[aarch64] Add support for pointer authentication B key

[binutils-gdb.git] / gas / doc / c-aarch64.texi

diff --git a/gas/doc/c-aarch64.texi b/gas/doc/c-aarch64.texi
index 8a116a40acb7e3041d7601ca219050181013a257..ca84c9d766fc28e67008f3764710dfe44c6b630a 100644 (file)
--- a/gas/doc/c-aarch64.texi
+++ b/gas/doc/c-aarch64.texi
@@ -183,6 +183,14 @@ automatically cause those extensions to be disabled.
  This implies @code{fp16}.
 @item @code{sb} @tab ARMv8-A @tab ARMv8.5-A or later
  @tab Enable the speculation barrier instruction sb.
+@item @code{predres} @tab ARMv8-A @tab ARMv8.5-A or later
+ @tab Enable the Execution and Data and Prediction instructions.
+@item @code{rng} @tab ARMv8.5-A @tab No
+ @tab Enable ARMv8.5-A random number instructions.
+@item @code{ssbs} @tab ARMv8-A @tab ARMv8.5-A or later
+ @tab Enable Speculative Store Bypassing Safe state read and write.
+@item @code{memtag} @tab ARMv8.5-A @tab No
+ @tab Enable ARMv8.5-A Memory Tagging Extensions.
 @end multitable
 
 @node AArch64 Syntax
@@ -427,6 +435,14 @@ as the @code{.dword} directive.
 @c YYYYYYYYYYYYYYYYYYYYYYYYYY
 @c ZZZZZZZZZZZZZZZZZZZZZZZZZZ
 
+@cindex @code{.cfi_b_key_frame} directive, AArch64
+@item  @code{.cfi_b_key_frame}
+The @code{.cfi_b_key_frame} directive inserts a 'B' character into the CIE
+corresponding to the current frame's FDE, meaning that its return address has
+been signed with the B-key.  If two frames are signed with differing keys then
+they will not share the same CIE.  This information is intended to be used by
+the stack unwinder in order to properly authenticate return addresses.
+
 @end table
 
 @node AArch64 Opcodes