osprey/kg++fe/gnu/rtl.h

Go to the documentation of this file.

/* Register Transfer Language (RTL) definitions for GNU C-Compiler
   Copyright (C) 1987, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   1999, 2000, 2001, 2002 Free Software Foundation, Inc.

This file is part of GCC.

GCC 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.

GCC 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 GCC; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */

#ifndef GCC_RTL_H
#define GCC_RTL_H

struct function;

#include "machmode.h"

#undef FFS  /* Some systems predefine this symbol; don't let it interfere.  */
#undef FLOAT /* Likewise.  */
#undef ABS /* Likewise.  */
#undef PC /* Likewise.  */

/* Value used by some passes to "recognize" noop moves as valid
 instructions.  */
#define NOOP_MOVE_INSN_CODE INT_MAX

/* Register Transfer Language EXPRESSIONS CODES */

#define RTX_CODE  enum rtx_code
enum rtx_code  {

#define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS)   ENUM ,
#include "rtl.def"    /* rtl expressions are documented here */
#undef DEF_RTL_EXPR

  LAST_AND_UNUSED_RTX_CODE};  /* A convenient way to get a value for
           NUM_RTX_CODE.
           Assumes default enum value assignment.  */

#define NUM_RTX_CODE ((int) LAST_AND_UNUSED_RTX_CODE)
        /* The cast here, saves many elsewhere.  */

extern const unsigned char rtx_length[NUM_RTX_CODE];
#define GET_RTX_LENGTH(CODE)    (rtx_length[(int) (CODE)])

extern const char * const rtx_name[NUM_RTX_CODE];
#define GET_RTX_NAME(CODE)    (rtx_name[(int) (CODE)])

extern const char * const rtx_format[NUM_RTX_CODE];
#define GET_RTX_FORMAT(CODE)    (rtx_format[(int) (CODE)])

extern const char rtx_class[NUM_RTX_CODE];
#define GET_RTX_CLASS(CODE)   (rtx_class[(int) (CODE)])

extern const unsigned char rtx_next[NUM_RTX_CODE];

/* The flags and bitfields of an ADDR_DIFF_VEC.  BASE is the base label
   relative to which the offsets are calculated, as explained in rtl.def.  */
typedef struct
{
  /* Set at the start of shorten_branches - ONLY WHEN OPTIMIZING - : */
  unsigned min_align: 8;
  /* Flags: */
  unsigned base_after_vec: 1; /* BASE is after the ADDR_DIFF_VEC.  */
  unsigned min_after_vec: 1;  /* minimum address target label is
         after the ADDR_DIFF_VEC.  */
  unsigned max_after_vec: 1;  /* maximum address target label is
         after the ADDR_DIFF_VEC.  */
  unsigned min_after_base: 1; /* minimum address target label is
         after BASE.  */
  unsigned max_after_base: 1; /* maximum address target label is
         after BASE.  */
  /* Set by the actual branch shortening process - ONLY WHEN OPTIMIZING - : */
  unsigned offset_unsigned: 1; /* offsets have to be treated as unsigned.  */
  unsigned : 2;
  unsigned scale : 8;
} addr_diff_vec_flags;

/* Structure used to describe the attributes of a MEM.  These are hashed
   so MEMs that the same attributes share a data structure.  This means
   they cannot be modified in place.  If any element is nonzero, it means
   the value of the corresponding attribute is unknown.  */
/* ALIGN and SIZE are the alignment and size of the MEM itself,
   while EXPR can describe a larger underlying object, which might have a
   stricter alignment; OFFSET is the offset of the MEM within that object.  */
typedef struct mem_attrs GTY(())
{
  HOST_WIDE_INT alias;    /* Memory alias set.  */
  tree expr;      /* expr corresponding to MEM.  */
  rtx offset;     /* Offset from start of DECL, as CONST_INT.  */
  rtx size;     /* Size in bytes, as a CONST_INT.  */
  unsigned int align;   /* Alignment of MEM in bits.  */
} mem_attrs;

/* Common union for an element of an rtx.  */

union rtunion_def
{
  HOST_WIDE_INT rtwint;
  int rtint;
  unsigned int rtuint;
  const char *rtstr;
  rtx rtx;
  rtvec rtvec;
  enum machine_mode rttype;
  addr_diff_vec_flags rt_addr_diff_vec_flags;
  struct cselib_val_struct *rt_cselib;
  struct bitmap_head_def *rtbit;
  tree rttree;
  struct basic_block_def *bb;
  mem_attrs *rtmem;
};
typedef union rtunion_def rtunion;

/* RTL expression ("rtx").  */

struct rtx_def GTY((chain_next ("RTX_NEXT (&%h)"), 
        chain_prev ("RTX_PREV (&%h)")))
{
  /* The kind of expression this is.  */
  ENUM_BITFIELD(rtx_code) code: 16;

  /* The kind of value the expression has.  */
  ENUM_BITFIELD(machine_mode) mode : 8;

  /* 1 in a MEM if we should keep the alias set for this mem unchanged
     when we access a component.
     1 in a CALL_INSN if it is a sibling call.
     1 in a SET that is for a return.
     In a CODE_LABEL, part of the two-bit alternate entry field.  */
  unsigned int jump : 1;
  /* In a CODE_LABEL, part of the two-bit alternate entry field.
     1 in a MEM if it cannot trap.  */
  unsigned int call : 1;
  /* 1 in a REG, MEM, or CONCAT if the value is set at most once, anywhere.
     1 in a SUBREG if it references an unsigned object whose mode has been
     from a promoted to a wider mode.
     1 in a SYMBOL_REF if it addresses something in the per-function
     constants pool.
     1 in a CALL_INSN, NOTE, or EXPR_LIST for a const or pure call.
     1 in a JUMP_INSN, CALL_INSN, or INSN of an annulling branch.  */
  unsigned int unchanging : 1;
  /* 1 in a MEM or ASM_OPERANDS expression if the memory reference is volatile.
     1 in an INSN, CALL_INSN, JUMP_INSN, CODE_LABEL, BARRIER, or NOTE
     if it has been deleted.
     1 in a REG expression if corresponds to a variable declared by the user,
     0 for an internally generated temporary.
     1 in a SUBREG with a negative value.
     1 in a LABEL_REF or in a REG_LABEL note for a non-local label.
     In a SYMBOL_REF, this flag is used for machine-specific purposes.  */
  unsigned int volatil : 1;
  /* 1 in a MEM referring to a field of an aggregate.
     0 if the MEM was a variable or the result of a * operator in C;
     1 if it was the result of a . or -> operator (on a struct) in C.
     1 in a REG if the register is used only in exit code a loop.
     1 in a SUBREG expression if was generated from a variable with a
     promoted mode.
     1 in a CODE_LABEL if the label is used for nonlocal gotos
     and must not be deleted even if its count is zero.
     1 in a LABEL_REF if this is a reference to a label outside the
     current loop.
     1 in an INSN, JUMP_INSN or CALL_INSN if this insn must be scheduled
     together with the preceding insn.  Valid only within sched.
     1 in an INSN, JUMP_INSN, or CALL_INSN if insn is in a delay slot and
     from the target of a branch.  Valid from reorg until end of compilation;
     cleared before used.
     1 in an INSN or related rtx if this insn is dead code.  Valid only during
     dead-code elimination phase; cleared before use.  */
  unsigned int in_struct : 1;
  /* At the end of RTL generation, 1 if this rtx is used.  This is used for
     copying shared structure.  See `unshare_all_rtl'.
     In a REG, this is not needed for that purpose, and used instead
     in `leaf_renumber_regs_insn'.
     1 in a SYMBOL_REF, means that emit_library_call
     has used it as the function.  */
  unsigned int used : 1;
  /* Nonzero if this rtx came from procedure integration.
     1 in a REG or PARALLEL means this rtx refers to the return value
     of the current function.
     1 in a SYMBOL_REF if the symbol is weak.  */
  unsigned integrated : 1;
  /* 1 in an INSN or a SET if this rtx is related to the call frame,
     either changing how we compute the frame address or saving and
     restoring registers in the prologue and epilogue.
     1 in a MEM if the MEM refers to a scalar, rather than a member of
     an aggregate.
     1 in a REG if the register is a pointer.
     1 in a SYMBOL_REF if it addresses something in the per-function
     constant string pool.  */
  unsigned frame_related : 1;

  /* The first element of the operands of this rtx.
     The number of operands and their types are controlled
     by the `code' field, according to rtl.def.  */
  rtunion GTY ((special ("rtx_def"),
    desc ("GET_CODE (&%0)"))) fld[1];
};

#define NULL_RTX (rtx) 0

/* The "next" and "previous" RTX, relative to this one.  */

#define RTX_NEXT(X) (rtx_next[GET_CODE (X)] == 0 ? NULL     \
         : *(rtx *)(((char *)X) + rtx_next[GET_CODE (X)]))

/* FIXME: the "NEXT_INSN (PREV_INSN (X)) == X" condition shouldn't be needed.
 */
#define RTX_PREV(X) ((GET_CODE (X) == INSN              \
                      || GET_CODE (X) == CALL_INSN      \
                      || GET_CODE (X) == JUMP_INSN      \
                      || GET_CODE (X) == NOTE           \
                      || GET_CODE (X) == BARRIER        \
                      || GET_CODE (X) == CODE_LABEL)    \
                     && PREV_INSN (X) != NULL           \
                     && NEXT_INSN (PREV_INSN (X)) == X  \
                     ? PREV_INSN (X) : NULL)

/* Define macros to access the `code' field of the rtx.  */

#define GET_CODE(RTX)     ((enum rtx_code) (RTX)->code)
#define PUT_CODE(RTX, CODE) ((RTX)->code = (ENUM_BITFIELD(rtx_code)) (CODE))

#define GET_MODE(RTX)     ((enum machine_mode) (RTX)->mode)
#define PUT_MODE(RTX, MODE) ((RTX)->mode = (ENUM_BITFIELD(machine_mode)) (MODE))

/* RTL vector.  These appear inside RTX's when there is a need
   for a variable number of things.  The principle use is inside
   PARALLEL expressions.  */

struct rtvec_def GTY(()) {
  int num_elem;   /* number of elements */
  rtx GTY ((length ("%h.num_elem"))) elem[1];
};

#define NULL_RTVEC (rtvec) 0

#define GET_NUM_ELEM(RTVEC)   ((RTVEC)->num_elem)
#define PUT_NUM_ELEM(RTVEC, NUM)  ((RTVEC)->num_elem = (NUM))

/* Predicate yielding nonzero iff X is an rtl for a register.  */
#define REG_P(X) (GET_CODE (X) == REG)

/* Predicate yielding nonzero iff X is a label insn.  */
#define LABEL_P(X) (GET_CODE (X) == CODE_LABEL)

/* Predicate yielding nonzero iff X is a jump insn.  */
#define JUMP_P(X) (GET_CODE (X) == JUMP_INSN)

/* Predicate yielding nonzero iff X is a note insn.  */
#define NOTE_P(X) (GET_CODE (X) == NOTE)

/* Predicate yielding nonzero iff X is a barrier insn.  */
#define BARRIER_P(X) (GET_CODE (X) == BARRIER)

/* Predicate yielding nonzero iff X is cc0.  */
#ifdef HAVE_cc0
#define CC0_P(X) ((X) == cc0_rtx)
#else
#define CC0_P(X) 0
#endif

/* Predicate yielding nonzero iff X is a data for a jump table.  */
#define JUMP_TABLE_DATA_P(INSN) \
  (JUMP_P (INSN) && (GET_CODE (PATTERN (INSN)) == ADDR_VEC || \
         GET_CODE (PATTERN (INSN)) == ADDR_DIFF_VEC))

/* 1 if X is a constant value that is an integer.  */

#define CONSTANT_P(X)   \
  (GET_CODE (X) == LABEL_REF || GET_CODE (X) == SYMBOL_REF    \
   || GET_CODE (X) == CONST_INT || GET_CODE (X) == CONST_DOUBLE   \
   || GET_CODE (X) == CONST || GET_CODE (X) == HIGH     \
   || GET_CODE (X) == CONST_VECTOR                                  \
   || GET_CODE (X) == CONSTANT_P_RTX)

