pa.c

gcc库的原代码,对编程有很大帮助.

/* Subroutines for insn-output.c for HPPA.
   Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
   Contributed by Tim Moore ([e-mail]), based on sparc.c

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include <stdio.h>
#include "config.h"
#include "rtl.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "real.h"
#include "insn-config.h"
#include "conditions.h"
#include "insn-flags.h"
#include "output.h"
#include "insn-attr.h"
#include "flags.h"
#include "tree.h"
#include "c-tree.h"
#include "expr.h"
#include "obstack.h"

/* Save the operands last given to a compare for use when we
   generate a scc or bcc insn.  */

rtx hppa_compare_op0, hppa_compare_op1;
enum cmp_type hppa_branch_type;

/* Which cpu we are scheduling for.  */
enum processor_type pa_cpu;

/* String to hold which cpu we are scheduling for.  */
char *pa_cpu_string;

/* Set by the FUNCTION_PROFILER macro. */
int hp_profile_labelno;

/* Counts for the number of callee-saved general and floating point
   registers which were saved by the current function's prologue.  */
static int gr_saved, fr_saved;

static rtx find_addr_reg ();

/* Keep track of the number of bytes we have output in the CODE subspaces
   during this compilation so we'll know when to emit inline long-calls.  */

unsigned int total_code_bytes;

/* Variables to handle plabels that we discover are necessary at assembly
   output time.  They are output after the current function.  */

struct defer_plab
{
  rtx internal_label;
  rtx symbol;
} *deferred_plabels = 0;
int n_deferred_plabels = 0;

void
override_options ()
{
  /* Default to 700 scheduling which is reasonable for older 800 processors
     correct for the 700s, and not too bad for the 7100s and 7100LCs.  */
  if (pa_cpu_string == NULL
      || ! strcmp (pa_cpu_string, "700"))
    {
      pa_cpu_string = "700";
      pa_cpu = PROCESSOR_700;
    }
  else if (! strcmp (pa_cpu_string, "7100"))
    {
      pa_cpu_string = "7100";
      pa_cpu = PROCESSOR_7100;
    }
  else if (! strcmp (pa_cpu_string, "7100LC"))
    {
      pa_cpu_string = "7100LC";
      pa_cpu = PROCESSOR_7100LC;
    }
  else
    {
      warning ("Unknown -mschedule= option (%s).\nValid options are 700, 7100 and 7100LC\n", pa_cpu_string);
    }
}


/* Return non-zero only if OP is a register of mode MODE,
   or CONST0_RTX.  */
int
reg_or_0_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (op == CONST0_RTX (mode) || register_operand (op, mode));
}

/* Return non-zero if OP is suitable for use in a call to a named
   function.

   (???) For 2.5 try to eliminate either call_operand_address or
   function_label_operand, they perform very similar functions.  */
int
call_operand_address (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (CONSTANT_P (op) && ! TARGET_PORTABLE_RUNTIME);
}

/* Return 1 if X contains a symbolic expression.  We know these
   expressions will have one of a few well defined forms, so
   we need only check those forms.  */
int
symbolic_expression_p (x)
     register rtx x;
{

  /* Strip off any HIGH. */
  if (GET_CODE (x) == HIGH)
    x = XEXP (x, 0);

  return (symbolic_operand (x, VOIDmode));
}

int
symbolic_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  switch (GET_CODE (op))
    {
    case SYMBOL_REF:
    case LABEL_REF:
      return 1;
    case CONST:
      op = XEXP (op, 0);
      return ((GET_CODE (XEXP (op, 0)) == SYMBOL_REF
	       || GET_CODE (XEXP (op, 0)) == LABEL_REF)
	      && GET_CODE (XEXP (op, 1)) == CONST_INT);
    default:
      return 0;
    }
}

/* Return truth value of statement that OP is a symbolic memory
   operand of mode MODE.  */

int
symbolic_memory_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (GET_CODE (op) == SUBREG)
    op = SUBREG_REG (op);
  if (GET_CODE (op) != MEM)
    return 0;
  op = XEXP (op, 0);
  return (GET_CODE (op) == SYMBOL_REF || GET_CODE (op) == CONST
	  || GET_CODE (op) == HIGH || GET_CODE (op) == LABEL_REF);
}

/* Return 1 if the operand is either a register or a memory operand that is
   not symbolic.  */

int
reg_or_nonsymb_mem_operand (op, mode)
    register rtx op;
    enum machine_mode mode;
{
  if (register_operand (op, mode))
    return 1;

  if (memory_operand (op, mode) && ! symbolic_memory_operand (op, mode))
    return 1;

  return 0;
}

/* Return 1 if the operand is either a register, zero, or a memory operand
   that is not symbolic.  */

int
reg_or_0_or_nonsymb_mem_operand (op, mode)
    register rtx op;
    enum machine_mode mode;
{
  if (register_operand (op, mode))
    return 1;

  if (op == CONST0_RTX (mode))
    return 1;

  if (memory_operand (op, mode) && ! symbolic_memory_operand (op, mode))
    return 1;

  return 0;
}

/* Accept any constant that can be moved in one instructions into a
   general register.  */
int
cint_ok_for_move (intval)
     HOST_WIDE_INT intval;
{
  /* OK if ldo, ldil, or zdepi, can be used.  */
  return (VAL_14_BITS_P (intval) || (intval & 0x7ff) == 0
	  || zdepi_cint_p (intval));
}

