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.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r193677

1 files changed, 21 insertions, 21 deletions

diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c
index cfe1275..1e8d7ee 100644
--- a/gcc/tree-vect-stmts.c
+++ b/gcc/tree-vect-stmts.c
@@ -1722,7 +1722,7 @@ vectorizable_call (gimple stmt, gimple_stmt_iterator *gsi, gimple *vec_stmt,
     = {vect_unknown_def_type, vect_unknown_def_type, vect_unknown_def_type};
   gimple new_stmt = NULL;
   int ncopies, j;
-  vec<tree> vargs = vec<tree>();
+  vec<tree> vargs = vNULL;
   enum { NARROW, NONE, WIDEN } modifier;
   size_t i, nargs;
   tree lhs;
@@ -2239,7 +2239,7 @@ vect_create_vectorized_promotion_stmts (vec<tree> *vec_oprnds0,
   int i;
   tree vop0, vop1, new_tmp1, new_tmp2;
   gimple new_stmt1, new_stmt2;
-  vec<tree> vec_tmp = vec<tree>();
+  vec<tree> vec_tmp = vNULL;
 
   vec_tmp.create (vec_oprnds0->length () * 2);
   FOR_EACH_VEC_ELT (*vec_oprnds0, i, vop0)
@@ -2305,13 +2305,13 @@ vectorizable_conversion (gimple stmt, gimple_stmt_iterator *gsi,
   int ncopies, i, j;
   tree lhs_type, rhs_type;
   enum { NARROW, NONE, WIDEN } modifier;
-  vec<tree> vec_oprnds0 = vec<tree>();
-  vec<tree> vec_oprnds1 = vec<tree>();
+  vec<tree> vec_oprnds0 = vNULL;
+  vec<tree> vec_oprnds1 = vNULL;
   tree vop0;
   bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_info);
   int multi_step_cvt = 0;
-  vec<tree> vec_dsts = vec<tree>();
-  vec<tree> interm_types = vec<tree>();
+  vec<tree> vec_dsts = vNULL;
+  vec<tree> interm_types = vNULL;
   tree last_oprnd, intermediate_type, cvt_type = NULL_TREE;
   int op_type;
   enum machine_mode rhs_mode;
@@ -2878,7 +2878,7 @@ vectorizable_assignment (gimple stmt, gimple_stmt_iterator *gsi,
   unsigned int nunits = TYPE_VECTOR_SUBPARTS (vectype);
   int ncopies;
   int i, j;
-  vec<tree> vec_oprnds = vec<tree>();
+  vec<tree> vec_oprnds = vNULL;
   tree vop;
   bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_info);
   gimple new_stmt = NULL;
@@ -3087,8 +3087,8 @@ vectorizable_shift (gimple stmt, gimple_stmt_iterator *gsi,
   tree op1_vectype;
   int ncopies;
   int j, i;
-  vec<tree> vec_oprnds0 = vec<tree>();
-  vec<tree> vec_oprnds1 = vec<tree>();
+  vec<tree> vec_oprnds0 = vNULL;
+  vec<tree> vec_oprnds1 = vNULL;
   tree vop0, vop1;
   unsigned int k;
   bool scalar_shift_arg = true;
@@ -3465,9 +3465,9 @@ vectorizable_operation (gimple stmt, gimple_stmt_iterator *gsi,
   tree vectype_out;
   int ncopies;
   int j, i;
-  vec<tree> vec_oprnds0 = vec<tree>();
-  vec<tree> vec_oprnds1 = vec<tree>();
-  vec<tree> vec_oprnds2 = vec<tree>();
+  vec<tree> vec_oprnds0 = vNULL;
+  vec<tree> vec_oprnds1 = vNULL;
+  vec<tree> vec_oprnds2 = vNULL;
   tree vop0, vop1, vop2;
   bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_info);
   int vf;
@@ -3820,11 +3820,11 @@ vectorizable_store (gimple stmt, gimple_stmt_iterator *gsi, gimple *vec_stmt,
   bool grouped_store = false;
   bool store_lanes_p = false;
   unsigned int group_size, i;
-  vec<tree> dr_chain = vec<tree>();
-  vec<tree> oprnds = vec<tree>();
-  vec<tree> result_chain = vec<tree>();
+  vec<tree> dr_chain = vNULL;
+  vec<tree> oprnds = vNULL;
+  vec<tree> result_chain = vNULL;
   bool inv_p;
-  vec<tree> vec_oprnds = vec<tree>();
+  vec<tree> vec_oprnds = vNULL;
   bool slp = (slp_node != NULL);
   unsigned int vec_num;
   bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_info);
@@ -4337,7 +4337,7 @@ vectorizable_load (gimple stmt, gimple_stmt_iterator *gsi, gimple *vec_stmt,
   tree offset = NULL_TREE;
   tree realignment_token = NULL_TREE;
   gimple phi = NULL;
-  vec<tree> dr_chain = vec<tree>();
+  vec<tree> dr_chain = vNULL;
   bool grouped_load = false;
   bool load_lanes_p = false;
   gimple first_stmt;
@@ -5290,10 +5290,10 @@ vectorizable_condition (gimple stmt, gimple_stmt_iterator *gsi,
   stmt_vec_info prev_stmt_info = NULL;
   int i, j;
   bb_vec_info bb_vinfo = STMT_VINFO_BB_VINFO (stmt_info);
-  vec<tree> vec_oprnds0 = vec<tree>();
-  vec<tree> vec_oprnds1 = vec<tree>();
-  vec<tree> vec_oprnds2 = vec<tree>();
-  vec<tree> vec_oprnds3 = vec<tree>();
+  vec<tree> vec_oprnds0 = vNULL;
+  vec<tree> vec_oprnds1 = vNULL;
+  vec<tree> vec_oprnds2 = vNULL;
+  vec<tree> vec_oprnds3 = vNULL;
   tree vec_cmp_type = vectype;
 
   if (slp_node || PURE_SLP_STMT (stmt_info))