/* General accessor macros for accessing the fields of an rtx.  */

#if defined ENABLE_RTL_CHECKING && (GCC_VERSION >= 2007)
/* The bit with a star outside the statement expr and an & inside is
   so that N can be evaluated only once.  */
#define RTL_CHECK1(RTX, N, C1) __extension__        \
(*({ rtx const _rtx = (RTX); const int _n = (N);      \
     const enum rtx_code _code = GET_CODE (_rtx);     \
     if (_n < 0 || _n >= GET_RTX_LENGTH (_code))      \
       rtl_check_failed_bounds (_rtx, _n, __FILE__, __LINE__,   \
        __FUNCTION__);        \
     if (GET_RTX_FORMAT(_code)[_n] != C1)       \
       rtl_check_failed_type1 (_rtx, _n, C1, __FILE__, __LINE__,  \
             __FUNCTION__);       \
     &_rtx->fld[_n]; }))

#define RTL_CHECK2(RTX, N, C1, C2) __extension__      \
(*({ rtx const _rtx = (RTX); const int _n = (N);      \
     const enum rtx_code _code = GET_CODE (_rtx);     \
     if (_n < 0 || _n >= GET_RTX_LENGTH (_code))      \
       rtl_check_failed_bounds (_rtx, _n, __FILE__, __LINE__,   \
        __FUNCTION__);        \
     if (GET_RTX_FORMAT(_code)[_n] != C1        \
   && GET_RTX_FORMAT(_code)[_n] != C2)        \
       rtl_check_failed_type2 (_rtx, _n, C1, C2, __FILE__, __LINE__,  \
             __FUNCTION__);       \
     &_rtx->fld[_n]; }))

#define RTL_CHECKC1(RTX, N, C) __extension__        \
(*({ rtx const _rtx = (RTX); const int _n = (N);      \
     if (GET_CODE (_rtx) != (C))          \
       rtl_check_failed_code1 (_rtx, (C), __FILE__, __LINE__,   \
             __FUNCTION__);       \
     &_rtx->fld[_n]; }))

#define RTL_CHECKC2(RTX, N, C1, C2) __extension__     \
(*({ rtx const _rtx = (RTX); const int _n = (N);      \
     const enum rtx_code _code = GET_CODE (_rtx);     \
     if (_code != (C1) && _code != (C2))        \
       rtl_check_failed_code2 (_rtx, (C1), (C2), __FILE__, __LINE__,  \
             __FUNCTION__); \
     &_rtx->fld[_n]; }))

#define RTVEC_ELT(RTVEC, I) __extension__       \
(*({ rtvec const _rtvec = (RTVEC); const int _i = (I);      \
     if (_i < 0 || _i >= GET_NUM_ELEM (_rtvec))       \
       rtvec_check_failed_bounds (_rtvec, _i, __FILE__, __LINE__, \
          __FUNCTION__);      \
     &_rtvec->elem[_i]; }))

extern void rtl_check_failed_bounds PARAMS ((rtx, int,
             const char *, int, const char *))
    ATTRIBUTE_NORETURN;
extern void rtl_check_failed_type1 PARAMS ((rtx, int, int,
            const char *, int, const char *))
    ATTRIBUTE_NORETURN;
extern void rtl_check_failed_type2 PARAMS ((rtx, int, int, int,
            const char *, int, const char *))
    ATTRIBUTE_NORETURN;
extern void rtl_check_failed_code1 PARAMS ((rtx, enum rtx_code,
            const char *, int, const char *))
    ATTRIBUTE_NORETURN;
extern void rtl_check_failed_code2 PARAMS ((rtx, enum rtx_code, enum rtx_code,
            const char *, int, const char *))
    ATTRIBUTE_NORETURN;
extern void rtvec_check_failed_bounds PARAMS ((rtvec, int,
               const char *, int, const char *))
    ATTRIBUTE_NORETURN;

#else   /* not ENABLE_RTL_CHECKING */

#define RTL_CHECK1(RTX, N, C1)      ((RTX)->fld[N])
#define RTL_CHECK2(RTX, N, C1, C2)  ((RTX)->fld[N])
#define RTL_CHECKC1(RTX, N, C)      ((RTX)->fld[N])
#define RTL_CHECKC2(RTX, N, C1, C2) ((RTX)->fld[N])
#define RTVEC_ELT(RTVEC, I)     ((RTVEC)->elem[I])

#endif

/* General accessor macros for accessing the flags of an rtx.  */

/* Access an individual rtx flag, with no checking of any kind.  */
#define RTX_FLAG(RTX, FLAG) ((RTX)->FLAG)

#if defined ENABLE_RTL_FLAG_CHECKING && (GCC_VERSION >= 2007)
#define RTL_FLAG_CHECK1(NAME, RTX, C1) __extension__      \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1)            \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                 __FUNCTION__);       \
   _rtx; })

#define RTL_FLAG_CHECK2(NAME, RTX, C1, C2) __extension__    \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2)      \
     rtl_check_failed_flag  (NAME,_rtx, __FILE__, __LINE__,   \
                  __FUNCTION__);        \
   _rtx; })

#define RTL_FLAG_CHECK3(NAME, RTX, C1, C2, C3) __extension__    \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2       \
       && GET_CODE(_rtx) != C3)           \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                 __FUNCTION__);       \
   _rtx; })

#define RTL_FLAG_CHECK4(NAME, RTX, C1, C2, C3, C4) __extension__  \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2     \
       && GET_CODE(_rtx) != C3 && GET_CODE(_rtx) != C4)     \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                  __FUNCTION__);        \
   _rtx; })

#define RTL_FLAG_CHECK5(NAME, RTX, C1, C2, C3, C4, C5) __extension__  \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2     \
       && GET_CODE(_rtx) != C3 && GET_CODE(_rtx) != C4      \
       && GET_CODE(_rtx) != C5)           \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                 __FUNCTION__);       \
   _rtx; })

#define RTL_FLAG_CHECK6(NAME, RTX, C1, C2, C3, C4, C5, C6)    \
  __extension__               \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2     \
       && GET_CODE(_rtx) != C3 && GET_CODE(_rtx) != C4      \
       && GET_CODE(_rtx) != C5 && GET_CODE(_rtx) != C6)     \
     rtl_check_failed_flag  (NAME,_rtx, __FILE__, __LINE__,   \
                 __FUNCTION__);       \
   _rtx; })

#define RTL_FLAG_CHECK7(NAME, RTX, C1, C2, C3, C4, C5, C6, C7)    \
  __extension__               \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2     \
       && GET_CODE(_rtx) != C3 && GET_CODE(_rtx) != C4      \
       && GET_CODE(_rtx) != C5 && GET_CODE(_rtx) != C6      \
       && GET_CODE(_rtx) != C7)           \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                 __FUNCTION__);       \
   _rtx; })

#define RTL_FLAG_CHECK8(NAME, RTX, C1, C2, C3, C4, C5, C6, C7, C8)  \
  __extension__               \
({ rtx const _rtx = (RTX);            \
   if (GET_CODE(_rtx) != C1 && GET_CODE(_rtx) != C2     \
       && GET_CODE(_rtx) != C3 && GET_CODE(_rtx) != C4      \
       && GET_CODE(_rtx) != C5 && GET_CODE(_rtx) != C6      \
       && GET_CODE(_rtx) != C7 && GET_CODE(_rtx) != C8)     \
     rtl_check_failed_flag  (NAME, _rtx, __FILE__, __LINE__,    \
                 __FUNCTION__);       \
   _rtx; })

extern void rtl_check_failed_flag PARAMS ((const char *, rtx, const char *,
                   int, const char *))
    ATTRIBUTE_NORETURN
    ;

#else /* not ENABLE_RTL_FLAG_CHECKING */

#define RTL_FLAG_CHECK1(NAME, RTX, C1)          (RTX)
#define RTL_FLAG_CHECK2(NAME, RTX, C1, C2)        (RTX)
#define RTL_FLAG_CHECK3(NAME, RTX, C1, C2, C3)        (RTX)
#define RTL_FLAG_CHECK4(NAME, RTX, C1, C2, C3, C4)      (RTX)
#define RTL_FLAG_CHECK5(NAME, RTX, C1, C2, C3, C4, C5)      (RTX)
#define RTL_FLAG_CHECK6(NAME, RTX, C1, C2, C3, C4, C5, C6)    (RTX)
#define RTL_FLAG_CHECK7(NAME, RTX, C1, C2, C3, C4, C5, C6, C7)    (RTX)
#define RTL_FLAG_CHECK8(NAME, RTX, C1, C2, C3, C4, C5, C6, C7, C8)  (RTX)
#endif

#define CLEAR_RTX_FLAGS(RTX)  \
do {        \
  rtx const _rtx = (RTX); \
  _rtx->call = 0;   \
  _rtx->frame_related = 0;  \
  _rtx->in_struct = 0;    \
  _rtx->integrated = 0;   \
  _rtx->jump = 0;   \
  _rtx->unchanging = 0;   \
  _rtx->used = 0;   \
  _rtx->volatil = 0;    \
} while (0)

#define XWINT(RTX, N) (RTL_CHECK1 (RTX, N, 'w').rtwint)
#define XINT(RTX, N)  (RTL_CHECK2 (RTX, N, 'i', 'n').rtint)
#define XSTR(RTX, N)  (RTL_CHECK2 (RTX, N, 's', 'S').rtstr)
#define XEXP(RTX, N)  (RTL_CHECK2 (RTX, N, 'e', 'u').rtx)
#define XVEC(RTX, N)  (RTL_CHECK2 (RTX, N, 'E', 'V').rtvec)
#define XMODE(RTX, N) (RTL_CHECK1 (RTX, N, 'M').rttype)
#define XBITMAP(RTX, N) (RTL_CHECK1 (RTX, N, 'b').rtbit)
#define XTREE(RTX, N)   (RTL_CHECK1 (RTX, N, 't').rttree)
#define XBBDEF(RTX, N)  (RTL_CHECK1 (RTX, N, 'B').bb)
#define XTMPL(RTX, N) (RTL_CHECK1 (RTX, N, 'T').rtstr)

#define XVECEXP(RTX, N, M)  RTVEC_ELT (XVEC (RTX, N), M)
#define XVECLEN(RTX, N)   GET_NUM_ELEM (XVEC (RTX, N))

/* These are like XWINT, etc. except that they expect a '0' field instead
   of the normal type code.  */

#define X0WINT(RTX, N)     (RTL_CHECK1 (RTX, N, '0').rtwint)
#define X0INT(RTX, N)    (RTL_CHECK1 (RTX, N, '0').rtint)
#define X0UINT(RTX, N)     (RTL_CHECK1 (RTX, N, '0').rtuint)
#define X0STR(RTX, N)    (RTL_CHECK1 (RTX, N, '0').rtstr)
#define X0EXP(RTX, N)    (RTL_CHECK1 (RTX, N, '0').rtx)
#define X0VEC(RTX, N)    (RTL_CHECK1 (RTX, N, '0').rtvec)
#define X0MODE(RTX, N)     (RTL_CHECK1 (RTX, N, '0').rttype)
#define X0BITMAP(RTX, N)   (RTL_CHECK1 (RTX, N, '0').rtbit)
#define X0TREE(RTX, N)     (RTL_CHECK1 (RTX, N, '0').rttree)
#define X0BBDEF(RTX, N)    (RTL_CHECK1 (RTX, N, '0').bb)
#define X0ADVFLAGS(RTX, N) (RTL_CHECK1 (RTX, N, '0').rt_addr_diff_vec_flags)
#define X0CSELIB(RTX, N)   (RTL_CHECK1 (RTX, N, '0').rt_cselib)
#define X0MEMATTR(RTX, N)  (RTL_CHECK1 (RTX, N, '0').rtmem)

#define XCWINT(RTX, N, C)     (RTL_CHECKC1 (RTX, N, C).rtwint)
#define XCINT(RTX, N, C)      (RTL_CHECKC1 (RTX, N, C).rtint)
#define XCUINT(RTX, N, C)     (RTL_CHECKC1 (RTX, N, C).rtuint)
#define XCSTR(RTX, N, C)      (RTL_CHECKC1 (RTX, N, C).rtstr)
#define XCEXP(RTX, N, C)      (RTL_CHECKC1 (RTX, N, C).rtx)
#define XCVEC(RTX, N, C)      (RTL_CHECKC1 (RTX, N, C).rtvec)
#define XCMODE(RTX, N, C)     (RTL_CHECKC1 (RTX, N, C).rttype)
#define XCBITMAP(RTX, N, C)   (RTL_CHECKC1 (RTX, N, C).rtbit)
#define XCTREE(RTX, N, C)     (RTL_CHECKC1 (RTX, N, C).rttree)
#define XCBBDEF(RTX, N, C)    (RTL_CHECKC1 (RTX, N, C).bb)
#define XCADVFLAGS(RTX, N, C) (RTL_CHECKC1 (RTX, N, C).rt_addr_diff_vec_flags)
#define XCCSELIB(RTX, N, C)   (RTL_CHECKC1 (RTX, N, C).rt_cselib)

