can deal with arrays

21 files changed, 291 insertions, 147 deletions

diff --git a/gcc/expr-rewriter.c b/gcc/expr-rewriter.c
index 616271d96c7..6ea2b42c580 100644
--- a/gcc/expr-rewriter.c
+++ b/gcc/expr-rewriter.c
@@ -13,16 +13,16 @@ ExprTypeRewriter::_walk_post(const_tree e)
 
   tree r_t = _map[t];
   TREE_TYPE((tree)e) = r_t;
-  TypeStringifier stringifer;
-  const std::string t_name = stringifer.stringify(t);
-  const std::string r_t_name = stringifer.stringify(r_t);
-  log("replacing %s with %s\n", t_name.c_str(), r_t_name.c_str());
+  //TypeStringifier stringifer;
+  //const std::string r_t_name = stringifer.stringify(r_t);
+  //const std::string t_name = stringifer.stringify(t);
+  //log("replacing %s with %s\n", t_name.c_str(), r_t_name.c_str());
 }
 
 void
 ExprTypeRewriter::_walk_COMPONENT_REF_post(const_tree e)
 {
-  // TODO: I need to rewrite the field 
+
   const_tree f = TREE_OPERAND(e, 1);
   // So, what we need is a map between this field and the new field
   const bool in_map = _map2.find(f) != _map2.end();
diff --git a/gcc/expr-walker.c b/gcc/expr-walker.c
index 6f219f02f78..a86fde979b3 100644
--- a/gcc/expr-walker.c
+++ b/gcc/expr-walker.c
@@ -108,7 +108,7 @@ ExprWalker::_walk(const_tree e)
     default:
     {
       log("missing %s\n", get_tree_code_name(code));
-      //gcc_unreachable();
+      gcc_unreachable();
     }
     break;
   }
@@ -119,9 +119,11 @@ void \
 ExprWalker::walk_ ## code (const_tree e) \
 { \
   assert_is_type(e, code); \
+  _walk_pre(e); \
   _walk_ ## code ## _pre (e); \
   _walk_ ## code (e); \
   _walk_ ## code ## _post (e); \
+  _walk_post(e); \ 
 }
 
 ExprWalkerFuncDef(CONSTRUCTOR)
@@ -157,7 +159,7 @@ ExprWalker::_walk_op_n(const_tree e, unsigned n)
   gcc_assert(e);
   const_tree op_n = TREE_OPERAND(e, n);
   gcc_assert(op_n);
-  _walk(op_n);
+  walk(op_n);
 }
 
 void
diff --git a/gcc/gimple-escaper.c b/gcc/gimple-escaper.c
index 82e41d0490e..b683a7c4d1b 100644
--- a/gcc/gimple-escaper.c
+++ b/gcc/gimple-escaper.c
@@ -27,6 +27,7 @@
 #include "cfg.h" // needed for gimple-iterator.h
 #include "gimple-iterator.h"
 #include "gimple-ssa.h"
+#include "gimple-pretty-print.h"
 #include <stdbool.h>
 
 #include "gimple-escaper.hpp"
@@ -238,7 +239,7 @@ GimpleEscaper::_walk_pre(gcall *s)
   {
     const_tree a = gimple_call_arg(s, i);
     gcc_assert(a);
-    exprEscaper.update(a, arg_reason);
+    exprEscaper.update_single_level(a, arg_reason);
   }
 
   const_tree lhs = gimple_call_lhs(s);
diff --git a/gcc/gimple-walker.c b/gcc/gimple-walker.c
index e61b49f0a98..c9dd51fb810 100644
--- a/gcc/gimple-walker.c
+++ b/gcc/gimple-walker.c
@@ -208,7 +208,7 @@ GimpleWalker::_walk(gimple *stmt)
   }
   const char* name = gimple_code_name[code];
   log("gimple code name %s\n", name);
- // gcc_unreachable();
+  gcc_unreachable();
 }
 
