Introduce vNULL to use as a nil initializer for vec<>.

This patch implements Jakub's idea of adding an empty struct with
a typecast operator that returns nil vectors.  This is useful to
shorten all the initializers when declaring vec instances or passing
nil vectors as function arguments.

2012-11-20  Diego Novillo  <dnovillo@google.com>
	    Jakub Jelinek  <jakub@redhat.com>

ChangeLog
	* vec.h (struct vnull): Declare.
	(vNULL): Declare.
	* vec.c (vNULL): Define.
	* bb-reorder.c: Replace all vec<T, A>() initializers with vNULL.
	* cfgexpand.c: Likewise.
	* cfgloop.c: Likewise.
	* cfgloopanal.c: Likewise.
	* cfgloopmanip.c: Likewise.
	* cgraph.c: Likewise.
	* config/c6x/c6x.c: Likewise.
	* config/i386/i386.c: Likewise.
	* df-core.c: Likewise.
	* dominance.c: Likewise.
	* dwarf2out.c: Likewise.
	* except.c: Likewise.
	* function.c: Likewise.
	* gcse.c: Likewise.
	* genautomata.c: Likewise.
	* graphds.c: Likewise.
	* graphite-scop-detection.c: Likewise.
	* graphite.c: Likewise.
	* haifa-sched.c: Likewise.
	* ifcvt.c: Likewise.
	* ipa-cp.c: Likewise.
	* ipa-inline-analysis.c: Likewise.
	* ipa-inline-transform.c: Likewise.
	* ipa-inline.c: Likewise.
	* ipa-prop.c: Likewise.
	* ipa-split.c: Likewise.
	* ipa-utils.c: Likewise.
	* ira-build.c: Likewise.
	* lto-cgraph.c: Likewise.
	* lto-streamer-in.c: Likewise.
	* lto-symtab.c: Likewise.
	* opts-global.c: Likewise.
	* passes.c: Likewise.
	* ree.c: Likewise.
	* sched-deps.c: Likewise.
	* sel-sched-ir.c: Likewise.
	* sel-sched-ir.h: Likewise.
	* sel-sched.c: Likewise.
	* stor-layout.c: Likewise.
	* trans-mem.c: Likewise.
	* tree-call-cdce.c: Likewise.
	* tree-cfg.c: Likewise.
	* tree-data-ref.c: Likewise.
	* tree-diagnostic.c: Likewise.
	* tree-eh.c: Likewise.
	* tree-loop-distribution.c: Likewise.
	* tree-predcom.c: Likewise.
	* tree-ssa-loop-im.c: Likewise.
	* tree-ssa-loop-ivcanon.c: Likewise.
	* tree-ssa-loop-manip.c: Likewise.
	* tree-ssa-loop-niter.c: Likewise.
	* tree-ssa-loop-prefetch.c: Likewise.
	* tree-ssa-math-opts.c: Likewise.
	* tree-ssa-phiopt.c: Likewise.
	* tree-ssa-pre.c: Likewise.
	* tree-ssa-propagate.c: Likewise.
	* tree-ssa-reassoc.c: Likewise.
	* tree-ssa-sccvn.c: Likewise.
	* tree-ssa-structalias.c: Likewise.
	* tree-ssa-threadedge.c: Likewise.
	* tree-ssa-uninit.c: Likewise.
	* tree-stdarg.c: Likewise.
	* tree-switch-conversion.c: Likewise.
	* tree-vect-data-refs.c: Likewise.
	* tree-vect-loop.c: Likewise.
	* tree-vect-slp.c: Likewise.
	* tree-vect-stmts.c: Likewise.
	* value-prof.c: Likewise.
	* varasm.c: Likewise.

ada/ChangeLog
	* gcc-interface/decl.c: Replace all vec<T,A>()
	initializers with vNULL.

cp/ChangeLog
	* name-lookup.c: Replace all vec<T, A>() initializers
	with vNULL.
	* semantics.c: Likewise.

fortran/ChangeLog
	* trans-openmp.c: Replace all vec<T, A>() initializers
	with vNULL.

lto/ChangeLog
	* lto.c: Replace all vec<T, A>() initializers with vNULL.

objc/ChangeLog
	* objc-act.c: Replace all vec<T, A>() initializers with vNULL.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@193677 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 7 insertions, 9 deletions

diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index a0f5f5f085c..c22f63bf652 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -1575,7 +1575,7 @@ devirtualization_time_bonus (struct cgraph_node *node,
       tree target;
 
       target = ipa_get_indirect_edge_target (ie, known_csts, known_binfos,
-					vec<ipa_agg_jump_function_p>());
+					vNULL);
       if (!target)
 	continue;
 
@@ -2248,9 +2248,7 @@ ipcp_discover_new_direct_edges (struct cgraph_node *node,
       tree target;
 
       next_ie = ie->next_callee;
-      target = ipa_get_indirect_edge_target (ie, known_vals,
-					vec<tree>(),
-					vec<ipa_agg_jump_function_p>());
+      target = ipa_get_indirect_edge_target (ie, known_vals, vNULL, vNULL);
       if (target)
 	{
 	  ipa_make_edge_direct_to_target (ie, target);
@@ -2731,10 +2729,10 @@ find_more_scalar_values_for_callers_subset (struct cgraph_node *node,
 static vec<ipa_agg_jf_item_t>
 copy_plats_to_inter (struct ipcp_param_lattices *plats, HOST_WIDE_INT offset)
 {
-  vec<ipa_agg_jf_item_t> res = vec<ipa_agg_jf_item_t>();
+  vec<ipa_agg_jf_item_t> res = vNULL;
 
   if (!plats->aggs || plats->aggs_contain_variable || plats->aggs_bottom)
-    return vec<ipa_agg_jf_item>();
+    return vNULL;
 
   for (struct ipcp_agg_lattice *aglat = plats->aggs; aglat; aglat = aglat->next)
     if (ipa_lat_is_single_const (aglat))
@@ -2796,7 +2794,7 @@ static vec<ipa_agg_jf_item_t>
 agg_replacements_to_vector (struct cgraph_node *node, HOST_WIDE_INT offset)
 {
   struct ipa_agg_replacement_value *av;
-  vec<ipa_agg_jf_item_t> res = vec<ipa_agg_jf_item_t>();
+  vec<ipa_agg_jf_item_t> res = vNULL;
 
   for (av = ipa_get_agg_replacements_for_node (node); av; av = av->next)
     {
@@ -2874,7 +2872,7 @@ find_aggregate_values_for_callers_subset (struct cgraph_node *node,
   for (i = 0; i < count ; i++)
     {
       struct cgraph_edge *cs;
-      vec<ipa_agg_jf_item_t> inter = vec<ipa_agg_jf_item_t>();
+      vec<ipa_agg_jf_item_t> inter = vNULL;
       struct ipa_agg_jf_item *item;
       int j;
 
@@ -3283,7 +3281,7 @@ decide_whether_version_node (struct cgraph_node *node)
   struct ipa_node_params *info = IPA_NODE_REF (node);
   int i, count = ipa_get_param_count (info);
   vec<tree> known_csts, known_binfos;
-  vec<ipa_agg_jump_function_t> known_aggs = vec<ipa_agg_jump_function_t>();
+  vec<ipa_agg_jump_function_t> known_aggs = vNULL;
   bool ret = false;
 
   if (count == 0)