PR rtl-optimization/32300

	* see.c (see_copy_insn): New function.
	(see_def_extension_not_merged, see_merge_one_use_extension,
	see_merge_one_def_extension): Use it.  Avoid changing
	PREV_INSN/NEXT_INSN chains directly, insted emit insns
	into sequences.  Call df_insn_delete on temporary insns
	that won't be emitted into the insn stream.
	(rest_of_handle_see): Turn off DF_DEFER_INSN_RESCAN
	and run df_process_deferred_rescans () before run_fast_dce.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@128108 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 117 insertions, 65 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7f83513aeb5..251141d14fb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -3,6 +3,16 @@
 	* config/rs6000/tramp.asm: Include config.h.
 	Check __PIC__ or __pic__ macro instead of SHARED.
 
+	PR rtl-optimization/32300
+	* see.c (see_copy_insn): New function.
+	(see_def_extension_not_merged, see_merge_one_use_extension,
+	see_merge_one_def_extension): Use it.  Avoid changing
+	PREV_INSN/NEXT_INSN chains directly, insted emit insns
+	into sequences.  Call df_insn_delete on temporary insns
+	that won't be emitted into the insn stream.
+	(rest_of_handle_see): Turn off DF_DEFER_INSN_RESCAN
+	and run df_process_deferred_rescans () before run_fast_dce.
+
 	PR tree-optimization/33017
 	* tree-data-ref.c (split_constant_offset) <case SSA_NAME>: Don't
 	recurse for pure or const function calls.
diff --git a/gcc/see.c b/gcc/see.c
index 0aba8df7132..7a351613b13 100644
--- a/gcc/see.c
+++ b/gcc/see.c
@@ -2412,6 +2412,38 @@ see_replace_src (rtx *x, void *data)
 }
 
 
+static rtx
+see_copy_insn (rtx insn)
+{
+  rtx pat = copy_insn (PATTERN (insn)), ret;
+
+  if (NONJUMP_INSN_P (insn))
+    ret = make_insn_raw (pat);
+  else if (JUMP_P (insn))
+    ret = make_jump_insn_raw (pat);
+  else if (CALL_P (insn))
+    {
+      start_sequence ();
+      ret = emit_call_insn (pat);
+      end_sequence ();
+      if (CALL_INSN_FUNCTION_USAGE (insn))
+	CALL_INSN_FUNCTION_USAGE (ret)
+	  = copy_rtx (CALL_INSN_FUNCTION_USAGE (insn));
+      SIBLING_CALL_P (ret) = SIBLING_CALL_P (insn);
+      CONST_OR_PURE_CALL_P (ret) = CONST_OR_PURE_CALL_P (insn);
+    }
+  else
+    gcc_unreachable ();
+  if (REG_NOTES (insn))
+    REG_NOTES (ret) = copy_rtx (REG_NOTES (insn));
+  INSN_LOCATOR (ret) = INSN_LOCATOR (insn);
+  RTX_FRAME_RELATED_P (ret) = RTX_FRAME_RELATED_P (insn);
+  PREV_INSN (ret) = NULL_RTX;
+  NEXT_INSN (ret) = NULL_RTX;
+  return ret;
+}
+
+
 /* At this point the pattern is expected to be:
 
    ref:	    set (dest_reg) (rhs)
@@ -2443,14 +2475,13 @@ see_def_extension_not_merged (struct see_ref_s *curr_ref_s, rtx def_se)
   struct see_replace_data d;
   /* If the original insn was already merged with an extension before,
      take the merged one.  */
-  rtx ref = (curr_ref_s->merged_insn) ? curr_ref_s->merged_insn :
-					curr_ref_s->insn;
-  rtx merged_ref_next = (curr_ref_s->merged_insn) ?
-  			NEXT_INSN (curr_ref_s->merged_insn): NULL_RTX;
-  rtx ref_copy = copy_rtx (ref);
+  rtx ref = curr_ref_s->merged_insn
+	    ? curr_ref_s->merged_insn : curr_ref_s->insn;
+  rtx merged_ref_next = curr_ref_s->merged_insn
+			? NEXT_INSN (curr_ref_s->merged_insn) : NULL_RTX;
+  rtx ref_copy = see_copy_insn (ref);
   rtx source_extension_reg = see_get_extension_reg (def_se, 0);
   rtx dest_extension_reg = see_get_extension_reg (def_se, 1);
-  rtx move_insn = NULL;
   rtx set, rhs;
   rtx dest_reg, dest_real_reg;
   rtx new_pseudo_reg, subreg;
@@ -2489,25 +2520,22 @@ see_def_extension_not_merged (struct see_ref_s *curr_ref_s, rtx def_se)
       || insn_invalid_p (ref_copy))
     {
       /* The manipulation failed.  */
+      df_insn_delete (NULL, INSN_UID (ref_copy));
 
