* doc/tree-ssa.texi: Remove references to VDEF and add descriptions

	of V_MAY_DEF and V_MUST_DEF.
	* tree-dfa.c (dfa_stats_d): Add num_v_must_defs and rename
	num_vdefs to num_v_may_defs.
	(compute_immediate_uses_for_stmt): Rename occurences of vdef
	to v_may_def.
	(redirect_immediate_uses): Ditto.
	(dump_dfa_stats): Ditto. Also added code to dump num_v_must_defs.
	(collect_dfa_stats_r): Rename occurences of vdef to v_may_def.
	Also add code to sum up the number of v_must_defs.
	(vdefs_disappeared_p): Replace with...
	(v_may_defs_disappeared_p): This.
	(v_must_defs_disappeared_p): New function.
	(mark_new_vars_to_rename): Rename occurences of vdef to v_may_def.
	Also add code to mark new variables found in V_MUST_DEFs for
	renameing.
	* tree-flow.h (stmt_ann_d): Add v_must_def_ops and replace
	vdef_ops to v_may_def_ops.
	(get_vdef_ops): Replace with...
	(get_v_may_def_ops): This.
	* tree-flow-inline.h (get_vdef_ops): Replace with...
	(get_v_may_def_ops): This.
	(get_v_must_def_ops): New function.
	(get_vdef_result_ptr): Replace with...
	(get_v_may_def_result_ptr): This.
	(get_vdef_op_ptr): Ditto with...
	(get_v_may_def_op_ptr); This.
	(get_v_must_def_op_ptr): New function.
	* tree-into-ssa.c (mark_def_sites): Rename occurences of vdef
	to v_may_def. Also add code to mark statements with
	V_MUST_DEFs as definition sites.
	(rewrite_stmt): Rename occurences of vdef to v_may_def. Also
	add code to register new V_MUST_DEFs made by the statement.
	* tree-outof-ssa.c (VIRTUAL_PARTITION): Update comments.
	(check_replaceable): Rename occurences of vdef to v_may_def. Also
	add check for V_MUST_DEFs.
	(find_replaceable_in_bb): Ditto.
	* tree-pretty-print.c (dump_vops): Rename occurences of vdef
	to v_may_def. Also add code to dump V_MUST_DEFs.
	* tree-sra.c (mark_all_vdefs): Replace with...
	(mark_all_v_may_defs): This.
	(mark_all_v_must_defs): New function.
	(create_scalar_copies): Replace call to mark_all_vdefs with
	calls to mark_all_v_may_defs and mark_all_v_must_defs.
	(scalarize_structures): Rename occurences of vdef to v_may_def.
	Also add a check for V_MUST_DEFs.
	(scalarize_modify_expr): Rename occurences of vdef to v_may_def.
	* tree-ssa-alias.c (global_var): Update comment.
	(compute_may_aliases): Ditto.
	(compute_points_to_and_addr_escape): Rename occurences of vdef
	to v_may_def. Also add code to mark variables in V_MUST_DEF
	operands as being written to.
	(group_aliases): Update comment.
	(maybe_create_global_var): Ditto.
	* tree-ssa.c (verify_ssa): Rename occurences of vdef to v_may_def.
	Also add a check for V_MUST_DEFs on GIMPLE registers.
	(replace_immediate_uses): Rename occurences of vdef to v_may_def.
	* tree-ssa-ccp.c (visit_stmt): Rename occurences of vdef
	to v_may_def. Also add code to mark all V_MUST_DEF operands
	VARYING.
	(initialize): Ditto.
	(set_rhs): Rename occurences of vdef to v_may_def. Also add
	code to update SSA_NAMEs in V_MUST_DEFs.
	* tree-ssa-copy.c (cprop_into_stmt): Rename occurences of vdef
	to v_may_def.
	* tree-ssa-dce.c (mark_stmt_if_obviously_necessary): Rename
	occurences of vdef to v_may_def. Also add code to mark statements
	with V_MUST_DEFs as necessary.
	(propagate_necessity): Rename occurences of vdef to v_may_def.
	* tree-ssa-dom.c (redirect_edges_and_update_ssa_graph): Rename
	occurences of vdef to v_may_def. Also add code to mark operands
	in V_MUST_DEFs for renaming.
	(eliminate_redundant_computations): Rename occurences of vdef
	to v_may_def.
	(record_equivalences_from_stmt): Rename occurences of vdef
	to v_may_def. Also add code to record VUSEs for V_MUST_DEFs.
