* emit-rtl.c (remove_unncessary_notes): Check that all

	NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes have an
	associated NOTE_BLOCK.
	* function.h (identify_blocks): Update comments.
	(reorder_blocks): Declare.
	* function.c (identify_blocks): Don't take paramters.
	(reorder_blocks): Don't take parameters.
	* loop.h (find_loop_tree_blocks): Remove.
	(unroll_block_trees): Likewise.
	* loop.c (loop_optimize): Don't call find_loop_tree_blocks.  Use
	reorder_blocks instead of unroll_block_trees.h
	* sibcall.c (optimize_sibling_and_tail_recursive_calls): Likewise.
	* stmt.c (find_loop_tree_blocks): Remove.
	(unroll_block_trees): Likewise.
	* toplev.c (rest_of_compilation): Don't call find_loop_tree_blocks
	in whole-function mode.
	* tree.h (reorder_blocks): Remove declaration.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@32632 138bc75d-0d04-0410-961f-82ee72b054a4

10 files changed, 62 insertions, 70 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1301dab8e3c..5f9babb94dd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,23 @@
 2000-03-18  Mark Mitchell  <mark@codesourcery.com>
 
+	* emit-rtl.c (remove_unncessary_notes): Check that all
+	NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes have an
+	associated NOTE_BLOCK.
+	* function.h (identify_blocks): Update comments.
+	(reorder_blocks): Declare.
+	* function.c (identify_blocks): Don't take paramters.
+	(reorder_blocks): Don't take parameters.
+	* loop.h (find_loop_tree_blocks): Remove.
+	(unroll_block_trees): Likewise.
+	* loop.c (loop_optimize): Don't call find_loop_tree_blocks.  Use
+	reorder_blocks instead of unroll_block_trees.h
+	* sibcall.c (optimize_sibling_and_tail_recursive_calls): Likewise.
+	* stmt.c (find_loop_tree_blocks): Remove.
+	(unroll_block_trees): Likewise.
+	* toplev.c (rest_of_compilation): Don't call find_loop_tree_blocks
+	in whole-function mode.
+	* tree.h (reorder_blocks): Remove declaration.
+
 	* expr.c: Include intl.h.
 	* Makefile.in (expr.o): Depend on intl.h.
 	
diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c
index 3d6f73b69ac..764a5ad7f20 100644
--- a/gcc/emit-rtl.c
+++ b/gcc/emit-rtl.c
@@ -2667,9 +2667,8 @@ remove_unncessary_notes ()
   rtx insn;
   rtx next;
 
-  /* Remove NOTE_INSN_DELETED notes.  We must not remove the first
-     instruction in the function because the compiler depends on the
-     first instruction being a note.  */
+  /* We must not remove the first instruction in the function because
+     the compiler depends on the first instruction being a note.  */
   for (insn = NEXT_INSN (get_insns ()); insn; insn = next)
     {
       /* Remember what's next.  */
@@ -2679,6 +2678,14 @@ remove_unncessary_notes ()
       if (GET_CODE (insn) != NOTE)
 	continue;
 
+      /* By now, all notes indicating lexical blocks should have
+	 NOTE_BLOCK filled in.  */
+      if ((NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
+	   || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
+	  && NOTE_BLOCK (insn) == NULL_TREE)
+	abort ();
+
+      /* Remove NOTE_INSN_DELETED notes.  */
       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED)
 	remove_insn (insn);
       else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
diff --git a/gcc/function.c b/gcc/function.c
index dfd87618396..e994558fdc8 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -5508,11 +5508,6 @@ round_trampoline_addr (tramp)
   return tramp;
 }
 
-/* The functions identify_blocks and reorder_blocks provide a way to
-   reorder the tree of BLOCK nodes, for optimizers that reshuffle or
-   duplicate portions of the RTL code.  Call identify_blocks before
-   changing the RTL, and call reorder_blocks after.  */
-
 /* Put all this function's BLOCK nodes including those that are chained
    onto the first block into a vector, and return it.
    Also store in each NOTE for the beginning or end of a block
@@ -5521,13 +5516,12 @@ round_trampoline_addr (tramp)
    and INSNS, the insn chain of the function.  */
 
 void
-identify_blocks (block, insns)
-     tree block;
-     rtx insns;
+identify_blocks ()
 {
   int n_blocks;
   tree *block_vector, *last_block_vector;
   tree *block_stack;
+  tree block = DECL_INITIAL (current_function_decl);
 
   if (block == 0)
     return;
@@ -5537,8 +5531,10 @@ identify_blocks (block, insns)
   block_vector = get_block_vector (block, &n_blocks);
   block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
 