       /* Create a new copy.  */
-      ref_copy = copy_rtx (ref);
+      ref_copy = see_copy_insn (ref);
+
+      if (curr_ref_s->merged_insn)
+        df_insn_delete (NULL, INSN_UID (curr_ref_s->merged_insn));
 
       /* Create a simple move instruction that will replace the def_se.  */
       start_sequence ();
+      emit_insn (ref_copy);
       emit_move_insn (subreg, dest_reg);
-      move_insn = get_insns ();
-      end_sequence ();
-
-      /* Link the manipulated instruction to the newly created move instruction
-	 and to the former created move instructions.  */
-      PREV_INSN (ref_copy) = NULL_RTX;
-      NEXT_INSN (ref_copy) = move_insn;
-      PREV_INSN (move_insn) = ref_copy;
-      NEXT_INSN (move_insn) = merged_ref_next;
       if (merged_ref_next != NULL_RTX)
-	PREV_INSN (merged_ref_next) = move_insn;
-      curr_ref_s->merged_insn = ref_copy;
+	emit_insn (merged_ref_next);
+      curr_ref_s->merged_insn = get_insns ();
+      end_sequence ();
 
       if (dump_file)
 	{
@@ -2516,7 +2544,7 @@ see_def_extension_not_merged (struct see_ref_s *curr_ref_s, rtx def_se)
 	  fprintf (dump_file, "Original ref:\n");
 	  print_rtl_single (dump_file, ref);
 	  fprintf (dump_file, "Move insn that was added:\n");
-	  print_rtl_single (dump_file, move_insn);
+	  print_rtl_single (dump_file, NEXT_INSN (curr_ref_s->merged_insn));
 	}
       return;
     }
@@ -2526,21 +2554,17 @@ see_def_extension_not_merged (struct see_ref_s *curr_ref_s, rtx def_se)
   /* Try to simplify the new manipulated insn.  */
   validate_simplify_insn (ref_copy);
 
+  if (curr_ref_s->merged_insn)
+    df_insn_delete (NULL, INSN_UID (curr_ref_s->merged_insn));
+
   /* Create a simple move instruction to assure the correctness of the code.  */
   start_sequence ();
+  emit_insn (ref_copy);
   emit_move_insn (dest_reg, subreg);
-  move_insn = get_insns ();
-  end_sequence ();
-
-  /* Link the manipulated instruction to the newly created move instruction and
-     to the former created move instructions.  */
-  PREV_INSN (ref_copy) = NULL_RTX;
-  NEXT_INSN (ref_copy) = move_insn;
-  PREV_INSN (move_insn) = ref_copy;
-  NEXT_INSN (move_insn) = merged_ref_next;
   if (merged_ref_next != NULL_RTX)
-    PREV_INSN (merged_ref_next) = move_insn;
-  curr_ref_s->merged_insn = ref_copy;
+    emit_insn (merged_ref_next);
+  curr_ref_s->merged_insn = get_insns ();
+  end_sequence ();
 
   if (dump_file)
     {
@@ -2548,9 +2572,9 @@ see_def_extension_not_merged (struct see_ref_s *curr_ref_s, rtx def_se)
       fprintf (dump_file, "Original ref:\n");
       print_rtl_single (dump_file, ref);
       fprintf (dump_file, "Transformed ref:\n");
-      print_rtl_single (dump_file, ref_copy);
+      print_rtl_single (dump_file, curr_ref_s->merged_insn);
       fprintf (dump_file, "Move insn that was added:\n");
-      print_rtl_single (dump_file, move_insn);
+      print_rtl_single (dump_file, NEXT_INSN (curr_ref_s->merged_insn));
     }
 }
 