	(optimize_stmt): Remove unnesessary variable vdefs. Update
	comment.
	(register_definitions_for_stmt): Rename occurences of vdef
	to v_may_def. Also add code to register definitions made with
	V_MUST_DEFs.
	* tree-ssa-dse.c (fix_stmt_vdefs): Replace with...
	(fix_stmt_v_may_defs): This.
	(fix_phi_uses): Rename occurences of vdef to v_may_def.
	(dse_optimize_stmt): Ditto.
	* tree-ssa-live.c (create_ssa_var_map): Rename occurences of vdef
	to v_may_def. Also add code to mark V_MUST_DEF operands as being
	used in virtual operators.
	* tree-ssa-loop.c (mark_defs_for_rewrite): Rename occurences of
	vdef to v_may_def. Also add code to mark V_MUST_DEF operands for
	renaming.
	* tree-ssa-operands.c (opf_kill_def): New flag for killing
	definitions.
	(build_vdefs): Renamed to...
	(build_v_may_defs): This.
	(build_v_must_defs): New variable.
	(voperands_d): Add v_must_def_ops and replace vdef_ops with
	v_may_def_ops.
	(append_vdef): Replace with...
	(append_v_may_def): This.
	(append_v_must_def): New function.
	(NUM_FREE): Increment for V_MUST_DEF
	(optype_freelist): Increment its size for V_MUST_DEF
	(allocate_vdef_optype): Replace with...
	(allocate_v_may_def_optype): This.
	(allocate_v_must_def_optype): New function.
	(free_vdefs): Replace with...
	(free_v_may_defs): This.
	(free_v_must_defs): New function.
	(remove_vdefs): Replace with...
	(remove_v_may_defs): This.
	(remove_v_must_defs): New function.
	(init_ssa_operands): Rename occurences of vdef to v_may_def. Also
	add code to initialize build_v_must_defs.
	(finalize_ssa_vdefs): Replace with...
	(finalize_ssa_v_may_defs): This.
	(finalize_ssa_vuses): Rename occurences of vdef to v_may_def.
	(finalize_ssa_v_must_defs): New function.
	(finalize_ssa_stmt_operands): Replace call to finalize_ssa_vdefs
	with calls to finalize_ssa_v_may_defs and finalize_ssa_v_must_defs.
	(verify_start_operands): Rename occurences of vdef to v_may_def.
	Also add check for build_v_must_defs.
	(get_stmt_operands): Rename occurences of vdef to v_may_def.
	Also add code to handle V_MUST_DEFs and to use opf_kill_def for
	killing definitions.
	(get_expr_operands): Update comment and use opf_kill_def for
	killing definitions.
	(add_stmt_operand): Replace code that appends VDEFs with code
	that appends V_MUST_DEFs when opf_kill_def is set and V_MAY_DEFs
	otherwise.
	(add_call_clobber_ops): Update comments.
	* tree-ssa-operands.h (vdef_optype_d): Replace with...
	(v_may_def_optype_d): This.
	(v_must_def_optype_d): New structure.
	(VDEF_OPS): Replace with...
	(V_MAY_DEF_OPS): This.
	(STMT_VDEF_OPS): Same with...
	(STMT_V_MAY_DEF_OPS): This.
	(NUM_VDEFS): And...
	(NUM_V_MAY_DEFS): This.
	(VDEF_RESULT_PTR): As well as...
	(V_MAY_DEF_RESULT_PTR): This.
	(VDEF_RESULT): Same goes for...
	(V_MAY_DEF_RESULT): This.
	(VDEF_OP_PTR): And...
	(V_MAY_DEF_OP_PTR): This.
	(VDEF_OP): And...
	(V_MAY_DEF_OP): This.
	(V_MUST_DEF_OPS): New macro.
	(STMT_V_MUST_DEF_OPS): Ditto.
	(NUM_V_MUST_DEFS): Ditto.
	(V_MUST_DEF_OP_PTR): Ditto.
	(V_MUST_DEF_OP): Ditto.
	(remove_vdefs): Replace signature with...
	(remove_v_may_defs): This.
	(remove_v_must_defs): New function signature.
	* tree-ssa-pre.c (subst_phis): Replace call to remove_vdefs
	with calls to remove_v_may_defs and remove_v_must_defs.
	(process_left_occs_and_kills): Rename occurences of vdef to v_may_def.
	Also add code that marks left occurences of operands in V_MUST_DEFs.
	* tree-tailcall.c (find_tail_calls): Rename occurences of vdef
	to v_may_def. Also add check for V_MUST_DEFs.
	(eliminate_tail_call):Rename occurences of vdef to v_may_def.

