On 10.08.2018 05:01, Pavel Zbitskiy wrote:
> Suppose psw.mask=0x0000000080000000, cc=2, r1=0 and we do "ipm 1".
> This command must touch only bits 32-39, so the expected output
> is r1=0x20000000. However, currently qemu yields r1=0x20008000,
> because irrelevant parts of PSW leak into r1 during program mask
> transfer.
>
> Signed-off-by: Pavel Zbitskiy <pavel.zbits...@gmail.com>
> ---
> target/s390x/translate.c | 17 +++++++----------
> tests/tcg/s390x/Makefile.target | 1 +
> tests/tcg/s390x/ipm.c | 22 ++++++++++++++++++++++
> 3 files changed, 30 insertions(+), 10 deletions(-)
> create mode 100644 tests/tcg/s390x/ipm.c
>
> diff --git a/target/s390x/translate.c b/target/s390x/translate.c
> index d0d2c3412f..6f8fbda222 100644
> --- a/target/s390x/translate.c
> +++ b/target/s390x/translate.c
> @@ -2437,20 +2437,17 @@ static DisasJumpType op_insi(DisasContext *s,
> DisasOps *o)
>
> static DisasJumpType op_ipm(DisasContext *s, DisasOps *o)
> {
> - TCGv_i64 t1;
> + TCGv_i64 t1, t2;
>
> gen_op_calc_cc(s);
> - tcg_gen_andi_i64(o->out, o->out, ~0xff000000ull);
> -
> t1 = tcg_temp_new_i64();
> - tcg_gen_shli_i64(t1, psw_mask, 20);
> - tcg_gen_shri_i64(t1, t1, 36);
> - tcg_gen_or_i64(o->out, o->out, t1);
> -
> - tcg_gen_extu_i32_i64(t1, cc_op);
> - tcg_gen_shli_i64(t1, t1, 28);
> - tcg_gen_or_i64(o->out, o->out, t1);
> + tcg_gen_extract_i64(t1, psw_mask, 40, 4);
> + t2 = tcg_temp_new_i64();
> + tcg_gen_extu_i32_i64(t2, cc_op);
> + tcg_gen_deposit_i64(t1, t1, t2, 4, 60);
> + tcg_gen_deposit_i64(o->out, o->out, t1, 24, 8);
Not checked, but I wonder if you could avoid the second temp variable by
simply depositing right from psw_mask/cc into t1 and from there into out
(one step at a time).
> tcg_temp_free_i64(t1);
> + tcg_temp_free_i64(t2);
> return DISAS_NEXT;
> }
>
> diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
> index f62f950d8e..c800a582e5 100644
> --- a/tests/tcg/s390x/Makefile.target
> +++ b/tests/tcg/s390x/Makefile.target
> @@ -2,3 +2,4 @@ VPATH+=$(SRC_PATH)/tests/tcg/s390x
> CFLAGS+=-march=zEC12 -m64
> TESTS+=hello-s390x
> TESTS+=csst
> +TESTS+=ipm
> diff --git a/tests/tcg/s390x/ipm.c b/tests/tcg/s390x/ipm.c
> new file mode 100644
> index 0000000000..742f3a18c5
> --- /dev/null
> +++ b/tests/tcg/s390x/ipm.c
> @@ -0,0 +1,22 @@
> +#include <stdint.h>
> +#include <unistd.h>
> +
> +int main(void)
> +{
> + uint32_t op1 = 0x55555555;
> + uint32_t op2 = 0x44444444;
> + uint64_t cc = 0xffffffffffffffffull;
> +
> + asm volatile(
> + " clc 0(4,%[op1]),0(%[op2])\n"
> + " ipm %[cc]\n"
> + : [cc] "+r" (cc)
> + : [op1] "r" (&op1),
> + [op2] "r" (&op2)
> + : "cc");
> + if (cc != 0xffffffff20ffffffull) {
> + write(1, "bad cc\n", 7);
> + return 1;
> + }
> + return 0;
> +}
>
--
Thanks,
David / dhildenb
