[PATCH v3 0/4] target/s390x: Emulate CVDG and CVB*

[PATCH v3 0/4] target/s390x: Emulate CVDG and CVB*

[Ilya Leoshkevich]

v2: https://lists.gnu.org/archive/html/qemu-devel/2024-01/msg05048.html
v2 -> v3: Resurrect an old CVB* patch (Thomas).
          Add Richard's R-b.

v1: https://lists.gnu.org/archive/html/qemu-devel/2024-01/msg02865.html
v1 -> v2: Fix !CONFIG_INT128 builds (Richard).

Hi,

Ido reported that we are missing the CVDG emulation (which is very
similar to the existing CVD emulation). This series adds it along with
a test.

Best regards,
Ilya

Ilya Leoshkevich (3):
  target/s390x: Emulate CVDG
  tests/tcg/s390x: Test CONVERT TO DECIMAL
  tests/tcg/s390x: Test CONVERT TO BINARY

Pavel Zbitskiy (1):
  target/s390x: implement CVB, CVBY and CVBG

 target/s390x/helper.h            |  2 ++
 target/s390x/tcg/insn-data.h.inc |  5 +++
 target/s390x/tcg/int_helper.c    | 61 ++++++++++++++++++++++++++++++++
 target/s390x/tcg/translate.c     | 20 +++++++++++
 tests/tcg/s390x/Makefile.target  |  2 ++
 tests/tcg/s390x/cvb.c            | 47 ++++++++++++++++++++++++
 tests/tcg/s390x/cvd.c            | 45 +++++++++++++++++++++++
 7 files changed, 182 insertions(+)
 create mode 100644 tests/tcg/s390x/cvb.c
 create mode 100644 tests/tcg/s390x/cvd.c

-- 
2.43.0

[PATCH v3 1/4] target/s390x: Emulate CVDG

[Ilya Leoshkevich]

CVDG is the same as CVD, except that it converts 64 bits into 128,
rather than 32 into 64. Create a new helper, which uses Int128
wrappers.

Reported-by: Ido Plat <Ido.Plat@ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 target/s390x/helper.h            |  1 +
 target/s390x/tcg/insn-data.h.inc |  1 +
 target/s390x/tcg/int_helper.c    | 21 +++++++++++++++++++++
 target/s390x/tcg/translate.c     |  8 ++++++++
 4 files changed, 31 insertions(+)

diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 05102578fc9..332a9a9c632 100644
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -89,6 +89,7 @@ DEF_HELPER_FLAGS_2(sqeb, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_2(sqdb, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_2(sqxb, TCG_CALL_NO_WG, i128, env, i128)
 DEF_HELPER_FLAGS_1(cvd, TCG_CALL_NO_RWG_SE, i64, s32)
+DEF_HELPER_FLAGS_1(cvdg, TCG_CALL_NO_RWG_SE, i128, s64)
 DEF_HELPER_FLAGS_4(pack, TCG_CALL_NO_WG, void, env, i32, i64, i64)
 DEF_HELPER_FLAGS_4(pka, TCG_CALL_NO_WG, void, env, i64, i64, i32)
 DEF_HELPER_FLAGS_4(pku, TCG_CALL_NO_WG, void, env, i64, i64, i32)
diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc
index 2f07f39d9cb..388dcb8dbbc 100644
--- a/target/s390x/tcg/insn-data.h.inc
+++ b/target/s390x/tcg/insn-data.h.inc
@@ -296,6 +296,7 @@
 /* CONVERT TO DECIMAL */
     C(0x4e00, CVD,     RX_a,  Z,   r1_o, a2, 0, 0, cvd, 0)
     C(0xe326, CVDY,    RXY_a, LD,  r1_o, a2, 0, 0, cvd, 0)
+    C(0xe32e, CVDG,    RXY_a, Z,   r1_o, a2, 0, 0, cvdg, 0)
 /* CONVERT TO FIXED */
     F(0xb398, CFEBR,   RRF_e, Z,   0, e2, new, r1_32, cfeb, 0, IF_BFP)
     F(0xb399, CFDBR,   RRF_e, Z,   0, f2, new, r1_32, cfdb, 0, IF_BFP)
diff --git a/target/s390x/tcg/int_helper.c b/target/s390x/tcg/int_helper.c
index eb8e6dd1b57..121e3006a65 100644
--- a/target/s390x/tcg/int_helper.c
+++ b/target/s390x/tcg/int_helper.c
@@ -118,6 +118,27 @@ uint64_t HELPER(cvd)(int32_t reg)
     return dec;
 }
 
