[tuples] Don't ICE if a switch() only has the default label

[Diego Novillo <dnovillo@google.com>]

[-- Attachment #1: Type: text/plain, Size: 185 bytes --]


This fixes a couple of tests in compile.exp.  If a switch only has the
default label, the call to sort_case_labels in gimplify_switch_expr()
was segfaulting as the vector was empty.



[-- Attachment #2: 20070801-fix-switch-exprs-with-0-labels.diff --]
[-- Type: text/x-patch, Size: 1948 bytes --]

2007-08-01  Diego Novillo  <dnovillo@google.com>

	* gimplify.c (gimplify_switch_expr): Do not call sort_case_labels
	if there are no labels other than 'default'.
	* gimple.h (gimple_num_ops, gimple_op, gimple_set_op): Use
	result of GIMPLE_RANGE_CHECK call.

Index: gimplify.c
===================================================================
--- gimplify.c	(revision 127104)
+++ gimplify.c	(working copy)
@@ -1455,7 +1455,9 @@ gimplify_switch_expr (tree *expr_p, gimp
 	  default_case = gimple_label_label (new_default);
 	}
 
-      sort_case_labels (labels);
+      if (!VEC_empty (tree, labels))
+	sort_case_labels (labels);
+
       gimple_switch = build_gimple_switch_vec (SWITCH_COND (switch_expr), 
                                                default_case, labels);
       gimple_add (pre_p, gimple_switch);
Index: gimple.h
===================================================================
--- gimple.h	(revision 127104)
+++ gimple.h	(working copy)
@@ -472,24 +472,24 @@ extern void gimple_range_check_failed (c
 static inline size_t
 gimple_num_ops (gimple gs)
 {
-  GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
-  return gs->with_ops.num_ops;
+  gimple g = GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
+  return g->with_ops.num_ops;
 }
 
 static inline tree
 gimple_op (gimple gs, size_t i)
 {
-  GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
-  gcc_assert (i < gs->with_ops.num_ops);
-  return gs->with_ops.op[i];
+  gimple g = GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
+  gcc_assert (i < g->with_ops.num_ops);
+  return g->with_ops.op[i];
 }
 
 static inline void
 gimple_set_op (gimple gs, size_t i, tree op)
 {
-  GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
-  gcc_assert (i < gs->with_ops.num_ops);
-  gs->with_ops.op[i] = op;
+  gimple g = GIMPLE_RANGE_CHECK (gs, GIMPLE_ASSIGN, GIMPLE_RETURN);
+  gcc_assert (i < g->with_ops.num_ops);
+  g->with_ops.op[i] = op;
 }