-  last_block_vector = identify_blocks_1 (insns, block_vector + 1,
-					 block_vector + n_blocks, block_stack);
+  last_block_vector = identify_blocks_1 (get_insns (), 
+					 block_vector + 1,
+					 block_vector + n_blocks, 
+					 block_stack);
 
   /* If we didn't use all of the subblocks, we've misplaced block notes.  */
   /* ??? This appears to happen all the time.  Latent bugs elsewhere?  */
@@ -5616,36 +5612,30 @@ identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
   return block_vector;
 }
 
-/* Given a revised instruction chain, rebuild the tree structure of
-   BLOCK nodes to correspond to the new order of RTL.  The new block
-   tree is inserted below TOP_BLOCK.  Returns the current top-level
-   block.  */
+/* Identify BLOCKs referenced by more than one
+   NOTE_INSN_BLOCK_{BEG,END}, and create duplicate blocks. */
 
-tree
-reorder_blocks (block, insns)
-     tree block;
-     rtx insns;
+void
+reorder_blocks ()
 {
-  tree current_block = block;
+  tree block = DECL_INITIAL (current_function_decl);
   varray_type block_stack;
 
   if (block == NULL_TREE)
-    return NULL_TREE;
+    return;
 
   VARRAY_TREE_INIT (block_stack, 10, "block_stack");
 
-  /* Prune the old trees away, so that it doesn't get in the way.  */
-  BLOCK_SUBBLOCKS (current_block) = 0;
-  BLOCK_CHAIN (current_block) = 0;
+  /* Prune the old trees away, so that they don't get in the way.  */
+  BLOCK_SUBBLOCKS (block) = NULL_TREE;
+  BLOCK_CHAIN (block) = NULL_TREE;
 
-  reorder_blocks_1 (insns, current_block, &block_stack);
+  reorder_blocks_1 (get_insns (), block, &block_stack);
 
-  BLOCK_SUBBLOCKS (current_block)
-    = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
+  BLOCK_SUBBLOCKS (block)
+    = blocks_nreverse (BLOCK_SUBBLOCKS (block));
 
   VARRAY_FREE (block_stack);
-
-  return current_block;
 }
 
 /* Helper function for reorder_blocks.  Process the insn chain beginning
diff --git a/gcc/function.h b/gcc/function.h
index 8b26ec2e371..5c7aa414d30 100644
--- a/gcc/function.h
+++ b/gcc/function.h
@@ -303,7 +303,7 @@ struct function
 
   /* Nonzero if this function is being processed in function-at-a-time
      mode.  In other words, if all tree structure for this function,
-     including the BLOCK tree is created, before RTL generation
+     including the BLOCK tree, is created before RTL generation
      commences.  */
   int x_whole_function_mode_p;
 
@@ -548,10 +548,12 @@ struct function *find_function_data PARAMS ((tree));
 /* Pointer to chain of `struct function' for containing functions.  */
 extern struct function *outer_function_chain;
 
-/* Put all this function's BLOCK nodes into a vector and return it.
-   Also store in each NOTE for the beginning or end of a block
-   the index of that block in the vector.  */
-extern void identify_blocks PARAMS ((tree, rtx));
+/* Set NOTE_BLOCK for each block note in the current function.  */
+extern void identify_blocks PARAMS ((void));
+
+/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
+   and create duplicate blocks.  */
+extern void reorder_blocks PARAMS ((void));
 
 /* Set BLOCK_NUMBER for all the blocks in FN.  */
 extern void number_blocks PARAMS ((tree));
diff --git a/gcc/loop.c b/gcc/loop.c
index f7a12ded4cc..74ff0a6a7fd 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -518,14 +518,6 @@ loop_optimize (f, dumpfile, unroll_p, bct_p)
     if (uid_luid[i] == 0)
       uid_luid[i] = uid_luid[i - 1];
 
-  /* If debugging and unrolling loops, we must replicate the tree
-     nodes corresponding to the BLOCKs inside the loop, so that the
-     original one to one mapping will remain.  We sometimes unroll
-     loops even when unroll_p is false, so we must always do this when
-     debugging.  */
-  if (write_symbols != NO_DEBUG)
-    find_loop_tree_blocks ();
-
   /* Determine if the function has indirect jump.  On some systems
      this prevents low overhead loop instructions from being used.  */
   indirect_jump_in_function = indirect_jump_in_function_p (f);
@@ -540,9 +532,12 @@ loop_optimize (f, dumpfile, unroll_p, bct_p)
 	scan_loop (loop, unroll_p, bct_p);
     }
 
