diff --git a/compiler-rt/lib/asan/asan_rtl_x86_64.S b/compiler-rt/lib/asan/asan_rtl_x86_64.S
index 0b7363018f425..e44587ac4331c 100644
--- a/compiler-rt/lib/asan/asan_rtl_x86_64.S
+++ b/compiler-rt/lib/asan/asan_rtl_x86_64.S
@@ -27,7 +27,12 @@ FNAME(reg, op, s, i): ;\
 #define ASAN_MEMORY_ACCESS_INITIAL_CHECK_ADD(reg, op, s) \
         mov    %##reg,%r10 ;\
         shr    $0x3,%r10 ;\
+        .if ASAN_SHADOW_OFFSET_CONST < 0x80000000   ;\
         movsbl ASAN_SHADOW_OFFSET_CONST(%r10),%r10d ;\
+        .else                                       ;\
+        movabsq $ASAN_SHADOW_OFFSET_CONST,%r11      ;\
+        movsbl (%r10,%r11),%r10d                    ;\
+        .endif                                      ;\
         test   %r10d,%r10d ;\
         jne    CLABEL(reg, op, s, add) ;\
 RLABEL(reg, op, s, add): ;\