re PR rtl-optimization/56246 (ICE in assign_by_spills, at lra-assigns.c:1262)

2013-02-08  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/56246
	* lra-constraints.c (simplify_operand_subreg): Try tor reuse
	reload pseudo.
	* lra.c (lra): Clear lra_optional_reload_pseudos only when all
	constraints are satisfied.

2013-02-08  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/56246
	* gcc.target/i386/pr56246.c: New test.

From-SVN: r195902

gcc/ChangeLog

+2013-02-08  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/56246
+	* lra-constraints.c (simplify_operand_subreg): Try tor reuse
+	reload pseudo.
+	* lra.c (lra): Clear lra_optional_reload_pseudos only when all
+	constraints are satisfied.
+
 2013-02-08  Jeff Law  <law@redhat.com>
 
 	PR debug/53948

gcc/lra-constraints.c

@@ -1213,24 +1213,26 @@ simplify_operand_subreg (int nop, enum machine_mode reg_mode)
       enum reg_class rclass
 	= (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
 
-      new_reg = lra_create_new_reg_with_unique_value (reg_mode, reg, rclass,
-						      "subreg reg");
-      bitmap_set_bit (&lra_optional_reload_pseudos, REGNO (new_reg));
-      if (type != OP_OUT
-	  || GET_MODE_SIZE (GET_MODE (reg)) > GET_MODE_SIZE (mode))
+      if (get_reload_reg (curr_static_id->operand[nop].type, reg_mode, reg,
+			  rclass, "subreg reg", &new_reg))
 	{
-	  push_to_sequence (before);
-	  lra_emit_move (new_reg, reg);
-	  before = get_insns ();
-	  end_sequence ();
-	}
-      if (type != OP_IN)
-	{
-	  start_sequence ();
-	  lra_emit_move (reg, new_reg);
-	  emit_insn (after);
-	  after = get_insns ();
-	  end_sequence ();
+	  bitmap_set_bit (&lra_optional_reload_pseudos, REGNO (new_reg));
+	  if (type != OP_OUT
+	      || GET_MODE_SIZE (GET_MODE (reg)) > GET_MODE_SIZE (mode))
+	    {
+	      push_to_sequence (before);
+	      lra_emit_move (new_reg, reg);
+	      before = get_insns ();
+	      end_sequence ();
+	    }
+	  if (type != OP_IN)
+	    {
+	      start_sequence ();
+	      lra_emit_move (reg, new_reg);
+	      emit_insn (after);
+	      after = get_insns ();
+	      end_sequence ();
+	    }
 	}
       SUBREG_REG (operand) = new_reg;
       lra_process_new_insns (curr_insn, before, after,

gcc/lra.c

@@ -2272,7 +2272,6 @@ lra (FILE *f)
     {
       for (;;)
 	{
-	  bitmap_clear (&lra_optional_reload_pseudos);
 	  /* We should try to assign hard registers to scratches even
 	     if there were no RTL transformations in
 	     lra_constraints.  */
@@ -2311,6 +2310,7 @@ lra (FILE *f)
 		live_p = false;
 	    }
 	}
+      bitmap_clear (&lra_optional_reload_pseudos);
       bitmap_clear (&lra_inheritance_pseudos);
       bitmap_clear (&lra_split_regs);
       if (! lra_need_for_spills_p ())

gcc/testsuite/ChangeLog

+2013-02-08  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/56246
+	* gcc.target/i386/pr56246.c: New test.
+
 2013-02-08  Jeff Law  <law@redhat.com>
 
 	PR debug/53948

gcc/testsuite/gcc.target/i386/pr56246.c

+/* PR target/56225 */
+/* { dg-do compile { target { ia32 } } } */
+/* { dg-options "-O2 -fno-omit-frame-pointer -march=i686 -fpic" } */
+
+void NoBarrier_AtomicExchange (long long *ptr) {
+  while (__sync_val_compare_and_swap (ptr, 1, 0) );
+}