On Tue, Jul 07, 2026 at 02:37:47PM +0000, Richard Earnshaw via Sourceware Forge
wrote:
> From: Richard Earnshaw <[email protected]>
>
> There are no known implementations of the MPAMV2_VID extension, and
> Arm has decided to remove it from the AArch64 architecture specification.
> This patch implements that withdrawal. The only purpose of the +mpamv2
> architectural feature extension was to enable the instructions added
> by MPAMV2_VID in the assembler and these have also been removed. The
> feature extension is thus redundant and has been removed. The sysreg
> specifications have been updated to conform with similar sysregs that
> have no associated instructions in the feature.
Ok for master, and ok for the release branch if noone objects in 48 hours.
Alice
>
> gcc/ChangeLog:
>
> * config/aarch64/aarch64-option-extensions.def (AARCH64_OPT_EXTENSION):
> Remove +mpamv2.
> * config/aarch64/aarch64-sys-regs.def: Remove sysregs associated
> with MPAMv2_VID and adjust other related sysregs to use the
> base permitted architecture.
> * doc/invoke.texi (aarch64: +mpamv2): Remove option.
> ---
> gcc/config/aarch64/aarch64-option-extensions.def | 2 --
> gcc/config/aarch64/aarch64-sys-regs.def | 11 ++++-------
> gcc/doc/invoke.texi | 2 --
> 3 files changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/gcc/config/aarch64/aarch64-option-extensions.def
> b/gcc/config/aarch64/aarch64-option-extensions.def
> index b23e44efeb03..85483f38cc47 100644
> --- a/gcc/config/aarch64/aarch64-option-extensions.def
> +++ b/gcc/config/aarch64/aarch64-option-extensions.def
> @@ -359,8 +359,6 @@ AARCH64_OPT_EXTENSION("tlbid", TLBID, (), (), (), "")
>
> AARCH64_OPT_EXTENSION("gcie", GCIE, (), (), (), "")
>
> -AARCH64_OPT_EXTENSION("mpamv2", MPAMv2, (), (), (), "")
> -
> AARCH64_OPT_EXTENSION("lscp", LSCP, (), (), (), "")
>
> AARCH64_OPT_EXTENSION("mops-go", MOPS_GO, (MOPS, MEMTAG), (), (), "")
> diff --git a/gcc/config/aarch64/aarch64-sys-regs.def
> b/gcc/config/aarch64/aarch64-sys-regs.def
> index 9daa178ed7b7..1efbc3f3de5a 100644
> --- a/gcc/config/aarch64/aarch64-sys-regs.def
> +++ b/gcc/config/aarch64/aarch64-sys-regs.def
> @@ -922,16 +922,13 @@
> SYSREG ("mpambwcap_el2", CPENC (3,4,10,5,6), 0,
> AARCH64_FEATURE (V9_3A)) /* MPAM_PE_BW_CTRL */
> SYSREG ("mpambwidr_el1", CPENC (3,0,10,4,5), F_REG_READ,
> AARCH64_FEATURE (V9_3A)) /* MPAM_PE_BW_CTRL */
> SYSREG ("mpambwsm_el1", CPENC (3,0,10,5,7), 0,
> AARCH64_FEATURES (2, SME, V9_3A)) /* SME && MPAM_PE_BW_CTRL */
> - SYSREG ("mpamctl_el1", CPENC (3,0,10,5,2), 0,
> AARCH64_FEATURE (MPAMv2))
> - SYSREG ("mpamctl_el12", CPENC (3,5,10,5,2), 0,
> AARCH64_FEATURE (MPAMv2))
> - SYSREG ("mpamctl_el2", CPENC (3,4,10,5,2), 0,
> AARCH64_FEATURE (MPAMv2))
> - SYSREG ("mpamctl_el3", CPENC (3,6,10,5,2), 0,
> AARCH64_FEATURE (MPAMv2))
> + SYSREG ("mpamctl_el1", CPENC (3,0,10,5,2), 0,
> AARCH64_FEATURE (V9_3A)) /* MPAMv2 */
> + SYSREG ("mpamctl_el12", CPENC (3,5,10,5,2), 0,
> AARCH64_FEATURE (V9_3A)) /* MPAMv2 */
> + SYSREG ("mpamctl_el2", CPENC (3,4,10,5,2), 0,
> AARCH64_FEATURE (V9_3A)) /* MPAMv2 */
> + SYSREG ("mpamctl_el3", CPENC (3,6,10,5,2), 0,
> AARCH64_FEATURE (V9_3A)) /* MPAMv2 */
> SYSREG ("mpamhcr_el2", CPENC (3,4,10,4,0), 0,
> AARCH64_FEATURE (V8_2A)) /* MPAM */
> SYSREG ("mpamidr_el1", CPENC (3,0,10,4,4), F_REG_READ,
> AARCH64_FEATURE (V8_2A)) /* MPAM */
> SYSREG ("mpamsm_el1", CPENC (3,0,10,5,3), 0,
> AARCH64_FEATURES (2, SME, V8_2A)) /* SME && MPAM */
> - SYSREG ("mpamvidcr_el2", CPENC (3,4,10,7,0), 0,
> AARCH64_FEATURE (MPAMv2))
> - SYSREG ("mpamvidsr_el2", CPENC (3,4,10,7,1), 0,
> AARCH64_FEATURE (MPAMv2))
> - SYSREG ("mpamvidsr_el3", CPENC (3,6,10,7,1), 0,
> AARCH64_FEATURE (MPAMv2))
> SYSREG ("mpamvpm0_el2", CPENC (3,4,10,6,0), 0,
> AARCH64_FEATURE (V8_2A)) /* MPAM */
> SYSREG ("mpamvpm1_el2", CPENC (3,4,10,6,1), 0,
> AARCH64_FEATURE (V8_2A)) /* MPAM */
> SYSREG ("mpamvpm2_el2", CPENC (3,4,10,6,2), 0,
> AARCH64_FEATURE (V8_2A)) /* MPAM */
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 455ea08d7c73..d0a14484547e 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -22082,8 +22082,6 @@ Enable the TIndex Exception-like Vector Extension.
> Enable the TLBI Domains Extension.
> @item gcie
> Enable the GICv5 (Generic Interrupt Controller) CPU Interface Extension.
> -@item mpamv2
> -Enable MPAMv2 system registers.
> @item lscp
> Enable the load acquire and store release pair extension.
> @item mops-go
> --
> 2.54.0
>
