s390x/tcg: Implement VECTOR FP ADD

1. We'll reuse op_vfa() for similar instructions later, prepare for
   that.
2. We'll reuse vop64_3() for other instructions later.
3. Take care of modifying the vector register only if no trap happened.
 - on traps, flags are not updated and no elements are modified
 - traps don't modify the fpc flags
 - without traps, all exceptions of all elements are merged
4. We'll reuse check_ieee_exc() later when we need the XxC flag.

We have to check for exceptions after processing each element.
Provide separate handlers for single/all element processing. We'll do
the same for all applicable FP instructions.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/target/s390x/translate_vx.inc.c b/target/s390x/translate_vx.inc.c
index f26ffa2895..44da9f2645 100644
--- a/target/s390x/translate_vx.inc.c
+++ b/target/s390x/translate_vx.inc.c
@@ -52,6 +52,11 @@
 #define ES_64   MO_64
 #define ES_128  4
 
+/* Floating-Point Format */
+#define FPF_SHORT       2
+#define FPF_LONG        3
+#define FPF_EXT         4
+
 static inline bool valid_vec_element(uint8_t enr, TCGMemOp es)
 {
     return !(enr & ~(NUM_VEC_ELEMENTS(es) - 1));
@@ -2538,3 +2543,27 @@ static DisasJumpType op_vstrc(DisasContext *s, DisasOps *o)
     }
     return DISAS_NEXT;
 }
+
+static DisasJumpType op_vfa(DisasContext *s, DisasOps *o)
+{
+    const uint8_t fpf = get_field(s->fields, m4);
+    const uint8_t m5 = get_field(s->fields, m5);
+    const bool se = extract32(m5, 3, 1);
+    gen_helper_gvec_3_ptr *fn;
+
+    if (fpf != FPF_LONG || extract32(m5, 0, 3)) {
+        gen_program_exception(s, PGM_SPECIFICATION);
+        return DISAS_NORETURN;
+    }
+
+    switch (s->fields->op2) {
+    case 0xe3:
+        fn = se ? gen_helper_gvec_vfa64s : gen_helper_gvec_vfa64;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+    gen_gvec_3_ptr(get_field(s->fields, v1), get_field(s->fields, v2),
+                   get_field(s->fields, v3), cpu_env, 0, fn);
+    return DISAS_NEXT;
+}