target/s390x: Improve cc computation for ADD LOGICAL

The resulting cc is only dependent on the result and the
carry-out.  So save those things rather than the inputs.

Carry-out for 64-bit inputs is had via tcg_gen_add2_i64 directly
into cc_src.  Carry-out for 32-bit inputs is had via extraction
from a normal 64-bit add (with zero-extended inputs).

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201214221356.68039-2-richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 9 insertions, 16 deletions

diff --git a/target/s390x/cc_helper.c b/target/s390x/cc_helper.c
index 5432aeeed4..59da4d1cc2 100644
--- a/target/s390x/cc_helper.c
+++ b/target/s390x/cc_helper.c
@@ -123,6 +123,12 @@ static uint32_t cc_calc_nz(uint64_t dst)
     return !!dst;
 }
 
+static uint32_t cc_calc_addu(uint64_t carry_out, uint64_t result)
+{
+    g_assert(carry_out <= 1);
+    return (result != 0) + 2 * carry_out;
+}
+
 static uint32_t cc_calc_add_64(int64_t a1, int64_t a2, int64_t ar)
 {
     if ((a1 > 0 && a2 > 0 && ar < 0) || (a1 < 0 && a2 < 0 && ar > 0)) {
@@ -138,11 +144,6 @@ static uint32_t cc_calc_add_64(int64_t a1, int64_t a2, int64_t ar)
     }
 }
 
-static uint32_t cc_calc_addu_64(uint64_t a1, uint64_t a2, uint64_t ar)
-{
-    return (ar != 0) + 2 * (ar < a1);
-}
-
 static uint32_t cc_calc_addc_64(uint64_t a1, uint64_t a2, uint64_t ar)
 {
     /* Recover a2 + carry_in.  */
@@ -239,11 +240,6 @@ static uint32_t cc_calc_add_32(int32_t a1, int32_t a2, int32_t ar)
     }
 }
 
-static uint32_t cc_calc_addu_32(uint32_t a1, uint32_t a2, uint32_t ar)
-{
-    return (ar != 0) + 2 * (ar < a1);
-}
-
 static uint32_t cc_calc_addc_32(uint32_t a1, uint32_t a2, uint32_t ar)
 {
     /* Recover a2 + carry_in.  */
@@ -483,12 +479,12 @@ static uint32_t do_calc_cc(CPUS390XState *env, uint32_t cc_op,
     case CC_OP_NZ:
         r =  cc_calc_nz(dst);
         break;
+    case CC_OP_ADDU:
+        r = cc_calc_addu(src, dst);
+        break;
     case CC_OP_ADD_64:
         r =  cc_calc_add_64(src, dst, vr);
         break;
-    case CC_OP_ADDU_64:
-        r =  cc_calc_addu_64(src, dst, vr);
-        break;
     case CC_OP_ADDC_64:
         r =  cc_calc_addc_64(src, dst, vr);
         break;
@@ -517,9 +513,6 @@ static uint32_t do_calc_cc(CPUS390XState *env, uint32_t cc_op,
     case CC_OP_ADD_32:
         r =  cc_calc_add_32(src, dst, vr);
         break;
-    case CC_OP_ADDU_32:
-        r =  cc_calc_addu_32(src, dst, vr);
-        break;
     case CC_OP_ADDC_32:
         r =  cc_calc_addc_32(src, dst, vr);
         break;