Perform actual constant folding for ADD, SUB and MUL operations.
Signed-off-by: Kirill Batuzov <batuz...@ispras.ru>
---
tcg/optimize.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 102 insertions(+), 0 deletions(-)
diff --git a/tcg/optimize.c b/tcg/optimize.c
index a761c51..4073f05 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -82,6 +82,79 @@ static void reset_temp(tcg_temp_state *state,
tcg_target_ulong *vals,
state[temp] = TCG_TEMP_ANY;
}
+static int op_bits(int op)
+{
+ switch (op) {
+ case INDEX_op_mov_i32:
+ case INDEX_op_add_i32:
+ case INDEX_op_sub_i32:
+ case INDEX_op_mul_i32:
+ return 32;
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_mov_i64:
+ case INDEX_op_add_i64:
+ case INDEX_op_sub_i64:
+ case INDEX_op_mul_i64:
+ return 64;
+#endif
+ default:
+ fprintf(stderr, "Unrecognized operation %d in op_bits.\n", op);
+ tcg_abort();
+ }
+}
+
+static int op_to_movi(int op)
+{
+ if (op_bits(op) == 32) {
+ return INDEX_op_movi_i32;
+ }
+#if TCG_TARGET_REG_BITS == 64
+ if (op_bits(op) == 64) {
+ return INDEX_op_movi_i64;
+ }
+#endif
+ tcg_abort();
+}
+
+static TCGArg do_constant_folding_2(int op, TCGArg x, TCGArg y)
+{
+ switch (op) {
+ case INDEX_op_add_i32:
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_add_i64:
+#endif
+ return x + y;
+
+ case INDEX_op_sub_i32:
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_sub_i64:
+#endif
+ return x - y;
+
+ case INDEX_op_mul_i32:
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_mul_i64:
+#endif
+ return x * y;
+
+ default:
+ fprintf(stderr,
+ "Unrecognized operation %d in do_constant_folding.\n", op);
+ tcg_abort();
+ }
+}
+
+static TCGArg do_constant_folding(int op, TCGArg x, TCGArg y)
+{
+ TCGArg res = do_constant_folding_2(op, x, y);
+#if TCG_TARGET_REG_BITS == 64
+ if (op_bits(op) == 32) {
+ res &= 0xffffffff;
+ }
+#endif
+ return res;
+}
+
/* Propagate constants and copies, fold constant expressions. */
static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
TCGArg *args, TCGOpDef *tcg_op_defs)
@@ -164,6 +237,35 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
uint16_t *tcg_opc_ptr,
gen_args += 2;
args += 2;
break;
+ case INDEX_op_add_i32:
+ case INDEX_op_sub_i32:
+ case INDEX_op_mul_i32:
+#if TCG_TARGET_REG_BITS == 64
+ case INDEX_op_add_i64:
+ case INDEX_op_sub_i64:
+ case INDEX_op_mul_i64:
+#endif
+ if (state[args[1]] == TCG_TEMP_CONST
+ && state[args[2]] == TCG_TEMP_CONST) {
+ gen_opc_buf[op_index] = op_to_movi(op);
+ gen_args[0] = args[0];
+ gen_args[1] =
+ do_constant_folding(op, vals[args[1]], vals[args[2]]);
+ reset_temp(state, vals, gen_args[0], nb_temps, nb_globals);
+ state[gen_args[0]] = TCG_TEMP_CONST;
+ vals[gen_args[0]] = gen_args[1];
+ gen_args += 2;
+ args += 3;
+ break;
+ } else {
+ reset_temp(state, vals, args[0], nb_temps, nb_globals);
+ gen_args[0] = args[0];
+ gen_args[1] = args[1];
+ gen_args[2] = args[2];
+ gen_args += 3;
+ args += 3;
+ break;
+ }
case INDEX_op_call:
case INDEX_op_jmp:
case INDEX_op_br:
--
1.7.4.1
