make FOR_EACH_IMM_USE_STMT safe for early exits

Use a dtor to automatically remove ITER from IMM_USE list in
FOR_EACH_IMM_USE_STMT.

for  gcc/ChangeLog

	* ssa-iterators.h (end_imm_use_stmt_traverse): Forward
	declare.
	(auto_end_imm_use_stmt_traverse): New struct.
	(FOR_EACH_IMM_USE_STMT): Use it.
	(BREAK_FROM_IMM_USE_STMT, RETURN_FROM_IMM_USE_STMT): Remove,
	along with uses...
	* gimple-ssa-strength-reduction.c: ... here, ...
	* graphite-scop-detection.c: ... here, ...
	* ipa-modref.c, ipa-pure-const.c, ipa-sra.c: ... here, ...
	* tree-predcom.c, tree-ssa-ccp.c: ... here, ...
	* tree-ssa-dce.c, tree-ssa-dse.c: ... here, ...
	* tree-ssa-loop-ivopts.c, tree-ssa-math-opts.c: ... here, ...
	* tree-ssa-phiprop.c, tree-ssa.c: ... here, ...
	* tree-vect-slp.c: ... and here, ...
	* doc/tree-ssa.texi: ... and the example here.

diff --git a/gcc/doc/tree-ssa.texi b/gcc/doc/tree-ssa.texi
index f927f89cb7f64d693719a4ab6670dd9f3385cb6c..057135f80d11646f046f6a369009f7f8e8666069 100644 (file)
--- a/gcc/doc/tree-ssa.texi
+++ b/gcc/doc/tree-ssa.texi
@@ -385,20 +385,8 @@ optimization can manipulate the stmt when all the uses have been
 processed.  This is a little slower than the FAST version since it adds a
 placeholder element and must sort through the list a bit for each statement.
 This placeholder element must be also be removed if the loop is
-terminated early.  The macro @code{BREAK_FROM_IMM_USE_STMT} is provided
-to do this :
-
-@smallexample
-  FOR_EACH_IMM_USE_STMT (stmt, iterator, ssa_var)
-    @{
-      if (stmt == last_stmt)
-        BREAK_FROM_IMM_USE_STMT (iterator);
-
-      FOR_EACH_IMM_USE_ON_STMT (imm_use_p, iterator)
-        SET_USE (imm_use_p, ssa_var_2);
-      fold_stmt (stmt);
-    @}
-@end smallexample
+terminated early; a destructor takes care of that when leaving the
+@code{FOR_EACH_IMM_USE_STMT} scope.
 
 There are checks in @code{verify_ssa} which verify that the immediate use list
 is up to date, as well as checking that an optimization didn't break from the

diff --git a/gcc/gimple-ssa-strength-reduction.c b/gcc/gimple-ssa-strength-reduction.c
index b6cbb21dfbc73f44f7258dee912a9cf8d5d85c98..a92cf03c1f322733dda978dc5c31105cdda996e4 100644 (file)
--- a/gcc/gimple-ssa-strength-reduction.c
+++ b/gcc/gimple-ssa-strength-reduction.c
@@ -524,7 +524,7 @@ uses_consumed_by_stmt (tree name, gimple *stmt, unsigned recurse = 0)
                                     recurse + 1))
        {
          retval = false;
-         BREAK_FROM_IMM_USE_STMT (iter);
+         break;
        }
     }
 

diff --git a/gcc/graphite-scop-detection.c b/gcc/graphite-scop-detection.c
index 4f7bbe5d03524c009fed8db5d6fd0c40b3b0ac62..3e729b159b095d5471df2afeb520e2cf0811b808 100644 (file)
--- a/gcc/graphite-scop-detection.c
+++ b/gcc/graphite-scop-detection.c
@@ -1262,9 +1262,7 @@ build_cross_bb_scalars_def (scop_p scop, tree def, basic_block def_bb,
        && (def_bb != gimple_bb (use_stmt) && !is_gimple_debug (use_stmt)))
       {
        add_write (writes, def);
-       /* This is required by the FOR_EACH_IMM_USE_STMT when we want to break
-          before all the uses have been visited.  */
-       BREAK_FROM_IMM_USE_STMT (imm_iter);
+       break;
       }
 }
 

diff --git a/gcc/ipa-modref.c b/gcc/ipa-modref.c
index 04613201f1f1ec0e9b580f712f0d689323d1ed1a..74ad876cf581ec211041a2e83c8f0235f9dfcec8 100644 (file)
--- a/gcc/ipa-modref.c
+++ b/gcc/ipa-modref.c
@@ -1597,9 +1597,7 @@ analyze_ssa_name_flags (tree name, vec<modref_lattice> &lattice, int depth,
   FOR_EACH_IMM_USE_STMT (use_stmt, ui, name)
     {
       if (lattice[index].flags == 0)
-       {
-         BREAK_FROM_IMM_USE_STMT (ui);
-       }
+       break;
       if (is_gimple_debug (use_stmt))
        continue;
       if (dump_file)

