[patch] Fix PR middle-end/68251

[Eric Botcazou <ebotcazou at adacore dot com>]

Hi,

I don't understand how this didn't show up sooner given the amount of testing, 
but there is a nasty overloading for the new REF_REVERSE_STORAGE_ORDER flag:

#define REF_REVERSE_STORAGE_ORDER(NODE) \
   (TREE_CHECK2 (NODE, BIT_FIELD_REF, MEM_REF)->base.u.bits.saturating_flag)

saturating_flag is part of the 'bits' structure, which is itself part of the 
'u' union, which also contains the dependence_info structure, and:

#define MR_DEPENDENCE_CLIQUE(NODE) \
  (TREE_CHECK2 (NODE, MEM_REF, TARGET_MEM_REF)->base.u.dependence_info.clique)
#define MR_DEPENDENCE_BASE(NODE) \
  (TREE_CHECK2 (NODE, MEM_REF, TARGET_MEM_REF)->base.u.dependence_info.base)

So there is a conflict on MEM_REF nodes.  Therefore the attached patch changes 
REF_REVERSE_STORAGE_ORDER to use the default_def_flag instead.

Tested on x86_64-suse-linux, OK for the mainline?  I'll install the Fortran 
testcase once it is reduced because it takes a while to compile ATM.


2015-11-09  Eric Botcazou  <ebotcazou@adacore.com>

        PR middle-end/68251
	* tree-core.h (REF_REVERSE_STORAGE_ORDER): Move around.
	* tree.h (REF_REVERSE_STORAGE_ORDER): Change to default_def_flag.
	* tree-streamer-in.c (unpack_ts_base_value_fields): Adjust.
	* tree-streamer-out.c (pack_ts_base_value_fields): Likewise.

-- 
Eric Botcazou

Index: tree-core.h
===================================================================
--- tree-core.h	(revision 229993)
+++ tree-core.h	(working copy)
@@ -1157,9 +1157,6 @@ struct GTY(()) tree_base {
        TYPE_SATURATING in
            other types
 
-       REF_REVERSE_STORAGE_ORDER in
-           BIT_FIELD_REF, MEM_REF
-
        VAR_DECL_IS_VIRTUAL_OPERAND in
 	   VAR_DECL
 
@@ -1174,6 +1171,9 @@ struct GTY(()) tree_base {
 
    default_def_flag:
 
+       TYPE_FINAL_P in
+	   RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
+
        TYPE_VECTOR_OPAQUE in
 	   VECTOR_TYPE
 
@@ -1183,8 +1183,8 @@ struct GTY(()) tree_base {
        DECL_NONLOCAL_FRAME in
 	   VAR_DECL
 
-       TYPE_FINAL_P in
-	   RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
+       REF_REVERSE_STORAGE_ORDER in
+           BIT_FIELD_REF, MEM_REF
 */
 
 struct GTY(()) tree_typed {
Index: tree.h
===================================================================
--- tree.h	(revision 229993)
+++ tree.h	(working copy)
@@ -927,7 +927,7 @@ extern void omp_clause_range_check_faile
    But, of course, the storage order must be preserved when the accesses
    themselves are rewritten or transformed.  */
 #define REF_REVERSE_STORAGE_ORDER(NODE) \
-  (TREE_CHECK2 (NODE, BIT_FIELD_REF, MEM_REF)->base.u.bits.saturating_flag)
+  (TREE_CHECK2 (NODE, BIT_FIELD_REF, MEM_REF)->base.default_def_flag)
 
 /* These flags are available for each language front end to use internally.  */
 #define TREE_LANG_FLAG_0(NODE) \
Index: tree-streamer-in.c
===================================================================
--- tree-streamer-in.c	(revision 229993)
+++ tree-streamer-in.c	(working copy)
@@ -143,7 +143,10 @@ unpack_ts_base_value_fields (struct bitp
       TYPE_ADDR_SPACE (expr) = (unsigned) bp_unpack_value (bp, 8);
     }
   else if (TREE_CODE (expr) == BIT_FIELD_REF || TREE_CODE (expr) == MEM_REF)
-    REF_REVERSE_STORAGE_ORDER (expr) = (unsigned) bp_unpack_value (bp, 1);
+    {
+      REF_REVERSE_STORAGE_ORDER (expr) = (unsigned) bp_unpack_value (bp, 1);
+      bp_unpack_value (bp, 8);
+    }
   else if (TREE_CODE (expr) == SSA_NAME)
     {
       SSA_NAME_IS_DEFAULT_DEF (expr) = (unsigned) bp_unpack_value (bp, 1);
Index: tree-streamer-out.c
===================================================================
--- tree-streamer-out.c	(revision 229993)
+++ tree-streamer-out.c	(working copy)
@@ -117,7 +117,10 @@ pack_ts_base_value_fields (struct bitpac
       bp_pack_value (bp, TYPE_ADDR_SPACE (expr), 8);
     }
   else if (TREE_CODE (expr) == BIT_FIELD_REF || TREE_CODE (expr) == MEM_REF)
-    bp_pack_value (bp, REF_REVERSE_STORAGE_ORDER (expr), 1);
+    {
+      bp_pack_value (bp, REF_REVERSE_STORAGE_ORDER (expr), 1);
+      bp_pack_value (bp, 0, 8);
+    }
   else if (TREE_CODE (expr) == SSA_NAME)
     {
       bp_pack_value (bp, SSA_NAME_IS_DEFAULT_DEF (expr), 1);