#define XCVECEXP(RTX, N, M, C)  RTVEC_ELT (XCVEC (RTX, N, C), M)
#define XCVECLEN(RTX, N, C) GET_NUM_ELEM (XCVEC (RTX, N, C))

#define XC2EXP(RTX, N, C1, C2)      (RTL_CHECKC2 (RTX, N, C1, C2).rtx)

/* ACCESS MACROS for particular fields of insns.  */

/* Determines whether X is an insn.  */
#define INSN_P(X)       (GET_RTX_CLASS (GET_CODE(X)) == 'i')

/* Holds a unique number for each insn.
   These are not necessarily sequentially increasing.  */
#define INSN_UID(INSN)  XINT (INSN, 0)

/* Chain insns together in sequence.  */
#define PREV_INSN(INSN) XEXP (INSN, 1)
#define NEXT_INSN(INSN) XEXP (INSN, 2)

#define BLOCK_FOR_INSN(INSN) XBBDEF (INSN, 3)
#define INSN_SCOPE(INSN) XTREE (INSN, 4)
/* The body of an insn.  */
#define PATTERN(INSN) XEXP (INSN, 5)

/* Code number of instruction, from when it was recognized.
   -1 means this instruction has not been recognized yet.  */
#define INSN_CODE(INSN) XINT (INSN, 6)

/* Set up in flow.c; empty before then.
   Holds a chain of INSN_LIST rtx's whose first operands point at
   previous insns with direct data-flow connections to this one.
   That means that those insns set variables whose next use is in this insn.
   They are always in the same basic block as this insn.  */
#define LOG_LINKS(INSN) XEXP(INSN, 7)

#define RTX_INTEGRATED_P(RTX)           \
  (RTL_FLAG_CHECK8("RTX_INTEGRATED_P", (RTX), INSN, CALL_INSN,    \
       JUMP_INSN, INSN_LIST, BARRIER, CODE_LABEL, CONST,  \
       NOTE)->integrated)
#define RTX_UNCHANGING_P(RTX)           \
  (RTL_FLAG_CHECK3("RTX_UNCHANGING_P", (RTX), REG, MEM, CONCAT)->unchanging)
#define RTX_FRAME_RELATED_P(RTX)          \
  (RTL_FLAG_CHECK5("RTX_FRAME_RELATED_P", (RTX), INSN, CALL_INSN, \
       JUMP_INSN, BARRIER, SET)->frame_related)

/* 1 if RTX is an insn that has been deleted.  */
#define INSN_DELETED_P(RTX)           \
  (RTL_FLAG_CHECK6("INSN_DELETED_P", (RTX), INSN, CALL_INSN, JUMP_INSN, \
       CODE_LABEL, BARRIER, NOTE)->volatil)

/* 1 if RTX is a call to a const or pure function.  */
#define CONST_OR_PURE_CALL_P(RTX)         \
  (RTL_FLAG_CHECK3("CONST_OR_PURE_CALL_P", (RTX), CALL_INSN, NOTE,  \
       EXPR_LIST)->unchanging)

/* 1 if RTX is a call_insn for a sibling call.  */
#define SIBLING_CALL_P(RTX)           \
  (RTL_FLAG_CHECK1("SIBLING_CALL_P", (RTX), CALL_INSN)->jump)

/* 1 if RTX is a jump_insn, call_insn, or insn that is an annulling branch.  */
#define INSN_ANNULLED_BRANCH_P(RTX)         \
  (RTL_FLAG_CHECK3("INSN_ANNULLED_BRANCH_P", (RTX), JUMP_INSN, CALL_INSN, INSN)->unchanging)

/* 1 if RTX is an insn that is dead code.  Valid only for dead-code
   elimination phase.  */
#define INSN_DEAD_CODE_P(RTX)           \
  (RTL_FLAG_CHECK1("INSN_DEAD_CODE_P", (RTX), INSN)->in_struct)

/* 1 if RTX is an insn in a delay slot and is from the target of the branch.
   If the branch insn has INSN_ANNULLED_BRANCH_P set, this insn should only be
   executed if the branch is taken.  For annulled branches with this bit
   clear, the insn should be executed only if the branch is not taken.  */
#define INSN_FROM_TARGET_P(RTX)           \
  (RTL_FLAG_CHECK3("INSN_FROM_TARGET_P", (RTX), INSN, JUMP_INSN, CALL_INSN)->in_struct)

#define ADDR_DIFF_VEC_FLAGS(RTX) X0ADVFLAGS(RTX, 4)

#define CSELIB_VAL_PTR(RTX) X0CSELIB(RTX, 0)

/* Holds a list of notes on what this insn does to various REGs.
   It is a chain of EXPR_LIST rtx's, where the second operand is the
   chain pointer and the first operand is the REG being described.
   The mode field of the EXPR_LIST contains not a real machine mode
   but a value from enum reg_note.  */

#define REG_NOTES(INSN) XEXP(INSN, 8)

/* Don't forget to change reg_note_name in rtl.c.  */
enum reg_note
{
  /* The value in REG dies in this insn (i.e., it is not needed past
     this insn).  If REG is set in this insn, the REG_DEAD note may,
     but need not, be omitted.  */
  REG_DEAD = 1,

  /* The REG is autoincremented or autodecremented.  */
  REG_INC,

  /* Describes the insn as a whole; it says that the insn sets a register
     to a constant value or to be equivalent to a memory address.  If the
     register is spilled to the stack then the constant value should be
     substituted for it.  The contents of the REG_EQUIV is the constant
     value or memory address, which may be different from the source of
     the SET although it has the same value.  A REG_EQUIV note may also
     appear on an insn which copies a register parameter to a pseudo-register,
     if there is a memory address which could be used to hold that
     pseudo-register throughout the function.  */
  REG_EQUIV,

  /* Like REG_EQUIV except that the destination is only momentarily equal
     to the specified rtx.  Therefore, it cannot be used for substitution;
     but it can be used for cse.  */
  REG_EQUAL,

  /* The register set in this insn held 0 before the insn.  The contents of
     the note is the insn that stored the 0.  If that insn is deleted or
     patched to a NOTE, the REG_WAS_0 is inoperative.  The REG_WAS_0 note
     is actually an INSN_LIST, not an EXPR_LIST.  */
  REG_WAS_0,

  /* This insn copies the return-value of a library call out of the hard reg
     for return values.  This note is actually an INSN_LIST and it points to
     the first insn involved in setting up arguments for the call.  flow.c
     uses this to delete the entire library call when its result is dead.  */
  REG_RETVAL,

  /* The inverse of REG_RETVAL: it goes on the first insn of the library call
     and points at the one that has the REG_RETVAL.  This note is also an
     INSN_LIST.  */
  REG_LIBCALL,

  /* The register is always nonnegative during the containing loop.  This is
     used in branches so that decrement and branch instructions terminating
     on zero can be matched.  There must be an insn pattern in the md file
     named `decrement_and_branch_until_zero' or else this will never be added
     to any instructions.  */
  REG_NONNEG,

  /* There is no conflict *after this insn* between the register in the note
     and the destination of this insn.  */
  REG_NO_CONFLICT,

  /* Identifies a register set in this insn and never used.  */
  REG_UNUSED,

  /* REG_CC_SETTER and REG_CC_USER link a pair of insns that set and use CC0,
     respectively.  Normally, these are required to be consecutive insns, but
     we permit putting a cc0-setting insn in the delay slot of a branch as
     long as only one copy of the insn exists.  In that case, these notes
     point from one to the other to allow code generation to determine what
     any require information and to properly update CC_STATUS.  These notes
     are INSN_LISTs.  */
  REG_CC_SETTER, REG_CC_USER,

  /* Points to a CODE_LABEL.  Used by non-JUMP_INSNs to say that the
     CODE_LABEL contained in the REG_LABEL note is used by the insn. 
     This note is an INSN_LIST.  */
  REG_LABEL,

  /* REG_DEP_ANTI and REG_DEP_OUTPUT are used in LOG_LINKS to represent
     write-after-read and write-after-write dependencies respectively.
     Data dependencies, which are the only type of LOG_LINK created by
     flow, are represented by a 0 reg note kind.  */
  REG_DEP_ANTI, REG_DEP_OUTPUT,

  /* REG_BR_PROB is attached to JUMP_INSNs and CALL_INSNs.
     It has an integer value.  For jumps, it is the probability that this is a
     taken branch.  For calls, it is the probability that this call won't
     return.  */
  REG_BR_PROB,

  /* Attached to a call insn; indicates that the call is malloc-like and
     that the pointer returned cannot alias anything else.  */
  REG_NOALIAS,

  /* Used to optimize rtl generated by dynamic stack allocations for targets
     where SETJMP_VIA_SAVE_AREA is true.  */
  REG_SAVE_AREA,

  /* REG_BR_PRED is attached to JUMP_INSNs and CALL_INSNSs.  It contains
     CONCAT of two integer value.  First specifies the branch predictor
     that added the note, second specifies the predicted hitrate of branch
     in the same format as REG_BR_PROB note uses.  */
  REG_BR_PRED,

  /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
     for DWARF to interpret what they imply.  The attached rtx is used
     instead of intuition.  */
  REG_FRAME_RELATED_EXPR,

  /* Indicates that REG holds the exception context for the function.
     This context is shared by inline functions, so the code to acquire
     the real exception context is delayed until after inlining.  */
  REG_EH_CONTEXT,

  /* Indicates what exception region an INSN belongs in.  This is used to
     indicate what region to which a call may throw.  REGION 0 indicates
     that a call cannot throw at all.  REGION -1 indicates that it cannot
     throw, nor will it execute a non-local goto.  */
  REG_EH_REGION,

  /* Used by haifa-sched to save NOTE_INSN notes across scheduling.  */
  REG_SAVE_NOTE,

  /* Indicates that this insn (which is part of the prologue) computes
     a value which might not be used later, and if so it's OK to delete
     the insn.  Normally, deleting any insn in the prologue is an error. 
     At present the parameter is unused and set to (const_int 0).  */
  REG_MAYBE_DEAD,

  /* Indicates that a call does not return.  */
  REG_NORETURN,

  /* Indicates that an indirect jump is a non-local goto instead of a 
     computed goto.  */
  REG_NON_LOCAL_GOTO,

  /* This kind of note is generated at each to `setjmp',
     and similar functions that can return twice.  */
  REG_SETJMP,

  /* Indicate calls that always returns.  */
  REG_ALWAYS_RETURN,

  /* Indicate that the memory load references a vtable.  The expression
     is of the form (plus (symbol_ref vtable_sym) (const_int offset)).  */
  REG_VTABLE_REF
};

/* The base value for branch probability notes.  */
#define REG_BR_PROB_BASE  10000

/* Define macros to extract and insert the reg-note kind in an EXPR_LIST.  */
#define REG_NOTE_KIND(LINK) ((enum reg_note) GET_MODE (LINK))
#define PUT_REG_NOTE_KIND(LINK, KIND) \
  PUT_MODE (LINK, (enum machine_mode) (KIND))

/* Names for REG_NOTE's in EXPR_LIST insn's.  */

extern const char * const reg_note_name[];
#define GET_REG_NOTE_NAME(MODE) (reg_note_name[(int) (MODE)])

/* This field is only present on CALL_INSNs.  It holds a chain of EXPR_LIST of
   USE and CLOBBER expressions.
     USE expressions list the registers filled with arguments that
   are passed to the function.
     CLOBBER expressions document the registers explicitly clobbered
   by this CALL_INSN.
     Pseudo registers can not be mentioned in this list.  */
#define CALL_INSN_FUNCTION_USAGE(INSN)  XEXP(INSN, 9)

/* The label-number of a code-label.  The assembler label
   is made from `L' and the label-number printed in decimal.
   Label numbers are unique in a compilation.  */
#define CODE_LABEL_NUMBER(INSN) XINT (INSN, 6)

#define LINE_NUMBER NOTE

/* In a NOTE that is a line number, this is a string for the file name that the
   line is in.  We use the same field to record block numbers temporarily in
   NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes.  (We avoid lots of casts
   between ints and pointers if we use a different macro for the block number.)
   */

#define NOTE_SOURCE_FILE(INSN)  XCSTR (INSN, 4, NOTE)
#define NOTE_BLOCK(INSN)  XCTREE (INSN, 4, NOTE)
#define NOTE_EH_HANDLER(INSN) XCINT (INSN, 4, NOTE)
#define NOTE_BASIC_BLOCK(INSN)  XCBBDEF (INSN, 4, NOTE)
#define NOTE_EXPECTED_VALUE(INSN) XCEXP (INSN, 4, NOTE)
#define NOTE_PREDICTION(INSN)   XCINT (INSN, 4, NOTE)
#define NOTE_PRECONDITIONED(INSN)   XCINT (INSN, 4, NOTE)

/* In a NOTE that is a line number, this is the line number.
   Other kinds of NOTEs are identified by negative numbers here.  */
#define NOTE_LINE_NUMBER(INSN) XCINT (INSN, 5, NOTE)

/* Nonzero if INSN is a note marking the beginning of a basic block.  */
#define NOTE_INSN_BASIC_BLOCK_P(INSN)       \
  (GET_CODE (INSN) == NOTE        \
   && NOTE_LINE_NUMBER (INSN) == NOTE_INSN_BASIC_BLOCK)

/* Algorithm and flags for prediction.  */
#define NOTE_PREDICTION_ALG(INSN)   (XCINT(INSN, 4, NOTE)>>8)
#define NOTE_PREDICTION_FLAGS(INSN) (XCINT(INSN, 4, NOTE)&0xff)
#define NOTE_PREDICT(ALG,FLAGS)     ((ALG<<8)+(FLAGS))

/* Codes that appear in the NOTE_LINE_NUMBER field
   for kinds of notes that are not line numbers.

