[RTL-ifcvt] PR rtl-optimization/68506: Fix emitting order of insns in IF-THEN-JOIN case

	PR rtl-optimization/68506
	* ifcvt.c (noce_try_cmove_arith): Try emitting the else basic block
	first if emit_a exists or then_bb modifies 'b'.  Reindent if-else
	blocks.

	* gcc.c-torture/execute/pr68506.c: New test.

From-SVN: r231003

1 files changed, 29 insertions, 31 deletions

diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c
index fc724bc..8ece873 100644
--- a/gcc/ifcvt.c
+++ b/gcc/ifcvt.c
@@ -2190,40 +2190,38 @@ noce_try_cmove_arith (struct noce_if_info *if_info)
 	  }
 
     }
-    if (emit_a && modified_in_a)
-      {
-	modified_in_b = emit_b != NULL_RTX && modified_in_p (orig_a, emit_b);
-	if (tmp_b && else_bb)
-	  {
-	    FOR_BB_INSNS (else_bb, tmp_insn)
-	    /* Don't check inside insn_b.  We will have changed it to emit_b
-	       with a destination that doesn't conflict.  */
-	      if (!(insn_b && tmp_insn == insn_b)
-		  && modified_in_p (orig_a, tmp_insn))
-		{
-		  modified_in_b = true;
-		  break;
-		}
-
-	  }
-	if (modified_in_b)
-	  goto end_seq_and_fail;
-
-	if (!noce_emit_bb (emit_b, else_bb, b_simple))
-	  goto end_seq_and_fail;
+  if (emit_a || modified_in_a)
+    {
+      modified_in_b = emit_b != NULL_RTX && modified_in_p (orig_a, emit_b);
+      if (tmp_b && else_bb)
+	{
+	  FOR_BB_INSNS (else_bb, tmp_insn)
+	  /* Don't check inside insn_b.  We will have changed it to emit_b
+	     with a destination that doesn't conflict.  */
+	  if (!(insn_b && tmp_insn == insn_b)
+	      && modified_in_p (orig_a, tmp_insn))
+	    {
+	      modified_in_b = true;
+	      break;
+	    }
+	}
+      if (modified_in_b)
+	goto end_seq_and_fail;
 
-	if (!noce_emit_bb (emit_a, then_bb, a_simple))
-	  goto end_seq_and_fail;
-      }
-    else
-      {
-	if (!noce_emit_bb (emit_a, then_bb, a_simple))
-	  goto end_seq_and_fail;
+      if (!noce_emit_bb (emit_b, else_bb, b_simple))
+	goto end_seq_and_fail;
 
-	if (!noce_emit_bb (emit_b, else_bb, b_simple))
-	  goto end_seq_and_fail;
+      if (!noce_emit_bb (emit_a, then_bb, a_simple))
+	goto end_seq_and_fail;
+    }
+  else
+    {
+      if (!noce_emit_bb (emit_a, then_bb, a_simple))
+	goto end_seq_and_fail;
 
-      }
+      if (!noce_emit_bb (emit_b, else_bb, b_simple))
+	goto end_seq_and_fail;
+    }
 
   target = noce_emit_cmove (if_info, x, code, XEXP (if_info->cond, 0),
 			    XEXP (if_info->cond, 1), a, b);