PR opt/10056

	* cfglayout.c (fixup_reorder_chain):  Fix dealing with the conditional
	jump jumping to the next instruction.
	* cfgrtl.c (force_nonfallthru_and_redirect):  Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@64854 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 30 insertions, 2 deletions

diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c
index 01b7e92c2cb..5e47236b4ce 100644
--- a/gcc/cfgrtl.c
+++ b/gcc/cfgrtl.c
@@ -78,7 +78,7 @@ static void commit_one_edge_insertion	PARAMS ((edge, int));
 static bool try_redirect_by_replacing_jump PARAMS ((edge, basic_block));
 static rtx last_loop_beg_note		PARAMS ((rtx));
 static bool back_edge_of_syntactic_loop_p PARAMS ((basic_block, basic_block));
-static basic_block force_nonfallthru_and_redirect PARAMS ((edge, basic_block));
+basic_block force_nonfallthru_and_redirect PARAMS ((edge, basic_block));
 
 /* Return true if NOTE is not one of the ones that must be kept paired,
    so that we may simply delete it.  */
@@ -930,7 +930,7 @@ redirect_edge_and_branch (e, target)
 /* Like force_nonfallthru below, but additionally performs redirection
    Used by redirect_edge_and_branch_force.  */
 
-static basic_block
+basic_block
 force_nonfallthru_and_redirect (e, target)
      edge e;
      basic_block target;
@@ -940,6 +940,34 @@ force_nonfallthru_and_redirect (e, target)
   edge new_edge;
   int abnormal_edge_flags = 0;
 
+  /* In the case the last instruction is conditional jump to the next
+     instruction, first redirect the jump itself and then continue
+     by creating an basic block afterwards to redirect fallthru edge.  */
+  if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR
+      && any_condjump_p (e->src->end)
+      && JUMP_LABEL (e->src->end) == e->dest->head)
+    {
+      rtx note;
+      edge b = make_edge (e->src, target, 0);
+
+      if (!redirect_jump (e->src->end, block_label (target), 0))
+	abort ();
+      note = find_reg_note (e->src->end, REG_BR_PROB, NULL_RTX);
+      if (note)
+	{
+	  int prob = INTVAL (XEXP (note, 0));
+
+	  b->probability = prob;
+	  b->count = e->count * prob / REG_BR_PROB_BASE;
+	  e->probability -= e->probability;
+	  e->count -= b->count;
+	  if (e->probability < 0)
+	    e->probability = 0;
+	  if (e->count < 0)
+	    e->count = 0;
+	}
+    }
+
   if (e->flags & EDGE_ABNORMAL)
     {
       /* Irritating special case - fallthru edge to the same block as abnormal