tree-ssa-live.h (find_replaceable_exprs, [...]): Move prototypes to...

2013-09-26  Andrew MacLeod  <amacleod@redhat.com>

	* tree-ssa-live.h (find_replaceable_exprs, dump_replaceable_exprs): Move
	prototypes to...
	* tree-ssa-ter.h: New File.  Move prototypes here.
	* tree-flow.h (stmt_is_replaceable_p): Remove prototype.
	* tree-outof-ssa.h: New. Rename ssaexpand.h, include tree-ssa-ter.h.
	* tree-outof-ssa.c (ssa_is_replaceable_p): New.  Refactor common bits
	from is_replaceable_p. 
	* tree-ssa-ter.c (is_replaceable_p, stmt_is_replaceable_p): Delete.
	(ter_is_replaceable_p): New.  Use new refactored ssa_is_replaceable_p.
	(process_replaceable): Use ter_is_replaceable_p.
	(find_replaceable_in_bb): Use ter_is_replaceable_p.
	* expr.c (stmt_is_replaceable_p): Relocate from tree-ssa-ter.c.  Use
	newly refactored ssa_is_replaceable_p.
	* cfgexpand.c: Include tree-outof-ssa.h.
	* ssaexpand.h: Delete.

From-SVN: r202946

9 files changed, 211 insertions, 125 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index eb83ea89323..f69ae29ae1b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,21 @@
+2013-09-26  Andrew MacLeod  <amacleod@redhat.com>
+
+	* tree-ssa-live.h (find_replaceable_exprs, dump_replaceable_exprs): Move
+	prototypes to...
+	* tree-ssa-ter.h: New File.  Move prototypes here.
+	* tree-flow.h (stmt_is_replaceable_p): Remove prototype.
+	* tree-outof-ssa.h: New. Rename ssaexpand.h, include tree-ssa-ter.h.
+	* tree-outof-ssa.c (ssa_is_replaceable_p): New.  Refactor common bits
+	from is_replaceable_p. 
+	* tree-ssa-ter.c (is_replaceable_p, stmt_is_replaceable_p): Delete.
+	(ter_is_replaceable_p): New.  Use new refactored ssa_is_replaceable_p.
+	(process_replaceable): Use ter_is_replaceable_p.
+	(find_replaceable_in_bb): Use ter_is_replaceable_p.
+	* expr.c (stmt_is_replaceable_p): Relocate from tree-ssa-ter.c.  Use
+	newly refactored ssa_is_replaceable_p.
+	* cfgexpand.c: Include tree-outof-ssa.h.
+	* ssaexpand.h: Delete.
+
 2013-09-26  Andrew MacLeod <amacleod@redhat.com>
 
 	* gimple.c (gimple_replace_lhs): Move to tree-ssa.c and rename.
diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index 88e48c2a342..f76e5f20b0e 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -40,7 +40,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-inline.h"
 #include "value-prof.h"
 #include "target.h"
-#include "ssaexpand.h"
+#include "tree-outof-ssa.h"
 #include "bitmap.h"
 #include "sbitmap.h"
 #include "cfgloop.h"
diff --git a/gcc/expr.c b/gcc/expr.c
index 5949b131e41..235cd677e3a 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -49,7 +49,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "timevar.h"
 #include "df.h"
 #include "diagnostic.h"
-#include "ssaexpand.h"
+#include "tree-outof-ssa.h"
 #include "target-globals.h"
 #include "params.h"
 
@@ -9126,6 +9126,24 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
 }
 #undef REDUCE_BIT_FIELD
 
+
+/* Return TRUE if expression STMT is suitable for replacement.  
+   Never consider memory loads as replaceable, because those don't ever lead 
+   into constant expressions.  */
+
+static bool
+stmt_is_replaceable_p (gimple stmt)
+{
+  if (ssa_is_replaceable_p (stmt))
+    {
+      /* Don't move around loads.  */
+      if (!gimple_assign_single_p (stmt)
+	  || is_gimple_val (gimple_assign_rhs1 (stmt)))
+	return true;
+    }
+  return false;
+}
+
 rtx
 expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 		    enum expand_modifier modifier, rtx *alt_rtl)
diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h
index ee691791aae..cf96817649c 100644
--- a/gcc/tree-flow.h
+++ b/gcc/tree-flow.h
@@ -679,9 +679,6 @@ bool fixup_noreturn_call (gimple stmt);
 /* In ipa-pure-const.c  */
 void warn_function_noreturn (tree);
 