+Int128 HELPER(cvdg)(int64_t reg)
+{
+    /* positive 0 */
+    Int128 dec = int128_make64(0x0c);
+    Int128 bin = int128_makes64(reg);
+    Int128 base = int128_make64(10);
+    int shift;
+
+    if (!int128_nonneg(bin)) {
+        bin = int128_neg(bin);
+        dec = int128_make64(0x0d);
+    }
+
+    for (shift = 4; (shift < 128) && int128_nz(bin); shift += 4) {
+        dec = int128_or(dec, int128_lshift(int128_remu(bin, base), shift));
+        bin = int128_divu(bin, base);
+    }
+
+    return dec;
+}
+
 uint64_t HELPER(popcnt)(uint64_t val)
 {
     /* Note that we don't fold past bytes. */
diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
index a5fd9cccaa5..c2fdc920a50 100644
--- a/target/s390x/tcg/translate.c
+++ b/target/s390x/tcg/translate.c
@@ -2233,6 +2233,14 @@ static DisasJumpType op_cvd(DisasContext *s, DisasOps *o)
     return DISAS_NEXT;
 }
 
+static DisasJumpType op_cvdg(DisasContext *s, DisasOps *o)
+{
+    TCGv_i128 t = tcg_temp_new_i128();
+    gen_helper_cvdg(t, o->in1);
+    tcg_gen_qemu_st_i128(t, o->in2, get_mem_index(s), MO_TE | MO_128);
+    return DISAS_NEXT;
+}
+
 static DisasJumpType op_ct(DisasContext *s, DisasOps *o)
 {
     int m3 = get_field(s, m3);
-- 
2.43.0

[PATCH v3 2/4] tests/tcg/s390x: Test CONVERT TO DECIMAL

[Ilya Leoshkevich]

Check the CVD's and CVDG's corner cases.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tests/tcg/s390x/Makefile.target |  1 +
 tests/tcg/s390x/cvd.c           | 45 +++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 tests/tcg/s390x/cvd.c

diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index 30994dcf9c2..04e4bddd83d 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -45,6 +45,7 @@ TESTS+=clc
 TESTS+=laalg
 TESTS+=add-logical-with-carry
 TESTS+=lae
+TESTS+=cvd
 
 cdsg: CFLAGS+=-pthread
 cdsg: LDFLAGS+=-pthread
diff --git a/tests/tcg/s390x/cvd.c b/tests/tcg/s390x/cvd.c
new file mode 100644
index 00000000000..c1fb63ca9a6
--- /dev/null
+++ b/tests/tcg/s390x/cvd.c
@@ -0,0 +1,45 @@
+/*
+ * Test the CONVERT TO DECIMAL instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+static uint64_t cvd(int32_t x)
+{
+    uint64_t ret;
+
+    asm("cvd %[x],%[ret]" : [ret] "=R" (ret) : [x] "r" (x));
+
+    return ret;
+}
+
+static __uint128_t cvdg(int64_t x)
+{
+    __uint128_t ret;
+
+    asm("cvdg %[x],%[ret]" : [ret] "=T" (ret) : [x] "r" (x));
+
+    return ret;
+}
+
+int main(void)
+{
+    __uint128_t m = (((__uint128_t)0x9223372036854775) << 16) | 0x8070;
+
+    assert(cvd(0) == 0xc);
+    assert(cvd(1) == 0x1c);
+    assert(cvd(-1) == 0x1d);
+    assert(cvd(0x7fffffff) == 0x2147483647c);
+    assert(cvd(-0x7fffffff) == 0x2147483647d);
+
+    assert(cvdg(0) == 0xc);
+    assert(cvdg(1) == 0x1c);
+    assert(cvdg(-1) == 0x1d);
+    assert(cvdg(0x7fffffffffffffff) == (m | 0xc));
+    assert(cvdg(-0x7fffffffffffffff) == (m | 0xd));
+
+    return EXIT_SUCCESS;
+}
-- 
2.43.0

[PATCH v3 3/4] target/s390x: implement CVB, CVBY and CVBG

[Ilya Leoshkevich]

From: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>

Convert to Binary - counterparts of the already implemented Convert
to Decimal (CVD*) instructions.
Example from the Principles of Operation: 25594C becomes 63FA.