@@ -2582,11 +2606,11 @@ see_merge_one_use_extension (void **slot, void *b)
 {
   struct see_ref_s *curr_ref_s = (struct see_ref_s *) b;
   rtx use_se = *slot;
-  rtx ref = (curr_ref_s->merged_insn) ? curr_ref_s->merged_insn :
-					curr_ref_s->insn;
-  rtx merged_ref_next = (curr_ref_s->merged_insn) ?
-  			NEXT_INSN (curr_ref_s->merged_insn): NULL_RTX;
-  rtx ref_copy = copy_rtx (ref);
+  rtx ref = curr_ref_s->merged_insn
+	    ? curr_ref_s->merged_insn : curr_ref_s->insn;
+  rtx merged_ref_next = curr_ref_s->merged_insn
+			? NEXT_INSN (curr_ref_s->merged_insn) : NULL_RTX;
+  rtx ref_copy = see_copy_insn (ref);
   rtx extension_set = single_set (use_se);
   rtx extension_rhs = NULL;
   rtx dest_extension_reg = see_get_extension_reg (use_se, 1);
@@ -2626,6 +2650,7 @@ see_merge_one_use_extension (void **slot, void *b)
 	  print_rtl_single (dump_file, use_se);
 	  print_rtl_single (dump_file, ref);
 	}
+      df_insn_delete (NULL, INSN_UID (ref_copy));
       /* Don't remove the current use_se from the use_se_hash and continue to
 	 the next extension.  */
       return 1;
@@ -2644,11 +2669,20 @@ see_merge_one_use_extension (void **slot, void *b)
 	  print_rtl_single (dump_file, ref);
 	}
       htab_clear_slot (curr_ref_s->use_se_hash, (PTR *)slot);
-      PREV_INSN (ref_copy) = NULL_RTX;
-      NEXT_INSN (ref_copy) = merged_ref_next;
+
+      if (curr_ref_s->merged_insn)
+	df_insn_delete (NULL, INSN_UID (curr_ref_s->merged_insn));
+
       if (merged_ref_next != NULL_RTX)
-	PREV_INSN (merged_ref_next) = ref_copy;
-      curr_ref_s->merged_insn = ref_copy;
+	{
+	  start_sequence ();
+	  emit_insn (ref_copy);
+	  emit_insn (merged_ref_next);
+	  curr_ref_s->merged_insn = get_insns ();
+	  end_sequence ();
+	}
+      else
+	curr_ref_s->merged_insn = ref_copy;
       return 1;
     }
 
@@ -2662,6 +2696,7 @@ see_merge_one_use_extension (void **slot, void *b)
 	  print_rtl_single (dump_file, use_se);
 	  print_rtl_single (dump_file, ref);
 	}
+      df_insn_delete (NULL, INSN_UID (ref_copy));
       /* Don't remove the current use_se from the use_se_hash and continue to
 	 the next extension.  */
       return 1;
@@ -2672,11 +2707,19 @@ see_merge_one_use_extension (void **slot, void *b)
   /* Try to simplify the new merged insn.  */
   validate_simplify_insn (ref_copy);
 
-  PREV_INSN (ref_copy) = NULL_RTX;
-  NEXT_INSN (ref_copy) = merged_ref_next;
+  if (curr_ref_s->merged_insn)
+    df_insn_delete (NULL, INSN_UID (curr_ref_s->merged_insn));
+
   if (merged_ref_next != NULL_RTX)
-    PREV_INSN (merged_ref_next) = ref_copy;
-  curr_ref_s->merged_insn = ref_copy;
+    {
+      start_sequence ();
+      emit_insn (ref_copy);
+      emit_insn (merged_ref_next);
+      curr_ref_s->merged_insn = get_insns ();
+      end_sequence ();
+    }
+  else
+    curr_ref_s->merged_insn = ref_copy;
 
   if (dump_file)
     {
@@ -2685,7 +2728,7 @@ see_merge_one_use_extension (void **slot, void *b)
       print_rtl_single (dump_file, use_se);
       print_rtl_single (dump_file, ref);
       fprintf (dump_file, "Merged instruction:\n");
-      print_rtl_single (dump_file, ref_copy);
+      print_rtl_single (dump_file, curr_ref_s->merged_insn);
     }
 