diff --git a/gcc/ipa-pure-const.c b/gcc/ipa-pure-const.c
index 66f217711078828bf3a98a1b8852b6a23c9c9a0b..957217ae4ae344c7dc9958d546d98804ed96a420 100644 (file)
--- a/gcc/ipa-pure-const.c
+++ b/gcc/ipa-pure-const.c
@@ -842,20 +842,20 @@ check_retval_uses (tree retval, gimple *stmt)
       {
        tree op2 = gimple_cond_rhs (cond);
        if (!integer_zerop (op2))
-         RETURN_FROM_IMM_USE_STMT (use_iter, false);
+         return false;
       }
     else if (gassign *ga = dyn_cast<gassign *> (use_stmt))
       {
        enum tree_code code = gimple_assign_rhs_code (ga);
        if (TREE_CODE_CLASS (code) != tcc_comparison)
-         RETURN_FROM_IMM_USE_STMT (use_iter, false);
+         return false;
        if (!integer_zerop (gimple_assign_rhs2 (ga)))
-         RETURN_FROM_IMM_USE_STMT (use_iter, false);
+         return false;
       }
     else if (is_gimple_debug (use_stmt))
       ;
     else if (use_stmt != stmt)
-      RETURN_FROM_IMM_USE_STMT (use_iter, false);
+      return false;
 
   return true;
 }

diff --git a/gcc/ipa-sra.c b/gcc/ipa-sra.c
index d0579231d9cfc1eb320ac05d82c67beca6f68f59..5d2c0dfce533e956d85b28a6f303a96256f6674f 100644 (file)
--- a/gcc/ipa-sra.c
+++ b/gcc/ipa-sra.c
@@ -850,7 +850,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
              || (arg_count = gimple_call_num_args (call)) == 0)
            {
              res = -1;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
 
          cgraph_edge *cs = node->get_edge (stmt);
@@ -874,7 +874,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
              || all_uses != simple_uses)
            {
              res = -1;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
          res += all_uses;
        }
@@ -891,7 +891,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
          if (TREE_CODE (lhs) != SSA_NAME)
            {
              res = -1;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
          gcc_assert (!gimple_vdef (stmt));
          if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs)))
@@ -901,7 +901,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
              if (tmp < 0)
                {
                  res = tmp;
-                 BREAK_FROM_IMM_USE_STMT (imm_iter);
+                 break;
                }
              res += tmp;
            }
@@ -909,7 +909,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
       else
        {
          res = -1;
-         BREAK_FROM_IMM_USE_STMT (imm_iter);
+         break;
        }
     }
   return res;
@@ -1016,7 +1016,7 @@ ptr_parm_has_nonarg_uses (cgraph_node *node, function *fun, tree parm,
              || (arg_count = gimple_call_num_args (call)) == 0)
            {
              ret = true;
-             BREAK_FROM_IMM_USE_STMT (ui);
+             break;
            }
 
          cgraph_edge *cs = node->get_edge (stmt);
@@ -1062,7 +1062,7 @@ ptr_parm_has_nonarg_uses (cgraph_node *node, function *fun, tree parm,
       if (uses_ok != all_uses)
        {
          ret = true;
-         BREAK_FROM_IMM_USE_STMT (ui);
+         break;
        }
     }
 
@@ -1975,7 +1975,7 @@ ssa_name_only_returned_p (tree name, bitmap analyzed)
          if (t != name)
            {
              res = false;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
        }
       else if ((is_gimple_assign (stmt) && !gimple_has_volatile_ops (stmt))
@@ -1991,20 +1991,20 @@ ssa_name_only_returned_p (tree name, bitmap analyzed)
          if (TREE_CODE (lhs) != SSA_NAME)
            {
              res = false;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
          gcc_assert (!gimple_vdef (stmt));
          if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs))
              && !ssa_name_only_returned_p (lhs, analyzed))
            {
              res = false;
-             BREAK_FROM_IMM_USE_STMT (imm_iter);
+             break;
            }
        }
       else
        {
          res = false;
-         BREAK_FROM_IMM_USE_STMT (imm_iter);
+         break;
        }
     }
   return res;