[iii: Use separate functions for CVB and CVBG for simplicity].

Signed-off-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
---
 target/s390x/helper.h            |  1 +
 target/s390x/tcg/insn-data.h.inc |  4 ++++
 target/s390x/tcg/int_helper.c    | 40 ++++++++++++++++++++++++++++++++
 target/s390x/tcg/translate.c     | 12 ++++++++++
 4 files changed, 57 insertions(+)

diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 332a9a9c632..3c607f4e437 100644
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -88,6 +88,7 @@ DEF_HELPER_FLAGS_3(tcxb, TCG_CALL_NO_RWG_SE, i32, env, i128, i64)
 DEF_HELPER_FLAGS_2(sqeb, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_2(sqdb, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_2(sqxb, TCG_CALL_NO_WG, i128, env, i128)
+DEF_HELPER_FLAGS_3(cvb, TCG_CALL_NO_WG, i64, env, i64, i32)
 DEF_HELPER_FLAGS_1(cvd, TCG_CALL_NO_RWG_SE, i64, s32)
 DEF_HELPER_FLAGS_1(cvdg, TCG_CALL_NO_RWG_SE, i128, s64)
 DEF_HELPER_FLAGS_4(pack, TCG_CALL_NO_WG, void, env, i32, i64, i64)
diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc
index 388dcb8dbbc..9eb998d4c25 100644
--- a/target/s390x/tcg/insn-data.h.inc
+++ b/target/s390x/tcg/insn-data.h.inc
@@ -293,6 +293,10 @@
     D(0xec73, CLFIT,   RIE_a, GIE, r1_32u, i2_16u, 0, 0, ct, 0, 1)
     D(0xec71, CLGIT,   RIE_a, GIE, r1_o, i2_16u, 0, 0, ct, 0, 1)
 
+/* CONVERT TO BINARY */
+    C(0x4f00, CVB,     RX_a,  Z,   la2, 0, new, r1_32, cvb, 0)
+    C(0xe306, CVBY,    RXY_a, LD,  la2, 0, new, r1_32, cvb, 0)
+    C(0xe30e, CVBG,    RXY_a, Z,   la2, 0, r1, 0, cvbg, 0)
 /* CONVERT TO DECIMAL */
     C(0x4e00, CVD,     RX_a,  Z,   r1_o, a2, 0, 0, cvd, 0)
     C(0xe326, CVDY,    RXY_a, LD,  r1_o, a2, 0, 0, cvd, 0)
diff --git a/target/s390x/tcg/int_helper.c b/target/s390x/tcg/int_helper.c
index 121e3006a65..002d4b52dda 100644
--- a/target/s390x/tcg/int_helper.c
+++ b/target/s390x/tcg/int_helper.c
@@ -25,6 +25,7 @@
 #include "exec/exec-all.h"
 #include "qemu/host-utils.h"
 #include "exec/helper-proto.h"
+#include "exec/cpu_ldst.h"
 
 /* #define DEBUG_HELPER */
 #ifdef DEBUG_HELPER
@@ -98,6 +99,45 @@ Int128 HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al, uint64_t b)
     tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
 }
 
+uint64_t HELPER(cvb)(CPUS390XState *env, uint64_t src, uint32_t n)
+{
+    int64_t dec, sign = 0, digit, val = 0, pow10 = 0;
+    const uintptr_t ra = GETPC();
+    uint64_t tmpsrc;
+    int i, j;
+
+    for (i = 0; i < n; i++) {
+        tmpsrc = wrap_address(env, src + (n - i - 1) * 8);
+        dec = cpu_ldq_data_ra(env, tmpsrc, ra);
+        for (j = 0; j < 16; j++, dec >>= 4) {
+            if (i == 0 && j == 0) {
+                sign = dec & 0xf;
+                if (sign < 0xa) {
+                    tcg_s390_data_exception(env, 0, ra);
+                }
+                continue;
+            }
+            digit = dec & 0xf;
+            if (digit > 0x9) {
+                tcg_s390_data_exception(env, 0, ra);
+            }
+            if (i == 0 && j == 1) {
+                if (sign == 0xb || sign == 0xd) {
+                    val = -digit;
+                    pow10 = -10;
+                } else {
+                    val = digit;
+                    pow10 = 10;
+                }
+            } else {
+                val += digit * pow10;
+                pow10 *= 10;
+            }
+        }
+    }
+    return val;
+}
+
 uint64_t HELPER(cvd)(int32_t reg)
 {
     /* positive 0 */
diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
index c2fdc920a50..43216571b44 100644
--- a/target/s390x/tcg/translate.c
+++ b/target/s390x/tcg/translate.c
@@ -2223,6 +2223,18 @@ static DisasJumpType op_csp(DisasContext *s, DisasOps *o)
 }
 #endif
 
