re PR rtl-optimization/65321 (ICE on valid code at -O2 and -O3 with -g enabled in decompose, at rtl.h:2007)

PR rtl-optimization/65321
	* cfgexpand.c (expand_debug_expr): Ensure shift amount isn't wider
	than shift mode.
	* var-tracking.c (use_narrower_mode): Likewise.

	* gcc.dg/pr65321.c: New test.

From-SVN: r221298

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2015-03-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/65321
+	* cfgexpand.c (expand_debug_expr): Ensure shift amount isn't wider
+	than shift mode.
+	* var-tracking.c (use_narrower_mode): Likewise.
+
 2015-03-10  Jan Hubicka  <hubicka@ucw.cz>
 
 	PR tree-optimization/65355

gcc/cfgexpand.c

@@ -3921,6 +3921,31 @@ expand_debug_expr (tree exp)
       op1 = expand_debug_expr (TREE_OPERAND (exp, 1));
       if (!op1)
 	return NULL_RTX;
+      switch (TREE_CODE (exp))
+	{
+	case LSHIFT_EXPR:
+	case RSHIFT_EXPR:
+	case LROTATE_EXPR:
+	case RROTATE_EXPR:
+	case WIDEN_LSHIFT_EXPR:
+	  /* Ensure second operand isn't wider than the first one.  */
+	  inner_mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 1)));
+	  if (SCALAR_INT_MODE_P (inner_mode))
+	    {
+	      machine_mode opmode = mode;
+	      if (VECTOR_MODE_P (mode))
+		opmode = GET_MODE_INNER (mode);
+	      if (SCALAR_INT_MODE_P (opmode)
+		  && (GET_MODE_PRECISION (opmode)
+		      < GET_MODE_PRECISION (inner_mode)))
+		op1 = simplify_gen_subreg (opmode, op1, inner_mode,
+					   subreg_lowpart_offset (opmode,
+								  inner_mode));
+	    }
+	  break;
+	default:
+	  break;
+	}
       /* Fall through.  */
 
     unary:

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2015-03-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/65321
+	* gcc.dg/pr65321.c: New test.
+
 2015-03-10  Jan Hubicka  <hubicka@ucw.cz>
 
 	PR tree-optimization/65355

gcc/testsuite/gcc.dg/pr65321.c

@@ -0,0 +1,31 @@
+/* PR rtl-optimization/65321 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -g" } */
+
+int a, b, c, d, e;
+
+int
+foo (void)
+{
+  int h;
+  char i;
+  for (; c > 0;)
+    {
+      for (d = 0; d < 2; d++)
+	{
+	  i = 1 << d;
+	  if (i - a)
+	    {
+	      e = b = 0;
+	      for (; c; c--)
+		d = 127;
+	    }
+	}
+      h = ~d;
+      if (h > c)
+	for (;;)
+	  ;
+      return 0;
+    }
+  return 0;
+}

gcc/var-tracking.c

@@ -1011,7 +1011,13 @@ use_narrower_mode (rtx x, machine_mode mode, machine_mode wmode)
       return simplify_gen_binary (GET_CODE (x), mode, op0, op1);
     case ASHIFT:
       op0 = use_narrower_mode (XEXP (x, 0), mode, wmode);
-      return simplify_gen_binary (ASHIFT, mode, op0, XEXP (x, 1));
+      op1 = XEXP (x, 1);
+      /* Ensure shift amount is not wider than mode.  */
+      if (GET_MODE (op1) == VOIDmode)
+	op1 = lowpart_subreg (mode, op1, wmode);
+      else if (GET_MODE_PRECISION (mode) < GET_MODE_PRECISION (GET_MODE (op1)))
+	op1 = lowpart_subreg (mode, op1, GET_MODE (op1));
+      return simplify_gen_binary (ASHIFT, mode, op0, op1);
     default:
       gcc_unreachable ();
     }