PR rtl-optimization/42889

	* df.h (df_set_bb_dirty_nonlr): New prototype.
	* df-core.c (df_set_bb_dirty_nonlr): New function.
	* df-scan.c (df_insn_rescan): Call it instead of
	df_set_bb_dirty for DEBUG_INSNs.

	* gcc.dg/pr42889.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@156344 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 24 insertions, 0 deletions

diff --git a/gcc/df-core.c b/gcc/df-core.c
index 5ec802d0f8b..cee00b9dafd 100644
--- a/gcc/df-core.c
+++ b/gcc/df-core.c
@@ -1354,6 +1354,30 @@ df_set_bb_dirty (basic_block bb)
 }
 
 
+/* Mark BB as needing it's transfer functions as being out of
+   date, except for LR problem.  Used when analyzing DEBUG_INSNs,
+   as LR problem can trigger DCE, and DEBUG_INSNs shouldn't ever
+   shorten or enlarge lifetime of regs.  */
+
+void
+df_set_bb_dirty_nonlr (basic_block bb)
+{
+  if (df)
+    {
+      int p;
+      for (p = 1; p < df->num_problems_defined; p++)
+	{
+	  struct dataflow *dflow = df->problems_in_order[p];
+	  if (dflow == df_lr)
+	    continue;
+	  if (dflow->out_of_date_transfer_functions)
+	    bitmap_set_bit (dflow->out_of_date_transfer_functions, bb->index);
+	  dflow->solutions_dirty = true;
+	}
+    }
+}
+
+
 /* Clear the dirty bits.  This is called from places that delete
    blocks.  */
 static void