From 97a878dc6c7b95dd8750bb8ef843f983ded01e95 Mon Sep 17 00:00:00 2001
From: "yu.dongliang" <18588496441@163.com>
Date: Mon, 27 Nov 2023 01:15:49 +0800
Subject: [PATCH] optimize 3ac code of pointer alias

---
 core/scf_basic_block.c             |  4 +-
 core/scf_optimizer_call.c          |  6 ++-
 core/scf_optimizer_pointer_alias.c | 61 +++++++++++++++++++++++++++++-
 3 files changed, 65 insertions(+), 6 deletions(-)

diff --git a/core/scf_basic_block.c b/core/scf_basic_block.c
index a41f99b..36e76a7 100644
--- a/core/scf_basic_block.c
+++ b/core/scf_basic_block.c
@@ -243,8 +243,8 @@ void scf_basic_block_print_list(scf_list_t* h)
 
 			scf_basic_block_t* bb = scf_list_data(l, scf_basic_block_t, list);
 
-			printf("\033[33mbasic_block: %p, index: %d, dfo_normal: %d, cmp_flag: %d, group: %d, loop: %d, dereference_flag: %d, ret_flag: %d\033[0m\n",
-					bb, bb->index, bb->dfo_normal, bb->cmp_flag, bb->group_flag, bb->loop_flag, bb->dereference_flag, bb->ret_flag);
+			printf("\033[33mbasic_block: %p, index: %d, dfo_normal: %d, cmp_flag: %d, call_flag: %d, group: %d, loop: %d, dereference_flag: %d, ret_flag: %d\033[0m\n",
+					bb, bb->index, bb->dfo_normal, bb->cmp_flag, bb->call_flag, bb->group_flag, bb->loop_flag, bb->dereference_flag, bb->ret_flag);
 
 			scf_basic_block_print(bb, sentinel);
 
diff --git a/core/scf_optimizer_call.c b/core/scf_optimizer_call.c
index be0045f..06fd0d5 100644
--- a/core/scf_optimizer_call.c
+++ b/core/scf_optimizer_call.c
@@ -169,8 +169,9 @@ static int __optimize_call_bb(scf_3ac_code_t* c, scf_basic_block_t* bb, scf_list
 				ret = scf_basic_block_split(bb0, &bb1); \
 				if (ret < 0) \
 					return ret; \
-				bb1->call_flag        = 1; \
 				bb1->dereference_flag = bb0->dereference_flag; \
+				bb1->ret_flag         = bb0->ret_flag; \
+				bb0->ret_flag         = 0; \
 				scf_list_add_front(&bb0->list, &bb1->list); \
 				scf_basic_block_mov_code(start, bb1, bb0); \
 			} while (0)
@@ -200,9 +201,11 @@ static int _optimize_call_bb(scf_basic_block_t* bb, scf_list_t* bb_list_head)
 			break;
 
 		if (l != start) {
+			bb->call_flag = 0;
 			SCF_BB_SPLIT_MOV_CODE(l, bb, bb_child);
 			bb = bb_child;
 		}
+		bb->call_flag = 1;
 
 		ret = __optimize_call_bb(c, bb, bb_list_head);
 		if (ret < 0) {
@@ -254,7 +257,6 @@ static int _optimize_call(scf_ast_t* ast, scf_function_t* f, scf_list_t* bb_list
 			return ret;
 	}
 
-//	scf_basic_block_print_list(bb_list_head);
 	ret = 0;
 error:
 	return ret;
diff --git a/core/scf_optimizer_pointer_alias.c b/core/scf_optimizer_pointer_alias.c
index ae24616..31907fd 100644
--- a/core/scf_optimizer_pointer_alias.c
+++ b/core/scf_optimizer_pointer_alias.c
@@ -171,9 +171,46 @@ static int _3ac_pointer_alias(scf_dag_node_t* alias, scf_3ac_code_t* c, scf_basi
 	return 0;
 }
 
+static int _alias_dereference_filter_3ac(scf_dag_node_t* dn, scf_dn_status_t* ds, scf_3ac_code_t* c, scf_basic_block_t* bb, scf_list_t* bb_list_head)
+{
+	scf_3ac_operand_t* dst;
+	scf_3ac_operand_t* src;
+	scf_3ac_code_t*    c2;
+	scf_list_t*        l;
+
+	int i;
+
+	for (l = scf_list_next(&c->list); l != scf_list_sentinel(&bb->code_list_head); l = scf_list_next(l)) {
+		c2 = scf_list_data(l, scf_3ac_code_t, list);
+
+		if (c2->srcs) {
+			for (i = 0; i < c2->srcs->size; i++) {
+				src       = c2->srcs->data[i];
+
+				if (src->dag_node == dn)
+					src->dag_node  = ds->alias;
+			}
+		}
+
+		if (c2->dsts) {
+			for (i = 0; i < c2->dsts->size; i++) {
+				dst       = c2->dsts->data[i];
+
+				if (dst->dag_node == dn)
+					dst->dag_node  = ds->alias;
+			}
+		}
+	}
+
+	return 0;
+}
+
 static int _alias_dereference(scf_vector_t** paliases, scf_dag_node_t* dn_pointer, scf_3ac_code_t* c, scf_basic_block_t* bb, scf_list_t* bb_list_head)
 {
+	scf_3ac_operand_t* dst;
+	scf_dn_status_t*   ds;
 	scf_vector_t*      aliases;
+
 	int ret;
 
 	aliases = scf_vector_alloc();
@@ -187,6 +224,24 @@ static int _alias_dereference(scf_vector_t** paliases, scf_dag_node_t* dn_pointe
 		return ret;
 	}
 
+	if (1 == aliases->size) {
+		ds = aliases->data[0];
+
+		if (SCF_DN_ALIAS_VAR == ds->alias_type) {
+
+			dst = c->dsts->data[0];
+
+			_alias_dereference_filter_3ac(dst->dag_node, ds, c, bb, bb_list_head);
+
+			scf_vector_free(aliases);
+			aliases = NULL;
+
+			if (ret < 0)
+				return ret;
+			return scf_basic_block_inited_vars(bb, bb_list_head);
+		}
+	}
+
 	*paliases = aliases;
 	return 0;
 }
@@ -314,9 +369,10 @@ static int __optimize_alias_bb(scf_list_t** pend, scf_list_t* start, scf_basic_b
 
 	int ret = 0;
 
-	for (l = start; l != *pend; l = scf_list_next(l)) {
+	for (l = start; l != *pend; ) {
 
 		c  = scf_list_data(l, scf_3ac_code_t, list);
+		l  = scf_list_next(l);
 
 		if (!scf_type_is_assign_dereference(c->op->type)
 				&& SCF_OP_DEREFERENCE != c->op->type
@@ -411,7 +467,7 @@ static int __optimize_alias_bb(scf_list_t** pend, scf_list_t* start, scf_basic_b
 		}
 
 		if (flag) {
-			*pend = l;
+			*pend = &c->list;
 			break;
 		}
 	}
@@ -493,6 +549,7 @@ static int _optimize_pointer_alias(scf_ast_t* ast, scf_function_t* f, scf_list_t
 			return ret;
 	}
 
+//	scf_basic_block_print_list(bb_list_head);
 	ret = 0;
 error:
 	return ret;
-- 
2.25.1