testsuite:

	* gcc.dg/tree-ssa/20031015-1.c: Scan for
	V_MAY_DEF instead of VDEF.
	* gcc.dg/tree-ssa/20040517-1.c: Ditto.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@82947 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 81 insertions, 27 deletions

diff --git a/gcc/tree-dfa.c b/gcc/tree-dfa.c
index 00d008fbaaf..3bcf1d525c9 100644
--- a/gcc/tree-dfa.c
+++ b/gcc/tree-dfa.c
@@ -59,8 +59,9 @@ struct dfa_stats_d
   long num_phis;
   long num_phi_args;
   int max_num_phi_args;
-  long num_vdefs;
+  long num_v_may_defs;
   long num_vuses;
+  long num_v_must_defs;
 };
 
 
@@ -280,7 +281,7 @@ compute_immediate_uses_for_stmt (tree stmt, int flags, bool (*calc_for)(tree))
   size_t i;
   use_optype uses;
   vuse_optype vuses;
-  vdef_optype vdefs;
+  v_may_def_optype v_may_defs;
   stmt_ann_t ann;
 
 #ifdef ENABLE_CHECKING
@@ -314,10 +315,10 @@ compute_immediate_uses_for_stmt (tree stmt, int flags, bool (*calc_for)(tree))
 	    add_immediate_use (imm_rdef_stmt, stmt);
 	}
 
-      vdefs = VDEF_OPS (ann);
-      for (i = 0; i < NUM_VDEFS (vdefs); i++)
+      v_may_defs = V_MAY_DEF_OPS (ann);
+      for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
 	{
-	  tree vuse = VDEF_OP (vdefs, i);
+	  tree vuse = V_MAY_DEF_OP (v_may_defs, i);
 	  tree imm_rdef_stmt = SSA_NAME_DEF_STMT (vuse);
 	  if (!IS_EMPTY_STMT (imm_rdef_stmt) && (!calc_for || calc_for (vuse)))
 	    add_immediate_use (imm_rdef_stmt, stmt);
@@ -390,7 +391,7 @@ redirect_immediate_uses (tree old, tree new)
   stmt_ann_t ann = get_stmt_ann (old);
   use_optype uses = USE_OPS (ann);
   vuse_optype vuses = VUSE_OPS (ann);
-  vdef_optype vdefs = VDEF_OPS (ann);
+  v_may_def_optype v_may_defs = V_MAY_DEF_OPS (ann);
   unsigned int i;
 
   /* Look at USE_OPS or VUSE_OPS according to FLAGS.  */
@@ -400,8 +401,8 @@ redirect_immediate_uses (tree old, tree new)
   for (i = 0; i < NUM_VUSES (vuses); i++)
     redirect_immediate_use (VUSE_OP (vuses, i), old, new);
 
