[asan] allow asan to use SizeClassAllocator32 on a 64-bit platform (if SANITIZER_CAN_USE_ALLOCATOR64=0). No functionality change by default is intended

llvm-svn: 198044

compiler-rt/lib/asan/asan_allocator2.cc

@@ -50,27 +50,31 @@ struct AsanMapUnmapCallback {
   }
 };
 
-#if SANITIZER_WORDSIZE == 64
-#if defined(__powerpc64__)
+#if SANITIZER_CAN_USE_ALLOCATOR64
+# if defined(__powerpc64__)
 const uptr kAllocatorSpace =  0xa0000000000ULL;
 const uptr kAllocatorSize  =  0x20000000000ULL;  // 2T.
-#else
+# else
 const uptr kAllocatorSpace = 0x600000000000ULL;
 const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
-#endif
+# endif
 typedef DefaultSizeClassMap SizeClassMap;
 typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, 0 /*metadata*/,
     SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator;
-#elif SANITIZER_WORDSIZE == 32
-static const u64 kAddressSpaceSize = 1ULL << 32;
-typedef CompactSizeClassMap SizeClassMap;
+#else  // Fallback to SizeClassAllocator32.
 static const uptr kRegionSizeLog = 20;
-static const uptr kFlatByteMapSize = kAddressSpaceSize >> kRegionSizeLog;
-typedef SizeClassAllocator32<0, kAddressSpaceSize, 16,
+static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
+# if SANITIZER_WORDSIZE == 32
+typedef FlatByteMap<kNumRegions> ByteMap;
+# elif SANITIZER_WORDSIZE == 64
+typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
+# endif
+typedef CompactSizeClassMap SizeClassMap;
+typedef SizeClassAllocator32<0, SANITIZER_MMAP_RANGE_SIZE, 16,
   SizeClassMap, kRegionSizeLog,
-  FlatByteMap<kFlatByteMapSize>,
+  ByteMap,
   AsanMapUnmapCallback> PrimaryAllocator;
-#endif
+#endif  // SANITIZER_CAN_USE_ALLOCATOR64
 
 typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
 typedef LargeMmapAllocator<AsanMapUnmapCallback> SecondaryAllocator;

compiler-rt/lib/sanitizer_common/sanitizer_allocator_internal.h

@@ -24,14 +24,13 @@ namespace __sanitizer {
 typedef CompactSizeClassMap InternalSizeClassMap;
 
 static const uptr kInternalAllocatorSpace = 0;
+static const u64 kInternalAllocatorSize = SANITIZER_MMAP_RANGE_SIZE;
 #if SANITIZER_WORDSIZE == 32
-static const u64 kInternalAllocatorSize = (1ULL << 32);
 static const uptr kInternalAllocatorRegionSizeLog = 20;
 static const uptr kInternalAllocatorNumRegions =
     kInternalAllocatorSize >> kInternalAllocatorRegionSizeLog;
 typedef FlatByteMap<kInternalAllocatorNumRegions> ByteMap;
 #else
-static const u64 kInternalAllocatorSize = (1ULL << 47);
 static const uptr kInternalAllocatorRegionSizeLog = 24;
 static const uptr kInternalAllocatorNumRegions =
     kInternalAllocatorSize >> kInternalAllocatorRegionSizeLog;

compiler-rt/lib/sanitizer_common/sanitizer_common.h

@@ -314,12 +314,6 @@ INLINE int ToLower(int c) {
   return (c >= 'A' && c <= 'Z') ? (c + 'a' - 'A') : c;
 }
 
-#if SANITIZER_WORDSIZE == 64
-# define FIRST_32_SECOND_64(a, b) (b)
-#else
-# define FIRST_32_SECOND_64(a, b) (a)
-#endif
-
 // A low-level vector based on mmap. May incur a significant memory overhead for
 // small vectors.
 // WARNING: The current implementation supports only POD types.

compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h

@@ -34,12 +34,6 @@
 # define SANITIZER_SUPPORTS_WEAK_HOOKS 0
 #endif
 
-#if __LP64__ || defined(_WIN64)
-#  define SANITIZER_WORDSIZE 64
-#else
-#  define SANITIZER_WORDSIZE 32
-#endif
-
 // GCC does not understand __has_feature
 #if !defined(__has_feature)
 # define __has_feature(x) 0

compiler-rt/lib/sanitizer_common/sanitizer_platform.h

@@ -50,4 +50,31 @@
 
 #define SANITIZER_POSIX (SANITIZER_LINUX || SANITIZER_MAC)
 
+#if __LP64__ || defined(_WIN64)
+#  define SANITIZER_WORDSIZE 64
+#else
+#  define SANITIZER_WORDSIZE 32
+#endif
+
+#if SANITIZER_WORDSIZE == 64
+# define FIRST_32_SECOND_64(a, b) (b)
+#else
+# define FIRST_32_SECOND_64(a, b) (a)
+#endif
+
+// By default we allow to use SizeClassAllocator64 on 64-bit platform.
+// But in some cases (e.g. AArch64's 39-bit address space) SizeClassAllocator64
+// does not work well and we need to fallback to SizeClassAllocator32.
+// For such platforms build this code with -DSANITIZER_CAN_USE_ALLOCATOR64=0 or
+// change the definition of SANITIZER_CAN_USE_ALLOCATOR64 here.
+#ifndef SANITIZER_CAN_USE_ALLOCATOR64
+# define SANITIZER_CAN_USE_ALLOCATOR64 (SANITIZER_WORDSIZE == 64)
+#endif
+
+// The range of addresses which can be returned my mmap.
+// FIXME: this value should be different on different platforms,
+// e.g. on AArch64 it is most likely (1ULL << 39). Larger values will still work
+// but will consume more memory for TwoLevelByteMap.
+#define SANITIZER_MMAP_RANGE_SIZE FIRST_32_SECOND_64(1ULL << 32, 1ULL << 47)
+
 #endif // SANITIZER_PLATFORM_H