobalAndStackRedzone \
+      (SHADOW_GRANULARITY < 32 ? 32 : SHADOW_GRANULARITY)
+
+namespace __asan {
+
+static inline bool AddrIsInLowMem(uptr a) {
+  return a < kLowMemEnd;
+}
+
+static inline bool AddrIsInLowShadow(uptr a) {
+  return a >= kLowShadowBeg && a <= kLowShadowEnd;
+}
+
+static inline bool AddrIsInHighMem(uptr a) {
+  return a >= kHighMemBeg && a <= kHighMemEnd;
+}
+
+static inline bool AddrIsInMem(uptr a) {
+  return AddrIsInLowMem(a) || AddrIsInHighMem(a);
+}
+
+static inline uptr MemToShadow(uptr p) {
+  CHECK(AddrIsInMem(p));
+  return MEM_TO_SHADOW(p);
+}
+
+static inline bool AddrIsInHighShadow(uptr a) {
+  return a >= kHighShadowBeg && a <=  kHighMemEnd;
+}
+
+static inline bool AddrIsInShadow(uptr a) {
+  return AddrIsInLowShadow(a) || AddrIsInHighShadow(a);
+}
+
+static inline bool AddrIsInShadowGap(uptr a) {
+  return a >= kShadowGapBeg && a <= kShadowGapEnd;
+}
+
+static inline bool AddrIsAlignedByGranularity(uptr a) {
+  return (a & (SHADOW_GRANULARITY - 1)) == 0;
+}
+
+static inline bool AddressIsPoisoned(uptr a) {
+  const uptr kAccessSize = 1;
+  u8 *shadow_address = (u8*)MemToShadow(a);
+  s8 shadow_value = *shadow_address;
+  if (shadow_value) {
+    u8 last_accessed_byte = (a & (SHADOW_GRANULARITY - 1))
+                                 + kAccessSize - 1;
+    return (last_accessed_byte >= shadow_value);
+  }
+  return false;
+}
+
+}  // namespace __asan
+
+#endif  // ASAN_MAPPING_H