From e875e4e7f3716aa268ffbbf55ee199ec82b6aeba Mon Sep 17 00:00:00 2001
From: Mingchuan Wu <wumingchuan1992@foxmail.com>
Date: Thu, 21 Dec 2023 15:50:34 +0800
Subject: [PATCH 2/2] [DFE] Add escape check. Fields with escape risks should
 not be processed.

---
 gcc/ipa-struct-reorg/ipa-struct-reorg.c  | 15 +++++--
 gcc/testsuite/gcc.dg/struct/dfe_escape.c | 50 ++++++++++++++++++++++++
 2 files changed, 62 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/struct/dfe_escape.c

diff --git a/gcc/ipa-struct-reorg/ipa-struct-reorg.c b/gcc/ipa-struct-reorg/ipa-struct-reorg.c
index 0064811ac..dcfa7cd95 100644
--- a/gcc/ipa-struct-reorg/ipa-struct-reorg.c
+++ b/gcc/ipa-struct-reorg/ipa-struct-reorg.c
@@ -444,8 +444,13 @@ srtype::has_dead_field (void)
       if (!(this_field->field_access & READ_FIELD)
 	 && !FUNCTION_POINTER_TYPE_P (this_field->fieldtype))
 	{
-	  may_dfe = true;
-	  break;
+	  /* Fields with escape risks should not be processed. */
+	  if (this_field->type == NULL
+	      || (this_field->type->escapes == does_not_escape))
+	    {
+	      may_dfe = true;
+	      break;
+	    }
 	}
     }
   return may_dfe;
@@ -1030,7 +1035,11 @@ srtype::create_new_type (void)
       if (current_layout_opt_level & DEAD_FIELD_ELIMINATION
 	  && !(f->field_access & READ_FIELD)
 	  && !FUNCTION_POINTER_TYPE_P (f->fieldtype))
-	continue;
+	{
+	  /* Fields with escape risks should not be processed. */
+	  if (f->type == NULL || (f->type->escapes == does_not_escape))
+	    continue;
+	}
       f->create_new_fields (newtype, newfields, newlast);
     }
 
diff --git a/gcc/testsuite/gcc.dg/struct/dfe_escape.c b/gcc/testsuite/gcc.dg/struct/dfe_escape.c
new file mode 100644
index 000000000..1b143cd26
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/struct/dfe_escape.c
@@ -0,0 +1,50 @@
+/* { dg-do compile } */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct arc arc_t;
+typedef struct arc *arc_p;
+
+typedef struct network
+{    
+  int x;
+} network_t;
+
+struct arc
+{
+  int flow;
+  network_t* net_add;
+};
+
+const int MAX = 100;
+
+/* let it escape_array, "Type is used in an array [not handled yet]".  */
+network_t* net[2];
+arc_p stop_arcs = NULL;
+
+int
+main ()
+{
+  net[0] = (network_t*) calloc (1, sizeof(network_t));
+  stop_arcs = (arc_p) calloc (MAX, sizeof (arc_t));
+
+  net[0]->x = 100;
+
+  for (unsigned i = 0; i < 3; i++)
+    {        
+      net[0]->x = net[0]->x + 2;
+      stop_arcs->flow = net[0]->x / 2;
+      stop_arcs->flow = stop_arcs->flow + 20;
+      stop_arcs->net_add = net[0];
+      stop_arcs++;
+    }
+
+  if( net[1] != 0 && stop_arcs != 0)
+    {
+      return -1;
+    }
+  return 0;
+}
+
+/* { dg-final { scan-ipa-dump-times "Dead field elimination" 0 "struct_reorg" } } */
-- 
2.33.0