2004-10-01 Jakub Jelinek <jakub@redhat.com>

	Revert
	2004-09-29  Jakub Jelinek  <jakub@redhat.com>

	* tree.h (enum tree_index): Add TI_VA_LIST_GPR_COUNTER_FIELD
	and TI_VA_LIST_FPR_COUNTER_FIELD.
	(va_list_gpr_counter_field, va_list_fpr_counter_field): Define.
	* tree-pass.h (pass_stdarg): Add.
	* tree-optimize.c (init_tree_optimization_passes): Add pass_stdarg.
	* tree-stdarg.c: New file.
	* Makefile.in (OBJS-common): Add tree-stdarg.o.
	(tree-stdarg.o): Add dependencies.
	* function.h (struct function): Add va_list_gpr_size and
	va_list_fpr_size fields.
	* function.c (allocate_struct_function): Initialize them.

	* config/i386/i386.c (ix86_build_builtin_va_list): Initialize
	va_list_{g,f}pr_counter_field.
	(ix86_setup_incoming_varargs): Don't do anything if reg_save
	area will not be used.  Only save registers that tree-stdarg.c
	detected they need saving.
	(ix86_va_start): Don't set up fields that won't be used.

	* config/rs6000/rs6000.c (rs6000_build_builtin_va_list): Initialize
	va_list_{g,f}pr_counter_field.
	(setup_incoming_varargs): Don't do anything if reg_save
	area will not be used.  Only save registers that tree-stdarg.c
	detected they need saving.
	(rs6000_va_start): Don't set up fields that won't be used.

	* gcc.dg/tree-ssa/stdarg-1.c: Removed.
	* gcc.dg/tree-ssa/stdarg-2.c: Removed.
	* gcc.dg/tree-ssa/stdarg-3.c: Removed.
	* gcc.dg/tree-ssa/stdarg-4.c: Removed.
	* gcc.dg/tree-ssa/stdarg-5.c: Removed.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@88383 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 0 insertions, 470 deletions

diff --git a/gcc/tree-stdarg.c b/gcc/tree-stdarg.c
deleted file mode 100644
index 926563793ca..00000000000
--- a/gcc/tree-stdarg.c
+++ /dev/null
@@ -1,470 +0,0 @@
-/* Pass computing data for optimizing stdarg functions.
-   Copyright (C) 2004 Free Software Foundation, Inc.
-   Contributed by Jakub Jelinek <jakub@redhat.com>
-
-This file is part of GCC.
-
-GCC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-GCC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING.  If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.  */
-
-#include "config.h"
-#include "system.h"
-#include "coretypes.h"
-#include "tm.h"
-#include "tree.h"
-#include "function.h"
-#include "langhooks.h"
-#include "diagnostic.h"
-#include "tree-flow.h"
-#include "tree-pass.h"
-
-/* A simple pass that attempts to optimize stdarg functions on architectures
-   that need to save register arguments to stack on entry to stdarg functions.
-   If the function doesn't use any va_start macros, no registers need to
-   be saved.  If va_start macros are used, the va_list variables don't escape
-   the function, it is only necessary to save registers that will be used
-   in va_arg macros.  E.g. if va_arg is only used with integral types
-   in the function, floating point registers don't need to be saved, etc.  */
-
-struct stdarg_info
-{
-  bitmap va_list_vars;
-  basic_block va_start_bb, bb;
-  int compute_sizes, va_start_count;
-};
-
-/* Return true if basic block VA_ARG_BB is dominated by VA_START_BB and
-   is executed at most as many times as VA_START_BB.  */
-
-static bool
-reachable_at_most_once (basic_block va_arg_bb, basic_block va_start_bb)
-{
-  edge *stack, e;
-  edge_iterator ei;
-  int sp;
-  sbitmap visited;
-  bool ret;
-
-  if (va_arg_bb == va_start_bb)
-    return true;
-
-  if (! dominated_by_p (CDI_DOMINATORS, va_arg_bb, va_start_bb))
-    return false;
-
-  stack = xmalloc ((n_basic_blocks + 1) * sizeof (edge));
-  sp = 0;
-
-  visited = sbitmap_alloc (last_basic_block);
-  sbitmap_zero (visited);
-  ret = true;
-
-  FOR_EACH_EDGE (e, ei, va_arg_bb->preds)
-    stack[sp++] = e;
-
-  while (sp)
-    {
-      basic_block src;
-
-      --sp;
-      e = stack[sp];
-      src = e->src;
-
-      if (e->flags & EDGE_COMPLEX)