   Notice that we do not try to use zero here for any of
   the special note codes because sometimes the source line
   actually can be zero!  This happens (for example) when we
   are generating code for the per-translation-unit constructor
   and destructor routines for some C++ translation unit.

   If you should change any of the following values, or if you
   should add a new value here, don't forget to change the
   note_insn_name array in rtl.c.  */

enum insn_note
{
  /* Keep all of these numbers negative.  Adjust as needed.  */
  NOTE_INSN_BIAS = -100,

  /* This note is used to get rid of an insn
     when it isn't safe to patch the insn out of the chain.  */
  NOTE_INSN_DELETED,

  /* These are used to mark the beginning and end of a lexical block.
     See NOTE_BLOCK, identify_blocks and reorder_blocks.  */
  NOTE_INSN_BLOCK_BEG,
  NOTE_INSN_BLOCK_END,

  /* These mark the extremes of a loop.  */
  NOTE_INSN_LOOP_BEG,
  NOTE_INSN_LOOP_END,

  /* Generated at the place in a loop that `continue' jumps to.  */
  NOTE_INSN_LOOP_CONT,
  /* Generated at the start of a duplicated exit test.  */
  NOTE_INSN_LOOP_VTOP,

  /* Generated at the end of a conditional at the top of the loop.
     This is used to perform a lame form of loop rotation in lieu
     of actually understanding the loop structure.  The note is
     discarded after rotation is complete.  */
  NOTE_INSN_LOOP_END_TOP_COND,

  /* This kind of note is generated at the end of the function body,
     just before the return insn or return label.  In an optimizing
     compilation it is deleted by the first jump optimization, after
     enabling that optimizer to determine whether control can fall
     off the end of the function body without a return statement.  */
  NOTE_INSN_FUNCTION_END,

  /* This marks the point immediately after the last prologue insn.  */
  NOTE_INSN_PROLOGUE_END,

  /* This marks the point immediately prior to the first epilogue insn.  */
  NOTE_INSN_EPILOGUE_BEG,

  /* Generated in place of user-declared labels when they are deleted.  */
  NOTE_INSN_DELETED_LABEL,

  /* This note indicates the start of the real body of the function,
     i.e. the point just after all of the parms have been moved into
     their homes, etc.  */
  NOTE_INSN_FUNCTION_BEG,

  /* These note where exception handling regions begin and end. 
     Uses NOTE_EH_HANDLER to identify the region in question.  */
  NOTE_INSN_EH_REGION_BEG,
  NOTE_INSN_EH_REGION_END,

  /* Generated whenever a duplicate line number note is output.  For example,
     one is output after the end of an inline function, in order to prevent
     the line containing the inline call from being counted twice in gcov.  */
  NOTE_INSN_REPEATED_LINE_NUMBER,

  /* Record the struct for the following basic block.  Uses NOTE_BASIC_BLOCK.  */
  NOTE_INSN_BASIC_BLOCK,

  /* Record the expected value of a register at a location.  Uses
     NOTE_EXPECTED_VALUE; stored as (eq (reg) (const_int)).  */
  NOTE_INSN_EXPECTED_VALUE,

  /* Record a prediction.  Uses NOTE_PREDICTION.  */
  NOTE_INSN_PREDICTION,

  NOTE_INSN_MAX
};

/* Names for NOTE insn's other than line numbers.  */

extern const char * const note_insn_name[NOTE_INSN_MAX - NOTE_INSN_BIAS];
#define GET_NOTE_INSN_NAME(NOTE_CODE) \
  (note_insn_name[(NOTE_CODE) - (int) NOTE_INSN_BIAS])

/* The name of a label, in case it corresponds to an explicit label
   in the input source code.  */
#define LABEL_NAME(RTX) XCSTR (RTX, 7, CODE_LABEL)

/* In jump.c, each label contains a count of the number
   of LABEL_REFs that point at it, so unused labels can be deleted.  */
#define LABEL_NUSES(RTX) XCINT (RTX, 4, CODE_LABEL)

/* Labels carry a two-bit field composed of the ->jump and ->call
   bits.  This field indicates whether the label is an alternate
   entry point, and if so, what kind.  */
enum label_kind
{
  LABEL_NORMAL = 0, /* ordinary label */
  LABEL_STATIC_ENTRY, /* alternate entry point, not exported */
  LABEL_GLOBAL_ENTRY, /* alternate entry point, exported */
  LABEL_WEAK_ENTRY  /* alternate entry point, exported as weak symbol */
};

#if defined ENABLE_RTL_FLAG_CHECKING && (GCC_VERSION > 2007)

/* Retrieve the kind of LABEL.  */
#define LABEL_KIND(LABEL) __extension__         \
({ rtx const _label = (LABEL);            \
   if (GET_CODE (_label) != CODE_LABEL)         \
     rtl_check_failed_flag ("LABEL_KIND", _label, __FILE__, __LINE__, \
          __FUNCTION__);        \
   (enum label_kind) ((_label->jump << 1) | _label->call); })

/* Set the kind of LABEL.  */
#define SET_LABEL_KIND(LABEL, KIND) do {        \
   rtx _label = (LABEL);            \
   unsigned int _kind = (KIND);           \
   if (GET_CODE (_label) != CODE_LABEL)         \
     rtl_check_failed_flag ("SET_LABEL_KIND", _label, __FILE__, __LINE__, \
          __FUNCTION__);        \
   _label->jump = ((_kind >> 1) & 1);         \
   _label->call = (_kind & 1);            \
} while (0)

#else

/* Retrieve the kind of LABEL.  */
#define LABEL_KIND(LABEL) \
   ((enum label_kind) (((LABEL)->jump << 1) | (LABEL)->call))

/* Set the kind of LABEL.  */
#define SET_LABEL_KIND(LABEL, KIND) do {        \
   rtx _label = (LABEL);            \
   unsigned int _kind = (KIND);           \
   _label->jump = ((_kind >> 1) & 1);         \
   _label->call = (_kind & 1);            \
} while (0)

#endif /* rtl flag checking */

#define LABEL_ALT_ENTRY_P(LABEL) (LABEL_KIND (LABEL) != LABEL_NORMAL)

/* The original regno this ADDRESSOF was built for.  */
#define ADDRESSOF_REGNO(RTX) XCUINT (RTX, 1, ADDRESSOF)

/* The variable in the register we took the address of.  */
#define ADDRESSOF_DECL(RTX) XCTREE (RTX, 2, ADDRESSOF)

/* In jump.c, each JUMP_INSN can point to a label that it can jump to,
   so that if the JUMP_INSN is deleted, the label's LABEL_NUSES can
   be decremented and possibly the label can be deleted.  */
#define JUMP_LABEL(INSN)   XCEXP (INSN, 9, JUMP_INSN)

/* Once basic blocks are found in flow.c,
   each CODE_LABEL starts a chain that goes through
   all the LABEL_REFs that jump to that label.
   The chain eventually winds up at the CODE_LABEL: it is circular.  */
#define LABEL_REFS(LABEL) XCEXP (LABEL, 5, CODE_LABEL)

/* This is the field in the LABEL_REF through which the circular chain
   of references to a particular label is linked.
   This chain is set up in flow.c.  */

#define LABEL_NEXTREF(REF) XCEXP (REF, 1, LABEL_REF)

/* Once basic blocks are found in flow.c,
   Each LABEL_REF points to its containing instruction with this field.  */

#define CONTAINING_INSN(RTX) XCEXP (RTX, 2, LABEL_REF)

/* For a REG rtx, REGNO extracts the register number.  ORIGINAL_REGNO holds
   the number the register originally had; for a pseudo register turned into
   a hard reg this will hold the old pseudo register number.  */

#define REGNO(RTX) XCUINT (RTX, 0, REG)
#define ORIGINAL_REGNO(RTX) X0UINT (RTX, 1)

/* 1 if RTX is a reg or parallel that is the current function's return
   value.  */
#define REG_FUNCTION_VALUE_P(RTX)         \
  (RTL_FLAG_CHECK2("REG_FUNCTION_VALUE_P", (RTX), REG, PARALLEL)->integrated)

/* 1 if RTX is a reg that corresponds to a variable declared by the user.  */
#define REG_USERVAR_P(RTX)            \
  (RTL_FLAG_CHECK1("REG_USERVAR_P", (RTX), REG)->volatil)

/* 1 if RTX is a reg that holds a pointer value.  */
#define REG_POINTER(RTX)            \
  (RTL_FLAG_CHECK1("REG_POINTER", (RTX), REG)->frame_related)

/* 1 if the given register REG corresponds to a hard register.  */
#define HARD_REGISTER_P(REG) (HARD_REGISTER_NUM_P (REGNO (REG)))

/* 1 if the given register number REG_NO corresponds to a hard register.  */
#define HARD_REGISTER_NUM_P(REG_NO) ((REG_NO) < FIRST_PSEUDO_REGISTER)

/* For a CONST_INT rtx, INTVAL extracts the integer.  */

#define INTVAL(RTX) XCWINT(RTX, 0, CONST_INT)

/* For a CONST_DOUBLE:
   For a DImode, there are two integers CONST_DOUBLE_LOW is the
     low-order word and ..._HIGH the high-order.
   For a float, there is a REAL_VALUE_TYPE structure, and 
     CONST_DOUBLE_REAL_VALUE(r) is a pointer to it.  */
#define CONST_DOUBLE_LOW(r) XCWINT (r, 0, CONST_DOUBLE)
#define CONST_DOUBLE_HIGH(r) XCWINT (r, 1, CONST_DOUBLE)
#define CONST_DOUBLE_REAL_VALUE(r) ((struct real_value *)&CONST_DOUBLE_LOW(r))

/* For a CONST_VECTOR, return element #n.  */
#define CONST_VECTOR_ELT(RTX, N) XCVECEXP (RTX, 0, N, CONST_VECTOR)

/* For a CONST_VECTOR, return the number of elements in a vector.  */
#define CONST_VECTOR_NUNITS(RTX) XCVECLEN (RTX, 0, CONST_VECTOR)

/* For a SUBREG rtx, SUBREG_REG extracts the value we want a subreg of.
   SUBREG_BYTE extracts the byte-number.  */

#define SUBREG_REG(RTX) XCEXP (RTX, 0, SUBREG)
#define SUBREG_BYTE(RTX) XCUINT (RTX, 1, SUBREG)

/* in rtlanal.c */
extern unsigned int subreg_lsb    PARAMS ((rtx));
extern unsigned int subreg_regno_offset   PARAMS ((unsigned int, 
               enum machine_mode, 
               unsigned int, 
               enum machine_mode));
extern bool subreg_offset_representable_p   PARAMS ((unsigned int, 
               enum machine_mode, 
               unsigned int, 
               enum machine_mode));
extern unsigned int subreg_regno  PARAMS ((rtx));

/* 1 if RTX is a subreg containing a reg that is already known to be
   sign- or zero-extended from the mode of the subreg to the mode of
   the reg.  SUBREG_PROMOTED_UNSIGNED_P gives the signedness of the
   extension.

