[COMMITTED, PR 50628] More careful SRA sub-access propagation accross assignments

[Martin Jambor]

Hi,

Richi approved the following patch to fix 50628 on IRC.  Details about
the problem and this particular patch are also in bugzilla.  Of
course, I bootstrapped and tested the patch today on x86_64-linux.

Thanks,

Martin


2011-12-13  Martin Jambor  <mjam...@suse.cz>

        PR middle-end/50628
        * tree-sra.c (propagate_subaccesses_across_link): Do not propagate
        sub-accesses of scalar accesses.

Index: src/gcc/tree-sra.c
===================================================================
--- src.orig/gcc/tree-sra.c
+++ src/gcc/tree-sra.c
@@ -2234,21 +2234,23 @@ propagate_subaccesses_across_link (struc
       || racc->grp_unscalarizable_region)
     return false;
 
-  if (!lacc->first_child && !racc->first_child
-      && is_gimple_reg_type (racc->type))
+  if (is_gimple_reg_type (racc->type))
     {
-      tree t = lacc->base;
-
-      lacc->type = racc->type;
-      if (build_user_friendly_ref_for_offset (&t, TREE_TYPE (t), lacc->offset,
-                                             racc->type))
-       lacc->expr = t;
-      else
+      if (!lacc->first_child && !racc->first_child)
        {
-         lacc->expr = build_ref_for_model (EXPR_LOCATION (lacc->base),
-                                           lacc->base, lacc->offset,
-                                           racc, NULL, false);
-         lacc->grp_no_warning = true;
+         tree t = lacc->base;
+
+         lacc->type = racc->type;
+         if (build_user_friendly_ref_for_offset (&t, TREE_TYPE (t),
+                                                 lacc->offset, racc->type))
+           lacc->expr = t;
+         else
+           {
+             lacc->expr = build_ref_for_model (EXPR_LOCATION (lacc->base),
+                                               lacc->base, lacc->offset,
+                                               racc, NULL, false);
+             lacc->grp_no_warning = true;
+           }
        }
       return false;
     }