-	{
-	  ret = false;
-	  break;
-	}
-
-      if (src == va_start_bb)
-	continue;
-
-      /* va_arg_bb can be executed more times than va_start_bb.  */
-      if (src == va_arg_bb)
-	{
-	  ret = false;
-	  break;
-	}
-
-      gcc_assert (src != ENTRY_BLOCK_PTR);
-
-      if (! TEST_BIT (visited, src->index))
-	{
-	  SET_BIT (visited, src->index);
-	  FOR_EACH_EDGE (e, ei, src->preds)
-	    stack[sp++] = e;
-	}
-    }
-
-  free (stack);
-  sbitmap_free (visited);
-  return ret;
-}
-
-
-/* For statement COUNTER = RHS, if RHS is COUNTER + constant,
-   return constant, otherwise return 0.  */
-
-static unsigned HOST_WIDE_INT
-va_list_counter_bump (tree counter, tree rhs)
-{
-  tree plus_stmt = SSA_NAME_DEF_STMT (rhs);
-  tree rhs1, addend, load_stmt, counter1;
-
-  if (TREE_CODE (plus_stmt) != MODIFY_EXPR
-      || TREE_OPERAND (plus_stmt, 0) != rhs)
-    return 0;
-
-  rhs1 = TREE_OPERAND (plus_stmt, 1);
-
-  if (TREE_CODE (rhs1) != PLUS_EXPR
-      || TREE_CODE (TREE_OPERAND (rhs1, 0)) != SSA_NAME
-      || TREE_CODE (TREE_OPERAND (rhs1, 1)) != INTEGER_CST
-      || !host_integerp (TREE_OPERAND (rhs1, 1), 1))
-    return 0;
-
-  addend = TREE_OPERAND (rhs1, 0);
-  load_stmt = SSA_NAME_DEF_STMT (addend);
-
-  if (TREE_CODE (load_stmt) != MODIFY_EXPR
-      || TREE_OPERAND (load_stmt, 0) != addend)
-    return 0;
-
-  counter1 = TREE_OPERAND (load_stmt, 1);
-  if (TREE_CODE (counter) != TREE_CODE (counter1))
-    return 0;
-
-  if (TREE_CODE (counter) == COMPONENT_REF)
-    {
-      if (get_base_address (counter) != get_base_address (counter1)
-	  || TREE_CODE (TREE_OPERAND (counter1, 1)) != FIELD_DECL
-	  || TREE_OPERAND (counter, 1) != TREE_OPERAND (counter1, 1))
-	return 0;
-    }
-  else
-    return 0;
-
-  return tree_low_cst (TREE_OPERAND (rhs1, 1), 1);
-}
-
-
-/* Called by walk_tree to look for references to va_list variables.  */
-
-static tree
-find_va_list_reference (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
-			void *data)
-{
-  bitmap va_list_vars = (bitmap) data;
-  tree var = *tp;
-
-  if (TREE_CODE (var) == SSA_NAME)
-    var = SSA_NAME_VAR (var);
-
-  if (TREE_CODE (var) == VAR_DECL
-      && bitmap_bit_p (va_list_vars, var_ann (var)->uid))
-    return var;
-
-  return NULL_TREE;
-}
-
-
-/* Helper function of va_list_counter_struct_op.  Compute
-  cfun->va_list_{g,f}pr_size.  AP is a va_list GPR/FPR counter,
-  if WRITE_P is true, seen in AP = VAR, otherwise seen in VAR = AP
-  statement.  GPR_P is true if AP is a GPR counter, false if it is
-  a FPR counter.  */
-
-static void
-va_list_counter_op (struct stdarg_info *si, tree ap, tree var, bool gpr_p,
-		    bool write_p)
-{
-  unsigned HOST_WIDE_INT increment;
-
-  if (si->compute_sizes < 0)
-    {
-      si->compute_sizes = 0;
-      if (si->va_start_count == 1
-	  && reachable_at_most_once (si->bb, si->va_start_bb))
-	si->compute_sizes = 1;
-
-      if (dump_file && (dump_flags & TDF_DETAILS))
-	fprintf (dump_file,
-		 "bb%d will %sbe executed at most once for each va_start "
-		 "in bb%d\n", si->bb->index, si->compute_sizes ? "" : "not ",
-		 si->va_start_bb->index);
-    }
-
-  if (write_p
-      && si->compute_sizes
-      && (increment = va_list_counter_bump (ap, var)) != 0)
-    {
-      if (gpr_p && cfun->va_list_gpr_size + increment < VA_LIST_MAX_GPR_SIZE)
-	{
-	  cfun->va_list_gpr_size += increment;
-	  return;
-	}
-
-      if (!gpr_p && cfun->va_list_fpr_size + increment < VA_LIST_MAX_FPR_SIZE)
-	{
-	  cfun->va_list_fpr_size += increment;
-	  return;
-	}
-    }
-
-  if (write_p || !si->compute_sizes)
-    {
-      if (gpr_p)
-	cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
-      else
-	cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
-    }
-}
-
-
-/* If AP is a va_list GPR/FPR counter, compute cfun->va_list_{g,f}pr_size.