   When used as a LHS, is means that this extension must be done
   when assigning to SUBREG_REG.  */

#define SUBREG_PROMOTED_VAR_P(RTX)          \
  (RTL_FLAG_CHECK1("SUBREG_PROMOTED", (RTX), SUBREG)->in_struct)

#define SUBREG_PROMOTED_UNSIGNED_SET(RTX, VAL)        \
do {                  \
  rtx const _rtx = RTL_FLAG_CHECK1("SUBREG_PROMOTED_UNSIGNED_SET", (RTX), SUBREG); \
  if ((VAL) < 0)              \
    _rtx->volatil = 1;              \
  else {                \
    _rtx->volatil = 0;              \
    _rtx->unchanging = (VAL);           \
  }                 \
} while (0)
#define SUBREG_PROMOTED_UNSIGNED_P(RTX) \
  ((RTL_FLAG_CHECK1("SUBREG_PROMOTED_UNSIGNED_P", (RTX), SUBREG)->volatil) \
     ? -1 : (RTX)->unchanging)

/* Access various components of an ASM_OPERANDS rtx.  */

#define ASM_OPERANDS_TEMPLATE(RTX) XCSTR (RTX, 0, ASM_OPERANDS)
#define ASM_OPERANDS_OUTPUT_CONSTRAINT(RTX) XCSTR (RTX, 1, ASM_OPERANDS)
#define ASM_OPERANDS_OUTPUT_IDX(RTX) XCINT (RTX, 2, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT_VEC(RTX) XCVEC (RTX, 3, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT_CONSTRAINT_VEC(RTX) XCVEC (RTX, 4, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT(RTX, N) XCVECEXP (RTX, 3, N, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT_LENGTH(RTX) XCVECLEN (RTX, 3, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT_CONSTRAINT_EXP(RTX, N) \
  XCVECEXP (RTX, 4, N, ASM_OPERANDS)
#define ASM_OPERANDS_INPUT_CONSTRAINT(RTX, N) \
  XSTR (XCVECEXP (RTX, 4, N, ASM_OPERANDS), 0)
#define ASM_OPERANDS_INPUT_MODE(RTX, N)  \
  GET_MODE (XCVECEXP (RTX, 4, N, ASM_OPERANDS))
#define ASM_OPERANDS_SOURCE_FILE(RTX) XCSTR (RTX, 5, ASM_OPERANDS)
#define ASM_OPERANDS_SOURCE_LINE(RTX) XCINT (RTX, 6, ASM_OPERANDS)

/* 1 if RTX is a mem and we should keep the alias set for this mem
   unchanged when we access a component.  Set to 1, or example, when we
   are already in a non-addressable component of an aggregate.  */
#define MEM_KEEP_ALIAS_SET_P(RTX)         \
  (RTL_FLAG_CHECK1("MEM_KEEP_ALIAS_SET_P", (RTX), MEM)->jump)

/* 1 if RTX is a mem or asm_operand for a volatile reference.  */
#define MEM_VOLATILE_P(RTX)           \
  (RTL_FLAG_CHECK3("MEM_VOLATILE_P", (RTX), MEM, ASM_OPERANDS,    \
       ASM_INPUT)->volatil)

/* 1 if RTX is a mem that refers to an aggregate, either to the
   aggregate itself of to a field of the aggregate.  If zero, RTX may
   or may not be such a reference.  */
#define MEM_IN_STRUCT_P(RTX)            \
  (RTL_FLAG_CHECK1("MEM_IN_STRUCT_P", (RTX), MEM)->in_struct)

/* 1 if RTX is a mem that refers to a scalar.  If zero, RTX may or may
   not refer to a scalar.  */
#define MEM_SCALAR_P(RTX)           \
  (RTL_FLAG_CHECK1("MEM_SCALAR_P", (RTX), MEM)->frame_related)

/* 1 if RTX is a mem that cannot trap.  */
#define MEM_NOTRAP_P(RTX) \
  (RTL_FLAG_CHECK1("MEM_NOTRAP_P", (RTX), MEM)->call)

/* If VAL is nonzero, set MEM_IN_STRUCT_P and clear MEM_SCALAR_P in
   RTX.  Otherwise, vice versa.  Use this macro only when you are
   *sure* that you know that the MEM is in a structure, or is a
   scalar.  VAL is evaluated only once.  */
#define MEM_SET_IN_STRUCT_P(RTX, VAL)   \
do {            \
  if (VAL)          \
    {           \
      MEM_IN_STRUCT_P (RTX) = 1;    \
      MEM_SCALAR_P (RTX) = 0;     \
    }           \
  else            \
    {           \
      MEM_IN_STRUCT_P (RTX) = 0;    \
      MEM_SCALAR_P (RTX) = 1;     \
    }           \
} while (0)

/* The memory attribute block.  We provide access macros for each value
   in the block and provide defaults if none specified.  */
#define MEM_ATTRS(RTX) X0MEMATTR (RTX, 1)

/* For a MEM rtx, the alias set.  If 0, this MEM is not in any alias
   set, and may alias anything.  Otherwise, the MEM can only alias
   MEMs in the same alias set.  This value is set in a
   language-dependent manner in the front-end, and should not be
   altered in the back-end.  These set numbers are tested for zero,
   and compared for equality; they have no other significance.  In
   some front-ends, these numbers may correspond in some way to types,
   or other language-level entities, but they need not, and the
   back-end makes no such assumptions.  */
#define MEM_ALIAS_SET(RTX) (MEM_ATTRS (RTX) == 0 ? 0 : MEM_ATTRS (RTX)->alias)

/* For a MEM rtx, the decl it is known to refer to, if it is known to
   refer to part of a DECL.  It may also be a COMPONENT_REF.  */
#define MEM_EXPR(RTX) (MEM_ATTRS (RTX) == 0 ? 0 : MEM_ATTRS (RTX)->expr)

/* For a MEM rtx, the offset from the start of MEM_EXPR, if known, as a
   RTX that is always a CONST_INT.  */
#define MEM_OFFSET(RTX) (MEM_ATTRS (RTX) == 0 ? 0 : MEM_ATTRS (RTX)->offset)

/* For a MEM rtx, the size in bytes of the MEM, if known, as an RTX that
   is always a CONST_INT.  */
#define MEM_SIZE(RTX)             \
(MEM_ATTRS (RTX) != 0 ? MEM_ATTRS (RTX)->size       \
 : GET_MODE (RTX) != BLKmode ? GEN_INT (GET_MODE_SIZE (GET_MODE (RTX))) \
 : 0)

/* For a MEM rtx, the alignment in bits.  We can use the alignment of the
   mode as a default when STRICT_ALIGNMENT, but not if not.  */
#define MEM_ALIGN(RTX)              \
(MEM_ATTRS (RTX) != 0 ? MEM_ATTRS (RTX)->align        \
 : (STRICT_ALIGNMENT && GET_MODE (RTX) != BLKmode     \
    ? GET_MODE_ALIGNMENT (GET_MODE (RTX)) : BITS_PER_UNIT))

/* Copy the attributes that apply to memory locations from RHS to LHS.  */
#define MEM_COPY_ATTRIBUTES(LHS, RHS)       \
  (MEM_VOLATILE_P (LHS) = MEM_VOLATILE_P (RHS),     \
   MEM_IN_STRUCT_P (LHS) = MEM_IN_STRUCT_P (RHS),   \
   MEM_SCALAR_P (LHS) = MEM_SCALAR_P (RHS),     \
   MEM_NOTRAP_P (LHS) = MEM_NOTRAP_P (RHS),     \
   RTX_UNCHANGING_P (LHS) = RTX_UNCHANGING_P (RHS),   \
   MEM_KEEP_ALIAS_SET_P (LHS) = MEM_KEEP_ALIAS_SET_P (RHS), \
   MEM_ATTRS (LHS) = MEM_ATTRS (RHS))

/* 1 if RTX is a label_ref to a label outside the loop containing the
   reference.  */
#define LABEL_OUTSIDE_LOOP_P(RTX)         \
  (RTL_FLAG_CHECK1("LABEL_OUTSIDE_LOOP_P", (RTX), LABEL_REF)->in_struct)

/* 1 if RTX is a label_ref for a nonlocal label.  */
/* Likewise in an expr_list for a reg_label note.  */
#define LABEL_REF_NONLOCAL_P(RTX)         \
  (RTL_FLAG_CHECK2("LABEL_REF_NONLOCAL_P", (RTX), LABEL_REF,    \
       REG_LABEL)->volatil)

/* 1 if RTX is a code_label that should always be considered to be needed.  */
#define LABEL_PRESERVE_P(RTX)           \
  (RTL_FLAG_CHECK2("LABEL_PRESERVE_P", (RTX), CODE_LABEL, NOTE)->in_struct)

/* 1 if RTX is a reg that is used only in an exit test of a loop.  */
#define REG_LOOP_TEST_P(RTX)            \
  (RTL_FLAG_CHECK1("REG_LOOP_TEST_P", (RTX), REG)->in_struct)

/* During sched, 1 if RTX is an insn that must be scheduled together
   with the preceding insn.  */
#define SCHED_GROUP_P(RTX)            \
  (RTL_FLAG_CHECK3("SCHED_GROUP_P", (RTX), INSN, JUMP_INSN, CALL_INSN \
              )->in_struct)

/* For a SET rtx, SET_DEST is the place that is set
   and SET_SRC is the value it is set to.  */
#define SET_DEST(RTX) XC2EXP(RTX, 0, SET, CLOBBER)
#define SET_SRC(RTX) XCEXP(RTX, 1, SET)
#define SET_IS_RETURN_P(RTX)            \
  (RTL_FLAG_CHECK1("SET_IS_RETURN_P", (RTX), SET)->jump)

/* For a TRAP_IF rtx, TRAP_CONDITION is an expression.  */
#define TRAP_CONDITION(RTX) XCEXP (RTX, 0, TRAP_IF)
#define TRAP_CODE(RTX) XCEXP (RTX, 1, TRAP_IF)

/* For a COND_EXEC rtx, COND_EXEC_TEST is the condition to base
   conditionally executing the code on, COND_EXEC_CODE is the code
   to execute if the condition is true.  */
#define COND_EXEC_TEST(RTX) XCEXP (RTX, 0, COND_EXEC)
#define COND_EXEC_CODE(RTX) XCEXP (RTX, 1, COND_EXEC)

/* 1 if RTX is a symbol_ref that addresses this function's constants pool.  */
#define CONSTANT_POOL_ADDRESS_P(RTX)          \
  (RTL_FLAG_CHECK1("CONSTANT_POOL_ADDRESS_P", (RTX), SYMBOL_REF)->unchanging)

/* 1 if RTX is a symbol_ref that addresses this function's string constant
   pool  */
#define STRING_POOL_ADDRESS_P(RTX)          \
  (RTL_FLAG_CHECK1("STRING_POOL_ADDRESS_P", (RTX), SYMBOL_REF)->frame_related)

/* Used if RTX is a symbol_ref, for machine-specific purposes.  */
#define SYMBOL_REF_FLAG(RTX)            \
  (RTL_FLAG_CHECK1("SYMBOL_REF_FLAG", (RTX), SYMBOL_REF)->volatil)

/* 1 if RTX is a symbol_ref that has been the library function in
   emit_library_call.  */
#define SYMBOL_REF_USED(RTX)            \
  (RTL_FLAG_CHECK1("SYMBOL_REF_USED", (RTX), SYMBOL_REF)->used)

/* 1 if RTX is a symbol_ref for a weak symbol.  */
#define SYMBOL_REF_WEAK(RTX)            \
  (RTL_FLAG_CHECK1("SYMBOL_REF_WEAK", (RTX), SYMBOL_REF)->integrated)

/* Define a macro to look for REG_INC notes,
   but save time on machines where they never exist.  */

#if (defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT) || defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT))
#define FIND_REG_INC_NOTE(INSN, REG)      \
  ((REG) != NULL_RTX && REG_P ((REG))     \
   ? find_regno_note ((INSN), REG_INC, REGNO (REG)) \
   : find_reg_note ((INSN), REG_INC, (REG)))
#else
#define FIND_REG_INC_NOTE(INSN, REG) 0
#endif

/* Indicate whether the machine has any sort of auto increment addressing.
   If not, we can avoid checking for REG_INC notes.  */

#if (defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT) || defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT))
#define AUTO_INC_DEC
#endif