+static DisasJumpType op_cvb(DisasContext *s, DisasOps *o)
+{
+    gen_helper_cvb(o->out, tcg_env, o->addr1, tcg_constant_i32(1));
+    return DISAS_NEXT;
+}
+
+static DisasJumpType op_cvbg(DisasContext *s, DisasOps *o)
+{
+    gen_helper_cvb(o->out, tcg_env, o->addr1, tcg_constant_i32(2));
+    return DISAS_NEXT;
+}
+
 static DisasJumpType op_cvd(DisasContext *s, DisasOps *o)
 {
     TCGv_i64 t1 = tcg_temp_new_i64();
-- 
2.43.0

[PATCH v3 4/4] tests/tcg/s390x: Test CONVERT TO BINARY

[Ilya Leoshkevich]

Check the CVB's and CVBG's corner cases.

Co-developed-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tests/tcg/s390x/Makefile.target |  1 +
 tests/tcg/s390x/cvb.c           | 47 +++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)
 create mode 100644 tests/tcg/s390x/cvb.c

diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index 04e4bddd83d..e2aba2ec274 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -46,6 +46,7 @@ TESTS+=laalg
 TESTS+=add-logical-with-carry
 TESTS+=lae
 TESTS+=cvd
+TESTS+=cvb
 
 cdsg: CFLAGS+=-pthread
 cdsg: LDFLAGS+=-pthread
diff --git a/tests/tcg/s390x/cvb.c b/tests/tcg/s390x/cvb.c
new file mode 100644
index 00000000000..47b7a7965f4
--- /dev/null
+++ b/tests/tcg/s390x/cvb.c
@@ -0,0 +1,47 @@
+/*
+ * Test the CONVERT TO DECIMAL instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+static int32_t cvb(uint64_t x)
+{
+    uint32_t ret;
+
+    asm("cvb %[ret],%[x]" : [ret] "=r" (ret) : [x] "R" (x));
+
+    return ret;
+}
+
+static int64_t cvbg(__uint128_t x)
+{
+    int64_t ret;
+
+    asm("cvbg %[ret],%[x]" : [ret] "=r" (ret) : [x] "T" (x));
+
+    return ret;
+}
+
+int main(void)
+{
+    __uint128_t m = (((__uint128_t)0x9223372036854775) << 16) | 0x8070;
+
+    assert(cvb(0xc) == 0);
+    assert(cvb(0x1c) == 1);
+    assert(cvb(0x25594c) == 25594);
+    assert(cvb(0x1d) == -1);
+    assert(cvb(0x2147483647c) == 0x7fffffff);
+    assert(cvb(0x2147483647d) == -0x7fffffff);
+
+    assert(cvbg(0xc) == 0);
+    assert(cvbg(0x1c) == 1);
+    assert(cvbg(0x25594c) == 25594);
+    assert(cvbg(0x1d) == -1);
+    assert(cvbg(m | 0xc) == 0x7fffffffffffffff);
+    assert(cvbg(m | 0xd) == -0x7fffffffffffffff);
+
+    return EXIT_SUCCESS;
+}
-- 
2.43.0

Re: [PATCH v3 2/4] tests/tcg/s390x: Test CONVERT TO DECIMAL

[Thomas Huth]

