2007-09-02 Kenneth Zadeck <zadeck@naturalbridge.com>

	* ra-conflict.c: New file.
	* ra.h: New file.
	* reload.c (push_reload, find_dummy_reload): Change DF_RA_LIVE
	usage to DF_LIVE usage.
	* rtlanal.c (subreg_nregs_with_regno): New function.  
	* df-scan.c (df_def_record_1, df_uses_record): Add code to set
	DF_REF_EXTRACT, DF_REF_STRICT_LOWER_PART, and DF_REF_SUBREG flags.
	(df_has_eh_preds): Removed.
	(df_bb_refs_collect, df_bb_refs_collect, df_bb_refs_collect,
	df_exit_block_uses_collect): Changed call from df_has_eh_preds to
	bb_has_eh_pred.
	* global.c (allocno, max_allocno, conflicts, allocno_row_words,
	reg_allocno, EXECUTE_IF_SET_IN_ALLOCNO_SET): Moved to ra.h
	(SET_ALLOCNO_LIVE, CLEAR_ALLOCNO_LIVE): Moved to ra-conflicts.c.
	(regs_set, record_one_conflict, record_conflicts, mark_reg_store,
	mark_reg_clobber, mark_reg_conflicts, mark_reg_death): Deleted.
	(global_alloc): Turn off rescanning insns after call to
	global_conflicts and added call to set_preferences.
	(global_conflicts): Moved to ra-alloc.c.
	(set_preferences_1, set_preferences): New function.
	(mirror_conflicts): Changed types for various variables.
	(mark_elimination): Change DF_RA_LIVE
	usage to DF_LIVE usage.
	(build_insn_chain): Rewritten from scratch and made local.
	(print_insn_chain, print_insn_chains): New functions.
	(dump_conflicts): Do not print conflicts for fixed_regs.
	(rest_of_handle_global_alloc): Turn off insn rescanning.
	* hard-reg-set.h: Fixed comment.
	* local-alloc.c (update_equiv_regs): Change DF_RA_LIVE
	usage to DF_LIVE usage and delete refs to TOP sets.
	(block_alloc): Mark regs as live if they are in the artificial
	defs at top of block.
	(find_stack_regs): New function.
	(rest_of_handle_local_alloc): Changed urec problem to live
	problem and do not turn off df rescanning.
	* df.h (DF_UREC, DF_UREC_BB_INFO, DF_LIVE_TOP, DF_RA_LIVE_IN,
	DF_RA_LIVE_TOP, DF_RA_LIVE_OUT, df_urec_bb_info, df_urec,
	df_urec_add_problem, df_urec_get_bb_info, df_has_eh_preds): Removed.
	(DF_CHAIN, DF_NOTE, DF_CHAIN): Renumbered.
	(DF_REF_EXTRACT, DF_REF_STRICT_LOWER_PART, DF_REF_SUBREG): New
	fields in df_ref_flags.  The rest have been renumbered.  
	* init-regs.c (initialize_uninitialized_regs): Enhanced debugging
	at -O1.
	* rtl.h (subreg_nregs_with_regno): New function.
	* df-problems.c: (df_get_live_out, df_get_live_in,
	df_get_live_top): Removed reference to DF_RA_LIVE.
	(df_lr_reset, df_lr_transfer_function, df_live_free_bb_info,
	df_live_alloc, df_live_reset, df_live_local_finalize,
	df_live_free): Make top set only if different from in set.
	(df_lr_top_dump, df_live_top_dump): Only print top set if
	different from in set.
	(df_lr_bb_local_compute): Removed unnecessary check.
	(df_urec_problem_data, df_urec_set_bb_info, df_urec_free_bb_info, 
	df_urec_alloc, df_urec_mark_reg_change, earlyclobber_regclass, 
	df_urec_check_earlyclobber, df_urec_mark_reg_use_for_earlyclobber,
	df_urec_mark_reg_use_for_earlyclobber_1, df_urec_bb_local_compute,
	df_urec_local_compute, df_urec_init, df_urec_local_finalize, 
	df_urec_confluence_n, df_urec_transfer_function, df_urec_free, 
	df_urec_top_dump, df_urec_bottom_dump, problem_UREC,
	df_urec_add_problem): Removed.
	(df_simulate_fixup_sets): Changed call from df_has_eh_preds to
	bb_has_eh_pred. 
	* Makefile.in (ra-conflict.o, ra.h): New dependencies.
	* basic_block.h (bb_has_abnormal_pred): New function.
	* reload1.c (compute_use_by_pseudos): Change DF_RA_LIVE
	usage to DF_LIVE usage.
	