#ifndef HAVE_PRE_INCREMENT
#define HAVE_PRE_INCREMENT 0
#endif

#ifndef HAVE_PRE_DECREMENT
#define HAVE_PRE_DECREMENT 0
#endif

#ifndef HAVE_POST_INCREMENT
#define HAVE_POST_INCREMENT 0
#endif

#ifndef HAVE_POST_DECREMENT
#define HAVE_POST_DECREMENT 0
#endif

#ifndef HAVE_POST_MODIFY_DISP
#define HAVE_POST_MODIFY_DISP 0
#endif

#ifndef HAVE_POST_MODIFY_REG
#define HAVE_POST_MODIFY_REG 0
#endif

#ifndef HAVE_PRE_MODIFY_DISP
#define HAVE_PRE_MODIFY_DISP 0
#endif

#ifndef HAVE_PRE_MODIFY_REG
#define HAVE_PRE_MODIFY_REG 0
#endif


/* Some architectures do not have complete pre/post increment/decrement
   instruction sets, or only move some modes efficiently.  These macros
   allow us to tune autoincrement generation.  */

#ifndef USE_LOAD_POST_INCREMENT
#define USE_LOAD_POST_INCREMENT(MODE)   HAVE_POST_INCREMENT
#endif

#ifndef USE_LOAD_POST_DECREMENT
#define USE_LOAD_POST_DECREMENT(MODE)   HAVE_POST_DECREMENT
#endif

#ifndef USE_LOAD_PRE_INCREMENT
#define USE_LOAD_PRE_INCREMENT(MODE)    HAVE_PRE_INCREMENT
#endif

#ifndef USE_LOAD_PRE_DECREMENT
#define USE_LOAD_PRE_DECREMENT(MODE)    HAVE_PRE_DECREMENT
#endif

#ifndef USE_STORE_POST_INCREMENT
#define USE_STORE_POST_INCREMENT(MODE)  HAVE_POST_INCREMENT
#endif

#ifndef USE_STORE_POST_DECREMENT
#define USE_STORE_POST_DECREMENT(MODE)  HAVE_POST_DECREMENT
#endif

#ifndef USE_STORE_PRE_INCREMENT
#define USE_STORE_PRE_INCREMENT(MODE)   HAVE_PRE_INCREMENT
#endif

#ifndef USE_STORE_PRE_DECREMENT
#define USE_STORE_PRE_DECREMENT(MODE)   HAVE_PRE_DECREMENT
#endif

/* Determine if the insn is a PHI node.  */
#define PHI_NODE_P(X)       \
  ((X) && GET_CODE (X) == INSN      \
   && GET_CODE (PATTERN (X)) == SET   \
   && GET_CODE (SET_SRC (PATTERN (X))) == PHI)

/* Nonzero if we need to distinguish between the return value of this function
   and the return value of a function called by this function.  This helps
   integrate.c.
   This is 1 until after the rtl generation pass.  */
extern int rtx_equal_function_value_matters;

/* Nonzero when we are generating CONCATs.  */
extern int generating_concat_p;

/* Generally useful functions.  */

/* In expmed.c */
extern int ceil_log2      PARAMS ((unsigned HOST_WIDE_INT));

#define plus_constant(X, C) plus_constant_wide ((X), (HOST_WIDE_INT) (C))

/* In builtins.c */
extern rtx expand_builtin_expect_jump PARAMS ((tree, rtx, rtx));

/* In explow.c */
extern void set_stack_check_libfunc PARAMS ((rtx));
extern HOST_WIDE_INT trunc_int_for_mode PARAMS ((HOST_WIDE_INT,
                 enum machine_mode));
extern rtx plus_constant_wide    PARAMS ((rtx, HOST_WIDE_INT));
extern rtx plus_constant_for_output_wide PARAMS ((rtx, HOST_WIDE_INT));
extern void optimize_save_area_alloca PARAMS ((rtx));

/* In emit-rtl.c */
extern rtx gen_rtx      PARAMS ((enum rtx_code,
             enum machine_mode, ...));
extern rtvec gen_rtvec      PARAMS ((int, ...));
extern rtx copy_insn_1      PARAMS ((rtx));
extern rtx copy_insn      PARAMS ((rtx));
extern rtx gen_int_mode     PARAMS ((HOST_WIDE_INT,
             enum machine_mode));
extern rtx emit_copy_of_insn_after  PARAMS ((rtx, rtx));

/* In rtl.c */
extern rtx rtx_alloc      PARAMS ((RTX_CODE));
extern rtvec rtvec_alloc    PARAMS ((int));
extern rtx copy_rtx     PARAMS ((rtx));

/* In emit-rtl.c */
extern rtx copy_rtx_if_shared   PARAMS ((rtx));

/* In rtl.c */
extern rtx copy_most_rtx    PARAMS ((rtx, rtx));
extern rtx shallow_copy_rtx   PARAMS ((rtx));
extern int rtx_equal_p                  PARAMS ((rtx, rtx));

/* In emit-rtl.c */
extern rtvec gen_rtvec_v    PARAMS ((int, rtx *));
extern rtx gen_reg_rtx      PARAMS ((enum machine_mode));
extern rtx gen_label_rtx    PARAMS ((void));
extern int subreg_hard_regno    PARAMS ((rtx, int));
extern rtx gen_lowpart_common   PARAMS ((enum machine_mode, rtx));
extern rtx gen_lowpart      PARAMS ((enum machine_mode, rtx));

/* In cse.c */
extern rtx gen_lowpart_if_possible  PARAMS ((enum machine_mode, rtx));

/* In emit-rtl.c */
extern rtx gen_highpart     PARAMS ((enum machine_mode, rtx));
extern rtx gen_highpart_mode    PARAMS ((enum machine_mode,
             enum machine_mode, rtx));
extern rtx gen_realpart     PARAMS ((enum machine_mode, rtx));
extern rtx gen_imagpart     PARAMS ((enum machine_mode, rtx));
extern rtx operand_subword    PARAMS ((rtx, unsigned int, int,
             enum machine_mode));
extern rtx constant_subword   PARAMS ((rtx, int,
             enum machine_mode));

/* In emit-rtl.c */
extern rtx operand_subword_force  PARAMS ((rtx, unsigned int,
             enum machine_mode));
extern int subreg_lowpart_p   PARAMS ((rtx));
extern unsigned int subreg_lowpart_offset PARAMS ((enum machine_mode,
               enum machine_mode));
extern unsigned int subreg_highpart_offset PARAMS ((enum machine_mode,
                enum machine_mode));
extern rtx make_safe_from   PARAMS ((rtx, rtx));
extern rtx convert_memory_address PARAMS ((enum machine_mode, rtx));
extern rtx get_insns      PARAMS ((void));
extern const char *get_insn_name  PARAMS ((int));
extern rtx get_last_insn    PARAMS ((void));
extern rtx get_last_insn_anywhere PARAMS ((void));
extern rtx get_first_nonnote_insn PARAMS ((void));
extern rtx get_last_nonnote_insn  PARAMS ((void));
extern void start_sequence    PARAMS ((void));
extern void push_to_sequence    PARAMS ((rtx));
extern void end_sequence    PARAMS ((void));
extern void push_to_full_sequence PARAMS ((rtx, rtx));
extern void end_full_sequence   PARAMS ((rtx*, rtx*));

/* In varasm.c  */
extern rtx immed_double_const   PARAMS ((HOST_WIDE_INT, HOST_WIDE_INT, enum machine_mode));
extern rtx mem_for_const_double   PARAMS ((rtx));
extern rtx force_const_mem    PARAMS ((enum machine_mode, rtx));

/* In varasm.c  */
extern rtx get_pool_constant    PARAMS ((rtx));
extern rtx get_pool_constant_mark PARAMS ((rtx, bool *));
extern enum machine_mode get_pool_mode  PARAMS ((rtx));
extern rtx get_pool_constant_for_function PARAMS ((struct function *, rtx));
extern enum machine_mode get_pool_mode_for_function PARAMS ((struct function *, rtx));
extern int get_pool_offset    PARAMS ((rtx));
extern rtx simplify_subtraction   PARAMS ((rtx));

/* In function.c  */
extern rtx assign_stack_local   PARAMS ((enum machine_mode,
                 HOST_WIDE_INT, int));
extern rtx assign_stack_temp    PARAMS ((enum machine_mode,
                 HOST_WIDE_INT, int));
extern rtx assign_stack_temp_for_type PARAMS ((enum machine_mode,
             HOST_WIDE_INT, int, tree));
extern rtx assign_temp      PARAMS ((tree, int, int, int));
/* In emit-rtl.c */
extern rtx emit_insn_before   PARAMS ((rtx, rtx));
extern rtx emit_insn_before_scope PARAMS ((rtx, rtx, tree));
extern rtx emit_jump_insn_before  PARAMS ((rtx, rtx));
extern rtx emit_jump_insn_before_scope  PARAMS ((rtx, rtx, tree));
extern rtx emit_call_insn_before  PARAMS ((rtx, rtx));
extern rtx emit_call_insn_before_scope  PARAMS ((rtx, rtx, tree));
extern rtx emit_barrier_before    PARAMS ((rtx));
extern rtx emit_label_before    PARAMS ((rtx, rtx));
extern rtx emit_note_before   PARAMS ((int, rtx));
extern rtx emit_insn_after    PARAMS ((rtx, rtx));
extern rtx emit_insn_after_scope  PARAMS ((rtx, rtx, tree));
extern rtx emit_jump_insn_after   PARAMS ((rtx, rtx));
extern rtx emit_jump_insn_after_scope PARAMS ((rtx, rtx, tree));
extern rtx emit_call_insn_after   PARAMS ((rtx, rtx));
extern rtx emit_call_insn_after_scope PARAMS ((rtx, rtx, tree));
extern rtx emit_barrier_after   PARAMS ((rtx));
extern rtx emit_label_after   PARAMS ((rtx, rtx));
extern rtx emit_note_after    PARAMS ((int, rtx));
extern rtx emit_line_note_after   PARAMS ((const char *, int, rtx));
extern rtx emit_insn      PARAMS ((rtx));
extern rtx emit_jump_insn   PARAMS ((rtx));
extern rtx emit_call_insn   PARAMS ((rtx));
extern rtx emit_label     PARAMS ((rtx));
extern rtx emit_barrier     PARAMS ((void));
extern rtx emit_line_note   PARAMS ((const char *, int));
extern rtx emit_note      PARAMS ((const char *, int));
extern rtx emit_line_note_force   PARAMS ((const char *, int));
extern rtx make_insn_raw    PARAMS ((rtx));
extern rtx previous_insn    PARAMS ((rtx));
extern rtx next_insn      PARAMS ((rtx));
extern rtx prev_nonnote_insn    PARAMS ((rtx));
extern rtx next_nonnote_insn    PARAMS ((rtx));
extern rtx prev_real_insn   PARAMS ((rtx));
extern rtx next_real_insn   PARAMS ((rtx));
extern rtx prev_active_insn   PARAMS ((rtx));
extern rtx next_active_insn   PARAMS ((rtx));
extern int active_insn_p    PARAMS ((rtx));
extern rtx prev_label     PARAMS ((rtx));
extern rtx next_label     PARAMS ((rtx));
extern rtx next_cc0_user    PARAMS ((rtx));
extern rtx prev_cc0_setter    PARAMS ((rtx));

/* In cfglayout.c  */
extern tree choose_inner_scope    PARAMS ((tree, tree));

/* In jump.c */
extern rtx next_nondeleted_insn   PARAMS ((rtx));
extern enum rtx_code reverse_condition  PARAMS ((enum rtx_code));
extern enum rtx_code reverse_condition_maybe_unordered PARAMS ((enum rtx_code));
extern enum rtx_code swap_condition PARAMS ((enum rtx_code));
extern enum rtx_code unsigned_condition PARAMS ((enum rtx_code));
extern enum rtx_code signed_condition PARAMS ((enum rtx_code));
extern void mark_jump_label   PARAMS ((rtx, rtx, int));
extern void cleanup_barriers    PARAMS ((void));

/* In jump.c */
extern bool squeeze_notes   PARAMS ((rtx *, rtx *));
extern rtx delete_related_insns     PARAMS ((rtx));
extern void delete_jump     PARAMS ((rtx));
extern void delete_barrier    PARAMS ((rtx));
extern rtx get_label_before   PARAMS ((rtx));
extern rtx get_label_after    PARAMS ((rtx));
extern rtx follow_jumps     PARAMS ((rtx));

/* In recog.c  */
extern rtx *find_constant_term_loc  PARAMS ((rtx *));

/* In emit-rtl.c  */
extern rtx try_split      PARAMS ((rtx, rtx, int));
extern int split_branch_probability;

/* In unknown file  */
extern rtx split_insns      PARAMS ((rtx, rtx));