-   If WRITE_P is true, AP has been seen in AP = VAR assignment, if WRITE_P
-   is false, AP has been seen in VAR = AP assignment.
-   Return true if the AP = VAR (resp. VAR = AP) statement is a recognized
-   va_arg operation that doesn't cause the va_list variable to escape
-   current function.  */
-
-static bool
-va_list_counter_struct_op (struct stdarg_info *si, tree ap, tree var,
-			   bool write_p)
-{
-  tree base;
-
-  if (TREE_CODE (ap) != COMPONENT_REF
-      || TREE_CODE (TREE_OPERAND (ap, 1)) != FIELD_DECL)
-    return false;
-
-  if (TREE_CODE (var) != SSA_NAME
-      || bitmap_bit_p (si->va_list_vars, var_ann (SSA_NAME_VAR (var))->uid))
-    return false;
-
-  base = get_base_address (ap);
-  if (TREE_CODE (base) != VAR_DECL
-      || !bitmap_bit_p (si->va_list_vars, var_ann (base)->uid))
-    return false;
-
-  if (TREE_OPERAND (ap, 1) == va_list_gpr_counter_field)
-    va_list_counter_op (si, ap, var, true, write_p);
-  else if (TREE_OPERAND (ap, 1) == va_list_fpr_counter_field)
-    va_list_counter_op (si, ap, var, false, write_p);
-
-  return true;
-}
-
-
-/* Return true if this optimization pass should be done.
-   It makes only sense for stdarg functions.  */
-
-static bool
-gate_optimize_stdarg (void)
-{
-  /* This optimization is only for stdarg functions.  */
-  return current_function_stdarg != 0;
-}  
-
-
-/* Entry point to the stdarg optimization pass.  */
-
-static void
-execute_optimize_stdarg (void)
-{
-  basic_block bb;
-  bool va_list_escapes = false;
-  struct stdarg_info si;
-  const char *funcname = NULL;
-
-  cfun->va_list_gpr_size = 0;
-  cfun->va_list_fpr_size = 0;
-  memset (&si, 0, sizeof (si));
-  si.va_list_vars = BITMAP_XMALLOC ();
-
-  if (dump_file)
-    funcname = lang_hooks.decl_printable_name (current_function_decl, 2);
-
-  FOR_EACH_BB (bb)
-    {
-      block_stmt_iterator i;
-
-      for (i = bsi_start (bb); !bsi_end_p (i); bsi_next (&i))
-	{
-	  tree stmt = bsi_stmt (i);
-	  tree call = get_call_expr_in (stmt), callee;
-	  tree ap;
-
-	  if (!call)
-	    continue;
-
-	  callee = get_callee_fndecl (call);
-	  if (!callee
-	      || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
-	      || DECL_FUNCTION_CODE (callee) != BUILT_IN_VA_START)
-	    continue;
-
-	  si.va_start_count++;
-	  ap = TREE_VALUE (TREE_OPERAND (call, 1));
-	  if (TREE_CODE (ap) != ADDR_EXPR
-	      || TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (ap, 0)))
-		 != TYPE_MAIN_VARIANT (va_list_type_node)
-	      || TREE_CODE (TREE_OPERAND (ap, 0)) != VAR_DECL)
-	    {
-	      va_list_escapes = true;
-	      break;
-	    }
-
-	  ap = TREE_OPERAND (ap, 0);	    
-	  if (is_global_var (ap))
-	    {
-	      va_list_escapes = true;
-	      break;
-	    }
-
-	  bitmap_set_bit (si.va_list_vars, var_ann (ap)->uid);
-
-	  /* VA_START_BB will be only used if there is just one
-	     va_start in the function.  */
-	  si.va_start_bb = bb;
-	}
-
-      if (va_list_escapes)
-	break;
-    }
-
-  /* If there were no va_start uses in the function, there is no need to
-     save anything.  */
-  if (si.va_start_count == 0)
-    goto finish;
-
-  /* If some va_list arguments weren't local, we can't optimize.  */
-  if (va_list_escapes)
-    goto finish;
-
-  /* If the backend didn't tell us what the counter fields are, there is
