diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -108,6 +108,7 @@
 static const uint64_t kRISCV64_ShadowOffset64 = 0xd55550000;
 static const uint64_t kFreeBSD_ShadowOffset32 = 1ULL << 30;
 static const uint64_t kFreeBSD_ShadowOffset64 = 1ULL << 46;
+static const uint64_t kFreeBSDAArch64_ShadowOffset64 = 1ULL << 47;
 static const uint64_t kFreeBSDKasan_ShadowOffset64 = 0xdffff7c000000000;
 static const uint64_t kNetBSD_ShadowOffset32 = 1ULL << 30;
 static const uint64_t kNetBSD_ShadowOffset64 = 1ULL << 46;
@@ -523,6 +524,8 @@
       Mapping.Offset = kPPC64_ShadowOffset64;
     else if (IsSystemZ)
       Mapping.Offset = kSystemZ_ShadowOffset64;
+    else if (IsFreeBSD && IsAArch64)
+        Mapping.Offset = kFreeBSDAArch64_ShadowOffset64;
     else if (IsFreeBSD && !IsMIPS64) {
       if (IsKasan)
         Mapping.Offset = kFreeBSDKasan_ShadowOffset64;
diff --git a/llvm/test/Instrumentation/AddressSanitizer/freebsd.ll b/llvm/test/Instrumentation/AddressSanitizer/freebsd.ll
--- a/llvm/test/Instrumentation/AddressSanitizer/freebsd.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/freebsd.ll
@@ -8,6 +8,11 @@
 ; RUN:     -data-layout="e-m:e-i64:64-f80:128-n8:16:32:64-S128" | \
 ; RUN:     FileCheck --check-prefix=CHECK-64 %s
 
+; RUN: opt < %s -passes='asan-pipeline' -S \
+; RUN:     -mtriple=aarch64-unknown-freebsd \
+; RUN:     -data-layout="e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128" | \
+; RUN:     FileCheck --check-prefix=CHECK-AARCH64 %s
+
 ; RUN: opt < %s -passes='asan-pipeline' -S \
 ; RUN:     -mtriple=mips64-unknown-freebsd \
 ; RUN:     -data-layout="E-m:e-i64:64-n32:64-S128" | \
@@ -33,6 +38,13 @@
 ; CHECK-64-NEXT: {{70368744177664}}
 ; CHECK-64: ret
 
+; CHECK-AARCH64: @read_4_bytes
+; CHECK-AARCH64-NOT: ret
+; Check for ASAN's Offset for 64-bit (2^47 or 0x800000000000)
+; CHECK-AARCH64: lshr {{.*}} 3
+; CHECK-AARCH64-NEXT: {{140737488355328}}
+; CHECK-AARCH64: ret
+
 ; CHECK-MIPS64: @read_4_bytes
 ; CHECK-MIPS64-NOT: ret
 ; Check for ASAN's Offset for 64-bit (2^37 or 0x2000000000)