/* In simplify-rtx.c  */
extern rtx simplify_unary_operation PARAMS ((enum rtx_code,
             enum machine_mode, rtx,
             enum machine_mode));
extern rtx simplify_binary_operation  PARAMS ((enum rtx_code,
             enum machine_mode, rtx,
             rtx));
extern rtx simplify_ternary_operation PARAMS ((enum rtx_code,
             enum machine_mode,
             enum machine_mode, rtx, rtx,
             rtx));
extern rtx simplify_relational_operation PARAMS ((enum rtx_code,
              enum machine_mode, rtx,
              rtx));
extern rtx simplify_gen_binary    PARAMS ((enum rtx_code,
             enum machine_mode,
             rtx, rtx));
extern rtx simplify_gen_unary   PARAMS ((enum rtx_code,
             enum machine_mode, rtx,
             enum machine_mode));
extern rtx simplify_gen_ternary   PARAMS ((enum rtx_code,
             enum machine_mode,
             enum machine_mode,
             rtx, rtx, rtx));
extern rtx simplify_gen_relational  PARAMS ((enum rtx_code,
             enum machine_mode,
             enum machine_mode,
             rtx, rtx));
extern rtx simplify_subreg    PARAMS ((enum machine_mode,
             rtx,
             enum machine_mode,
             unsigned int));
extern rtx simplify_gen_subreg    PARAMS ((enum machine_mode,
             rtx,
             enum machine_mode,
             unsigned int));
extern rtx simplify_replace_rtx   PARAMS ((rtx, rtx, rtx));
extern rtx simplify_rtx     PARAMS ((rtx));
extern rtx avoid_constant_pool_reference PARAMS ((rtx));

/* In function.c  */
extern rtx gen_mem_addressof    PARAMS ((rtx, tree, int));

/* In regclass.c  */
extern enum machine_mode choose_hard_reg_mode PARAMS ((unsigned int,
                   unsigned int));

/* In emit-rtl.c  */
extern rtx set_unique_reg_note    PARAMS ((rtx, enum reg_note, rtx));

/* Functions in rtlanal.c */

/* Single set is implemented as macro for performance reasons.  */
#define single_set(I) (INSN_P (I) \
           ? (GET_CODE (PATTERN (I)) == SET \
        ? PATTERN (I) : single_set_1 (I)) \
           : NULL_RTX)
#define single_set_1(I) single_set_2 (I, PATTERN (I))

extern int rtx_addr_can_trap_p    PARAMS ((rtx));
extern int rtx_unstable_p   PARAMS ((rtx));
extern int rtx_varies_p     PARAMS ((rtx, int));
extern int rtx_addr_varies_p    PARAMS ((rtx, int));
extern HOST_WIDE_INT get_integer_term PARAMS ((rtx));
extern rtx get_related_value    PARAMS ((rtx));
extern rtx get_jump_table_offset  PARAMS ((rtx, rtx *));
extern int global_reg_mentioned_p PARAMS ((rtx));
extern int reg_mentioned_p    PARAMS ((rtx, rtx));
extern int count_occurrences    PARAMS ((rtx, rtx, int));
extern int reg_referenced_p   PARAMS ((rtx, rtx));
extern int reg_used_between_p   PARAMS ((rtx, rtx, rtx));
extern int reg_referenced_between_p PARAMS ((rtx, rtx, rtx));
extern int reg_set_between_p    PARAMS ((rtx, rtx, rtx));
extern int regs_set_between_p   PARAMS ((rtx, rtx, rtx));
extern int commutative_operand_precedence PARAMS ((rtx));
extern int swap_commutative_operands_p  PARAMS ((rtx, rtx));
extern int modified_between_p   PARAMS ((rtx, rtx, rtx));
extern int no_labels_between_p    PARAMS ((rtx, rtx));
extern int no_jumps_between_p   PARAMS ((rtx, rtx));
extern int modified_in_p    PARAMS ((rtx, rtx));
extern int insn_dependent_p   PARAMS ((rtx, rtx));
extern int reg_set_p      PARAMS ((rtx, rtx));
extern rtx single_set_2     PARAMS ((rtx, rtx));
extern int multiple_sets    PARAMS ((rtx));
extern int set_noop_p     PARAMS ((rtx));
extern int noop_move_p      PARAMS ((rtx));
extern rtx find_last_value    PARAMS ((rtx, rtx *, rtx, int));
extern int refers_to_regno_p    PARAMS ((unsigned int, unsigned int,
             rtx, rtx *));
extern int reg_overlap_mentioned_p  PARAMS ((rtx, rtx));
extern rtx set_of     PARAMS ((rtx, rtx));
extern void note_stores     PARAMS ((rtx,
             void (*) (rtx, rtx, void *),
             void *));
extern void note_uses     PARAMS ((rtx *,
             void (*) (rtx *, void *),
             void *));
extern rtx reg_set_last     PARAMS ((rtx, rtx));
extern int dead_or_set_p    PARAMS ((rtx, rtx));
extern int dead_or_set_regno_p    PARAMS ((rtx, unsigned int));
extern rtx find_reg_note    PARAMS ((rtx, enum reg_note, rtx));
extern rtx find_regno_note    PARAMS ((rtx, enum reg_note,
             unsigned int));
extern rtx find_reg_equal_equiv_note  PARAMS ((rtx));
extern int find_reg_fusage    PARAMS ((rtx, enum rtx_code, rtx));
extern int find_regno_fusage    PARAMS ((rtx, enum rtx_code,
             unsigned int));
extern int pure_call_p      PARAMS ((rtx));
extern void remove_note     PARAMS ((rtx, rtx));
extern int side_effects_p   PARAMS ((rtx));
extern int volatile_refs_p    PARAMS ((rtx));
extern int volatile_insn_p    PARAMS ((rtx));
extern int may_trap_p     PARAMS ((rtx));
extern int inequality_comparisons_p PARAMS ((rtx));
extern rtx replace_rtx      PARAMS ((rtx, rtx, rtx));
extern rtx replace_regs     PARAMS ((rtx, rtx *, unsigned int,
             int));
extern int computed_jump_p    PARAMS ((rtx));
typedef int (*rtx_function)             PARAMS ((rtx *, void *));
extern int for_each_rtx                 PARAMS ((rtx *, rtx_function, void *));
extern rtx regno_use_in     PARAMS ((unsigned int, rtx));
extern int auto_inc_p     PARAMS ((rtx));
extern int in_expr_list_p   PARAMS ((rtx, rtx));
extern void remove_node_from_expr_list  PARAMS ((rtx, rtx *));
extern int insns_safe_to_move_p         PARAMS ((rtx, rtx, rtx *));
extern int loc_mentioned_in_p   PARAMS ((rtx *, rtx));
extern rtx find_first_parameter_load  PARAMS ((rtx, rtx));
extern bool keep_with_call_p    PARAMS ((rtx));

/* flow.c */

extern rtx find_use_as_address    PARAMS ((rtx, rtx, HOST_WIDE_INT));

/* lists.c */

void free_EXPR_LIST_list    PARAMS ((rtx *));
void free_INSN_LIST_list    PARAMS ((rtx *));
void free_EXPR_LIST_node    PARAMS ((rtx));
void free_INSN_LIST_node    PARAMS ((rtx));
rtx alloc_INSN_LIST     PARAMS ((rtx, rtx));
rtx alloc_EXPR_LIST     PARAMS ((int, rtx, rtx));

/* regclass.c */

/* Maximum number of parallel sets and clobbers in any insn in this fn.
   Always at least 3, since the combiner could put that many togetherm
   and we want this to remain correct for all the remaining passes.  */

extern int max_parallel;

/* Free up register info memory.  */
extern void free_reg_info   PARAMS ((void));

/* recog.c */
extern int asm_noperands    PARAMS ((rtx));
extern const char *decode_asm_operands  PARAMS ((rtx, rtx *, rtx **,
                 const char **,
                 enum machine_mode *));

extern enum reg_class reg_preferred_class PARAMS ((int));
extern enum reg_class reg_alternate_class PARAMS ((int));

extern rtx get_first_nonparm_insn PARAMS ((void));

extern void split_all_insns   PARAMS ((int));
extern void split_all_insns_noflow  PARAMS ((void));

#define MAX_SAVED_CONST_INT 64
extern GTY(()) rtx const_int_rtx[MAX_SAVED_CONST_INT * 2 + 1];

#define const0_rtx  (const_int_rtx[MAX_SAVED_CONST_INT])
#define const1_rtx  (const_int_rtx[MAX_SAVED_CONST_INT+1])
#define const2_rtx  (const_int_rtx[MAX_SAVED_CONST_INT+2])
#define constm1_rtx (const_int_rtx[MAX_SAVED_CONST_INT-1])
extern GTY(()) rtx const_true_rtx;

extern GTY(()) rtx const_tiny_rtx[3][(int) MAX_MACHINE_MODE];

/* Returns a constant 0 rtx in mode MODE.  Integer modes are treated the
   same as VOIDmode.  */

#define CONST0_RTX(MODE) (const_tiny_rtx[0][(int) (MODE)])

/* Likewise, for the constants 1 and 2.  */

#define CONST1_RTX(MODE) (const_tiny_rtx[1][(int) (MODE)])
#define CONST2_RTX(MODE) (const_tiny_rtx[2][(int) (MODE)])

/* If HARD_FRAME_POINTER_REGNUM is defined, then a special dummy reg
   is used to represent the frame pointer.  This is because the
   hard frame pointer and the automatic variables are separated by an amount
   that cannot be determined until after register allocation.  We can assume
   that in this case ELIMINABLE_REGS will be defined, one action of which
   will be to eliminate FRAME_POINTER_REGNUM into HARD_FRAME_POINTER_REGNUM.  */
#ifndef HARD_FRAME_POINTER_REGNUM
#define HARD_FRAME_POINTER_REGNUM FRAME_POINTER_REGNUM
#endif

/* Index labels for global_rtl.  */
enum global_rtl_index
{
  GR_PC,
  GR_CC0,
  GR_STACK_POINTER,
  GR_FRAME_POINTER,
/* For register elimination to work properly these hard_frame_pointer_rtx,
   frame_pointer_rtx, and arg_pointer_rtx must be the same if they refer to
   the same register.  */
#if FRAME_POINTER_REGNUM == ARG_POINTER_REGNUM
  GR_ARG_POINTER = GR_FRAME_POINTER,
#endif
#if HARD_FRAME_POINTER_REGNUM == FRAME_POINTER_REGNUM
  GR_HARD_FRAME_POINTER = GR_FRAME_POINTER,
#else
  GR_HARD_FRAME_POINTER,
#endif
#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
#if HARD_FRAME_POINTER_REGNUM == ARG_POINTER_REGNUM
  GR_ARG_POINTER = GR_HARD_FRAME_POINTER,
#else
  GR_ARG_POINTER,
#endif
#endif
  GR_VIRTUAL_INCOMING_ARGS,
  GR_VIRTUAL_STACK_ARGS,
  GR_VIRTUAL_STACK_DYNAMIC,
  GR_VIRTUAL_OUTGOING_ARGS,
  GR_VIRTUAL_CFA,

  GR_MAX
};

/* Pointers to standard pieces of rtx are stored here.  */
extern GTY(()) rtx global_rtl[GR_MAX];

/* Standard pieces of rtx, to be substituted directly into things.  */
#define pc_rtx                  (global_rtl[GR_PC])
#define cc0_rtx                 (global_rtl[GR_CC0])

/* All references to certain hard regs, except those created
   by allocating pseudo regs into them (when that's possible),
   go through these unique rtx objects.  */
#define stack_pointer_rtx       (global_rtl[GR_STACK_POINTER])
#define frame_pointer_rtx       (global_rtl[GR_FRAME_POINTER])
#define hard_frame_pointer_rtx  (global_rtl[GR_HARD_FRAME_POINTER])
#define arg_pointer_rtx   (global_rtl[GR_ARG_POINTER])

extern GTY(()) rtx pic_offset_table_rtx;
extern GTY(()) rtx struct_value_rtx;
extern GTY(()) rtx struct_value_incoming_rtx;
extern GTY(()) rtx static_chain_rtx;
extern GTY(()) rtx static_chain_incoming_rtx;
extern GTY(()) rtx return_address_pointer_rtx;