diff --git a/gcc/ssa-iterators.h b/gcc/ssa-iterators.h
index c0b45b63db442347c211bfbcbc55ef82e27b87b1..f70b0a42368d7e2a0fe8cb94997751b16e37a422 100644 (file)
--- a/gcc/ssa-iterators.h
+++ b/gcc/ssa-iterators.h
@@ -77,29 +77,32 @@ struct imm_use_iterator
        !end_readonly_imm_use_p (&(ITER));                      \
        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 
-/* Use this iterator to visit each stmt which has a use of SSAVAR.  */
+/* Forward declare for use in the class below.  */
+static inline void end_imm_use_stmt_traverse (imm_use_iterator *);
+
+/* arrange to automatically call, upon descruction, end_imm_use_stmt_traverse
+   with a given pointer to imm_use_iterator.  */
+struct auto_end_imm_use_stmt_traverse
+{
+  imm_use_iterator *imm;
+  auto_end_imm_use_stmt_traverse (imm_use_iterator *imm)
+  : imm (imm) {}
+  ~auto_end_imm_use_stmt_traverse ()
+  { end_imm_use_stmt_traverse (imm); }
+};
+
+/* Use this iterator to visit each stmt which has a use of SSAVAR.  The
+   destructor of the auto_end_imm_use_stmt_traverse object deals with removing
+   ITER from SSAVAR's IMM_USE list even when leaving the scope early.  */
 
 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)              \
-  for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));                \
+  for (struct auto_end_imm_use_stmt_traverse                   \
+        auto_end_imm_use_stmt_traverse                         \
+          ((((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR))), \
+            &(ITER)));                                         \
        !end_imm_use_stmt_p (&(ITER));                          \
        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 
-/* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
-   do so will result in leaving a iterator marker node in the immediate
-   use list, and nothing good will come from that.   */
-#define BREAK_FROM_IMM_USE_STMT(ITER)                          \
-   {                                                           \
-     end_imm_use_stmt_traverse (&(ITER));                      \
-     break;                                                    \
-   }
-
-/* Similarly for return.  */
-#define RETURN_FROM_IMM_USE_STMT(ITER, VAL)                    \
-  {                                                            \
-    end_imm_use_stmt_traverse (&(ITER));                       \
-    return (VAL);                                              \
-  }
-
 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
    get access to each occurrence of ssavar on the stmt returned by
    that iterator..  for instance:

diff --git a/gcc/tree-predcom.c b/gcc/tree-predcom.c
index 265c3bbe445b09ad430cf12c8d3c78d167dc78f0..5482f50198a6ed3176dfd263410e03535cca7390 100644 (file)
--- a/gcc/tree-predcom.c
+++ b/gcc/tree-predcom.c
@@ -2367,7 +2367,7 @@ base_names_in_chain_on (class loop *loop, tree name, tree var)
              && flow_bb_inside_loop_p (loop, gimple_bb (stmt)))
            {
              phi = stmt;
-             BREAK_FROM_IMM_USE_STMT (iter);
+             break;
            }
        }
       if (!phi)

diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index c5c2e2a61075c18b040b3beb996b7216fa03cb38..965f092ccccb4a6f7b947b069eea2bfe286b4610 100644 (file)
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -3020,7 +3020,7 @@ optimize_atomic_bit_test_and (gimple_stmt_iterator *gsip,
        }
 
       use_bool = false;
-      BREAK_FROM_IMM_USE_STMT (iter);
+      break;
     }
 
   tree new_lhs = make_ssa_name (TREE_TYPE (lhs));

diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c
index d155bdfb2aefd121a578fc81f609946592ca4933..51d4fcbb1c84ad63d29714eacdbaa16f813ac586 100644 (file)
--- a/gcc/tree-ssa-dce.c
+++ b/gcc/tree-ssa-dce.c
@@ -1516,7 +1516,7 @@ eliminate_unnecessary_stmts (void)
                            || gimple_plf (stmt, STMT_NECESSARY))
                          {
                            found = true;
-                           BREAK_FROM_IMM_USE_STMT (iter);
+                           break;
                          }
                      }
                    if (found)

diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c
index cc252fcc20e5b92649e43280d234b23ad9f5ae04..4967a5a99272ba1c4e7ce4c4d1309b61665a16fd 100644 (file)
--- a/gcc/tree-ssa-dse.c
+++ b/gcc/tree-ssa-dse.c
@@ -693,7 +693,7 @@ dse_optimize_redundant_stores (gimple *stmt)
     {
       /* Limit stmt walking.  */
       if (++cnt > param_dse_max_alias_queries_per_store)
-       BREAK_FROM_IMM_USE_STMT (ui);
+       break;
 
