[patch] regclass.c: Remove reg_scan_update.

[Kazu Hirata <kazu at codesourcery dot com>]

Hi,

Attached is a patch to remove reg_scan_update and clean up functions
that it calls.

The recent removal of loop.c made reg_scan_update unused.  Now,
reg_scan_update is the only function that calls reg_scan_mark_refs
with the last argument nonzero.  Once we remove reg_scan_update, the
last argument is redundant, so the patch remove that argument.

Tested on x86_64-pc-linux-gnu.  OK to apply?

Kazu Hirata

2006-03-05  Kazu Hirata  <kazu@codesourcery.com>

	* regclass.c (reg_scan_update): Remove.
	(reg_scan_mark_refs): Remove the last argument.
	* rtl.h: Remove the prototype for reg_scan_update.

Index: regclass.c
===================================================================
--- regclass.c	(revision 111703)
+++ regclass.c	(working copy)
@@ -865,7 +865,7 @@ static void record_address_regs (rtx, en
 #ifdef FORBIDDEN_INC_DEC_CLASSES
 static int auto_inc_dec_reg_p (rtx, enum machine_mode);
 #endif
-static void reg_scan_mark_refs (rtx, rtx, int, unsigned int);
+static void reg_scan_mark_refs (rtx, rtx, int);
 
 /* Return the reg_class in which pseudo reg number REGNO is best allocated.
    This function is sometimes called before the info has been computed.
@@ -2286,10 +2286,10 @@ reg_scan (rtx f, unsigned int nregs)
 	if (GET_CODE (pat) == PARALLEL
 	    && XVECLEN (pat, 0) > max_parallel)
 	  max_parallel = XVECLEN (pat, 0);
-	reg_scan_mark_refs (pat, insn, 0, 0);
+	reg_scan_mark_refs (pat, insn, 0);
 
 	if (REG_NOTES (insn))
-	  reg_scan_mark_refs (REG_NOTES (insn), insn, 1, 0);
+	  reg_scan_mark_refs (REG_NOTES (insn), insn, 1);
       }
 
   max_parallel += max_set_parallel;
@@ -2297,39 +2297,11 @@ reg_scan (rtx f, unsigned int nregs)
   timevar_pop (TV_REG_SCAN);
 }
 
-/* Update 'regscan' information by looking at the insns
-   from FIRST to LAST.  Some new REGs have been created,
-   and any REG with number greater than OLD_MAX_REGNO is
-   such a REG.  We only update information for those.  */
-
-void
-reg_scan_update (rtx first, rtx last, unsigned int old_max_regno)
-{
-  rtx insn;
-
-  allocate_reg_info (max_reg_num (), FALSE, FALSE);
-
-  for (insn = first; insn != last; insn = NEXT_INSN (insn))
-    if (INSN_P (insn))
-      {
-	rtx pat = PATTERN (insn);
-	if (GET_CODE (pat) == PARALLEL
-	    && XVECLEN (pat, 0) > max_parallel)
-	  max_parallel = XVECLEN (pat, 0);
-	reg_scan_mark_refs (pat, insn, 0, old_max_regno);
-
-	if (REG_NOTES (insn))
-	  reg_scan_mark_refs (REG_NOTES (insn), insn, 1, old_max_regno);
-      }
-}
-
 /* X is the expression to scan.  INSN is the insn it appears in.
-   NOTE_FLAG is nonzero if X is from INSN's notes rather than its body.
-   We should only record information for REGs with numbers
-   greater than or equal to MIN_REGNO.  */
+   NOTE_FLAG is nonzero if X is from INSN's notes rather than its body.  */
 
 static void
-reg_scan_mark_refs (rtx x, rtx insn, int note_flag, unsigned int min_regno)
+reg_scan_mark_refs (rtx x, rtx insn, int note_flag)
 {
   enum rtx_code code;
   rtx dest;
@@ -2356,43 +2328,35 @@ reg_scan_mark_refs (rtx x, rtx insn, int
       {
 	unsigned int regno = REGNO (x);
 
