Makefile.in (OBJS): Added dce.o.

	* Makefile.in (OBJS): Added dce.o.
	(ssa.o): Updated target to include ssa.h.
	(flow.o): Likewise.
	(toplev.o): Likewise.
	(dce.o): Created target.
	* basic-block.h: Added comments.
	(INVALID_BLOCK): Added definition.
	(connect_infinite_loops_to_exit): Added declaration.
	Moved SSA declarations to ssa.h.
	* flow.c: Added inclusion of ssa.h.
	(struct depth_first_search_dsS, depth_first_search_ds):
	Added definitions.
	(compute_immediate_postdominators): Added definition.
	(connect_infinite_loops_to_exit): Likewise.
	(flow_dfs_compute_reverse_init): Likewise.
	(flow_dfs_compute_reverse_add_bb): Likewise.
	(flow_dfs_compute_reverse_execute): Likewise.
	(flow_dfs_compute_reverse_finish): Likewise.
	* rtl.h (rtx/in_struct): Added use to determine insn necessity.
	(LABEL_P): Added definition.
	(JUMP_P): Likewise.
	(NOTE_P): Likewise.
	(BARRIER_P): Likewise.
	(JUMP_TABLE_DATA_P): Likewise.
	(INSN_DEAD_CODE_P): Likewise.
	* ssa.c: Replaced inclusions with ssa.h inclusion.
	(CONVERT_HARD_REGISTER_TO_SSA_P): Moved to ssa.h.
	(rename_registers): Removed unnecessary variables.
	* ssa.h: Created by moving declarations from ssa.c and
	basic-block.h.
	* timevar.def: Defined TV_DEAD_CODE_ELIM.
	* toplev.c: Added ssa.h inclusion.
	(dump_file_index): Added DFI_dce.
	(dump_file): Added "dce" entry.
	Defined flag_ssa.
	(f_options): Added dce entry.
	* invoke.texi: Document -fdce.  Emphasize experimental status of
	-fssa.

Co-Authored-By: Mark Mitchell <mark@codesourcery.com>

From-SVN: r35419

1 files changed, 16 insertions, 9 deletions

diff --git a/gcc/basic-block.h b/gcc/basic-block.h
index 2e54075..a018f23 100644
--- a/gcc/basic-block.h
+++ b/gcc/basic-block.h
@@ -141,6 +141,18 @@ typedef struct edge_def {
 #define EDGE_COMPLEX	(EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
 
 
+/* Basic blocks need not start with a label nor end with a jump insn.
+   For example, a previous basic block may just "conditionally fall"
+   into the succeeding basic block, and the last basic block need not
+   end with a jump insn.  Block 0 is a descendant of the entry block.
+
+   A basic block beginning with two labels cannot have notes between
+   the labels.
+
+   Data for jump tables are stored in jump_insns that occur in no
+   basic block even though these insns can follow or precede insns in
+   basic blocks.  */
+
 /* Basic block information indexed by block number.  */
 typedef struct basic_block_def {
   /* The first and last insns of the block.  */
@@ -210,6 +222,9 @@ extern regset regs_live_at_setjmp;
 #define ENTRY_BLOCK (-1)
 #define EXIT_BLOCK (-2)
 
+/* Special block number not valid for any block. */
+#define INVALID_BLOCK (-3)
+
 /* Similarly, block pointers for the edge list.  */
 extern struct basic_block_def entry_exit_blocks[2];
 #define ENTRY_BLOCK_PTR	(&entry_exit_blocks[0])
@@ -230,6 +245,7 @@ extern void insert_insn_on_edge		PARAMS ((rtx, edge));
 extern void commit_edge_insertions	PARAMS ((void));
 extern void remove_fake_edges		PARAMS ((void));
 extern void add_noreturn_fake_exit_edges	PARAMS ((void));
+extern void connect_infinite_loops_to_exit	PARAMS ((void));
 extern rtx flow_delete_insn		PARAMS ((rtx));
 extern void flow_delete_insn_chain	PARAMS ((rtx, rtx));
 extern void make_edge			PARAMS ((sbitmap *, basic_block,
@@ -514,13 +530,4 @@ extern conflict_graph conflict_graph_compute
                                         PARAMS ((regset,
 						 partition));
 
-/* In ssa.c */
-extern void convert_to_ssa		PARAMS ((void));
-extern void convert_from_ssa		PARAMS ((void));
-typedef int (*successor_phi_fn)         PARAMS ((rtx, int, int, void *));
-extern int for_each_successor_phi       PARAMS ((basic_block bb,
-						 successor_phi_fn,
-						 void *));
-extern int in_ssa_form;
-
 #endif /* _BASIC_BLOCK_H */