   /* Remove the current use_se from the use_se_hash.  This will prevent it from
@@ -2726,15 +2769,15 @@ see_merge_one_def_extension (void **slot, void *b)
   rtx def_se = *slot;
   /* If the original insn was already merged with an extension before,
      take the merged one.  */
-  rtx ref = (curr_ref_s->merged_insn) ? curr_ref_s->merged_insn :
-					curr_ref_s->insn;
-  rtx merged_ref_next = (curr_ref_s->merged_insn) ?
-  			NEXT_INSN (curr_ref_s->merged_insn): NULL_RTX;
-  rtx ref_copy = copy_rtx (ref);
+  rtx ref = curr_ref_s->merged_insn
+	    ? curr_ref_s->merged_insn : curr_ref_s->insn;
+  rtx merged_ref_next = curr_ref_s->merged_insn
+			? NEXT_INSN (curr_ref_s->merged_insn) : NULL_RTX;
+  rtx ref_copy = see_copy_insn (ref);
   rtx new_set = NULL;
   rtx source_extension_reg = see_get_extension_reg (def_se, 0);
   rtx dest_extension_reg = see_get_extension_reg (def_se, 1);
-  rtx move_insn, *rtx_slot, subreg;
+  rtx *rtx_slot, subreg;
   rtx temp_extension = NULL;
   rtx simplified_temp_extension = NULL;
   rtx *pat;
@@ -2763,6 +2806,7 @@ see_merge_one_def_extension (void **slot, void *b)
 	  print_rtl_single (dump_file, def_se);
 	}
 
+      df_insn_delete (NULL, INSN_UID (ref_copy));
       see_def_extension_not_merged (curr_ref_s, def_se);
       /* Continue to the next extension.  */
       return 1;
@@ -2851,29 +2895,25 @@ see_merge_one_def_extension (void **slot, void *b)
 	  print_rtl_single (dump_file, def_se);
 	}
 
+      df_insn_delete (NULL, INSN_UID (ref_copy));
       see_def_extension_not_merged (curr_ref_s, def_se);
       /* Continue to the next extension.  */
       return 1;
     }
 
   /* The merge succeeded!  */
+  if (curr_ref_s->merged_insn)
+    df_insn_delete (NULL, INSN_UID (curr_ref_s->merged_insn));
 
   /* Create a simple move instruction to assure the correctness of the code.  */
   subreg = gen_lowpart_SUBREG (source_extension_mode, dest_extension_reg);
   start_sequence ();
+  emit_insn (ref_copy);
   emit_move_insn (source_extension_reg, subreg);
-  move_insn = get_insns ();
-  end_sequence ();
-
-  /* Link the merged instruction to the newly created move instruction and
-     to the former created move instructions.  */
-  PREV_INSN (ref_copy) = NULL_RTX;
-  NEXT_INSN (ref_copy) = move_insn;
-  PREV_INSN (move_insn) = ref_copy;
-  NEXT_INSN (move_insn) = merged_ref_next;
   if (merged_ref_next != NULL_RTX)
-    PREV_INSN (merged_ref_next) = move_insn;
-  curr_ref_s->merged_insn = ref_copy;
+    emit_insn (merged_ref_next);
+  curr_ref_s->merged_insn = get_insns ();
+  end_sequence ();
 
   if (dump_file)
     {
@@ -2882,9 +2922,9 @@ see_merge_one_def_extension (void **slot, void *b)
       print_rtl_single (dump_file, ref);
       print_rtl_single (dump_file, def_se);
       fprintf (dump_file, "Merged instruction:\n");
-      print_rtl_single (dump_file, ref_copy);
+      print_rtl_single (dump_file, curr_ref_s->merged_insn);
       fprintf (dump_file, "Move instruction that was added:\n");
-      print_rtl_single (dump_file, move_insn);
+      print_rtl_single (dump_file, NEXT_INSN (curr_ref_s->merged_insn));
     }
 
   /* Remove the current def_se from the unmerged_def_se_hash and insert it to
@@ -3814,6 +3854,8 @@ static unsigned int
 rest_of_handle_see (void)
 {
   see_main ();
+  df_clear_flags (DF_DEFER_INSN_RESCAN);
+  df_process_deferred_rescans ();
   run_fast_dce ();
   return 0;
 }