From patchwork Sun Jan 20 19:12:05 2013
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: one more patch to fix PR55433
From: Vladimir Makarov <vmakarov@redhat.com>
X-Patchwork-Id: 213974
Message-Id: <50FC4185.8010507@redhat.com>
To: GCC Patches <gcc-patches@gcc.gnu.org>
Date: Sun, 20 Jan 2013 14:12:05 -0500

After submitting the previous patch for PR55433, Steven found that 
powerpc LRA is broken as the original insn for secondary memory reload 
can not be used in some cases.

The following patch fixes the problem.  The patch might be not necessary 
for x86/x86-64 but I submitted it too.

The patch was successfully bootstrapped and tested on x86/x86-64.

Committed as rev.195322.

2013-01-20  Vladimir Makarov  <vmakarov@redhat.com>

         PR target/55433
         * lra-constraints.c (curr_insn_transform): Don't reuse original
         insn for secondary memory move when memory mode should be
         different.


Index: lra-constraints.c
===================================================================
--- lra-constraints.c	(revision 195321)
+++ lra-constraints.c	(working copy)
@@ -2791,7 +2791,7 @@ curr_insn_transform (void)
 
   if (use_sec_mem_p)
     {
-      rtx new_reg, src, dest, rld, rld_subst;
+      rtx new_reg, src, dest, rld;
       enum machine_mode sec_mode, rld_mode;
 
       lra_assert (sec_mem_p);
@@ -2811,17 +2811,28 @@ curr_insn_transform (void)
 				    NO_REGS, "secondary");
       /* If the mode is changed, it should be wider.  */
       lra_assert (GET_MODE_SIZE (sec_mode) >= GET_MODE_SIZE (rld_mode));
-      rld_subst = (sec_mode == rld_mode ? new_reg : gen_lowpart_SUBREG (rld_mode, new_reg));
-      if (dest == rld)
-	{
-	  *curr_id->operand_loc[0] = rld_subst;
+      if (sec_mode != rld_mode)
+        {
+	  /* If the target says specifically to use another mode for
+	     secondary memory moves we can not reuse the original
+	     insn.  */
+         after = emit_spill_move (false, new_reg, dest);
+         lra_process_new_insns (curr_insn, NULL_RTX, after,
+                                "Inserting the sec. move");
+         before = emit_spill_move (true, new_reg, src);
+         lra_process_new_insns (curr_insn, before, NULL_RTX, "Changing on");
+         lra_set_insn_deleted (curr_insn);
+       }
+      else if (dest == rld)
+       {
+         *curr_id->operand_loc[0] = new_reg;
 	  after = emit_spill_move (false, new_reg, dest);
 	  lra_process_new_insns (curr_insn, NULL_RTX, after,
 				 "Inserting the sec. move");
 	}
       else
 	{
-	  *curr_id->operand_loc[1] = rld_subst;
+	  *curr_id->operand_loc[1] = new_reg;
 	  before = emit_spill_move (true, new_reg, src);
 	  lra_process_new_insns (curr_insn, before, NULL_RTX,
 				 "Inserting the sec. move");