target/s390x: Improve ADD LOGICAL WITH CARRY

Now that ADD LOGICAL outputs carry, we can use that as input directly.
It also means we can re-use CC_OP_ADDU and produce an output carry
directly from ADD LOGICAL WITH CARRY.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201214221356.68039-3-richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 30 insertions, 33 deletions

diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index b473233edf..d1d97e4696 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -600,12 +600,10 @@ static void gen_op_calc_cc(DisasContext *s)
         dummy = tcg_const_i64(0);
         /* FALLTHRU */
     case CC_OP_ADD_64:
-    case CC_OP_ADDC_64:
     case CC_OP_SUB_64:
     case CC_OP_SUBU_64:
     case CC_OP_SUBB_64:
     case CC_OP_ADD_32:
-    case CC_OP_ADDC_32:
     case CC_OP_SUB_32:
     case CC_OP_SUBU_32:
     case CC_OP_SUBB_32:
@@ -665,12 +663,10 @@ static void gen_op_calc_cc(DisasContext *s)
         gen_helper_calc_cc(cc_op, cpu_env, local_cc_op, cc_src, cc_dst, dummy);
         break;
     case CC_OP_ADD_64:
-    case CC_OP_ADDC_64:
     case CC_OP_SUB_64:
     case CC_OP_SUBU_64:
     case CC_OP_SUBB_64:
     case CC_OP_ADD_32:
-    case CC_OP_ADDC_32:
     case CC_OP_SUB_32:
     case CC_OP_SUBU_32:
     case CC_OP_SUBB_32:
@@ -1443,30 +1439,41 @@ static DisasJumpType op_addu64(DisasContext *s, DisasOps *o)
     return DISAS_NEXT;
 }
 
-static DisasJumpType op_addc(DisasContext *s, DisasOps *o)
+/* Compute carry into cc_src. */
+static void compute_carry(DisasContext *s)
 {
-    DisasCompare cmp;
-    TCGv_i64 carry;
+    switch (s->cc_op) {
+    case CC_OP_ADDU:
+        /* The carry value is already in cc_src (1,0). */
+        break;
+    default:
+        gen_op_calc_cc(s);
+        /* fall through */
+    case CC_OP_STATIC:
+        /* The carry flag is the msb of CC; compute into cc_src. */
+        tcg_gen_extu_i32_i64(cc_src, cc_op);
+        tcg_gen_shri_i64(cc_src, cc_src, 1);
+        break;
+    }
+}
 
+static DisasJumpType op_addc32(DisasContext *s, DisasOps *o)
+{
+    compute_carry(s);
     tcg_gen_add_i64(o->out, o->in1, o->in2);
+    tcg_gen_add_i64(o->out, o->out, cc_src);
+    return DISAS_NEXT;
+}
 
-    /* The carry flag is the msb of CC, therefore the branch mask that would
-       create that comparison is 3.  Feeding the generated comparison to
-       setcond produces the carry flag that we desire.  */
-    disas_jcc(s, &cmp, 3);
-    carry = tcg_temp_new_i64();
-    if (cmp.is_64) {
-        tcg_gen_setcond_i64(cmp.cond, carry, cmp.u.s64.a, cmp.u.s64.b);
-    } else {
-        TCGv_i32 t = tcg_temp_new_i32();
-        tcg_gen_setcond_i32(cmp.cond, t, cmp.u.s32.a, cmp.u.s32.b);
-        tcg_gen_extu_i32_i64(carry, t);
-        tcg_temp_free_i32(t);
-    }
-    free_compare(&cmp);
+static DisasJumpType op_addc64(DisasContext *s, DisasOps *o)
+{
+    compute_carry(s);
+
+    TCGv_i64 zero = tcg_const_i64(0);
+    tcg_gen_add2_i64(o->out, cc_src, o->in1, zero, cc_src, zero);
+    tcg_gen_add2_i64(o->out, cc_src, o->out, cc_src, o->in2, zero);
+    tcg_temp_free_i64(zero);
 
-    tcg_gen_add_i64(o->out, o->out, carry);
-    tcg_temp_free_i64(carry);
     return DISAS_NEXT;
 }
 
@@ -5217,16 +5224,6 @@ static void cout_addu64(DisasContext *s, DisasOps *o)
     gen_op_update2_cc_i64(s, CC_OP_ADDU, cc_src, o->out);
 }
 
-static void cout_addc32(DisasContext *s, DisasOps *o)
-{
-    gen_op_update3_cc_i64(s, CC_OP_ADDC_32, o->in1, o->in2, o->out);
-}
-
-static void cout_addc64(DisasContext *s, DisasOps *o)
-{
-    gen_op_update3_cc_i64(s, CC_OP_ADDC_64, o->in1, o->in2, o->out);
-}
-
 static void cout_cmps32(DisasContext *s, DisasOps *o)
 {
     gen_op_update2_cc_i64(s, CC_OP_LTGT_32, o->in1, o->in2);