Makefile.in (lower-subreg.o, [...]): Depend on lower-subreg.h.

gcc/
2012-03-31  Kenneth Zadeck  <zadeck@naturalbridge.com>
	    Richard Sandiford  <r.sandiford@uk.ibm.com>

	* Makefile.in (lower-subreg.o, target-globals.o): Depend on
	lower-subreg.h.
	* lower-subreg.h: New file.
	* target-globals.h (this_target_lower_subreg): Declare.
	(target_globals): Add lower_subreg;
	(restore_target_globals): Restore this_target_lower_subreg.
	* target-globals.c: Include it.
	(default_target_globals): Add default_target_lower_subreg.
	(save_target_globals): Initialize target_lower_subreg.
	* rtl.h (init_lower_subreg): Added declaration.
	* toplev.c (backend_init_target): Call initializer for lower-subreg
	pass.
	* lower-subreg.c (LOG_COSTS, FORCE_LOWERING): New macros.
	(default_target_lower_subreg): New variable.
	(this_target_lower_subreg): Likewise.
	(twice_word_mode, choices): New macros.
	(shift_cost, compute_splitting_shift, compute_costs)
	(init_lower_subreg): New functions.
	(resolve_simple_move): Add speed_p argument.  Check choices.
	(find_pseudo_copy): Don't check the mode size here.
	(resolve_simple_move): Assert the mode size.
	(find_decomposable_shift_zext): Add speed_p argument and return
	a bool.  Check choices.
	(resolve_shift_zext): Add comment.
	(dump_shift_choices, dump_choices): New functions.
	(decompose_multiword_subregs): Dump list of profitable
	transformations.  Add code to skip non profitable transformations.
	Update calls to simple_move and find_decomposable_shift_zext.

Co-Authored-By: Richard Sandiford <r.sandiford@uk.ibm.com>

From-SVN: r187015

gcc/ChangeLog

+2012-05-01  Kenneth Zadeck  <zadeck@naturalbridge.com>
+	    Richard Sandiford  <r.sandiford@uk.ibm.com>
+
+	* Makefile.in (lower-subreg.o, target-globals.o): Depend on
+	lower-subreg.h.
+	* lower-subreg.h: New file.
+	* target-globals.h (this_target_lower_subreg): Declare.
+	(target_globals): Add lower_subreg;
+	(restore_target_globals): Restore this_target_lower_subreg.
+	* target-globals.c: Include it.
+	(default_target_globals): Add default_target_lower_subreg.
+	(save_target_globals): Initialize target_lower_subreg.
+	* rtl.h (init_lower_subreg): Added declaration.
+	* toplev.c (backend_init_target): Call initializer for lower-subreg
+	pass.
+	* lower-subreg.c (LOG_COSTS, FORCE_LOWERING): New macros.
+	(default_target_lower_subreg): New variable.
+	(this_target_lower_subreg): Likewise.
+	(twice_word_mode, choices): New macros.
+	(shift_cost, compute_splitting_shift, compute_costs)
+	(init_lower_subreg): New functions.
+	(resolve_simple_move): Add speed_p argument.  Check choices.
+	(find_pseudo_copy): Don't check the mode size here.
+	(resolve_simple_move): Assert the mode size.
+	(find_decomposable_shift_zext): Add speed_p argument and return
+	a bool.  Check choices.
+	(resolve_shift_zext): Add comment.
+	(dump_shift_choices, dump_choices): New functions.
+	(decompose_multiword_subregs): Dump list of profitable
+	transformations.  Add code to skip non profitable transformations.
+	Update calls to simple_move and find_decomposable_shift_zext.
+
 2012-05-01  Ian Bolton  <ian.bolton@arm.com>
             Sameera Deshpande  <sameera.deshpande@arm.com>
             Greta Yorsh  <greta.yorsh@arm.com>

gcc/Makefile.in

@@ -3428,11 +3428,13 @@ dbgcnt.o: dbgcnt.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(DIAGNOSTIC_CORE_H) $(DB
 lower-subreg.o : lower-subreg.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
    $(MACHMODE_H) $(TM_H) $(RTL_H) $(TM_P_H) $(TIMEVAR_H) $(FLAGS_H) \
    insn-config.h $(BASIC_BLOCK_H) $(RECOG_H) $(OBSTACK_H) $(BITMAP_H) \
-   $(EXPR_H) $(EXCEPT_H) $(REGS_H) $(TREE_PASS_H) $(DF_H) dce.h
+   $(EXPR_H) $(EXCEPT_H) $(REGS_H) $(TREE_PASS_H) $(DF_H) dce.h \
+   lower-subreg.h
 target-globals.o : target-globals.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
    $(TM_H) insn-config.h $(MACHMODE_H) $(GGC_H) toplev.h target-globals.h \
    $(FLAGS_H) $(REGS_H) $(RTL_H) reload.h expmed.h $(EXPR_H) $(OPTABS_H) \
-   $(LIBFUNCS_H) $(CFGLOOP_H) $(IRA_INT_H) builtins.h gcse.h bb-reorder.h
+   $(LIBFUNCS_H) $(CFGLOOP_H) $(IRA_INT_H) builtins.h gcse.h bb-reorder.h \
+   lower-subreg.h
 hw-doloop.o : hw-doloop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    $(RTL_H) $(FLAGS_H) $(EXPR_H) hard-reg-set.h $(BASIC_BLOCK_H) $(TM_P_H) \
    $(DF_H) $(CFGLAYOUT_H) $(CFGLOOP_H) output.h $(RECOG_H) $(TARGET_H) \