-  /* Replicate the BLOCKs.  */
+  /* If there were lexical blocks inside the loop, they have been
+     replicated.  We will now have more than one NOTE_INSN_BLOCK_BEG
+     and NOTE_INSN_BLOCK_END for each such block.  We must duplicate
+     the BLOCKs as well.  */
   if (write_symbols != NO_DEBUG)
-    unroll_block_trees ();
+    reorder_blocks ();
 
   end_alias_analysis ();
 
diff --git a/gcc/loop.h b/gcc/loop.h
index 8fbde2146ac..f7769f8ea4a 100644
--- a/gcc/loop.h
+++ b/gcc/loop.h
@@ -248,6 +248,3 @@ int back_branch_in_range_p PARAMS ((const struct loop *, rtx));
 
 int loop_insn_first_p PARAMS ((rtx, rtx));
 
-/* Forward declarations for non-static functions declared in stmt.c.  */
-void find_loop_tree_blocks PARAMS ((void));
-void unroll_block_trees PARAMS ((void));
diff --git a/gcc/sibcall.c b/gcc/sibcall.c
index b399137a0bf..bbb70243e72 100644
--- a/gcc/sibcall.c
+++ b/gcc/sibcall.c
@@ -571,7 +571,7 @@ success:
      CALL_PLACEHOLDER alternatives that we didn't emit.  Rebuild the
      lexical block tree to correspond to the notes that still exist.  */
   if (replaced_call_placeholder)
-    unroll_block_trees ();
+    reorder_blocks ();
 
   /* This information will be invalid after inline expansion.  Kill it now.  */
   free_basic_block_vars (0);
diff --git a/gcc/stmt.c b/gcc/stmt.c
index e919cd2c152..837df5cb670 100644
--- a/gcc/stmt.c
+++ b/gcc/stmt.c
@@ -6372,19 +6372,3 @@ emit_case_nodes (index, node, default_label, index_type)
     }
 }
 
-/* These routines are used by the loop unrolling code.  They copy BLOCK trees
-   so that the debugging info will be correct for the unrolled loop.  */
-
-void
-find_loop_tree_blocks ()
-{
-  identify_blocks (DECL_INITIAL (current_function_decl), get_insns ());
-}
-
-void
-unroll_block_trees ()
-{
-  tree block = DECL_INITIAL (current_function_decl);
-
-  reorder_blocks (block, get_insns ());
-}
diff --git a/gcc/toplev.c b/gcc/toplev.c
index 1e1a650139c..f304144b3c8 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -2858,7 +2858,8 @@ rest_of_compilation (decl)
 
   /* First, make sure that NOTE_BLOCK is set correctly for each
      NOTE_INSN_BLOCK_BEG/NOTE_INSN_BLOCK_END note.  */
-  find_loop_tree_blocks ();
+  if (!cfun->x_whole_function_mode_p)
+    identify_blocks ();
 
   /* Then remove any notes we don't need.  That will make iterating
      over the instruction sequence faster, and allow the garbage
@@ -2868,7 +2869,7 @@ rest_of_compilation (decl)
   /* In function-at-a-time mode, we do not attempt to keep the BLOCK
      tree in sensible shape.  So, we just recalculate it here.  */
   if (cfun->x_whole_function_mode_p)
-    unroll_block_trees ();
+    reorder_blocks ();
 
   /* If we are reconsidering an inline function
      at the end of compilation, skip the stuff for making it inline.  */
diff --git a/gcc/tree.h b/gcc/tree.h
index 9076d5ec39f..1c5cebc3cf3 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -2524,8 +2524,6 @@ extern void push_temp_slots		PARAMS ((void));
 extern void preserve_temp_slots		PARAMS ((struct rtx_def *));
 extern void preserve_rtl_expr_temps	PARAMS ((tree));
 extern int aggregate_value_p		PARAMS ((tree));
-extern tree reorder_blocks		PARAMS ((tree,
-						struct rtx_def *));
 extern void free_temps_for_rtl_expr	PARAMS ((tree));
 extern void instantiate_virtual_regs	PARAMS ((tree, struct rtx_def *));
 extern void unshare_all_rtl		PARAMS ((tree, struct rtx_def *));