/* Accept anything that can be moved in one instruction into a general
   register.  */
int
move_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (register_operand (op, mode))
    return 1;

  if (GET_CODE (op) == CONST_INT)
    return cint_ok_for_move (INTVAL (op));

  if (GET_MODE (op) != mode)
    return 0;
  if (GET_CODE (op) == SUBREG)
    op = SUBREG_REG (op);
  if (GET_CODE (op) != MEM)
    return 0;

  op = XEXP (op, 0);
  if (GET_CODE (op) == LO_SUM)
    return (register_operand (XEXP (op, 0), Pmode)
	    && CONSTANT_P (XEXP (op, 1)));
  return memory_address_p (mode, op);
}

/* Accept REG and any CONST_INT that can be moved in one instruction into a
   general register.  */
int
reg_or_cint_move_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (register_operand (op, mode))
    return 1;

  if (GET_CODE (op) == CONST_INT)
    return cint_ok_for_move (INTVAL (op));

  return 0;
}

int
pic_label_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  if (!flag_pic)
    return 0;

  switch (GET_CODE (op))
    {
    case LABEL_REF:
      return 1;
    case CONST:
      op = XEXP (op, 0);
      return (GET_CODE (XEXP (op, 0)) == LABEL_REF
	      && GET_CODE (XEXP (op, 1)) == CONST_INT);
    default:
      return 0;
    }
}

int
fp_reg_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return reg_renumber && FP_REG_P (op);
}



/* Return truth value of whether OP can be used as an operand in a
   three operand arithmetic insn that accepts registers of mode MODE
   or 14-bit signed integers.  */
int
arith_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  || (GET_CODE (op) == CONST_INT && INT_14_BITS (op)));
}

/* Return truth value of whether OP can be used as an operand in a
   three operand arithmetic insn that accepts registers of mode MODE
   or 11-bit signed integers.  */
int
arith11_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  || (GET_CODE (op) == CONST_INT && INT_11_BITS (op)));
}

/* A constant integer suitable for use in a PRE_MODIFY memory
   reference.  */
int
pre_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT
	  && INTVAL (op) >= -0x2000 && INTVAL (op) < 0x10);
}

/* A constant integer suitable for use in a POST_MODIFY memory
   reference.  */
int
post_cint_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT
	  && INTVAL (op) < 0x2000 && INTVAL (op) >= -0x10);
}

int
arith_double_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  || (GET_CODE (op) == CONST_DOUBLE
	      && GET_MODE (op) == mode
	      && VAL_14_BITS_P (CONST_DOUBLE_LOW (op))
	      && (CONST_DOUBLE_HIGH (op) >= 0
		  == ((CONST_DOUBLE_LOW (op) & 0x1000) == 0))));
}

/* Return truth value of whether OP is a integer which fits the
   range constraining immediate operands in three-address insns.  */

int
int5_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT && INT_5_BITS (op));
}

int
uint5_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT && INT_U5_BITS (op));
}

int
int11_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT && INT_11_BITS (op));
}

int
uint32_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
#if HOST_BITS_PER_WIDE_INT > 32
  /* All allowed constants will fit a CONST_INT.  */
  return (GET_CODE (op) == CONST_INT
	  && (INTVAL (op) >= 0 && INTVAL (op) < 0x100000000L));
#else
  return (GET_CODE (op) == CONST_INT
	  || (GET_CODE (op) == CONST_DOUBLE
	      && CONST_DOUBLE_HIGH (op) == 0));
#endif
}

int
arith5_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return register_operand (op, mode) || int5_operand (op, mode);
}

/* True iff zdepi can be used to generate this CONST_INT.  */
int
zdepi_cint_p (x)
     unsigned HOST_WIDE_INT x;
{
  unsigned HOST_WIDE_INT lsb_mask, t;

  /* This might not be obvious, but it's at least fast.
     This function is critical; we don't have the time loops would take.  */
  lsb_mask = x & -x;
  t = ((x >> 4) + lsb_mask) & ~(lsb_mask - 1);
  /* Return true iff t is a power of two.  */
  return ((t & (t - 1)) == 0);
}

/* True iff depi or extru can be used to compute (reg & mask).
   Accept bit pattern like these:
   0....01....1
   1....10....0
   1..10..01..1  */
int
and_mask_p (mask)
     unsigned HOST_WIDE_INT mask;
{
  mask = ~mask;
  mask += mask & -mask;
  return (mask & (mask - 1)) == 0;
}

/* True iff depi or extru can be used to compute (reg & OP).  */
int
and_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (register_operand (op, mode)
	  || (GET_CODE (op) == CONST_INT && and_mask_p (INTVAL (op))));
}

/* True iff depi can be used to compute (reg | MASK).  */
int
ior_mask_p (mask)
     unsigned HOST_WIDE_INT mask;
{
  mask += mask & -mask;
  return (mask & (mask - 1)) == 0;
}

/* True iff depi can be used to compute (reg | OP).  */
int
ior_operand (op, mode)
     rtx op;
     enum machine_mode mode;
{
  return (GET_CODE (op) == CONST_INT && ior_mask_p (INTVAL (op)));
}

int
lhs_lshift_operand (op, mode)
     rtx op;