-     nothing more we can do.  */
-  if (va_list_gpr_counter_field == NULL_TREE
-      && va_list_fpr_counter_field == NULL_TREE)
-    {
-      va_list_escapes = true;
-      goto finish;
-    }
-
-  FOR_EACH_BB (bb)
-    {
-      block_stmt_iterator i;
-
-      si.compute_sizes = -1;
-      si.bb = bb;
-      for (i = bsi_start (bb);
-	   !bsi_end_p (i) && !va_list_escapes;
-	   bsi_next (&i))
-	{
-	  tree stmt = bsi_stmt (i);
-	  tree call;
-
-	  /* Don't look at __builtin_va_{start,end}, they are ok.  */
-	  call = get_call_expr_in (stmt);
-	  if (call)
-	    {
-	      tree callee = get_callee_fndecl (call);
-
-	      if (callee
-		  && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL
-		  && (DECL_FUNCTION_CODE (callee) == BUILT_IN_VA_START
-		      || DECL_FUNCTION_CODE (callee) == BUILT_IN_VA_END))
-		continue;
-	    }
-
-	  if (TREE_CODE (stmt) == MODIFY_EXPR)
-	    {
-	      tree lhs = TREE_OPERAND (stmt, 0);
-	      tree rhs = TREE_OPERAND (stmt, 1);
-
-	      if (TREE_CODE (rhs) == WITH_SIZE_EXPR)
-		rhs = TREE_OPERAND (rhs, 0);
-
-	      /* Check for ap[0].field = temp.  */
-	      if (va_list_counter_struct_op (&si, lhs, rhs, true))
-		continue;
-
-	      /* Check for temp = ap[0].field.  */
-	      else if (va_list_counter_struct_op (&si, rhs, lhs, false))
-		continue;
-	    }
-
-	  /* All other uses of va_list are either va_copy (that is not handled
-	     in this optimization), taking address of va_list variable or
-	     passing va_list to other functions (in that case va_list might
-	     escape the function and therefore va_start needs to set it up
-	     fully), or some unexpected use of va_list.  None of these should
-	     happen in a gimplified VA_ARG_EXPR.  */
-	  if (walk_tree (&stmt, find_va_list_reference, si.va_list_vars, NULL))
-	    {
-	      if (dump_file && (dump_flags & TDF_DETAILS))
-		{
-		  fputs ("va_list escapes in ", dump_file);
-		  print_generic_expr (dump_file, stmt, dump_flags);
-		  fputc ('\n', dump_file);
-		}
-	      va_list_escapes = true;
-	    }
-	}
-
-      if (va_list_escapes)
-	break;
-    }
-
-finish:
-  if (va_list_escapes)
-    {
-      cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
-      cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
-    }
-  BITMAP_XFREE (si.va_list_vars);
-  if (dump_file)
-    {
-      fprintf (dump_file, "%s: va_list escapes %d, needs to save ",
-	       funcname, (int) va_list_escapes);
-      if (cfun->va_list_gpr_size >= VA_LIST_MAX_GPR_SIZE)
-	fputs ("all", dump_file);
-      else
-	fprintf (dump_file, "%d", cfun->va_list_gpr_size);
-      fputs (" GPR units and ", dump_file);
-      if (cfun->va_list_fpr_size >= VA_LIST_MAX_FPR_SIZE)
-	fputs ("all", dump_file);
-      else
-	fprintf (dump_file, "%d", cfun->va_list_fpr_size);
-      fputs (" FPR units.\n", dump_file);
-    }
-}
-
-
-struct tree_opt_pass pass_stdarg =
-{
-  "stdarg",				/* name */
-  gate_optimize_stdarg,			/* gate */
-  execute_optimize_stdarg,		/* execute */
-  NULL,					/* sub */
-  NULL,					/* next */
-  0,					/* static_pass_number */
-  0,					/* tv_id */
-  PROP_cfg | PROP_ssa | PROP_alias,	/* properties_required */
-  0,					/* properties_provided */
-  0,					/* properties_destroyed */
-  0,					/* todo_flags_start */
-  TODO_dump_func,			/* todo_flags_finish */
-  0					/* letter */
-};