-/* In tree-ssa-ter.c  */
-bool stmt_is_replaceable_p (gimple);
-
 /* In tree-parloops.c  */
 bool parallelized_function_p (tree);
 
diff --git a/gcc/tree-outof-ssa.c b/gcc/tree-outof-ssa.c
index 5ed145db024..42c90d49a18 100644
--- a/gcc/tree-outof-ssa.c
+++ b/gcc/tree-outof-ssa.c
@@ -30,12 +30,67 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-ssa.h"
 #include "dumpfile.h"
 #include "diagnostic-core.h"
-#include "ssaexpand.h"
+#include "tree-outof-ssa.h"
 
 /* FIXME: A lot of code here deals with expanding to RTL.  All that code
    should be in cfgexpand.c.  */
 #include "expr.h"
 
+/* Return TRUE if expression STMT is suitable for replacement.  */
+
+bool
+ssa_is_replaceable_p (gimple stmt)
+{
+  use_operand_p use_p;
+  tree def;
+  gimple use_stmt;
+
+  /* Only consider modify stmts.  */
+  if (!is_gimple_assign (stmt))
+    return false;
+
+  /* If the statement may throw an exception, it cannot be replaced.  */
+  if (stmt_could_throw_p (stmt))
+    return false;
+
+  /* Punt if there is more than 1 def.  */
+  def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
+  if (!def)
+    return false;
+
+  /* Only consider definitions which have a single use.  */
+  if (!single_imm_use (def, &use_p, &use_stmt))
+    return false;
+
+  /* Used in this block, but at the TOP of the block, not the end.  */
+  if (gimple_code (use_stmt) == GIMPLE_PHI)
+    return false;
+
+  /* There must be no VDEFs.  */
+  if (gimple_vdef (stmt))
+    return false;
+
+  /* Float expressions must go through memory if float-store is on.  */
+  if (flag_float_store
+      && FLOAT_TYPE_P (gimple_expr_type (stmt)))
+    return false;
+
+  /* An assignment with a register variable on the RHS is not
+     replaceable.  */
+  if (gimple_assign_rhs_code (stmt) == VAR_DECL
+      && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt)))
+    return false;
+
+  /* No function calls can be replaced.  */
+  if (is_gimple_call (stmt))
+    return false;
+
+  /* Leave any stmt with volatile operands alone as well.  */
+  if (gimple_has_volatile_ops (stmt))
+    return false;
+
+  return true;
+}
 
 
 /* Used to hold all the components required to do SSA PHI elimination.
diff --git a/gcc/ssaexpand.h b/gcc/tree-outof-ssa.h
index 0bdc8d48097..d0af95f0f3b 100644
--- a/gcc/ssaexpand.h
+++ b/gcc/tree-outof-ssa.h
@@ -22,6 +22,7 @@ along with GCC; see the file COPYING3.  If not see
 #define _SSAEXPAND_H 1
 
 #include "tree-ssa-live.h"
+#include "tree-ssa-ter.h"
 
 /* This structure (of which only a singleton SA exists) is used to
    pass around information between the outof-SSA functions, cfgexpand
@@ -71,9 +72,9 @@ get_gimple_for_ssa_name (tree exp)
   return NULL;
 }
 
-/* In tree-outof-ssa.c.  */
-void finish_out_of_ssa (struct ssaexpand *sa);
-unsigned int rewrite_out_of_ssa (struct ssaexpand *sa);
-void expand_phi_nodes (struct ssaexpand *sa);
+extern bool ssa_is_replaceable_p (gimple stmt);
+extern void finish_out_of_ssa (struct ssaexpand *sa);
+extern unsigned int rewrite_out_of_ssa (struct ssaexpand *sa);
+extern void expand_phi_nodes (struct ssaexpand *sa);
 
 #endif
diff --git a/gcc/tree-ssa-live.h b/gcc/tree-ssa-live.h
index 8fd1e80d549..542f6a1944e 100644
--- a/gcc/tree-ssa-live.h
+++ b/gcc/tree-ssa-live.h
@@ -325,10 +325,4 @@ make_live_on_entry (tree_live_info_p live, basic_block bb , int p)
 /* From tree-ssa-coalesce.c  */
 extern var_map coalesce_ssa_name (void);
 
-
-/* From tree-ssa-ter.c  */
-extern bitmap find_replaceable_exprs (var_map);
-extern void dump_replaceable_exprs (FILE *, bitmap);
-
-
 #endif /* _TREE_SSA_LIVE_H  */
diff --git a/gcc/tree-ssa-ter.c b/gcc/tree-ssa-ter.c
index ee18cd8f164..3659cf0c428 100644
--- a/gcc/tree-ssa-ter.c
+++ b/gcc/tree-ssa-ter.c
@@ -28,7 +28,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "bitmap.h"
 #include "tree-ssa.h"
 #include "dumpfile.h"
-#include "tree-ssa-live.h"
+#include "tree-outof-ssa.h"
 #include "flags.h"
 
 
@@ -46,7 +46,7 @@ along with GCC; see the file COPYING3.  If not see
    information is tracked.
 
