2009-02-25 Paolo Bonzini <bonzini@gnu.org>

	* regmove.c (discover_flags_reg, flags_set_1, mark_flags_life_zones,
	flags_set_1_rtx, flags_set_1_set): Delete.
	(regmove_optimize): Do not call mark_flags_life_zones.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@144425 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 0 insertions, 173 deletions

diff --git a/gcc/regmove.c b/gcc/regmove.c
index 2a638197a7a..9342cade624 100644
--- a/gcc/regmove.c
+++ b/gcc/regmove.c
@@ -58,10 +58,6 @@ struct match {
   int early_clobber[MAX_RECOG_OPERANDS];
 };
 
-static rtx discover_flags_reg (void);
-static void mark_flags_life_zones (rtx);
-static void flags_set_1 (rtx, const_rtx, void *);
-
 static int find_matches (rtx, struct match *);
 static int regclass_compatible_p (int, int);
 static int fixup_match_2 (rtx, rtx, rtx, rtx);
@@ -79,171 +75,6 @@ regclass_compatible_p (int class0, int class1)
 }
 
 
-/* Determine if the pattern generated by add_optab has a clobber,
-   such as might be issued for a flags hard register.  To make the
-   code elsewhere simpler, we handle cc0 in this same framework.
-
-   Return the register if one was discovered.  Return NULL_RTX if
-   if no flags were found.  Return pc_rtx if we got confused.  */
-
-static rtx
-discover_flags_reg (void)
-{
-  rtx tmp;
-  tmp = gen_rtx_REG (word_mode, 10000);
-  tmp = gen_add3_insn (tmp, tmp, const2_rtx);
-
-  /* If we get something that isn't a simple set, or a
-     [(set ..) (clobber ..)], this whole function will go wrong.  */
-  if (GET_CODE (tmp) == SET)
-    return NULL_RTX;
-  else if (GET_CODE (tmp) == PARALLEL)
-    {
-      int found;
-
-      if (XVECLEN (tmp, 0) != 2)
-	return pc_rtx;
-      tmp = XVECEXP (tmp, 0, 1);
-      if (GET_CODE (tmp) != CLOBBER)
-	return pc_rtx;
-      tmp = XEXP (tmp, 0);
-
-      /* Don't do anything foolish if the md wanted to clobber a
-	 scratch or something.  We only care about hard regs.
-	 Moreover we don't like the notion of subregs of hard regs.  */
-      if (GET_CODE (tmp) == SUBREG
-	  && REG_P (SUBREG_REG (tmp))
-	  && REGNO (SUBREG_REG (tmp)) < FIRST_PSEUDO_REGISTER)
-	return pc_rtx;
-      found = (REG_P (tmp) && REGNO (tmp) < FIRST_PSEUDO_REGISTER);
-
-      return (found ? tmp : NULL_RTX);
-    }
-
-  return pc_rtx;
-}
-
-/* It is a tedious task identifying when the flags register is live and
-   when it is safe to optimize.  Since we process the instruction stream
-   multiple times, locate and record these live zones by marking the
-   mode of the instructions --
-
-   QImode is used on the instruction at which the flags becomes live.
-
-   HImode is used within the range (exclusive) that the flags are
-   live.  Thus the user of the flags is not marked.
-
-   All other instructions are cleared to VOIDmode.  */
-
-/* Used to communicate with flags_set_1.  */
-static rtx flags_set_1_rtx;
-static int flags_set_1_set;
-
-static void
-mark_flags_life_zones (rtx flags)
-{
-  int flags_regno;
-  int flags_nregs;
-  basic_block block;
-
-#ifdef HAVE_cc0
-  /* If we found a flags register on a cc0 host, bail.  */
-  if (flags == NULL_RTX)
-    flags = cc0_rtx;
-  else if (flags != cc0_rtx)
-    flags = pc_rtx;
-#endif
-
-  /* Simple cases first: if no flags, clear all modes.  If confusing,
-     mark the entire function as being in a flags shadow.  */
-  if (flags == NULL_RTX || flags == pc_rtx)
-    {
-      enum machine_mode mode = (flags ? HImode : VOIDmode);
-      rtx insn;
-      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
-	PUT_MODE (insn, mode);
-      return;
-    }
-
-#ifdef HAVE_cc0
-  flags_regno = -1;
-  flags_nregs = 1;
-#else
-  flags_regno = REGNO (flags);
-  flags_nregs = hard_regno_nregs[flags_regno][GET_MODE (flags)];
-#endif
-  flags_set_1_rtx = flags;
-
-  /* Process each basic block.  */
-  FOR_EACH_BB_REVERSE (block)
-    {
-      rtx insn, end;
-      int live;
-
-      insn = BB_HEAD (block);
-      end = BB_END (block);
-
-      /* Look out for the (unlikely) case of flags being live across
-	 basic block boundaries.  */
-      live = 0;
-#ifndef HAVE_cc0
-      {
-	int i;
-	for (i = 0; i < flags_nregs; ++i)
-	  live |= REGNO_REG_SET_P (df_get_live_in (block), flags_regno + i);
-      }
-#endif
-
-      while (1)
-	{
-	  /* Process liveness in reverse order of importance --
-	     alive, death, birth.  This lets more important info
-	     overwrite the mode of lesser info.  */
-
-	  if (INSN_P (insn))
-	    {
-#ifdef HAVE_cc0
-	      /* In the cc0 case, death is not marked in reg notes,
-		 but is instead the mere use of cc0 when it is alive.  */
-	      if (live && reg_mentioned_p (cc0_rtx, PATTERN (insn)))
-		live = 0;
-#else
-	      /* In the hard reg case, we watch death notes.  */
-	      if (live && find_regno_note (insn, REG_DEAD, flags_regno))
-		live = 0;
-#endif
-	      PUT_MODE (insn, (live ? HImode : VOIDmode));
-
-	      /* In either case, birth is denoted simply by its presence
-		 as the destination of a set.  */
-	      flags_set_1_set = 0;
-	      note_stores (PATTERN (insn), flags_set_1, NULL);
-	      if (flags_set_1_set)
-		{
-		  live = 1;
-		  PUT_MODE (insn, QImode);
-		}
-	    }
-	  else
-	    PUT_MODE (insn, (live ? HImode : VOIDmode));
-
-	  if (insn == end)
-	    break;
-	  insn = NEXT_INSN (insn);
-	}
-    }
-}
-
-/* A subroutine of mark_flags_life_zones, called through note_stores.  */
-
-static void
-flags_set_1 (rtx x, const_rtx pat, void *data ATTRIBUTE_UNUSED)
-{
-  if (GET_CODE (pat) == SET
-      && reg_overlap_mentioned_p (x, flags_set_1_rtx))
-    flags_set_1_set = 1;
-}
-
 #ifdef AUTO_INC_DEC
 
 /* Find the place in the rtx X where REG is used as a memory address.
@@ -1077,10 +908,6 @@ regmove_optimize (rtx f, int nregs)
   regstat_init_n_sets_and_refs ();
   regstat_compute_ri ();
 
-  /* Find out where a potential flags register is live, and so that we
-     can suppress some optimizations in those zones.  */
-  mark_flags_life_zones (discover_flags_reg ());
-
   regno_src_regno = XNEWVEC (int, nregs);
   for (i = nregs; --i >= 0; )
     regno_src_regno[i] = -1;