genattrtab memory usage reduction

[Matt Kraai <kraai at alumni dot carnegiemellon dot edu>]

Howdy,

In genattrtab, there is no need to copy rtxs.  Doing so only
consumes extra memory, causing my system to run out when
bootstrapping (64 megabytes on i586-pc-linux-gnu).

With the following patch, GCC bootstraps on my system.  I can't
check for any regressions as I don't have a working baseline.  OK
to commit?

Matt

2001-05-20  Matt Kraai  <kraai@alumni.carnegiemellon.edu>

	* genattrtab.c (attr_copy_rtx): Remove it.
	(simplify_test_exp): Remove temp_obstack references.
	(simplify_test_exp): Remove call to attr_copy_rtx.
	(expand_units): Likewise.
	(optimize_attrs): Likewise.

Index: gcc/genattrtab.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/genattrtab.c,v
retrieving revision 1.90
diff -c -3 -p -r1.90 genattrtab.c
*** genattrtab.c	2001/04/13 21:10:14	1.90
--- genattrtab.c	2001/05/21 04:05:55
*************** static void extend_range	PARAMS ((struct
*** 459,465 ****
  static rtx attr_eq		PARAMS ((const char *, const char *));
  static const char *attr_numeral	PARAMS ((int));
  static int attr_equal_p		PARAMS ((rtx, rtx));
- static rtx attr_copy_rtx	PARAMS ((rtx));
  static int attr_rtx_cost 	PARAMS ((rtx));
  
  #define oballoc(size) obstack_alloc (hash_obstack, size)
--- 459,464 ----
*************** attr_equal_p (x, y)
*** 829,920 ****
  		     && rtx_equal_p (x, y)));
  }
  
- /* Copy an attribute value expression,
-    descending to all depths, but not copying any
-    permanent hashed subexpressions.  */
- 
- static rtx
- attr_copy_rtx (orig)
-      register rtx orig;
- {
-   register rtx copy;
-   register int i, j;
-   register RTX_CODE code;
-   register const char *format_ptr;
- 
-   /* No need to copy a permanent object.  */
-   if (RTX_INTEGRATED_P (orig))
-     return orig;
- 
-   code = GET_CODE (orig);
- 
-   switch (code)
-     {
-     case REG:
-     case QUEUED:
-     case CONST_INT:
-     case CONST_DOUBLE:
-     case SYMBOL_REF:
-     case CODE_LABEL:
-     case PC:
-     case CC0:
-       return orig;
- 
-     default:
-       break;
-     }
- 
-   copy = rtx_alloc (code);
-   PUT_MODE (copy, GET_MODE (orig));
-   copy->in_struct = orig->in_struct;
-   copy->volatil = orig->volatil;
-   copy->unchanging = orig->unchanging;
-   copy->integrated = orig->integrated;
- 
-   format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
- 
-   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
-     {
-       switch (*format_ptr++)
- 	{
- 	case 'e':
- 	  XEXP (copy, i) = XEXP (orig, i);
- 	  if (XEXP (orig, i) != NULL)
- 	    XEXP (copy, i) = attr_copy_rtx (XEXP (orig, i));
- 	  break;
- 
- 	case 'E':
- 	case 'V':
- 	  XVEC (copy, i) = XVEC (orig, i);
- 	  if (XVEC (orig, i) != NULL)
- 	    {
- 	      XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
- 	      for (j = 0; j < XVECLEN (copy, i); j++)
- 		XVECEXP (copy, i, j) = attr_copy_rtx (XVECEXP (orig, i, j));
- 	    }
- 	  break;
- 
- 	case 'n':
- 	case 'i':
- 	  XINT (copy, i) = XINT (orig, i);
- 	  break;
- 
- 	case 'w':
- 	  XWINT (copy, i) = XWINT (orig, i);
- 	  break;
- 
- 	case 's':
- 	case 'S':
- 	  XSTR (copy, i) = XSTR (orig, i);
- 	  break;
- 
- 	default:
- 	  abort ();
- 	}
-     }
-   return copy;
- }
- 
  /* Given a test expression for an attribute, ensure it is validly formed.
     IS_CONST indicates whether the expression is constant for each compiler
     run (a constant expression may not test any particular insn).
--- 828,833 ----
*************** expand_units ()
*** 1961,1967 ****
  	{
  	  XEXP (newexp, 0) = unit->condexp;
  	  XEXP (newexp, 1) = make_numeric_value (1 << unit->num);
! 	  unitsmask = operate_exp (ORX_OP, unitsmask, attr_copy_rtx (newexp));
  	}
      }
  
--- 1874,1880 ----
  	{
  	  XEXP (newexp, 0) = unit->condexp;
  	  XEXP (newexp, 1) = make_numeric_value (1 << unit->num);
! 	  unitsmask = operate_exp (ORX_OP, unitsmask, newexp);
  	}
      }
  
*************** simplify_test_exp (exp, insn_code, insn_
*** 3464,3476 ****
  	    if (ie->insn_code == insn_code)
  	      {
  		rtx x;
- 		struct obstack *old = rtl_obstack;
- 		rtl_obstack = temp_obstack;
  		x = evaluate_eq_attr (exp, av->value, insn_code, insn_index);
  		x = SIMPLIFY_TEST_EXP (x, insn_code, insn_index);
- 		rtl_obstack = old;
  		if (attr_rtx_cost(x) < 20)
! 		  return attr_copy_rtx (x);
  	      }
        break;
  
--- 3377,3386 ----
  	    if (ie->insn_code == insn_code)
  	      {
  		rtx x;
  		x = evaluate_eq_attr (exp, av->value, insn_code, insn_index);
  		x = SIMPLIFY_TEST_EXP (x, insn_code, insn_index);
  		if (attr_rtx_cost(x) < 20)
! 		  return x;
  	      }
        break;
  
*************** optimize_attrs ()
*** 3585,3591 ****
  	      rtl_obstack = old;
  	      if (newexp != av->value)
  		{
- 		  newexp = attr_copy_rtx (newexp);
  		  remove_insn_ent (av, ie);
  		  av = get_attr_value (newexp, attr, ie->insn_code);
  		  iv->av = av;
--- 3495,3500 ----