PR middle-end/44828

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-ter.c

diff --git a/gcc/tree-ssa-ter.c b/gcc/tree-ssa-ter.c
index d9d552c..a997f78 100644 (file)
--- a/gcc/tree-ssa-ter.c
+++ b/gcc/tree-ssa-ter.c
@@ -25,7 +25,6 @@ along with GCC; see the file COPYING3.  If not see
 #include "coretypes.h"
 #include "tm.h"
 #include "tree.h"
-#include "diagnostic.h"
 #include "tree-pretty-print.h"
 #include "gimple-pretty-print.h"
 #include "bitmap.h"
@@ -617,6 +616,24 @@ find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb)
                      }
                  }
 
+             /* If the stmt does a memory store and the replacement
+                is a load aliasing it avoid creating overlapping
+                assignments which we cannot expand correctly.  */
+             if (gimple_vdef (stmt)
+                 && gimple_assign_single_p (stmt))
+               {
+                 gimple def_stmt = SSA_NAME_DEF_STMT (use);
+                 while (is_gimple_assign (def_stmt)
+                        && gimple_assign_rhs_code (def_stmt) == SSA_NAME)
+                   def_stmt
+                     = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (def_stmt));
+                 if (gimple_vuse (def_stmt)
+                     && gimple_assign_single_p (def_stmt)
+                     && refs_may_alias_p (gimple_assign_lhs (stmt),
+                                          gimple_assign_rhs1 (def_stmt)))
+                   same_root_var = true;
+               }
+
              /* Mark expression as replaceable unless stmt is volatile or the
                 def variable has the same root variable as something in the
                 substitution list.  */
@@ -705,7 +722,7 @@ dump_replaceable_exprs (FILE *f, bitmap expr)
    exclusively to debug TER.  F is the place to send debug info and T is the
    table being debugged.  */
 
-void
+DEBUG_FUNCTION void
 debug_ter (FILE *f, temp_expr_table_p t)
 {
   unsigned x, y;