re PR debug/67043 (-fcompare-debug failure with -O3)

2015-08-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR tree-optimization/67043
    * loop-invariant.c (move_invariant_reg): Recompute luids in loop
    preheader after hoisting invariant in it.
    (find_defs): Force recomputation of all luids.

    gcc/testsuite/
    PR tree-optimization/67043
    * gcc.dg/pr67043.c: New test.

From-SVN: r226540

gcc/ChangeLog

+2015-08-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/67043
+	* loop-invariant.c (move_invariant_reg): Recompute luids in loop
+	preheader after hoisting invariant in it.
+	(find_defs): Force recomputation of all luids.
+
 2015-08-03  Peter Bergner  <bergner@vnet.ibm.com>
 
 	* config/rs6000/htm.md (tabort.): Restrict the source operand to

gcc/loop-invariant.c

@@ -676,6 +676,8 @@ find_defs (struct loop *loop)
   df_remove_problem (df_chain);
   df_process_deferred_rescans ();
   df_chain_add_problem (DF_UD_CHAIN);
+  df_live_add_problem ();
+  df_live_set_all_dirty ();
   df_set_flags (DF_RD_PRUNE_DEAD_DEFS);
   df_analyze_loop (loop);
   check_invariant_table_size ();
@@ -1629,6 +1631,7 @@ move_invariant_reg (struct loop *loop, unsigned invno)
 	fprintf (dump_file, "Invariant %d moved without introducing a new "
 			    "temporary register\n", invno);
       reorder_insns (inv->insn, inv->insn, BB_END (preheader));
+      df_recompute_luids (preheader);
 
       /* If there is a REG_EQUAL note on the insn we just moved, and the
 	 insn is in a basic block that is not always executed or the note

gcc/testsuite/ChangeLog

+2015-08-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR tree-optimization/67043
+	* gcc.dg/pr67043.c: New test.
+
 2015-08-03  Peter Bergner  <bergner@vnet.ibm.com>
 
 	* gcc.target/powerpc/htm-tabort-no-r0.c: New test.

gcc/testsuite/gcc.dg/pr67043.c

+/* { dg-do compile } */
+/* { dg-options "-O3 -fcompare-debug -w" } */
+
+extern void rt_mutex_owner (void);
+extern void rt_mutex_deadlock_account_lock (int);
+extern void signal_pending (void);
+__typeof__ (int *) a;
+int b;
+
+int
+try_to_take_rt_mutex (int p1) {
+  rt_mutex_owner ();
+  if (b)
+    return 0;
+  rt_mutex_deadlock_account_lock (p1);
+  return 1;
+}
+
+void
+__rt_mutex_slowlock (int p1) {
+  int c;
+  for (;;) {
+    c = ({
+      asm ("" : "=r"(a));
+      a;
+    });
+    if (try_to_take_rt_mutex (c))
+      break;
+    if (__builtin_expect (p1 == 0, 0))
+      signal_pending ();
+  }
+}