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@128957 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 68 insertions, 20 deletions

diff --git a/gcc/local-alloc.c b/gcc/local-alloc.c
index dc56ca47917..4ef1f021f03 100644
--- a/gcc/local-alloc.c
+++ b/gcc/local-alloc.c
@@ -1211,13 +1211,9 @@ update_equiv_regs (void)
   if (!bitmap_empty_p (cleared_regs))
     FOR_EACH_BB (bb)
       {
-	bitmap_and_compl_into (DF_RA_LIVE_IN (bb), cleared_regs);
-	if (DF_RA_LIVE_TOP (bb))
-	  bitmap_and_compl_into (DF_RA_LIVE_TOP (bb), cleared_regs);
-	bitmap_and_compl_into (DF_RA_LIVE_OUT (bb), cleared_regs);
+	bitmap_and_compl_into (DF_LIVE_IN (bb), cleared_regs);
+	bitmap_and_compl_into (DF_LIVE_OUT (bb), cleared_regs);
 	bitmap_and_compl_into (DF_LR_IN (bb), cleared_regs);
-	if (DF_LR_TOP (bb))
-	  bitmap_and_compl_into (DF_LR_TOP (bb), cleared_regs);
 	bitmap_and_compl_into (DF_LR_OUT (bb), cleared_regs);
       }
 
@@ -1277,6 +1273,7 @@ block_alloc (int b)
   int max_uid = get_max_uid ();
   int *qty_order;
   int no_conflict_combined_regno = -1;
+  struct df_ref ** def_rec;
 
   /* Count the instructions in the basic block.  */
 
@@ -1299,7 +1296,19 @@ block_alloc (int b)
 
   /* Initialize table of hardware registers currently live.  */
 
-  REG_SET_TO_HARD_REG_SET (regs_live, DF_LR_TOP (BASIC_BLOCK (b)));
+  REG_SET_TO_HARD_REG_SET (regs_live, DF_LR_IN (BASIC_BLOCK (b)));
+
+  /* This is conservative, as this would include registers that are
+     artificial-def'ed-but-not-used.  However, artificial-defs are
+     rare, and such uninitialized use is rarer still, and the chance
+     of this having any performance impact is even less, while the
+     benefit is not having to compute and keep the TOP set around.  */
+  for (def_rec = df_get_artificial_defs (b); *def_rec; def_rec++)
+    {
+      int regno = DF_REF_REGNO (*def_rec);
+      if (regno < FIRST_PSEUDO_REGISTER)
+	SET_HARD_REG_BIT (regs_live, regno);
+    }
 
   /* This loop scans the instructions of the basic block
      and assigns quantities to registers.
@@ -2502,6 +2511,49 @@ dump_local_alloc (FILE *file)
       fprintf (file, ";; Register %d in %d.\n", i, reg_renumber[i]);
 }
 
+#ifdef STACK_REGS
+static void
+find_stack_regs (void)
+{
+  bitmap stack_regs = BITMAP_ALLOC (NULL);
+  int i;
+  HARD_REG_SET stack_hard_regs, used;
+  basic_block bb;
+  
+  /* Any register that MAY be allocated to a register stack (like the
+     387) is treated poorly.  Each such register is marked as being
+     live everywhere.  This keeps the register allocator and the
+     subsequent passes from doing anything useful with these values.
+
+     FIXME: This seems like an incredibly poor idea.  */
+
+  CLEAR_HARD_REG_SET (stack_hard_regs);
+  for (i = FIRST_STACK_REG; i <= LAST_STACK_REG; i++)
+    SET_HARD_REG_BIT (stack_hard_regs, i);
+
+  for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
+    {
+      COPY_HARD_REG_SET (used, reg_class_contents[reg_preferred_class (i)]);
+      IOR_HARD_REG_SET (used, reg_class_contents[reg_alternate_class (i)]);
+      AND_HARD_REG_SET (used, stack_hard_regs);
+      if (!hard_reg_set_empty_p (used))
+	bitmap_set_bit (stack_regs, i);
+    }
+
+  if (dump_file)
+    bitmap_print (dump_file, stack_regs, "stack regs:", "\n");
+
+  FOR_EACH_BB (bb)
+    {
+      bitmap_ior_into (DF_LIVE_IN (bb), stack_regs);
+      bitmap_and_into (DF_LIVE_IN (bb), DF_LR_IN (bb));
+      bitmap_ior_into (DF_LIVE_OUT (bb), stack_regs);
+      bitmap_and_into (DF_LIVE_OUT (bb), DF_LR_OUT (bb));
+    }
+  BITMAP_FREE (stack_regs);
+}
+#endif
+
 /* Run old register allocator.  Return TRUE if we must exit
    rest_of_compilation upon return.  */
 static unsigned int
@@ -2512,26 +2564,22 @@ rest_of_handle_local_alloc (void)
 
   df_note_add_problem ();
 
-  if (optimize > 1)
-    df_remove_problem (df_live);
-  /* Create a new version of df that has the special version of UR if
-     we are doing optimization.  */
-  if (optimize)
-    df_urec_add_problem ();
+  if (optimize == 1)
+    {
+      df_live_add_problem ();
+      df_live_set_all_dirty ();
+    }
 #ifdef ENABLE_CHECKING
   df->changeable_flags |= DF_VERIFY_SCHEDULED;
 #endif
   df_analyze ();
+#ifdef STACK_REGS
+  if (optimize)
+    find_stack_regs ();
+#endif
   regstat_init_n_sets_and_refs ();
   regstat_compute_ri ();
 
-  /* There is just too much going on in the register allocators to
-     keep things up to date.  At the end we have to rescan anyway
-     because things change when the reload_completed flag is set.  
-     So we just turn off scanning and we will rescan by hand.  */
-  df_set_flags (DF_NO_INSN_RESCAN);
-
-
   /* If we are not optimizing, then this is the only place before
      register allocation where dataflow is done.  And that is needed
      to generate these warnings.  */