gcc/lower-subreg.h

+/* Target-dependent costs for lower-subreg.c.
+   Copyright (C) 2012 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 LOWER_SUBREG_H
+#define LOWER_SUBREG_H 1
+
+/* Information about whether, and where, lower-subreg should be applied.  */
+struct lower_subreg_choices {
+  /* A boolean vector for move splitting that is indexed by mode and is
+     true for each mode that is to have its copies split.  */
+  bool move_modes_to_split[MAX_MACHINE_MODE];
+
+  /* True if zero-extensions from word_mode to twice_word_mode should
+     be split.  */
+  bool splitting_zext;
+
+  /* Index X is true if twice_word_mode shifts by X + BITS_PER_WORD
+     should be split.  */
+  bool splitting_ashift[MAX_BITS_PER_WORD];
+  bool splitting_lshiftrt[MAX_BITS_PER_WORD];
+
+  /* True if there is at least one mode that is worth splitting.  */
+  bool something_to_do;
+};
+
+/* Target-specific information for the subreg lowering pass.  */
+struct target_lower_subreg {
+  /* An integer mode that is twice as wide as word_mode.  */
+  enum machine_mode x_twice_word_mode;
+
+  /* What we have decided to do when optimizing for size (index 0)
+     and speed (index 1).  */
+  struct lower_subreg_choices x_choices[2];
+};
+
+extern struct target_lower_subreg default_target_lower_subreg;
+#if SWITCHABLE_TARGET
+extern struct target_lower_subreg *this_target_lower_subreg;
+#else
+#define this_target_lower_subreg (&default_target_lower_subreg)
+#endif
+
+#endif

gcc/rtl.h

@@ -2526,6 +2526,9 @@ extern void init_expmed (void);
 extern void expand_inc (rtx, rtx);
 extern void expand_dec (rtx, rtx);
 
+/* In lower-subreg.c */
+extern void init_lower_subreg (void);
+
 /* In gcse.c */
 extern bool can_copy_p (enum machine_mode);
 extern bool can_assign_to_reg_without_clobbers_p (rtx);

gcc/target-globals.c

@@ -40,6 +40,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "builtins.h"
 #include "gcse.h"
 #include "bb-reorder.h"
+#include "lower-subreg.h"
 
 #if SWITCHABLE_TARGET
 struct target_globals default_target_globals = {
@@ -56,7 +57,8 @@ struct target_globals default_target_globals = {
   &default_target_ira_int,
   &default_target_builtins,
   &default_target_gcse,
-  &default_target_bb_reorder
+  &default_target_bb_reorder,
+  &default_target_lower_subreg
 };
 
 struct target_globals *
@@ -79,6 +81,7 @@ save_target_globals (void)
   g->builtins = XCNEW (struct target_builtins);
   g->gcse = XCNEW (struct target_gcse);
   g->bb_reorder = XCNEW (struct target_bb_reorder);
+  g->lower_subreg = XCNEW (struct target_lower_subreg);
   restore_target_globals (g);
   init_reg_sets ();
   target_reinit ();

gcc/target-globals.h

@@ -35,6 +35,7 @@ extern struct target_ira_int *this_target_ira_int;
 extern struct target_builtins *this_target_builtins;
 extern struct target_gcse *this_target_gcse;
 extern struct target_bb_reorder *this_target_bb_reorder;
+extern struct target_lower_subreg *this_target_lower_subreg;
 
 struct GTY(()) target_globals {
   struct target_flag_state *GTY((skip)) flag_state;
@@ -51,6 +52,7 @@ struct GTY(()) target_globals {
   struct target_builtins *GTY((skip)) builtins;
   struct target_gcse *GTY((skip)) gcse;
   struct target_bb_reorder *GTY((skip)) bb_reorder;
+  struct target_lower_subreg *GTY((skip)) lower_subreg;
 };
 
 extern struct target_globals default_target_globals;
@@ -74,6 +76,7 @@ restore_target_globals (struct target_globals *g)
   this_target_builtins = g->builtins;
   this_target_gcse = g->gcse;
   this_target_bb_reorder = g->bb_reorder;
+  this_target_lower_subreg = g->lower_subreg;
 }
 #endif
 

gcc/toplev.c

@@ -1601,6 +1601,7 @@ backend_init_target (void)
   /* rtx_cost is mode-dependent, so cached values need to be recomputed
      on a mode change.  */
   init_expmed ();
+  init_lower_subreg ();
 
   /* We may need to recompute regno_save_code[] and regno_restore_code[]
      after a mode change as well.  */