re PR middle-end/26300 (ICE in trunc_int_for_mode)

	PR middle-end/26300
	* combine.c (make_extraction): Bail out if ORIG_POS is negative.

	* gcc.c-torture/compile/20060215-1.c: New test.

From-SVN: r111116

gcc/ChangeLog

 2006-02-15  Jakub Jelinek  <jakub@redhat.com>
 
+	PR middle-end/26300
+	* combine.c (make_extraction): Bail out if ORIG_POS is negative.
+
 	* tree.h (struct tree_omp_clause): Use OMP_CLAUSE_CODE rather
 	than TREE_CODE as index into omp_clause_num_ops array.
 

gcc/combine.c

@@ -6249,6 +6249,9 @@ make_extraction (enum machine_mode mode, rtx inner, HOST_WIDE_INT pos,
 	      || orig_pos + len > GET_MODE_BITSIZE (wanted_inner_mode)))
 	return 0;
 
+      if (orig_pos < 0)
+	return 0;
+
       inner = force_to_mode (inner, wanted_inner_mode,
 			     pos_rtx
 			     || len + orig_pos >= HOST_BITS_PER_WIDE_INT

gcc/testsuite/ChangeLog

+2006-02-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/26300
+	* gcc.c-torture/compile/20060215-1.c: New test.
+
 2006-02-14  Roger Sayle  <roger@eyesopen.com>
 
 	PR middle-end/23670

gcc/testsuite/gcc.c-torture/compile/20060215-1.c

+/* PR middle-end/26300 */
+
+struct S
+{
+  char c;
+  struct S *d;
+  struct S *e;
+};
+extern struct S *u, *v;
+extern void fn1 (struct S *) __attribute__ ((noreturn));
+void fn2 (struct S *);
+
+static inline struct S *
+fn3 (struct S *x)
+{
+  if (x->c != 6)
+    fn1 (0);
+  return (struct S *) x;
+}
+
+static inline int
+fn4 (struct S *x)
+{
+  if (x != u)
+    return 3;
+  fn2 (x);
+  return 0;
+}
+
+int
+test (struct S *x)
+{
+  struct S *r;
+  int m = 0;
+
+  for (r = x; r != v; r = (fn3 (r)->d))
+    if (r->c != 6)
+      fn1 (x);
+    else
+      m |= 1 << (fn4 (fn3 (r)->e) - 1);
+  return m;
+}