Move copy_phi_arg_into_existing_phi to common location and use it

While improving replace_phi_edge_with_variable for the diamond formed bb
case, I need a way to copy phi entries from one edge to another as I am
removing a forwarding bb inbetween. I was pointed out that jump threading
code had copy_phi_arg_into_existing_phi which I can use.
I also noticed that both gimple_duplicate_sese_tail and
remove_forwarder_block have similar code so it makes sense to use that function
in those two locations too.

OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	* tree-ssa-threadupdate.cc (copy_phi_arg_into_existing_phi): Move to ...
	* tree-cfg.cc (copy_phi_arg_into_existing_phi): Here and remove static.
	(gimple_duplicate_sese_tail): Use copy_phi_arg_into_existing_phi instead
	of an inline version of it.
	* tree-cfgcleanup.cc (remove_forwarder_block): Likewise.
	* tree-cfg.h (copy_phi_arg_into_existing_phi): New declaration.

diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index 21cf6fca25917f874d501d2cbfb731b3aa166150..0aeebb67fac864db284985f4a6f0653af281d62b 100644 (file)
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -6802,6 +6802,32 @@ bb_part_of_region_p (basic_block bb, basic_block* bbs, unsigned n_region)
   return false;
 }
 
+
+/* For each PHI in BB, copy the argument associated with SRC_E to TGT_E.
+   Assuming the argument exists, just does not have a value.  */
+
+void
+copy_phi_arg_into_existing_phi (edge src_e, edge tgt_e)
+{
+  int src_idx = src_e->dest_idx;
+  int tgt_idx = tgt_e->dest_idx;
+
+  /* Iterate over each PHI in e->dest.  */
+  for (gphi_iterator gsi = gsi_start_phis (src_e->dest),
+                          gsi2 = gsi_start_phis (tgt_e->dest);
+       !gsi_end_p (gsi);
+       gsi_next (&gsi), gsi_next (&gsi2))
+    {
+      gphi *src_phi = gsi.phi ();
+      gphi *dest_phi = gsi2.phi ();
+      tree val = gimple_phi_arg_def (src_phi, src_idx);
+      location_t locus = gimple_phi_arg_location (src_phi, src_idx);
+
+      SET_PHI_ARG_DEF (dest_phi, tgt_idx, val);
+      gimple_phi_arg_set_location (dest_phi, tgt_idx, locus);
+    }
+}
+
 /* Duplicates REGION consisting of N_REGION blocks.  The new blocks
    are stored to REGION_COPY in the same order in that they appear
    in REGION, if REGION_COPY is not NULL.  ENTRY is the entry to
@@ -6847,9 +6873,6 @@ gimple_duplicate_sese_tail (edge entry, edge exit,
   gimple_stmt_iterator gsi;
   edge sorig, snew;
   basic_block exit_bb;
-  gphi_iterator psi;
-  gphi *phi;
-  tree def;
   class loop *target, *aloop, *cloop;
 
   gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
@@ -6947,14 +6970,7 @@ gimple_duplicate_sese_tail (edge entry, edge exit,
        gcc_assert (single_succ_edge (region_copy[i]));
        e = redirect_edge_and_branch (single_succ_edge (region_copy[i]), exit_bb);
        PENDING_STMT (e) = NULL;
-       for (psi = gsi_start_phis (exit_bb);
-            !gsi_end_p (psi);
-            gsi_next (&psi))
-         {
-           phi = psi.phi ();
-           def = PHI_ARG_DEF (phi, nexits[0]->dest_idx);
-           add_phi_arg (phi, def, e, gimple_phi_arg_location_from_edge (phi, e));
-         }
+       copy_phi_arg_into_existing_phi (nexits[0], e);
       }
   e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
   PENDING_STMT (e) = NULL;

diff --git a/gcc/tree-cfg.h b/gcc/tree-cfg.h
index f5f0ea0449a36986e259676d0de3caff516be5d2..57865c58c90d96142b4d691ea50c5c2b34260899 100644 (file)
--- a/gcc/tree-cfg.h
+++ b/gcc/tree-cfg.h
@@ -113,6 +113,7 @@ extern basic_block gimple_switch_default_bb (function *, gswitch *);
 extern edge gimple_switch_edge (function *, gswitch *, unsigned);
 extern edge gimple_switch_default_edge (function *, gswitch *);
 extern bool cond_only_block_p (basic_block);
+extern void copy_phi_arg_into_existing_phi (edge, edge);
 
 /* Return true if the LHS of a call should be removed.  */
 

diff --git a/gcc/tree-cfgcleanup.cc b/gcc/tree-cfgcleanup.cc
index 42b253121220251c630fb27a564af51ed59698fb..193d87e327803bcfd88207c9a3065435428232ee 100644 (file)
--- a/gcc/tree-cfgcleanup.cc
+++ b/gcc/tree-cfgcleanup.cc
@@ -610,17 +610,9 @@ remove_forwarder_block (basic_block bb)
 
       if (s == e)
        {
-         /* Create arguments for the phi nodes, since the edge was not
+         /* Copy arguments for the phi nodes, since the edge was not
             here before.  */
-         for (gphi_iterator psi = gsi_start_phis (dest);
-              !gsi_end_p (psi);
-              gsi_next (&psi))
-           {
-             gphi *phi = psi.phi ();
-             location_t l = gimple_phi_arg_location_from_edge (phi, succ);
-             tree def = gimple_phi_arg_def (phi, succ->dest_idx);
-             add_phi_arg (phi, unshare_expr (def), s, l);
-           }
+         copy_phi_arg_into_existing_phi (succ, s);
        }
     }
 

diff --git a/gcc/tree-ssa-threadupdate.cc b/gcc/tree-ssa-threadupdate.cc
index 33a9106363842572bd3363823be7f7a6a6b22e10..d5416b21a78387c2b9f27c95cb170c6b22efbde6 100644 (file)
--- a/gcc/tree-ssa-threadupdate.cc
+++ b/gcc/tree-ssa-threadupdate.cc
@@ -511,31 +511,6 @@ fwd_jt_path_registry::lookup_redirection_data (edge e, insert_option insert)
     }
 }
 
-/* Similar to copy_phi_args, except that the PHI arg exists, it just
-   does not have a value associated with it.  */
-
-static void
-copy_phi_arg_into_existing_phi (edge src_e, edge tgt_e)
-{
-  int src_idx = src_e->dest_idx;
-  int tgt_idx = tgt_e->dest_idx;
-
-  /* Iterate over each PHI in e->dest.  */
-  for (gphi_iterator gsi = gsi_start_phis (src_e->dest),
-                          gsi2 = gsi_start_phis (tgt_e->dest);
-       !gsi_end_p (gsi);
-       gsi_next (&gsi), gsi_next (&gsi2))
-    {
-      gphi *src_phi = gsi.phi ();
-      gphi *dest_phi = gsi2.phi ();
-      tree val = gimple_phi_arg_def (src_phi, src_idx);
-      location_t locus = gimple_phi_arg_location (src_phi, src_idx);
-
-      SET_PHI_ARG_DEF (dest_phi, tgt_idx, val);
-      gimple_phi_arg_set_location (dest_phi, tgt_idx, locus);
-    }
-}
-
 /* Given ssa_name DEF, backtrack jump threading PATH from node IDX
    to see if it has constant value in a flow sensitive manner.  Set
    LOCUS to location of the constant phi arg and return the value.