Re: [PATCH v2 08/14] tests/tcg/s390x: Test CKSM

[Thomas Huth]

On 19/07/2023 11.44, Ilya Leoshkevich wrote:
> Add a small test to prevent regressions.
>
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/s390x/Makefile.softmmu-target |  1 +
>   tests/tcg/s390x/cksm.S                  | 29 +++++++++++++++++++++++++
>   2 files changed, 30 insertions(+)
>   create mode 100644 tests/tcg/s390x/cksm.S
>
> diff --git a/tests/tcg/s390x/Makefile.softmmu-target 
> b/tests/tcg/s390x/Makefile.softmmu-target
> index 242c7b0f83c..e813e318db9 100644
> --- a/tests/tcg/s390x/Makefile.softmmu-target
> +++ b/tests/tcg/s390x/Makefile.softmmu-target
> @@ -16,6 +16,7 @@ LDFLAGS=-nostdlib -static
>   
>   ASM_TESTS =                                                                    \
>       bal                                                                       
>  \
> +    cksm                                                                       
> \
>       exrl-ssm-early                                                            
>  \
>       sam                                                                       
>  \
>       lpsw                                                                      
>  \
> diff --git a/tests/tcg/s390x/cksm.S b/tests/tcg/s390x/cksm.S
> new file mode 100644
> index 00000000000..a45f3ef6bfd
> --- /dev/null
> +++ b/tests/tcg/s390x/cksm.S
> @@ -0,0 +1,29 @@
> +    .org 0x8e
> +program_interruption_code:
> +    .org 0x1d0                         /* program new PSW */
> +    .quad 0,pgm
> +    .org 0x200                         /* lowcore padding */
> +    .globl _start
> +_start:
> +    lmg %r0,%r1,cksm_args
> +    cksm %r2,%r0
> +    c %r2,cksm_exp
> +    jne failure
> +    cksm %r2,%r15

Clang is smart enough to detect that this is a bad instruction:

$ make check-tcg
  BUILD   s390x-softmmu guest-tests
tests/tcg/s390x/cksm.S:12:14: error: invalid register pair
    cksm %r2,%r15
             ^

I guess you have to manually create the opcode here?

 Thomas