    Variables which only have one use, and whose defining stmt is considered
-   a replaceable expression (see is_replaceable_p) are tracked to see whether
+   a replaceable expression (see ssa_is_replaceable_p) are tracked to see whether
    they can be replaced at their use location.
 
    n_12 = C * 10
@@ -359,111 +359,6 @@ add_dependence (temp_expr_table_p tab, int version, tree var)
 }
 
 
-/* Return TRUE if expression STMT is suitable for replacement.
-   TER is true if is_replaceable_p is called from within TER, false
-   when used from within stmt_is_replaceable_p, i.e. EXPAND_INITIALIZER
-   expansion.  The differences are that with !TER some tests are skipped
-   to make it more aggressive (doesn't require the same bb, or for -O0
-   same locus and same BLOCK), on the other side never considers memory
-   loads as replaceable, because those don't ever lead into constant
-   expressions.  */
-
-static inline bool
-is_replaceable_p (gimple stmt, bool ter)
-{
-  use_operand_p use_p;
-  tree def;
-  gimple use_stmt;
-  location_t locus1, locus2;
-  tree block1, block2;
-
-  /* Only consider modify stmts.  */
-  if (!is_gimple_assign (stmt))
-    return false;
-
-  /* If the statement may throw an exception, it cannot be replaced.  */
-  if (stmt_could_throw_p (stmt))
-    return false;
-
-  /* Punt if there is more than 1 def.  */
-  def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
-  if (!def)
-    return false;
-
-  /* Only consider definitions which have a single use.  */
-  if (!single_imm_use (def, &use_p, &use_stmt))
-    return false;
-
-  /* If the use isn't in this block, it wont be replaced either.  */
-  if (ter && gimple_bb (use_stmt) != gimple_bb (stmt))
-    return false;
-
-  locus1 = gimple_location (stmt);
-  block1 = LOCATION_BLOCK (locus1);
-  locus1 = LOCATION_LOCUS (locus1);
-
-  if (gimple_code (use_stmt) == GIMPLE_PHI)
-    locus2 = gimple_phi_arg_location (use_stmt, PHI_ARG_INDEX_FROM_USE (use_p));
-  else
-    locus2 = gimple_location (use_stmt);
-  block2 = LOCATION_BLOCK (locus2);
-  locus2 = LOCATION_LOCUS (locus2);
-
-  if ((!optimize || optimize_debug)
-      && ter
-      && ((locus1 != UNKNOWN_LOCATION
-	   && locus1 != locus2)
-	  || (block1 != NULL_TREE
-	      && block1 != block2)))
-    return false;
-
-  /* Used in this block, but at the TOP of the block, not the end.  */
-  if (gimple_code (use_stmt) == GIMPLE_PHI)
-    return false;
-
-  /* There must be no VDEFs.  */
-  if (gimple_vdef (stmt))
-    return false;
-
-  /* Without alias info we can't move around loads.  */
-  if ((!optimize || !ter)
-      && gimple_assign_single_p (stmt)
-      && !is_gimple_val (gimple_assign_rhs1 (stmt)))
-    return false;
-
-  /* Float expressions must go through memory if float-store is on.  */
-  if (flag_float_store
-      && FLOAT_TYPE_P (gimple_expr_type (stmt)))
-    return false;
-
-  /* An assignment with a register variable on the RHS is not
-     replaceable.  */
-  if (gimple_assign_rhs_code (stmt) == VAR_DECL
-      && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt)))
-    return false;
-
-  /* No function calls can be replaced.  */
-  if (is_gimple_call (stmt))
-    return false;
-
-  /* Leave any stmt with volatile operands alone as well.  */
-  if (gimple_has_volatile_ops (stmt))
-    return false;
-
-  return true;
-}
-
-
-/* Variant of is_replaceable_p test for use in EXPAND_INITIALIZER
-   expansion.  */
-
-bool
-stmt_is_replaceable_p (gimple stmt)
-{
-  return is_replaceable_p (stmt, false);
-}
-
-
 /* This function will remove the expression for VERSION from replacement
    consideration in table TAB.  If FREE_EXPR is true, then remove the
    expression from consideration as well by freeing the decl uid bitmap.  */
@@ -487,6 +382,62 @@ finished_with_expr (temp_expr_table_p tab, int version, bool free_expr)
 }
 
