libgomp: Fix default futex vs errno

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

diff --git a/gcc/tree-ssa-phiprop.c b/gcc/tree-ssa-phiprop.c
index 3064437..7dd94a4 100644 (file)
--- a/gcc/tree-ssa-phiprop.c
+++ b/gcc/tree-ssa-phiprop.c
@@ -314,6 +314,12 @@ propagate_with_phi (basic_block bb, gimple phi, struct phiprop_d *phivn,
       gimple def_stmt;
       tree vuse;
 
+      /* Only replace loads in blocks that post-dominate the PHI node.  That
+         makes sure we don't end up speculating loads.  */
+      if (!dominated_by_p (CDI_POST_DOMINATORS,
+                          bb, gimple_bb (use_stmt)))
+       continue;
+         
       /* Check whether this is a load of *ptr.  */
       if (!(is_gimple_assign (use_stmt)
            && TREE_CODE (gimple_assign_lhs (use_stmt)) == SSA_NAME
@@ -385,6 +391,7 @@ tree_ssa_phiprop (void)
   size_t n;
 
   calculate_dominance_info (CDI_DOMINATORS);
+  calculate_dominance_info (CDI_POST_DOMINATORS);
 
   n = num_ssa_names;
   phivn = XCNEWVEC (struct phiprop_d, n);
@@ -402,6 +409,8 @@ tree_ssa_phiprop (void)
   VEC_free (basic_block, heap, bbs);
   free (phivn);
 
+  free_dominance_info (CDI_POST_DOMINATORS);
+
   return 0;
 }