 #define GimpleWalkerFuncDef(type) \
diff --git a/gcc/ipa-type-escape-analysis.c b/gcc/ipa-type-escape-analysis.c
index f17dd5ded9e..fe48b552997 100644
--- a/gcc/ipa-type-escape-analysis.c
+++ b/gcc/ipa-type-escape-analysis.c
@@ -278,9 +278,11 @@ collect_types()
   TypeReconstructor reconstructor(record_field_offset_map);
   TypeStringifier stringifier;
 
-  for (auto i = record_field_offset_map.cbegin(), e = record_field_offset_map.cend(); i != e; ++i)
+  for (auto i = types.points_to_record.cbegin(), e = types.points_to_record.cend(); i != e; ++i)
   {
-    const_tree record = i->first;
+    const_tree record = *i;
+    std::string name_from = stringifier.stringify(record);
+    log("%s\n", name_from.c_str());
     reconstructor.walk(record);
   }
 
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-field-reads-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-field-reads-0.c
new file mode 100644
index 00000000000..18e8fe0a596
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-field-reads-0.c
@@ -0,0 +1,20 @@
+/* { dg-do run } */
+/* { dg-options  "-flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+int
+main ()
+{
+  struct astruct_s
+  {
+    _Bool a;
+    _Bool b;
+    _Bool c;
+  };
+  struct astruct_s astruct;
+  _Bool a = astruct.a;
+  _Bool c = astruct.c;
+  return 0;
+}
+
+/* { dg-final { scan-ipa-dump "replacing field a 0 with a 0" "type-escape-analysis" } } */
+/* { dg-final { scan-ipa-dump "replacing field c 16 with a 8" "type-escape-analysis" } } */
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-rewrite-local-decl-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-rewrite-local-decl-0.c
new file mode 100644
index 00000000000..13aa56ed9ee
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-05-rewrite-local-decl-0.c
@@ -0,0 +1,23 @@
+/* { dg-do run } */
+/* { dg-options  "-flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+#include <stdio.h>
+
+int
+main ()
+{
+  struct astruct_s
+  {
+    _Bool a;
+    _Bool b;
+    _Bool c;
+  };
+  struct astruct_s astruct;
+  printf("%d %d\n", astruct.a, astruct.c);
+  return 0;
+}
+
+// This is different from previous because here we are replacing a local declaration
+/* { dg-final { scan-ipa-dump "replacing field a 0 with a 0" "type-escape-analysis" } } */
+/* { dg-final { scan-ipa-dump "replacing field c 16 with c 8" "type-escape-analysis" } } */
+
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-06-field-writes-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-06-field-writes-0.c
new file mode 100644
index 00000000000..41396bfe4d3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-06-field-writes-0.c
@@ -0,0 +1,24 @@
+/* { dg-do run } */
+/* { dg-options  "-flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+#include <stdio.h>
+
+int
+main ()
+{
+  struct astruct_s
+  {
+    _Bool a;
+    _Bool b;
+    _Bool c;
+  };
+  struct astruct_s astruct;
+  astruct.c = 0;
+  printf("%d %d\n", astruct.a, astruct.c);
+  return 0;
+}
+
+/* { dg-final { scan-ipa-dump "replacing field a 0 with a 0" "type-escape-analysis" } } */
+// There's two... mmm.. not sure how to convey this here to the test
