Clear non-significant bits of address on memory access

[deliverable/binutils-gdb.git] / gdb / aarch64-tdep.c

diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
index 6a0d4b744c89c39d5b62b7dcc12273fccb0c32e6..383d584b5266459ca6d6722507a700acc92b56d6 100644 (file)
--- a/gdb/aarch64-tdep.c
+++ b/gdb/aarch64-tdep.c
@@ -2970,6 +2970,11 @@ aarch64_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_tdesc_pseudo_register_reggroup_p (gdbarch,
                                        aarch64_pseudo_register_reggroup_p);
 
+  /* The top byte of an address is known as the "tag" and is
+     ignored by the kernel, the hardware, etc. and can be regarded
+     as additional data associated with the address.  */
+  set_gdbarch_significant_addr_bit (gdbarch, 56);
+
   /* ABI */
   set_gdbarch_short_bit (gdbarch, 16);
   set_gdbarch_int_bit (gdbarch, 32);