On 01/02/2024 00.07, Ilya Leoshkevich wrote:
> Check the CVD's and CVDG's corner cases.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/s390x/Makefile.target |  1 +
>   tests/tcg/s390x/cvd.c           | 45 +++++++++++++++++++++++++++++++++
>   2 files changed, 46 insertions(+)
>   create mode 100644 tests/tcg/s390x/cvd.c
> 
> diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
> index 30994dcf9c2..04e4bddd83d 100644
> --- a/tests/tcg/s390x/Makefile.target
> +++ b/tests/tcg/s390x/Makefile.target
> @@ -45,6 +45,7 @@ TESTS+=clc
>   TESTS+=laalg
>   TESTS+=add-logical-with-carry
>   TESTS+=lae
> +TESTS+=cvd
>   
>   cdsg: CFLAGS+=-pthread
>   cdsg: LDFLAGS+=-pthread
> diff --git a/tests/tcg/s390x/cvd.c b/tests/tcg/s390x/cvd.c
> new file mode 100644
> index 00000000000..c1fb63ca9a6
> --- /dev/null
> +++ b/tests/tcg/s390x/cvd.c
> @@ -0,0 +1,45 @@
> +/*
> + * Test the CONVERT TO DECIMAL instruction.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include <assert.h>
> +#include <stdint.h>
> +#include <stdlib.h>
> +
> +static uint64_t cvd(int32_t x)
> +{
> +    uint64_t ret;
> +
> +    asm("cvd %[x],%[ret]" : [ret] "=R" (ret) : [x] "r" (x));
> +
> +    return ret;
> +}
> +
> +static __uint128_t cvdg(int64_t x)
> +{
> +    __uint128_t ret;
> +
> +    asm("cvdg %[x],%[ret]" : [ret] "=T" (ret) : [x] "r" (x));
> +
> +    return ret;
> +}
> +
> +int main(void)
> +{
> +    __uint128_t m = (((__uint128_t)0x9223372036854775) << 16) | 0x8070;
> +
> +    assert(cvd(0) == 0xc);
> +    assert(cvd(1) == 0x1c);
> +    assert(cvd(-1) == 0x1d);
> +    assert(cvd(0x7fffffff) == 0x2147483647c);
> +    assert(cvd(-0x7fffffff) == 0x2147483647d);
> +
> +    assert(cvdg(0) == 0xc);
> +    assert(cvdg(1) == 0x1c);
> +    assert(cvdg(-1) == 0x1d);
> +    assert(cvdg(0x7fffffffffffffff) == (m | 0xc));
> +    assert(cvdg(-0x7fffffffffffffff) == (m | 0xd));
> +
> +    return EXIT_SUCCESS;
> +}

Reviewed-by: Thomas Huth <thuth@redhat.com>

Re: [PATCH v3 4/4] tests/tcg/s390x: Test CONVERT TO BINARY

[Thomas Huth]

On 01/02/2024 00.07, Ilya Leoshkevich wrote:
> Check the CVB's and CVBG's corner cases.
> 
> Co-developed-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/s390x/Makefile.target |  1 +
>   tests/tcg/s390x/cvb.c           | 47 +++++++++++++++++++++++++++++++++
>   2 files changed, 48 insertions(+)
>   create mode 100644 tests/tcg/s390x/cvb.c
> 
> diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
> index 04e4bddd83d..e2aba2ec274 100644
> --- a/tests/tcg/s390x/Makefile.target
> +++ b/tests/tcg/s390x/Makefile.target
> @@ -46,6 +46,7 @@ TESTS+=laalg
>   TESTS+=add-logical-with-carry
>   TESTS+=lae
>   TESTS+=cvd
> +TESTS+=cvb
>   
>   cdsg: CFLAGS+=-pthread
>   cdsg: LDFLAGS+=-pthread
> diff --git a/tests/tcg/s390x/cvb.c b/tests/tcg/s390x/cvb.c
> new file mode 100644
> index 00000000000..47b7a7965f4
> --- /dev/null
> +++ b/tests/tcg/s390x/cvb.c
> @@ -0,0 +1,47 @@
> +/*
> + * Test the CONVERT TO DECIMAL instruction.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include <assert.h>
> +#include <stdint.h>
> +#include <stdlib.h>
> +
> +static int32_t cvb(uint64_t x)
> +{
> +    uint32_t ret;
> +
> +    asm("cvb %[ret],%[x]" : [ret] "=r" (ret) : [x] "R" (x));
> +
> +    return ret;
> +}
> +
> +static int64_t cvbg(__uint128_t x)
> +{
> +    int64_t ret;
> +
> +    asm("cvbg %[ret],%[x]" : [ret] "=r" (ret) : [x] "T" (x));
> +
> +    return ret;
> +}
> +
> +int main(void)
> +{
> +    __uint128_t m = (((__uint128_t)0x9223372036854775) << 16) | 0x8070;
> +
> +    assert(cvb(0xc) == 0);
> +    assert(cvb(0x1c) == 1);
> +    assert(cvb(0x25594c) == 25594);
> +    assert(cvb(0x1d) == -1);
> +    assert(cvb(0x2147483647c) == 0x7fffffff);
> +    assert(cvb(0x2147483647d) == -0x7fffffff);
> +
> +    assert(cvbg(0xc) == 0);
> +    assert(cvbg(0x1c) == 1);
> +    assert(cvbg(0x25594c) == 25594);
> +    assert(cvbg(0x1d) == -1);
> +    assert(cvbg(m | 0xc) == 0x7fffffffffffffff);
> +    assert(cvbg(m | 0xd) == -0x7fffffffffffffff);
> +
> +    return EXIT_SUCCESS;
> +}

