Index: lib/Transforms/Instrumentation/AddressSanitizer.cpp
===================================================================
--- lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -69,7 +69,6 @@
 static const uint64_t kDefaultShadowOffset64 = 1ULL << 44;
 static const uint64_t kDynamicShadowSentinel = ~(uint64_t)0;
 static const uint64_t kIOSShadowOffset32 = 1ULL << 30;
-static const uint64_t kIOSShadowOffset64 = 0x120200000;
 static const uint64_t kIOSSimShadowOffset32 = 1ULL << 30;
 static const uint64_t kIOSSimShadowOffset64 = kDefaultShadowOffset64;
 static const uint64_t kSmallX86_64ShadowOffset = 0x7FFF8000;  // < 2G.
@@ -434,7 +433,9 @@
       Mapping.Offset = kMIPS64_ShadowOffset64;
     else if (IsIOS)
       // If we're targeting iOS and x86, the binary is built for iOS simulator.
-      Mapping.Offset = IsX86_64 ? kIOSSimShadowOffset64 : kIOSShadowOffset64;
+      // We are using dynamic shadow offset on the 64-bit devices.
+      Mapping.Offset =
+        IsX86_64 ? kIOSSimShadowOffset64 : kDynamicShadowSentinel;
     else if (IsAArch64)
       Mapping.Offset = kAArch64_ShadowOffset64;
     else