Re: [Qemu-devel] [PATCH v4] target/s390x: Add support for the TEST BLOCK instruction

[Richard Henderson]

On 05/18/2017 10:26 AM, Thomas Huth wrote:
> TEST BLOCK was likely once used to execute basic memory
> tests, but nowadays it's just a (slow) way to clear a page.
>
> Signed-off-by: Thomas Huth<address@hidden>
> ---
>   v4:
>   - Switched TCG_CALL_NO_RWG back to TCG_CALL_NO_WG as indicated by Richard
>
>   v3:
>   - Use TCG_CALL_NO_RWG instead of TCG_CALL_NO_WG
>   - Use potential_page_fault() since the helper can generate an exception
>
>   v2:
>   - Use DEF_HELPER_FLAGS_2 instead for DEF_HELPER_2 for returning CC value
>   - Convert real to absolute address
>   - Added a check for valid RAM page
>   - Added low-address protection check
>
>   target/s390x/cpu.h         |  1 +
>   target/s390x/helper.h      |  1 +
>   target/s390x/insn-data.def |  2 ++
>   target/s390x/mem_helper.c  | 28 ++++++++++++++++++++++++++++
>   target/s390x/mmu_helper.c  |  2 +-
>   target/s390x/translate.c   | 11 +++++++++++
>   6 files changed, 44 insertions(+), 1 deletion(-)

Reviewed-by: Richard Henderson <address@hidden>


r~