basic-block.h: Changed basic block numbering so that the entry block is 0 and the exit block is 1.

2005-12-17  Danny Berlin <dberlin@dberlin.org>
	    Kenneth Zadeck <zadeck@naturalbridge.com>

	* basic-block.h: Changed basic block numbering so that the entry
	block is 0 and the exit block is 1.  Changed insn iterators so
	that they are tolerant of blocks with no insns.
	* regrename.c (copyprop_hardreg_forward): Changed basic block
	numbering so that the entry block is 0 and the exit block is 1.
	* sched-ebb.c (sehedule_ebbs): Ditto.
	* tracer.c (branch_ratio_cutoff): Ditto.
	* cfgloopmanip.c (fix_loop_structure): Ditto.
	* cfghooks.c (verify_flow_info): Ditto.
	* cfg.c (compact_blocks): Ditto.
	* reorg.c (dbr_schedule): Ditto.
	* flow.c (calculate_global_regs_live, libcall_dead_p): Ditto.
	* dominance.c (calc_dfs_tree_nonrec, calc_dfs_tree,
	calculate_dominance_info): Ditto.
	* cfganal.c (create_edge_list, print_edge_list,
	flow_depth_first_order_compute, flow_dfs_compute_reverse_init,
	flow_dfs_compute_reverse_add_bb, flow_dfs_compute_reverse_execute,
	dfs_enumerate_from): Ditto.
	* global.c (global_alloc, set_up_bb_rts_numbers): Ditto.
	* ifcvt.c (find_if_case_2): Ditto.
	* cfgbuild.c (control_flow_insn_p, count_basic_blocks,
	find_basic_blocks): Ditto.
	* predict.c (predict_loops, tree_bb_level_predictions,
	predict_paths_leading_to, propagate_freq): Ditto.
	* lcm.c (compute_antinout_edge, compute_laterin,
	compute_available): Ditto.
	* function.c (thread_prologue_and_epilogue_insns): Ditto.
	* gcse.c (gcse_main, bypass_jumps): Ditto.
	* profile.c (compute_branch_probabilities,
	compute_value_histograms, branch_prob): Ditto.
	* tree-flow-inline.h (bsi_start, bsi_after_labels,
	bsi_last): Ditto.
	* tree-ssa-phiopt.c (tree_ssa_phiopt,
	blocks_in_phiopt_order): Ditto.
	* bt-load.c (compute_defs_uses_and_gen, compute_kill,
	compute_out, link_btr_uses, migrate_btr_defs): Ditto.
	* tree-dfa.c (collect_dfa_stats): Ditto.
	* cfgcleanup.c (try_forward_edges, try_optimize_cfg): Ditto.
	* cfglayout.c (fixup_reorder_chain): Ditto.
	* bb-reorder.c (reorder_basic_blocks, duplicate_computed_gotos,
	partition_hot_cold_basic_blocks): Ditto.
	* var-tracking.c (vt_find_locations): Ditto.
	* cfgloop.c (flow_loops_cfg_dump, flow_loops_find, get_loop_body): Ditto.
	* sched-rgn.c (compute_trg_info, init_regions, schedule_insns): Ditto.
	* tree-cfg.c (init_empty_tree_cfg, build_tree_cfg, make_edges
	label_to_block_fn, print_loop_ir, tree_flow_call_edges_add): Ditto.
	* tree-ssa-reassoc.c (init_reassoc): Ditto.
	* cfgrtl.c (entry_of_function, rtl_verify_flow_info,
	rtl_flow_call_edges_add, rtl_flow_call_edges_add): Ditto.
	* df.c (df_analyze_1, hybrid_search, iterative_dataflow): Ditto
	and removed unused reverse orders.
	* df.h (): Ditto.
	* combine.c: Fix document typo.



Co-Authored-By: Kenneth Zadeck <zadeck@naturalbridge.com>

From-SVN: r108713

1 files changed, 7 insertions, 4 deletions

diff --git a/gcc/cfgbuild.c b/gcc/cfgbuild.c
index e860e98..834119d 100644
--- a/gcc/cfgbuild.c
+++ b/gcc/cfgbuild.c
@@ -138,7 +138,7 @@ control_flow_insn_p (rtx insn)
 static int
 count_basic_blocks (rtx f)
 {
-  int count = 0;
+  int count = NUM_FIXED_BLOCKS;
   bool saw_insn = false;
   rtx insn;
 
@@ -164,10 +164,10 @@ count_basic_blocks (rtx f)
 
   /* The rest of the compiler works a bit smoother when we don't have to
      check for the edge case of do-nothing functions with no basic blocks.  */
-  if (count == 0)
+  if (count == NUM_FIXED_BLOCKS)
     {
       emit_insn (gen_rtx_USE (VOIDmode, const0_rtx));
-      count = 1;
+      count = NUM_FIXED_BLOCKS + 1;
     }
 
   return count;
@@ -529,10 +529,11 @@ find_basic_blocks (rtx f)
     }
 
   n_basic_blocks = count_basic_blocks (f);
-  last_basic_block = 0;
+  last_basic_block = NUM_FIXED_BLOCKS;
   ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
   EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
 
+
   /* Size the basic block table.  The actual structures will be allocated
      by find_basic_blocks_1, since we want to keep the structure pointers
      stable across calls to find_basic_blocks.  */
@@ -542,6 +543,8 @@ find_basic_blocks (rtx f)
      actually lay them out.  */
 
   VARRAY_BB_INIT (basic_block_info, n_basic_blocks, "basic_block_info");
+  BASIC_BLOCK (ENTRY_BLOCK) = ENTRY_BLOCK_PTR;
+  BASIC_BLOCK (EXIT_BLOCK) = EXIT_BLOCK_PTR;
 
   find_basic_blocks_1 (f);