       /* If USE_STMT stores 0 into one or more of the same locations
         as STMT and STMT would kill USE_STMT, then we can just remove
@@ -712,7 +712,7 @@ dse_optimize_redundant_stores (gimple *stmt)
          ao_ref write;
 
          if (!initialize_ao_ref_for_dse (use_stmt, &write))
-           BREAK_FROM_IMM_USE_STMT (ui)
+           break;
 
          if (valid_ao_ref_for_dse (&write)
              && stmt_kills_ref_p (stmt, &write))
@@ -805,7 +805,7 @@ dse_classify_store (ao_ref *ref, gimple *stmt,
          if (++cnt > param_dse_max_alias_queries_per_store)
            {
              fail = true;
-             BREAK_FROM_IMM_USE_STMT (ui);
+             break;
            }
 
          /* We have visited ourselves already so ignore STMT for the
@@ -852,7 +852,7 @@ dse_classify_store (ao_ref *ref, gimple *stmt,
                }
 
              fail = true;
-             BREAK_FROM_IMM_USE_STMT (ui);
+             break;
            }
          /* If this is a store, remember it as we possibly need to walk the
             defs uses.  */

diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c
index 8e66da1e923211269073f8f2d934f573c094f13b..4012ae3f19ddb7ac6e51522ac9db86fd88a7ec04 100644 (file)
--- a/gcc/tree-ssa-loop-ivopts.c
+++ b/gcc/tree-ssa-loop-ivopts.c
@@ -7627,7 +7627,7 @@ remove_unused_ivs (struct ivopts_data *data, bitmap toremove)
                    count++;
 
                  if (count > 1)
-                   BREAK_FROM_IMM_USE_STMT (imm_iter);
+                   break;
                }
 
              if (!count)

diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c
index 74a16b66223d07726a898d9101d7f2af8777c603..91b3d1baa34ef8ec5151c9113fcf0a7a7e78d577 100644 (file)
--- a/gcc/tree-ssa-math-opts.c
+++ b/gcc/tree-ssa-math-opts.c
@@ -1285,7 +1285,7 @@ execute_cse_sincos_1 (tree name)
         and, in subsequent rounds, that the built_in type is the same
         type, or a compatible type.  */
       if (type != t && !types_compatible_p (type, t))
-       RETURN_FROM_IMM_USE_STMT (use_iter, false);
+       return false;
     }
   if (seen_cos + seen_sin + seen_cexpi <= 1)
     return false;

diff --git a/gcc/tree-ssa-phiprop.c b/gcc/tree-ssa-phiprop.c
index d5cbf33bdbcc56756456ba8de1fe1dcfa6a921a8..64d6eda5f6c26a6709b000a77586412f5429f418 100644 (file)
--- a/gcc/tree-ssa-phiprop.c
+++ b/gcc/tree-ssa-phiprop.c
@@ -119,7 +119,7 @@ phivn_valid_p (struct phiprop_d *phivn, tree name, basic_block bb)
          && !dominated_by_p (CDI_DOMINATORS, gimple_bb (use_stmt), bb))
        {
          ok = false;
-         BREAK_FROM_IMM_USE_STMT (ui2);
+         break;
        }
     }
 

diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c
index 2a6d0866e9f8d2f2ba0e107abb25b356d0659d42..cf54c8914268d3d84a98bb287d519ddda3ce0120 100644 (file)
--- a/gcc/tree-ssa.c
+++ b/gcc/tree-ssa.c
@@ -607,7 +607,7 @@ release_defs_bitset (bitmap toremove)
                }
 
              if (!remove_now)
-               BREAK_FROM_IMM_USE_STMT (uit);
+               break;
            }
 
          if (remove_now)

diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c
index e7191ed3267378638e45ddb02b88af0c50ecb116..877d44b2257bb6b4081e15dc4bc776722323d2eb 100644 (file)
--- a/gcc/tree-vect-slp.c
+++ b/gcc/tree-vect-slp.c
@@ -3857,7 +3857,7 @@ vect_bb_slp_mark_live_stmts (bb_vec_info bb_vinfo, slp_tree node,
                      mark_visited = false;
                    else
                      STMT_VINFO_LIVE_P (stmt_info) = false;
-                   BREAK_FROM_IMM_USE_STMT (use_iter);
+                   break;
                  }
              }
          /* We have to verify whether we can insert the lane extract
@@ -4124,7 +4124,7 @@ vect_bb_slp_scalar_cost (vec_info *vinfo,
                              (vect_stmt_to_vectorize (use_stmt_info)))
                      {
                        (*life)[i] = true;
-                       BREAK_FROM_IMM_USE_STMT (use_iter);
+                       break;
                      }
                  }
            }