Reviewed-by: Thomas Huth <thuth@redhat.com>

Re: [PATCH v3 3/4] target/s390x: implement CVB, CVBY and CVBG

[Thomas Huth]

On 01/02/2024 00.07, Ilya Leoshkevich wrote:
> From: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
> 
> Convert to Binary - counterparts of the already implemented Convert
> to Decimal (CVD*) instructions.
> Example from the Principles of Operation: 25594C becomes 63FA.
> 
> [iii: Use separate functions for CVB and CVBG for simplicity].
> 
> Signed-off-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
> ---
>   target/s390x/helper.h            |  1 +
>   target/s390x/tcg/insn-data.h.inc |  4 ++++
>   target/s390x/tcg/int_helper.c    | 40 ++++++++++++++++++++++++++++++++
>   target/s390x/tcg/translate.c     | 12 ++++++++++
>   4 files changed, 57 insertions(+)
> 
> diff --git a/target/s390x/helper.h b/target/s390x/helper.h
> index 332a9a9c632..3c607f4e437 100644
> --- a/target/s390x/helper.h
> +++ b/target/s390x/helper.h
> @@ -88,6 +88,7 @@ DEF_HELPER_FLAGS_3(tcxb, TCG_CALL_NO_RWG_SE, i32, env, i128, i64)
>   DEF_HELPER_FLAGS_2(sqeb, TCG_CALL_NO_WG, i64, env, i64)
>   DEF_HELPER_FLAGS_2(sqdb, TCG_CALL_NO_WG, i64, env, i64)
>   DEF_HELPER_FLAGS_2(sqxb, TCG_CALL_NO_WG, i128, env, i128)
> +DEF_HELPER_FLAGS_3(cvb, TCG_CALL_NO_WG, i64, env, i64, i32)
>   DEF_HELPER_FLAGS_1(cvd, TCG_CALL_NO_RWG_SE, i64, s32)
>   DEF_HELPER_FLAGS_1(cvdg, TCG_CALL_NO_RWG_SE, i128, s64)
>   DEF_HELPER_FLAGS_4(pack, TCG_CALL_NO_WG, void, env, i32, i64, i64)
> diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc
> index 388dcb8dbbc..9eb998d4c25 100644
> --- a/target/s390x/tcg/insn-data.h.inc
> +++ b/target/s390x/tcg/insn-data.h.inc
> @@ -293,6 +293,10 @@
>       D(0xec73, CLFIT,   RIE_a, GIE, r1_32u, i2_16u, 0, 0, ct, 0, 1)
>       D(0xec71, CLGIT,   RIE_a, GIE, r1_o, i2_16u, 0, 0, ct, 0, 1)
>   
> +/* CONVERT TO BINARY */
> +    C(0x4f00, CVB,     RX_a,  Z,   la2, 0, new, r1_32, cvb, 0)
> +    C(0xe306, CVBY,    RXY_a, LD,  la2, 0, new, r1_32, cvb, 0)
> +    C(0xe30e, CVBG,    RXY_a, Z,   la2, 0, r1, 0, cvbg, 0)
>   /* CONVERT TO DECIMAL */
>       C(0x4e00, CVD,     RX_a,  Z,   r1_o, a2, 0, 0, cvd, 0)
>       C(0xe326, CVDY,    RXY_a, LD,  r1_o, a2, 0, 0, cvd, 0)
> diff --git a/target/s390x/tcg/int_helper.c b/target/s390x/tcg/int_helper.c
> index 121e3006a65..002d4b52dda 100644
> --- a/target/s390x/tcg/int_helper.c
> +++ b/target/s390x/tcg/int_helper.c
> @@ -25,6 +25,7 @@
>   #include "exec/exec-all.h"
>   #include "qemu/host-utils.h"
>   #include "exec/helper-proto.h"
> +#include "exec/cpu_ldst.h"
>   
>   /* #define DEBUG_HELPER */
>   #ifdef DEBUG_HELPER
> @@ -98,6 +99,45 @@ Int128 HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al, uint64_t b)
>       tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
>   }
>   
> +uint64_t HELPER(cvb)(CPUS390XState *env, uint64_t src, uint32_t n)
> +{
> +    int64_t dec, sign = 0, digit, val = 0, pow10 = 0;
> +    const uintptr_t ra = GETPC();
> +    uint64_t tmpsrc;
> +    int i, j;
> +
> +    for (i = 0; i < n; i++) {
> +        tmpsrc = wrap_address(env, src + (n - i - 1) * 8);
> +        dec = cpu_ldq_data_ra(env, tmpsrc, ra);
> +        for (j = 0; j < 16; j++, dec >>= 4) {
> +            if (i == 0 && j == 0) {
> +                sign = dec & 0xf;
> +                if (sign < 0xa) {
> +                    tcg_s390_data_exception(env, 0, ra);
> +                }
> +                continue;
> +            }
> +            digit = dec & 0xf;
> +            if (digit > 0x9) {
> +                tcg_s390_data_exception(env, 0, ra);
> +            }
> +            if (i == 0 && j == 1) {
> +                if (sign == 0xb || sign == 0xd) {
> +                    val = -digit;
> +                    pow10 = -10;
> +                } else {
> +                    val = digit;
> +                    pow10 = 10;
> +                }
> +            } else {
> +                val += digit * pow10;
> +                pow10 *= 10;
> +            }
> +        }
> +    }
> +    return val;
> +}

