tcg: Add add/sub with carry opcodes and infrastructure

Liveness needs to track carry-live state in order to
determine if the (hidden) output of the opcode is used.
Code generation needs to track carry-live state in order
to avoid clobbering cpu flags when loading constants.

So far, output routines and backends are unchanged.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/tcg/optimize.c b/tcg/optimize.c
index a728a4b2fa..8b00833f97 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1226,6 +1226,12 @@ static bool fold_add_vec(OptContext *ctx, TCGOp *op)
     return finish_folding(ctx, op);
 }
 
+static bool fold_add_carry(OptContext *ctx, TCGOp *op)
+{
+    fold_commutative(ctx, op);
+    return finish_folding(ctx, op);
+}
+
 static bool fold_addsub2(OptContext *ctx, TCGOp *op, bool add)
 {
     bool a_const = arg_is_const(op->args[2]) && arg_is_const(op->args[3]);
@@ -2829,6 +2835,11 @@ void tcg_optimize(TCGContext *s)
         case INDEX_op_add_vec:
             done = fold_add_vec(&ctx, op);
             break;
+        case INDEX_op_addci:
+        case INDEX_op_addco:
+        case INDEX_op_addcio:
+            done = fold_add_carry(&ctx, op);
+            break;
         CASE_OP_32_64(add2):
             done = fold_add2(&ctx, op);
             break;