-	if (regno >= min_regno)
-	  {
-	    if (!note_flag)
-	      REGNO_LAST_UID (regno) = INSN_UID (insn);
-	    if (REGNO_FIRST_UID (regno) == 0)
-	      REGNO_FIRST_UID (regno) = INSN_UID (insn);
-	    /* If we are called by reg_scan_update() (indicated by min_regno
-	       being set), we also need to update the reference count.  */
-	    if (min_regno)
-	      REG_N_REFS (regno)++;
-	  }
+	if (!note_flag)
+	  REGNO_LAST_UID (regno) = INSN_UID (insn);
+	if (REGNO_FIRST_UID (regno) == 0)
+	  REGNO_FIRST_UID (regno) = INSN_UID (insn);
       }
       break;
 
     case EXPR_LIST:
       if (XEXP (x, 0))
-	reg_scan_mark_refs (XEXP (x, 0), insn, note_flag, min_regno);
+	reg_scan_mark_refs (XEXP (x, 0), insn, note_flag);
       if (XEXP (x, 1))
-	reg_scan_mark_refs (XEXP (x, 1), insn, note_flag, min_regno);
+	reg_scan_mark_refs (XEXP (x, 1), insn, note_flag);
       break;
 
     case INSN_LIST:
       if (XEXP (x, 1))
-	reg_scan_mark_refs (XEXP (x, 1), insn, note_flag, min_regno);
+	reg_scan_mark_refs (XEXP (x, 1), insn, note_flag);
       break;
 
     case CLOBBER:
       {
 	rtx reg = XEXP (x, 0);
-	if (REG_P (reg)
-	    && REGNO (reg) >= min_regno)
+	if (REG_P (reg))
 	  {
 	    REG_N_SETS (REGNO (reg))++;
 	    REG_N_REFS (REGNO (reg))++;
 	  }
 	else if (MEM_P (reg))
-	  reg_scan_mark_refs (XEXP (reg, 0), insn, note_flag, min_regno);
+	  reg_scan_mark_refs (XEXP (reg, 0), insn, note_flag);
       }
       break;
 
@@ -2409,8 +2373,7 @@ reg_scan_mark_refs (rtx x, rtx insn, int
       if (GET_CODE (dest) == PARALLEL)
 	max_set_parallel = MAX (max_set_parallel, XVECLEN (dest, 0) - 1);
 
-      if (REG_P (dest)
-	  && REGNO (dest) >= min_regno)
+      if (REG_P (dest))
 	{
 	  REG_N_SETS (REGNO (dest))++;
 	  REG_N_REFS (REGNO (dest))++;
@@ -2430,7 +2393,6 @@ reg_scan_mark_refs (rtx x, rtx insn, int
 
       if (REG_P (SET_DEST (x))
 	  && REGNO (SET_DEST (x)) >= FIRST_PSEUDO_REGISTER
-	  && REGNO (SET_DEST (x)) >= min_regno
 	  /* If the destination pseudo is set more than once, then other
 	     sets might not be to a pointer value (consider access to a
 	     union in two threads of control in the presence of global
@@ -2491,12 +2453,12 @@ reg_scan_mark_refs (rtx x, rtx insn, int
 	for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
 	  {
 	    if (fmt[i] == 'e')
-	      reg_scan_mark_refs (XEXP (x, i), insn, note_flag, min_regno);
+	      reg_scan_mark_refs (XEXP (x, i), insn, note_flag);
 	    else if (fmt[i] == 'E' && XVEC (x, i) != 0)
 	      {
 		int j;
 		for (j = XVECLEN (x, i) - 1; j >= 0; j--)
-		  reg_scan_mark_refs (XVECEXP (x, i, j), insn, note_flag, min_regno);
+		  reg_scan_mark_refs (XVECEXP (x, i, j), insn, note_flag);
 	      }
 	  }
       }
Index: rtl.h
===================================================================
--- rtl.h	(revision 111703)
+++ rtl.h	(working copy)
@@ -2169,7 +2169,6 @@ extern void init_reg_sets (void);
 extern void regclass_init (void);
 extern void regclass (rtx, int);
 extern void reg_scan (rtx, unsigned int);
-extern void reg_scan_update (rtx, rtx, unsigned int);
 extern void fix_register (const char *, int, int);
 extern void init_subregs_of_mode (void);
 extern void record_subregs_of_mode (rtx);