re PR inline-asm/56148 (inline asm matching constraint with different mode)

2013-02-12  Vladimir Makarov  <vmakarov@redhat.com>

	PR inline-asm/56148
	* lra-constraints.c (process_alt_operands): Match early clobber
	operand with itself.  Check conflicts with earlyclobner only if
	the operand is not reloaded.  Prefer to reload conflicting operand
	if earlyclobber and matching operands are the same.

2013-02-12  Vladimir Makarov  <vmakarov@redhat.com>

	PR inline-asm/56148
	* gcc.target/i386/pr56148.c: New test.

From-SVN: r195988

gcc/ChangeLog

+2013-02-12  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR inline-asm/56148
+	* lra-constraints.c (process_alt_operands): Match early clobber
+	operand with itself.  Check conflicts with earlyclobner only if
+	the operand is not reloaded.  Prefer to reload conflicting operand
+	if earlyclobber and matching operands are the same.
+
 2013-02-12  Richard Biener  <rguenther@suse.de>
 
 	PR lto/56297

gcc/lra-constraints.c

@@ -1533,8 +1533,8 @@ process_alt_operands (int only_alternative)
 			if (! curr_static_id->operand[m].early_clobber
 			    || operand_reg[nop] == NULL_RTX
 			    || (find_regno_note (curr_insn, REG_DEAD,
-						 REGNO (operand_reg[nop]))
-						 != NULL_RTX))
+						 REGNO (op))
+				|| REGNO (op) == REGNO (operand_reg[m])))
 			  match_p = true;
 		      }
 		    if (match_p)
@@ -2059,6 +2059,7 @@ process_alt_operands (int only_alternative)
 	  if ((! curr_alt_win[i] && ! curr_alt_match_win[i])
 	      || hard_regno[i] < 0)
 	    continue;
+	  lra_assert (operand_reg[i] != NULL_RTX);
 	  clobbered_hard_regno = hard_regno[i];
 	  CLEAR_HARD_REG_SET (temp_set);
 	  add_to_hard_reg_set (&temp_set, biggest_mode[i], clobbered_hard_regno);
@@ -2073,30 +2074,49 @@ process_alt_operands (int only_alternative)
 	    else if ((curr_alt_matches[j] == i && curr_alt_match_win[j])
 		     || (curr_alt_matches[i] == j && curr_alt_match_win[i]))
 	      continue;
-	    else if (uses_hard_regs_p (*curr_id->operand_loc[j], temp_set))
+	    /* If we don't reload j-th operand, check conflicts.  */
+	    else if ((curr_alt_win[j] || curr_alt_match_win[j])
+		     && uses_hard_regs_p (*curr_id->operand_loc[j], temp_set))
 	      break;
 	  if (j >= n_operands)
 	    continue;
-	  /* We need to reload early clobbered register.  */
-	  for (j = 0; j < n_operands; j++)
-	    if (curr_alt_matches[j] == i)
-	      {
-		curr_alt_match_win[j] = false;
-		losers++;
-		overall += LRA_LOSER_COST_FACTOR;
-	      }
-	  if (! curr_alt_match_win[i])
-	    curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = i;
+	  /* If earlyclobber operand conflicts with another
+	     non-matching operand which is actually the same register
+	     as the earlyclobber operand, it is better to reload the
+	     another operand as an operand matching the earlyclobber
+	     operand can be also the same.  */
+	  if (operand_reg[j] != NULL_RTX && ! curr_alt_match_win[j]
+	      && REGNO (operand_reg[i]) == REGNO (operand_reg[j]))
+	    {
+	      curr_alt_win[j] = false;
+	      curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = j;
+	      losers++;
+	      overall += LRA_LOSER_COST_FACTOR;
+	    }
 	  else
 	    {
-	      /* Remember pseudos used for match reloads are never
-		 inherited.  */
-	      lra_assert (curr_alt_matches[i] >= 0);
-	      curr_alt_win[curr_alt_matches[i]] = false;
+	      /* We need to reload early clobbered register and the
+		 matched registers.  */
+	      for (j = 0; j < n_operands; j++)
+		if (curr_alt_matches[j] == i)
+		  {
+		    curr_alt_match_win[j] = false;
+		    losers++;
+		    overall += LRA_LOSER_COST_FACTOR;
+		  }
+	      if (! curr_alt_match_win[i])
+		curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = i;
+	      else
+		{
+		  /* Remember pseudos used for match reloads are never
+		     inherited.  */
+		  lra_assert (curr_alt_matches[i] >= 0);
+		  curr_alt_win[curr_alt_matches[i]] = false;
+		}
+	      curr_alt_win[i] = curr_alt_match_win[i] = false;
+	      losers++;
+	      overall += LRA_LOSER_COST_FACTOR;
 	    }
-	  curr_alt_win[i] = curr_alt_match_win[i] = false;
-	  losers++;
-	  overall += LRA_LOSER_COST_FACTOR;
 	}
       small_class_operands_num = 0;
       for (nop = 0; nop < n_operands; nop++)

gcc/testsuite/ChangeLog

+2013-02-12  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR inline-asm/56148
+	* gcc.target/i386/pr56148.c: New test.
+
 2013-02-12  Dominique d'Humieres  <dominiq@lps.ens.fr>
 	    Tobias Burnus  <burnus@net-b.de>
 

gcc/testsuite/gcc.target/i386/pr56148.c

+/* PR inline-asm/56148 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+void
+foo (void)
+{
+  unsigned char e[16];
+  unsigned long a, b, c, d;
+  __asm__ __volatile__ ("" : "=d" (a), "=&c" (c), "=&D" (d), "=&a" (b)
+               : "0" (-1U), "mr" (e), "1" (128 >> 5), "2" (e), "3" (-1U));
+}