 
+/* Return TRUE if expression STMT is suitable for replacement.
+   In addition to ssa_is_replaceable_p, require the same bb, and for -O0
+   same locus and same BLOCK), Considers memory loads as replaceable if aliasing
+   is available.  */
+
+static inline bool
+ter_is_replaceable_p (gimple stmt)
+{
+
+  if (ssa_is_replaceable_p (stmt))
+    {
+      use_operand_p use_p;
+      tree def;
+      gimple use_stmt;
+      location_t locus1, locus2;
+      tree block1, block2;
+
+      /* Only consider definitions which have a single use.  ssa_is_replaceable_p
+	 already performed this check, but the use stmt pointer is required for
+	 further checks.  */
+      def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
+      if (!single_imm_use (def, &use_p, &use_stmt))
+	  return false;
+
+      /* If the use isn't in this block, it wont be replaced either.  */
+      if (gimple_bb (use_stmt) != gimple_bb (stmt))
+        return false;
+
+      locus1 = gimple_location (stmt);
+      block1 = LOCATION_BLOCK (locus1);
+      locus1 = LOCATION_LOCUS (locus1);
+
+      if (gimple_code (use_stmt) == GIMPLE_PHI)
+	locus2 = gimple_phi_arg_location (use_stmt, 
+					  PHI_ARG_INDEX_FROM_USE (use_p));
+      else
+	locus2 = gimple_location (use_stmt);
+      block2 = LOCATION_BLOCK (locus2);
+      locus2 = LOCATION_LOCUS (locus2);
+
+      if ((!optimize || optimize_debug)
+	  && ((locus1 != UNKNOWN_LOCATION && locus1 != locus2)
+	      || (block1 != NULL_TREE && block1 != block2)))
+	return false;
+
+      /* Without alias info we can't move around loads.  */
+      if (!optimize && gimple_assign_single_p (stmt)
+	  && !is_gimple_val (gimple_assign_rhs1 (stmt)))
+	return false;
+
+      return true;
+    }
+  return false;
+}
+
+
 /* Create an expression entry for a replaceable expression.  */
 
 static void
@@ -497,7 +448,7 @@ process_replaceable (temp_expr_table_p tab, gimple stmt, int call_cnt)
   ssa_op_iter iter;
   bitmap def_vars, use_vars;
 
-  gcc_checking_assert (is_replaceable_p (stmt, true));
+  gcc_checking_assert (ter_is_replaceable_p (stmt));
 
   def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
   version = SSA_NAME_VERSION (def);
@@ -612,7 +563,7 @@ find_replaceable_in_bb (temp_expr_table_p tab, basic_block bb)
       if (is_gimple_debug (stmt))
 	continue;
 
-      stmt_replaceable = is_replaceable_p (stmt, true);
+      stmt_replaceable = ter_is_replaceable_p (stmt);
 
       /* Determine if this stmt finishes an existing expression.  */
       FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
diff --git a/gcc/tree-ssa-ter.h b/gcc/tree-ssa-ter.h
new file mode 100644
index 00000000000..4565db16b86
--- /dev/null
+++ b/gcc/tree-ssa-ter.h
@@ -0,0 +1,52 @@
+/* Header file for tree-ssa-ter.c exports.
+   Copyright (C) 2013 Free Software Foundation, Inc.
+
+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 3, 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 COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_TREE_SSA_TER_H
+#define GCC_TREE_SSA_TER_H
+
+extern bitmap find_replaceable_exprs (var_map);
+extern void dump_replaceable_exprs (FILE *, bitmap);
+
+#endif /* GCC_TREE_SSA_TER_H */
+/* Header file for tree-ssa-ter.c exports.
+   Copyright (C) 2013 Free Software Foundation, Inc.
+
+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 3, 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 COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_TREE_SSA_TER_H
+#define GCC_TREE_SSA_TER_H
+
+extern bitmap find_replaceable_exprs (var_map);
+extern void dump_replaceable_exprs (FILE *, bitmap);
+
+#endif /* GCC_TREE_SSA_TER_H */