From 565b1a1430fd2ce3e53fe9b1be5838e743a194f6 Mon Sep 17 00:00:00 2001 From: Ved Shanbhogue Date: Tue, 22 Nov 2022 15:18:18 -0600 Subject: [PATCH] encoding clarifications --- cfi_backward.adoc | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/cfi_backward.adoc b/cfi_backward.adoc index ba1605e..6f1bd29 100644 --- a/cfi_backward.adoc +++ b/cfi_backward.adoc @@ -34,6 +34,8 @@ using the `mop.r` and `mop.rr` instructions defined by the Zimops extension. | 2+^|`12` 2+^|`5` 2+^|`3` 2+^|`5` 2+^|`7` |=== +Encoding `rs1` as `x0` is not supported for `sspush`. +Encoding `rd` as `x0` is not supported for `sspop`. [width=100%] [%header, cols="6,<3,>3,<3,>3,<3,>3,<3,>3,<3,>3,<3,>3", grid=rows, frame=none] @@ -45,6 +47,8 @@ using the `mop.r` and `mop.rr` instructions defined by the Zimops extension. | 2+^|`7` 2+^|`5` 2+^|`5` 2+^|`3` 2+^|`5` 2+^|`7` |=== +Encoding `rd` as `x0` is not supported for `ssamoswap`. + When `menvcfg.CFI` is 0, then Zisslpcfi is not enabled for privilege modes less than M and backward-edge CFI is not active at privilege levels less than M. @@ -125,7 +129,7 @@ using shadow stacks is as follows: : : sspop x5 # pop from shadow stack into x5 - sschkra x1, x5 # compare link register x1 to shadow + sschkra x5, x1 # compare link register x1 to shadow # link register x5; faults if not same ret