+/* { dg-final { scan-ipa-dump "replacing field c 16 with c 8" "type-escape-analysis" } } */
+/* { dg-final { scan-ipa-dump "replacing field c 16 with c 8" "type-escape-analysis" } } */
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-07-delete-first-field-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-07-delete-first-field-0.c
new file mode 100644
index 00000000000..a9c40ba0eda
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-07-delete-first-field-0.c
@@ -0,0 +1,23 @@
+/* { dg-do run } */
+/* { dg-options  "-w -flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+#include <assert.h>
+#include <stdio.h>
+
+int
+main ()
+{
+  struct astruct_s
+  {
+    _Bool b;
+    _Bool a;
+    _Bool c;
+    _Bool d;
+  };
+  struct astruct_s astruct;
+
+  printf("%d %d %d\n", astruct.a, astruct.c, astruct.d);
+  _Bool *a_ptr = &astruct.a;
+  struct astruct_s *s_ptr = &astruct;
+  assert(a_ptr == s_ptr);
+}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-08-modify-double-struct-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-08-modify-double-struct-0.c
new file mode 100644
index 00000000000..0706c7b22ea
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-08-modify-double-struct-0.c
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+/* { dg-options  "-flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+#include <assert.h>
+int
+main ()
+{
+  struct inner_s
+  {
+    _Bool a;
+    _Bool b;
+    _Bool c;
+    _Bool d;
+  };
+  struct astruct_s
+  {
+    struct inner_s a;
+    struct inner_s b;
+    struct inner_s c;
+    struct inner_s d;
+  };
+  struct astruct_s astruct;
+  struct inner_s *a_ptr = &(astruct.a);
+  struct inner_s *c_ptr = &(astruct.c);
+  struct inner_s *d_ptr = &(astruct.d);
+  struct inner_s *c_ptr_2 = a_ptr + 1;
+  struct inner_s *a_ptr_2 = d_ptr - 2;
+  assert(c_ptr_2 == c_ptr);
+  assert(a_ptr == a_ptr_2);
+}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-09-modify-int-struct-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-09-modify-int-struct-0.c
new file mode 100644
index 00000000000..e5e80860034
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-09-modify-int-struct-0.c
@@ -0,0 +1,22 @@
+/* { dg-do run } */
+/* { dg-options  "-flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis " } */
+
+#include <assert.h>
+
+int
+main ()
+{
+  struct astruct_s
+  {
+    int a;
+    int b;
+    int c;
+    int d;
+  };
+  struct astruct_s astruct;
+  int *a = &(astruct.a);
+  int *c = &(astruct.c);
+  int *d = &(astruct.d);
+  assert (c - 1 == a);
+  assert (a + 2 == d);
+}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-10-array-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-10-array-0.c
index af0c175515a..8e828b8c6ed 100644
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-10-array-0.c
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-10-array-0.c
@@ -1,5 +1,8 @@
 /* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
+/* { dg-options  " -flto -fipa-type-escape-analysis -fdump-ipa-type-escape-analysis" } */
+
+#include <assert.h>
+#include <stdio.h>
 
