[NFC][compiler-rt][asan] Unify asan and lsan allocator settings

[leonardchan]

Summary

This updates existing asan allocator settings to use the same allocator settings as what lsan uses for platforms where they already match.

[leonardchan]

*ping*

compiler-rt/lib/asan/asan_allocator.h

 };
 
 struct AsanMapUnmapCallback {
   void OnMap(uptr p, uptr size) const;
   void OnUnmap(uptr p, uptr size) const;
 };
 
 #if SANITIZER_CAN_USE_ALLOCATOR64
-# if SANITIZER_FUCHSIA
-const uptr kAllocatorSpace = ~(uptr)0;
-const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
-typedef DefaultSizeClassMap SizeClassMap;
-# elif defined(__powerpc64__)
+# if defined(__powerpc64__)
 const uptr kAllocatorSpace = ~(uptr)0;
+// NOTE: This differs slightly from the LSan allocator size which is 4T.
 const uptr kAllocatorSize  =  0x20000000000ULL;  // 2T.
 typedef DefaultSizeClassMap SizeClassMap;
 # elif defined(__aarch64__) && SANITIZER_ANDROID
 // Android needs to support 39, 42 and 48 bit VMA.
 const uptr kAllocatorSpace =  ~(uptr)0;
 const uptr kAllocatorSize  =  0x2000000000ULL;  // 128G.
 typedef VeryCompactSizeClassMap SizeClassMap;
 #elif SANITIZER_RISCV64

 const uptr kAllocatorSpace = ~(uptr)0;
 const uptr kAllocatorSize = 0x20000000000ULL;  // 2T.
 typedef DefaultSizeClassMap SizeClassMap;
 # elif SANITIZER_WINDOWS
 const uptr kAllocatorSpace = ~(uptr)0;
 const uptr kAllocatorSize  =  0x8000000000ULL;  // 500G
 typedef DefaultSizeClassMap SizeClassMap;
 # else
-const uptr kAllocatorSpace = 0x600000000000ULL;
-const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
-typedef DefaultSizeClassMap SizeClassMap;
+// Use LSan's allocator configs.
+static const uptr kSpaceBeg = __lsan::kAllocatorSpace;
+static const uptr kSpaceSize = __lsan::kAllocatorSize;
+typedef __lsan::SizeClassMap SizeClassMap;
 # endif
 template <typename AddressSpaceViewTy>
 struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
   static const uptr kSpaceBeg = kAllocatorSpace;
   static const uptr kSpaceSize = kAllocatorSize;
   static const uptr kMetadataSize = 0;
   typedef __asan::SizeClassMap SizeClassMap;
   typedef AsanMapUnmapCallback MapUnmapCallback;