-  for (i = 0; i < NUM_VDEFS (vdefs); i++)
-    redirect_immediate_use (VDEF_OP (vdefs, i), old, new);
+  for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
+    redirect_immediate_use (V_MAY_DEF_OP (v_may_defs, i), old, new);
 }
 
 
@@ -699,9 +700,14 @@ dump_dfa_stats (FILE *file)
   fprintf (file, fmt_str_1, "VUSE operands", dfa_stats.num_vuses,
 	   SCALE (size), LABEL (size));
 
-  size = dfa_stats.num_vdefs * sizeof (tree *);
+  size = dfa_stats.num_v_may_defs * sizeof (tree *);
   total += size;
-  fprintf (file, fmt_str_1, "VDEF operands", dfa_stats.num_vdefs,
+  fprintf (file, fmt_str_1, "V_MAY_DEF operands", dfa_stats.num_v_may_defs,
+	   SCALE (size), LABEL (size));
+	   
+  size = dfa_stats.num_v_must_defs * sizeof (tree *);
+  total += size;
+  fprintf (file, fmt_str_1, "V_MUST_DEF operands", dfa_stats.num_v_must_defs,
 	   SCALE (size), LABEL (size));
 
   size = dfa_stats.num_phis * sizeof (struct tree_phi_node);
@@ -797,8 +803,11 @@ collect_dfa_stats_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
 	    dfa_stats_p->num_stmt_anns++;
 	    dfa_stats_p->num_defs += NUM_DEFS (DEF_OPS (ann));
 	    dfa_stats_p->num_uses += NUM_USES (USE_OPS (ann));
-	    dfa_stats_p->num_vdefs += NUM_VDEFS (VDEF_OPS (ann));
+	    dfa_stats_p->num_v_may_defs += 
+	                 NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann));
 	    dfa_stats_p->num_vuses += NUM_VUSES (VUSE_OPS (ann));
+	    dfa_stats_p->num_v_must_defs += 
+	                 NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann));
 	    break;
 	  }
 
@@ -1012,21 +1021,43 @@ add_referenced_tmp_var (tree var)
   add_referenced_var (var, NULL);
 }
 
+/* Return true if V_MAY_DEFS_AFTER contains fewer entries than 
+   V_MAY_DEFS_BEFORE. Note that this assumes that both varrays 
+   are V_MAY_DEF operands for the same statement.  */
+
+static inline bool
+v_may_defs_disappeared_p (v_may_def_optype v_may_defs_before, 
+                          v_may_def_optype v_may_defs_after)
+{
+  /* If there was nothing before, nothing could've disappeared.  */
+  if (v_may_defs_before == NULL)
+    return false;
+     
+  /* All/some of them gone.  */
+  if (v_may_defs_after == NULL
+      || NUM_V_MAY_DEFS (v_may_defs_before) > 
+         NUM_V_MAY_DEFS (v_may_defs_after))
+    return true;
+
+  return false;
+}
 
-/* Return true if VDEFS_AFTER contains fewer entries than VDEFS_BEFORE.
-   Note that this assumes that both varrays are VDEF operands for the same
-   statement.  */
+/* Return true if V_MUST_DEFS_AFTER contains fewer entries than 
+   V_MUST_DEFS_BEFORE. Note that this assumes that both varrays 
+   are V_MUST_DEF operands for the same statement.  */
 
 static inline bool
-vdefs_disappeared_p (vdef_optype vdefs_before, vdef_optype vdefs_after)
+v_must_defs_disappeared_p (v_must_def_optype v_must_defs_before, 
+                           v_must_def_optype v_must_defs_after)
 {
   /* If there was nothing before, nothing could've disappeared.  */
-  if (vdefs_before == NULL)
+  if (v_must_defs_before == NULL)
     return false;
      
