aarch64_sve_change_el() currently assumes that SME implies
SVE, and will return without doing anything if SVE is not
implemented, skipping a possible requirement to change
the vector register state because the SME vector length
has changed. Update it to handle SME also.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/helper.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 732c3a9eba..655ce73ee1 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -10127,8 +10127,8 @@ void aarch64_sve_change_el(CPUARMState *env, int old_el,
     int old_len, new_len;
     bool old_a64, new_a64, sm;
 
-    /* Nothing to do if no SVE.  */
-    if (!cpu_isar_feature(aa64_sve, cpu)) {
+    /* Nothing to do if no SVE or SME.  */
+    if (!cpu_isar_feature(aa64_sve, cpu) && !cpu_isar_feature(aa64_sme, cpu)) {
         return;
     }
 
-- 
2.43.0

Peter Maydell <peter.maydell@linaro.org> writes:

> aarch64_sve_change_el() currently assumes that SME implies
> SVE, and will return without doing anything if SVE is not
> implemented, skipping a possible requirement to change
> the vector register state because the SME vector length
> has changed. Update it to handle SME also.
>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro

On 29/1/26 12:34, Peter Maydell wrote:
> aarch64_sve_change_el() currently assumes that SME implies
> SVE, and will return without doing anything if SVE is not
> implemented, skipping a possible requirement to change
> the vector register state because the SME vector length
> has changed. Update it to handle SME also.
> 
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   target/arm/helper.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 732c3a9eba..655ce73ee1 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -10127,8 +10127,8 @@ void aarch64_sve_change_el(CPUARMState *env, int old_el,

Could we rename the method? Maybe aarch64_vq_change_el()?

>       int old_len, new_len;
>       bool old_a64, new_a64, sm;
>   
> -    /* Nothing to do if no SVE.  */
> -    if (!cpu_isar_feature(aa64_sve, cpu)) {
> +    /* Nothing to do if no SVE or SME.  */
> +    if (!cpu_isar_feature(aa64_sve, cpu) && !cpu_isar_feature(aa64_sme, cpu)) {
>           return;
>       }
>