 int
 main ()
@@ -11,6 +14,10 @@ main ()
     _Bool c;
   };
   struct astruct_s a;
+  printf("%d %d\n", a.a, a.c);
   struct astruct_s b[2];
   a = b[0];
+  _Bool *a_ptr = &a.a;
+  _Bool *c_ptr = &a.c;
+  assert(a_ptr + 1 == c_ptr);
 }
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-field-reads-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-field-reads-0.c
deleted file mode 100644
index 3e37a780774..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-field-reads-0.c
+++ /dev/null
@@ -1,18 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-int
-main ()
-{
-  struct astruct_s
-  {
-    _Bool a;
-    _Bool b;
-    _Bool c;
-  };
-  struct astruct_s astruct;
-  _Bool c = astruct.c;
-  return 0;
-}
-
-/* "rewrite,field_offset,c,1" "typelist" } } */
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-rewrite-local-decl-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-rewrite-local-decl-0.c
deleted file mode 100644
index 07d6ea35e0f..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-5-rewrite-local-decl-0.c
+++ /dev/null
@@ -1,15 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-int
-main ()
-{
-  struct astruct_s
-  {
-    _Bool a;
-    _Bool b;
-    _Bool c;
-  };
-  struct astruct_s astruct;
-  return 0;
-}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-6-field-writes-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-6-field-writes-0.c
deleted file mode 100644
index c7092516692..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-6-field-writes-0.c
+++ /dev/null
@@ -1,16 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-int
-main ()
-{
-  struct astruct_s
-  {
-    _Bool a;
-    _Bool b;
-    _Bool c;
-  };
-  struct astruct_s astruct;
-  astruct.c = 0;
-  return 0;
-}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-7-delete-first-field-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-7-delete-first-field-0.c
deleted file mode 100644
index b0fdc15d63e..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-7-delete-first-field-0.c
+++ /dev/null
@@ -1,23 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-#include <assert.h>
-
-int
-main ()
-{
-  struct astruct_s
-  {
-    _Bool b;
-    _Bool a;
-    _Bool c;
-    _Bool d;
-  };
-  struct astruct_s astruct;
-
-  _Bool *a_ptr = &astruct.a;
-  struct astruct_s *astruct_ptr = &astruct;
-  _Bool test = (_Bool *) astruct_ptr == a_ptr;
-  char compile_test[test ? 1 : -1];
-  assert (test);
-}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-8-modify-double-struct-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-8-modify-double-struct-0.c
deleted file mode 100644
index 83c508ee24e..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-8-modify-double-struct-0.c
+++ /dev/null
@@ -1,33 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-#include <assert.h>
-int
-main ()
-{
-  struct inner_s
-  {
-    _Bool a;
-    _Bool b;
-    _Bool c;
-    _Bool d;
-  };
-  struct astruct_s
-  {
-    struct inner_s a;
-    struct inner_s b;
-    struct inner_s c;
-    struct inner_s d;
-  };
-  struct astruct_s astruct;
-  struct inner_s a = astruct.a;
-  struct inner_s c = astruct.c;
-  struct inner_s d = astruct.d;
-  _Bool *pa = (_Bool *) &(astruct.a);
-  _Bool *pc = (_Bool *) &(astruct.c);
-  _Bool *pd = (_Bool *) &(astruct.d);
-  _Bool *c_1 = pa + 4;
-  _Bool *d_1 = pa + 8;
-  assert (pc == c_1);
-  assert (pd == d_1);
-}
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-9-modify-int-struct-0.c b/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-9-modify-int-struct-0.c
deleted file mode 100644
index be51f9e06e9..00000000000
--- a/gcc/testsuite/gcc.dg/ipa/ipa-structreorg-9-modify-int-struct-0.c
+++ /dev/null
@@ -1,18 +0,0 @@
-/* { dg-do run } */
-/* { dg-options  "-flto -flto-partition=none -fipa-dead-field-eliminate -fdump-ipa-structure-reorg -fipa-typelist-field=b -fipa-typelist-struct=astruct_s" } */
-
-int
-main ()
-{
-  struct astruct_s
-  {
-    int a;
-    int b;
-    int c;
-    int d;
-  };
-  struct astruct_s astruct;
-  int a = astruct.a;
-  int c = astruct.c;
-  int d = astruct.d;
-}
diff --git a/gcc/type-escaper.c b/gcc/type-escaper.c
index edfb55eb44b..ef81af37589 100644
--- a/gcc/type-escaper.c
+++ b/gcc/type-escaper.c
@@ -36,17 +36,15 @@
 bool
 TypeEscaper::is_memoized(const_tree t)
 {
-	/*
   const bool in_set = calc.find(t) != calc.end();
   if (!in_set) return false;
 