   /* All/some of them gone.  */
-  if (vdefs_after == NULL
-      || NUM_VDEFS (vdefs_before) > NUM_VDEFS (vdefs_after))
+  if (v_must_defs_after == NULL
+      || NUM_V_MUST_DEFS (v_must_defs_before) > 
+         NUM_V_MUST_DEFS (v_must_defs_after))
     return true;
 
   return false;
@@ -1041,12 +1072,14 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
 {
   def_optype defs;
   use_optype uses;
-  vdef_optype vdefs;
+  v_may_def_optype v_may_defs;
   vuse_optype vuses;
+  v_must_def_optype v_must_defs;
   size_t i;
   bitmap vars_in_vops_to_rename;
   bool found_exposed_symbol = false;
-  vdef_optype vdefs_before, vdefs_after;
+  v_may_def_optype v_may_defs_before, v_may_defs_after;
+  v_must_def_optype v_must_defs_before, v_must_defs_after;
   stmt_ann_t ann;
 
   vars_in_vops_to_rename = BITMAP_XMALLOC ();
@@ -1061,10 +1094,10 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
      rename them if there are not any newly exposed symbols in the
      statement operands.  */
   ann = stmt_ann (stmt);
-  vdefs_before = vdefs = VDEF_OPS (ann);
-  for (i = 0; i < NUM_VDEFS (vdefs); i++)
+  v_may_defs_before = v_may_defs = V_MAY_DEF_OPS (ann);
+  for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
     {
-      tree var = VDEF_RESULT (vdefs, i);
+      tree var = V_MAY_DEF_RESULT (v_may_defs, i);
       if (!DECL_P (var))
 	var = SSA_NAME_VAR (var);
       bitmap_set_bit (vars_in_vops_to_rename, var_ann (var)->uid);
@@ -1079,6 +1112,15 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
       bitmap_set_bit (vars_in_vops_to_rename, var_ann (var)->uid);
     }
 
+  v_must_defs_before = v_must_defs = V_MUST_DEF_OPS (ann);
+  for (i = 0; i < NUM_V_MUST_DEFS (v_must_defs); i++)
+    {
+      tree var = V_MUST_DEF_OP (v_must_defs, i);
+      if (!DECL_P (var))
+	var = SSA_NAME_VAR (var);
+      bitmap_set_bit (vars_in_vops_to_rename, var_ann (var)->uid);
+    }
+
   /* Now force an operand re-scan on the statement and mark any newly
      exposed variables.  */
   modify_stmt (stmt);
@@ -1106,10 +1148,10 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
 	}
     }
 
-  vdefs_after = vdefs = VDEF_OPS (ann);
-  for (i = 0; i < NUM_VDEFS (vdefs); i++)
+  v_may_defs_after = v_may_defs = V_MAY_DEF_OPS (ann);
+  for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
     {
-      tree var = VDEF_RESULT (vdefs, i);
+      tree var = V_MAY_DEF_RESULT (v_may_defs, i);
       if (DECL_P (var))
 	{
 	  found_exposed_symbol = true;
@@ -1127,6 +1169,17 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
 	  bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
 	}
     }
+    
+  v_must_defs_after = v_must_defs = V_MUST_DEF_OPS (ann);
+  for (i = 0; i < NUM_V_MUST_DEFS (v_must_defs); i++)
+    {
+      tree var = V_MUST_DEF_OP (v_must_defs, i);
+      if (DECL_P (var))
+	{
+	  found_exposed_symbol = true;
+	  bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
+	}
+    }  
 
   /* If we found any newly exposed symbols, or if there are fewer VDEF
      operands in the statement, add the variables we had set in
@@ -1134,7 +1187,8 @@ mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
      vanishing VDEFs because in those cases, the names that were formerly
      generated by this statement are not going to be available anymore.  */
   if (found_exposed_symbol
-      || vdefs_disappeared_p (vdefs_before, vdefs_after))
+      || v_may_defs_disappeared_p (v_may_defs_before, v_may_defs_after)
+      || v_must_defs_disappeared_p (v_must_defs_before, v_must_defs_after))
     bitmap_a_or_b (vars_to_rename, vars_to_rename, vars_in_vops_to_rename);
 
   BITMAP_XFREE (vars_in_vops_to_rename);