re PR debug/44028 (-fcompare-debug failure (length) with -O3 -fsched-pressure -fschedule-insns)

	PR debug/44028
	* haifa-sched.c (schedule_insn): When clearing INSN_VAR_LOCATION_LOC,
	clear also INSN_REG_USE_LIST.

	* gcc.dg/pr44028.c: New test.

From-SVN: r159240

gcc/ChangeLog

+2010-05-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/44028
+	* haifa-sched.c (schedule_insn): When clearing INSN_VAR_LOCATION_LOC,
+	clear also INSN_REG_USE_LIST.
+
 2010-05-10  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* config/mips/mips.c (TARGET_SMALL_REGISTER_CLASSES_FOR_MODE_P): Undef.

gcc/haifa-sched.c

@@ -1695,6 +1695,7 @@ schedule_insn (rtx insn)
 	 sd_iterator_cond (&sd_it, &dep);)
       {
 	rtx dbg = DEP_PRO (dep);
+	struct reg_use_data *use, *next;
 
 	gcc_assert (DEBUG_INSN_P (dbg));
 
@@ -1716,6 +1717,14 @@ schedule_insn (rtx insn)
 	INSN_VAR_LOCATION_LOC (dbg) = gen_rtx_UNKNOWN_VAR_LOC ();
 	df_insn_rescan (dbg);
 
+	/* Unknown location doesn't use any registers.  */
+	for (use = INSN_REG_USE_LIST (dbg); use != NULL; use = next)
+	  {
+	    next = use->next_insn_use;
+	    free (use);
+	  }
+	INSN_REG_USE_LIST (dbg) = NULL;
+
 	/* We delete rather than resolve these deps, otherwise we
 	   crash in sched_free_deps(), because forward deps are
 	   expected to be released before backward deps.  */

gcc/testsuite/ChangeLog

+2010-05-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/44028
+	* gcc.dg/pr44028.c: New test.
+
 2010-05-08  Daniel Franke  <franke.daniel@gmail.com>
 
 	PR fortran/27866

gcc/testsuite/gcc.dg/pr44028.c

+/* PR debug/44028 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -fcompare-debug" } */
+/* { dg-options "-O3 -fsched-pressure -fschedule-insns -fcompare-debug" { target i?86-*-* x86_64-*-* } } */
+
+struct S { int val[16]; };
+
+static inline int
+bar (struct S x)
+{
+  long double pc = 0;
+  int i;
+  for (i = 0; i < 16; i++)
+    pc += x.val[i];
+  return pc;
+}
+
+int
+foo (struct S x)
+{
+  return bar (x);
+}