-  const bool will_not_escape = !_reason.is_escaping;
+  const bool will_not_escape = !_reason.is_escaping();
   if (will_not_escape) return true;
 
-  const bool already_escaping = in_set && calc[t].is_escaping;
+  const bool already_escaping = in_set && calc[t].is_escaping();
   if (already_escaping) return true;
 
-  */
   return false;
 }
 
diff --git a/gcc/type-reconstructor.c b/gcc/type-reconstructor.c
index ac3cb8b6e2e..26796eacf2b 100644
--- a/gcc/type-reconstructor.c
+++ b/gcc/type-reconstructor.c
@@ -34,6 +34,50 @@
 #include "type-stringifier.hpp"
 #include "stor-layout.h"
 
+void
+TypeReconstructor::set_is_not_modified_yet(const_tree t)
+{
+  gcc_assert(t);
+  const bool is_in_reorg_map = _reorg_map.find(t) != _reorg_map.end();
+  modified_map[t] = false;
+
+  const_tree tt = TREE_TYPE(t);
+  if (!tt) return;
+
+  const bool is_in_reorg_map_2 = _reorg_map.find(tt) != _reorg_map.end();
+  if (!is_in_reorg_map_2) return;
+  log("is in reorg map\n");
+
+  tree type = _reorg_map[tt];
+  log("name = %s\n", TypeStringifier::get_type_identifier(type).c_str());
+  const bool is_modified = strstr(TypeStringifier::get_type_identifier(type).c_str(), ".reorg");
+  if (!is_modified) return;
+
+  mark_all_pointing_here_as_modified();
+
+}
+
+void
+TypeReconstructor::mark_all_pointing_here_as_modified()
+{
+  for (auto i = modified_map.begin(), e = modified_map.end(); i != e; ++i)
+  {
+    const_tree type = i->first;
+    i->second = true;
+  }
+}
+
+bool
+TypeReconstructor::get_is_modified(const_tree t)
+{
+  gcc_assert(t);
+  const bool in_map = modified_map.find(t) != modified_map.end();
+  gcc_assert(in_map);
+  bool retval = modified_map[t];
+  modified_map.erase(t);
+  return retval;
+}
+
 bool
 TypeReconstructor::is_memoized(const_tree t)
 {
@@ -73,30 +117,74 @@ get_new_identifier(const_tree type)
 void
 TypeReconstructor::_walk_ARRAY_TYPE_pre(const_tree t)
 {
+  for_reference.push(t);
+  set_is_not_modified_yet(t);
+
+  tree copy = build_variant_type_copy((tree) t);
+  in_progress.push(copy);
+
 }
 
 void
 TypeReconstructor::_walk_ARRAY_TYPE_post(const_tree t)
 {
+  const_tree t2 = for_reference.top();
+  gcc_assert(t2 == t);
+  for_reference.pop();
+  tree copy = in_progress.top();
+  in_progress.pop();
+
+  bool is_modified = get_is_modified(t);
+
+  copy = is_modified ? build_distinct_type_copy(copy) : copy;
+  log("array is modified ? %s\n", is_modified ? "t" : "f");
+  TREE_TYPE(copy) = is_modified ? _reorg_map[TREE_TYPE(t)] : TREE_TYPE(copy);
+  TYPE_NAME(copy) = is_modified ? get_new_identifier(copy) : TYPE_NAME(copy);
+  // This is useful so that we go again through type layout
+  TYPE_SIZE(copy) = is_modified ? NULL : TYPE_SIZE(copy);
+  if (is_modified) layout_type(copy);
+
+  _reorg_map[t] = is_modified ? copy : (tree)t;
 }
 
 void
 TypeReconstructor::_walk_POINTER_TYPE_pre(const_tree t)
 {
+  for_reference.push(t);
+  set_is_not_modified_yet(t);
+
+  tree copy = build_variant_type_copy((tree) t);
+  in_progress.push(copy);
 }
 
 void
 TypeReconstructor::_walk_POINTER_TYPE_post(const_tree t)
 {
+  const_tree t2 = for_reference.top();
+  gcc_assert(t2 == t);
+  for_reference.pop();
+  tree copy = in_progress.top();
+  in_progress.pop();
+
+  bool is_modified = get_is_modified(t);
+
+  copy = is_modified ? build_distinct_type_copy(copy) : copy;
+  TYPE_NAME(copy) = is_modified ? get_new_identifier(copy) : TYPE_NAME(copy);
+  // This is useful so that we go again through type layout
+  TYPE_SIZE(copy) = is_modified ? NULL : TYPE_SIZE(copy);
+  if (is_modified) layout_type(copy);
+  
+  _reorg_map[t] = is_modified ? copy : (tree)t;
 }
 
 void
 TypeReconstructor::_walk_RECORD_TYPE_pre(const_tree t)
 {
+  set_is_not_modified_yet(t);
   for_reference.push(t);
   // We don't know if we will modify this type t
   // So, let's make a copy. Just in case.
-  tree copy = build_distinct_type_copy((tree) t);
+  tree copy = build_variant_type_copy((tree) t);
   in_progress.push(copy);
   field_list_stack.push( field_tuple_list_t() );
 }
@@ -140,13 +228,30 @@ TypeReconstructor::_walk_RECORD_TYPE_post(const_tree t)
   }
 