I just noticed that there was even a v5 of Pavel's patch where David noted 
that the fixed-point-divide exception checks are still missing, see:
 
https://patchwork.kernel.org/project/qemu-devel/patch/20180902003322.3428-4-pavel.zbitskiy@gmail.com/ 


Could you add those, too, please?

  Thanks,
   Thomas

Re: [PATCH v3 4/4] tests/tcg/s390x: Test CONVERT TO BINARY

[Thomas Huth]

On 01/02/2024 00.07, Ilya Leoshkevich wrote:
> Check the CVB's and CVBG's corner cases.
> 
> Co-developed-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/s390x/Makefile.target |  1 +
>   tests/tcg/s390x/cvb.c           | 47 +++++++++++++++++++++++++++++++++
>   2 files changed, 48 insertions(+)
>   create mode 100644 tests/tcg/s390x/cvb.c
> 
> diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
> index 04e4bddd83d..e2aba2ec274 100644
> --- a/tests/tcg/s390x/Makefile.target
> +++ b/tests/tcg/s390x/Makefile.target
> @@ -46,6 +46,7 @@ TESTS+=laalg
>   TESTS+=add-logical-with-carry
>   TESTS+=lae
>   TESTS+=cvd
> +TESTS+=cvb
>   
>   cdsg: CFLAGS+=-pthread
>   cdsg: LDFLAGS+=-pthread
> diff --git a/tests/tcg/s390x/cvb.c b/tests/tcg/s390x/cvb.c
> new file mode 100644
> index 00000000000..47b7a7965f4
> --- /dev/null
> +++ b/tests/tcg/s390x/cvb.c
> @@ -0,0 +1,47 @@
> +/*
> + * Test the CONVERT TO DECIMAL instruction.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include <assert.h>
> +#include <stdint.h>
> +#include <stdlib.h>
> +
> +static int32_t cvb(uint64_t x)
> +{
> +    uint32_t ret;
> +
> +    asm("cvb %[ret],%[x]" : [ret] "=r" (ret) : [x] "R" (x));
> +
> +    return ret;
> +}
> +
> +static int64_t cvbg(__uint128_t x)
> +{
> +    int64_t ret;
> +
> +    asm("cvbg %[ret],%[x]" : [ret] "=r" (ret) : [x] "T" (x));
> +
> +    return ret;
> +}

Just to be on the safe side, could you please add a check for CVBY, too?

  Thanks,
   Thomas