 
+  bool is_modified = get_is_modified(t);
   // Ok, so now that we have fixed the TYPE_FIELDS of the copy...
   // We need to call layout_type
-  TYPE_NAME(copy) = get_new_identifier(copy);
+  copy = is_modified ? build_distinct_type_copy(copy) : copy;
+  TYPE_NAME(copy) = is_modified ? get_new_identifier(copy) : TYPE_NAME(copy);
   // This is useful so that we go again through type layout
-  TYPE_SIZE(copy) = NULL;
-  layout_type(copy);
-  _reorg_map[t] = copy;
+  TYPE_SIZE(copy) = is_modified ? NULL : TYPE_SIZE(copy);
+  if (is_modified) layout_type(copy);
+  _reorg_map[t] = is_modified ? copy : (tree)t;
+
+  /*
+  if (for_reference.empty()) return;
+  gcc_assert(!in_progress.empty());
+
+  // Now we need to find out
+  // if we are modifying something in the parent as well?
+  const_tree possible_field = for_reference.top();
+  const enum tree_code code = TREE_CODE(possible_field);
+  const bool is_field = FIELD_DECL == code;
+  if (!is_field) return;
+
+  tree field_in_progress = in_progress.top();
+  TREE_TYPE(field_in_progress) = copy;
+  */
 }
 
 void
@@ -167,7 +272,7 @@ TypeReconstructor::_walk_field_pre(const_tree t)
   // that we are working on. So proactively, let's make
   // a copy
   tree copy = copy_node((tree) t);
-  tree type_copy = build_distinct_type_copy((tree)(TREE_TYPE(t)));
+  tree type_copy = build_variant_type_copy((tree)(TREE_TYPE(t)));
   TREE_TYPE(copy) = type_copy;
   // To communicate this field to the other methods,
   // let's put it in the "in_progress" stack.
@@ -201,10 +306,15 @@ TypeReconstructor::_walk_field_post(const_tree t)
   unsigned f_bit_offset = tree_to_uhwi(DECL_FIELD_BIT_OFFSET(t));
   unsigned f_offset = 8 * f_byte_offset + f_bit_offset;
 
+
   const bool can_field_be_deleted = field_offsets.find(f_offset) != field_offsets.end();
-  field_tuple_t tuple = std::make_pair(t, can_field_be_deleted ? NULL : copy);
+  if (can_field_be_deleted) mark_all_pointing_here_as_modified();
+  const_tree original_type = TREE_TYPE(t);
+  const bool type_memoized = is_memoized(original_type);
+  // here we did a modification
 
-  log("can field %s be deleted ? %s\n", TypeStringifier::get_field_identifier(t).c_str(), can_field_be_deleted ? "t" : "f");
+  TREE_TYPE(copy) = type_memoized ? _reorg_map[TREE_TYPE(t)] : TREE_TYPE(copy);
+  field_tuple_t tuple = std::make_pair(t, can_field_be_deleted ? NULL : copy);
 
   // Put the field into the vector
   field_tuple_list_t &field_tuple_list = field_list_stack.top();
diff --git a/gcc/type-reconstructor.hpp b/gcc/type-reconstructor.hpp
index 79e6fad8a73..e70776a073b 100644
--- a/gcc/type-reconstructor.hpp
+++ b/gcc/type-reconstructor.hpp
@@ -12,6 +12,7 @@ class TypeReconstructor : public TypeWalker
 public:
   typedef std::map<const_tree, tree> reorg_record_map_t;
   typedef std::map<const_tree, tree> reorg_field_map_t;
+  typedef std::map<const_tree, bool> is_modified_map_t;
   typedef std::set<unsigned> field_offsets_t;
   typedef std::map<const_tree, field_offsets_t> record_field_offset_map_t;
 private:
@@ -24,6 +25,10 @@ private:
   field_tuple_list_stack_t field_list_stack;
   reorg_record_map_t _reorg_map;
   reorg_field_map_t _reorg_fields;
+  is_modified_map_t modified_map;
+  void set_is_not_modified_yet(const_tree);
+  void mark_all_pointing_here_as_modified();
+  bool get_is_modified(const_tree);
   virtual void _walk_field_pre(const_tree);
   virtual void _walk_field_post(const_tree);
   virtual void _walk_RECORD_TYPE_pre(const_tree);