/* Include the RTL generation functions.  */

#ifndef NO_GENRTL_H
#include "genrtl.h"
#endif

/* There are some RTL codes that require special attention; the
   generation functions included above do the raw handling.  If you
   add to this list, modify special_rtx in gengenrtl.c as well.  You
   should also modify gen_rtx to use the special function.  */

extern rtx gen_rtx_CONST_INT PARAMS ((enum machine_mode, HOST_WIDE_INT));
extern rtx gen_rtx_CONST_VECTOR PARAMS ((enum machine_mode, rtvec));
extern rtx gen_raw_REG PARAMS ((enum machine_mode, int));
extern rtx gen_rtx_REG PARAMS ((enum machine_mode, unsigned));
extern rtx gen_rtx_SUBREG PARAMS ((enum machine_mode, rtx, int));
extern rtx gen_rtx_MEM PARAMS ((enum machine_mode, rtx));

extern rtx gen_lowpart_SUBREG PARAMS ((enum machine_mode, rtx));

/* We need the cast here to ensure that we get the same result both with
   and without prototypes.  */
#define GEN_INT(N)  gen_rtx_CONST_INT (VOIDmode, (HOST_WIDE_INT) (N))

/* Virtual registers are used during RTL generation to refer to locations into
   the stack frame when the actual location isn't known until RTL generation
   is complete.  The routine instantiate_virtual_regs replaces these with
   the proper value, which is normally {frame,arg,stack}_pointer_rtx plus
   a constant.  */

#define FIRST_VIRTUAL_REGISTER  (FIRST_PSEUDO_REGISTER)

/* This points to the first word of the incoming arguments passed on the stack,
   either by the caller or by the callee when pretending it was passed by the
   caller.  */

#define virtual_incoming_args_rtx       (global_rtl[GR_VIRTUAL_INCOMING_ARGS])

#define VIRTUAL_INCOMING_ARGS_REGNUM  (FIRST_VIRTUAL_REGISTER)

/* If FRAME_GROWS_DOWNWARD, this points to immediately above the first
   variable on the stack.  Otherwise, it points to the first variable on
   the stack.  */

#define virtual_stack_vars_rtx          (global_rtl[GR_VIRTUAL_STACK_ARGS])

#define VIRTUAL_STACK_VARS_REGNUM ((FIRST_VIRTUAL_REGISTER) + 1)

/* This points to the location of dynamically-allocated memory on the stack
   immediately after the stack pointer has been adjusted by the amount
   desired.  */

#define virtual_stack_dynamic_rtx (global_rtl[GR_VIRTUAL_STACK_DYNAMIC])

#define VIRTUAL_STACK_DYNAMIC_REGNUM  ((FIRST_VIRTUAL_REGISTER) + 2)

/* This points to the location in the stack at which outgoing arguments should
   be written when the stack is pre-pushed (arguments pushed using push
   insns always use sp).  */

#define virtual_outgoing_args_rtx (global_rtl[GR_VIRTUAL_OUTGOING_ARGS])

#define VIRTUAL_OUTGOING_ARGS_REGNUM  ((FIRST_VIRTUAL_REGISTER) + 3)

/* This points to the Canonical Frame Address of the function.  This
   should corrospond to the CFA produced by INCOMING_FRAME_SP_OFFSET,
   but is calculated relative to the arg pointer for simplicity; the
   frame pointer nor stack pointer are necessarily fixed relative to
   the CFA until after reload.  */

#define virtual_cfa_rtx     (global_rtl[GR_VIRTUAL_CFA])

#define VIRTUAL_CFA_REGNUM    ((FIRST_VIRTUAL_REGISTER) + 4)

#define LAST_VIRTUAL_REGISTER   ((FIRST_VIRTUAL_REGISTER) + 4)

/* Nonzero if REGNUM is a pointer into the stack frame.  */
#define REGNO_PTR_FRAME_P(REGNUM)     \
  ((REGNUM) == STACK_POINTER_REGNUM   \
   || (REGNUM) == FRAME_POINTER_REGNUM    \
   || (REGNUM) == HARD_FRAME_POINTER_REGNUM \
   || (REGNUM) == ARG_POINTER_REGNUM    \
   || ((REGNUM) >= FIRST_VIRTUAL_REGISTER \
       && (REGNUM) <= LAST_VIRTUAL_REGISTER))

/* REGNUM never really appearing in the INSN stream.  */
#define INVALID_REGNUM      (~(unsigned int) 0)

extern rtx find_next_ref    PARAMS ((rtx, rtx));

extern rtx output_constant_def    PARAMS ((tree, int));

/* Define a default value for STORE_FLAG_VALUE.  */

#ifndef STORE_FLAG_VALUE
#define STORE_FLAG_VALUE 1
#endif

/* Nonzero after the second flow pass has completed.
   Set to 1 or 0 by toplev.c  */
extern int flow2_completed;

/* Nonzero after end of reload pass.
   Set to 1 or 0 by reload1.c.  */

extern int reload_completed;

/* Set to 1 while reload_as_needed is operating.
   Required by some machines to handle any generated moves differently.  */

extern int reload_in_progress;

/* If this is nonzero, we do not bother generating VOLATILE
   around volatile memory references, and we are willing to
   output indirect addresses.  If cse is to follow, we reject
   indirect addresses so a useful potential cse is generated;
   if it is used only once, instruction combination will produce
   the same indirect address eventually.  */
extern int cse_not_expected;

/* Set to nonzero before life analysis to indicate that it is unsafe to
   generate any new pseudo registers.  */
extern int no_new_pseudos;

/* Translates rtx code to tree code, for those codes needed by
   REAL_ARITHMETIC.  The function returns an int because the caller may not
   know what `enum tree_code' means.  */

extern int rtx_to_tree_code PARAMS ((enum rtx_code));

/* In tree.c */
struct obstack;
extern void gcc_obstack_init    PARAMS ((struct obstack *));

/* In cse.c */
struct cse_basic_block_data;

/* Return the right cost to give to an operation
   to make the cost of the corresponding register-to-register instruction
   N times that of a fast register-to-register instruction.  */
#define COSTS_N_INSNS(N) ((N) * 4)

/* Maximum cost of a rtl expression.  This value has the special meaning
   not to use an rtx with this cost under any circumstances.  */
#define MAX_COST INT_MAX

extern int rtx_cost     PARAMS ((rtx, enum rtx_code));
extern int address_cost     PARAMS ((rtx, enum machine_mode));
extern int delete_trivially_dead_insns  PARAMS ((rtx, int));
#ifdef BUFSIZ
extern int cse_main     PARAMS ((rtx, int, int, FILE *));
#endif
extern void cse_end_of_basic_block  PARAMS ((rtx,
            struct cse_basic_block_data *,
            int, int, int));

/* In jump.c */
extern int comparison_dominates_p PARAMS ((enum rtx_code, enum rtx_code));
extern int condjump_p     PARAMS ((rtx));
extern int any_condjump_p   PARAMS ((rtx));
extern int any_uncondjump_p   PARAMS ((rtx));
extern int safe_to_remove_jump_p  PARAMS ((rtx));
extern rtx pc_set     PARAMS ((rtx));
extern rtx condjump_label   PARAMS ((rtx));
extern int simplejump_p     PARAMS ((rtx));
extern int tablejump_p      PARAMS ((rtx));
extern int returnjump_p     PARAMS ((rtx));
extern int onlyjump_p     PARAMS ((rtx));
extern int only_sets_cc0_p    PARAMS ((rtx));
extern int sets_cc0_p     PARAMS ((rtx));
extern int invert_jump_1    PARAMS ((rtx, rtx));
extern int invert_jump      PARAMS ((rtx, rtx, int));
extern int rtx_renumbered_equal_p PARAMS ((rtx, rtx));
extern int true_regnum      PARAMS ((rtx));
extern unsigned int reg_or_subregno PARAMS ((rtx));
extern int redirect_jump_1    PARAMS ((rtx, rtx));
extern int redirect_jump    PARAMS ((rtx, rtx, int));
extern void rebuild_jump_labels   PARAMS ((rtx));
extern enum rtx_code reversed_comparison_code PARAMS ((rtx, rtx));
extern enum rtx_code reversed_comparison_code_parts PARAMS ((enum rtx_code,
                   rtx, rtx, rtx));
extern void delete_for_peephole   PARAMS ((rtx, rtx));
extern int condjump_in_parallel_p PARAMS ((rtx));
extern void never_reached_warning PARAMS ((rtx, rtx));
extern void purge_line_number_notes PARAMS ((rtx));
extern void copy_loop_headers   PARAMS ((rtx));

/* In emit-rtl.c.  */
extern int max_reg_num        PARAMS ((void));
extern int max_label_num      PARAMS ((void));
extern int get_first_label_num      PARAMS ((void));
extern void delete_insns_since      PARAMS ((rtx));
extern void mark_reg_pointer      PARAMS ((rtx, int));
extern void mark_user_reg     PARAMS ((rtx));
extern void reset_used_flags      PARAMS ((rtx));
extern void reorder_insns     PARAMS ((rtx, rtx, rtx));
extern void reorder_insns_nobb      PARAMS ((rtx, rtx, rtx));
extern int get_max_uid        PARAMS ((void));
extern int in_sequence_p      PARAMS ((void));
extern void force_next_line_note    PARAMS ((void));
extern void init_emit       PARAMS ((void));
extern void init_emit_once      PARAMS ((int));
extern void push_topmost_sequence   PARAMS ((void));
extern void pop_topmost_sequence    PARAMS ((void));
extern int subreg_realpart_p      PARAMS ((rtx));
extern void reverse_comparison      PARAMS ((rtx));
extern void set_new_first_and_last_insn   PARAMS ((rtx, rtx));
extern void set_new_first_and_last_label_num  PARAMS ((int, int));
extern void set_new_last_label_num    PARAMS ((int));
extern void unshare_all_rtl_again   PARAMS ((rtx));
extern void set_first_insn      PARAMS ((rtx));
extern void set_last_insn     PARAMS ((rtx));
extern void link_cc0_insns      PARAMS ((rtx));
extern void add_insn        PARAMS ((rtx));
extern void add_insn_before     PARAMS ((rtx, rtx));
extern void add_insn_after      PARAMS ((rtx, rtx));
extern void remove_insn       PARAMS ((rtx));
extern void reorder_insns_with_line_notes PARAMS ((rtx, rtx, rtx));
extern void emit_insn_after_with_line_notes PARAMS ((rtx, rtx, rtx));
extern enum rtx_code classify_insn    PARAMS ((rtx));
extern rtx emit         PARAMS ((rtx));
/* Query and clear/ restore no_line_numbers.  This is used by the
   switch / case handling in stmt.c to give proper line numbers in
   warnings about unreachable code.  */
int force_line_numbers PARAMS ((void));
void restore_line_number_status PARAMS ((int old_value));
extern void renumber_insns                      PARAMS ((FILE *));
extern void remove_unnecessary_notes             PARAMS ((void));
extern rtx delete_insn      PARAMS ((rtx));
extern void delete_insn_chain   PARAMS ((rtx, rtx));
extern rtx delete_insn_and_edges  PARAMS ((rtx));
extern void delete_insn_chain_and_edges PARAMS ((rtx, rtx));

/* In combine.c */
extern int combine_instructions   PARAMS ((rtx, unsigned int));
extern unsigned int extended_count  PARAMS ((rtx, enum machine_mode, int));
extern rtx remove_death     PARAMS ((unsigned int, rtx));
#ifdef BUFSIZ
extern void dump_combine_stats    PARAMS ((FILE *));
extern void dump_combine_total_stats  PARAMS ((FILE *));
#endif

/* In sched.c.  */
#ifdef BUFSIZ
extern void schedule_insns    PARAMS ((FILE *));
extern void schedule_ebbs   PARAMS ((FILE *));
#endif
extern void fix_sched_param   PARAMS ((const char *, const char *));

/* In print-rtl.c */
extern const char *print_rtx_head;
extern void debug_rtx     PARAMS ((rtx));
extern void debug_rtx_list    PARAMS ((rtx, int));
extern void debug_rtx_range   PARAMS ((rtx, rtx));
extern rtx debug_rtx_find   PARAMS ((rtx, int));
#ifdef BUFSIZ
extern void print_mem_expr    PARAMS ((FILE *, tree));
extern void print_rtl     PARAMS ((FILE *, rtx));
extern void print_simple_rtl    PARAMS ((FILE *, rtx));
extern int print_rtl_single   PARAMS ((FILE *, rtx));
extern void print_inline_rtx    PARAMS ((FILE *, rtx, int));
#endif

/* In loop.c */
extern void init_loop     PARAMS ((void));
extern rtx libcall_other_reg    PARAMS ((rtx, rtx));
#ifdef BUFSIZ
extern void loop_optimize   PARAMS ((rtx, FILE *, int));
#endif
extern void record_excess_regs    PARAMS ((rtx, rtx, rtx *));

/* In function.c */
extern void reposition_prologue_and_epilogue_notes  PARAMS ((rtx));
extern void thread_prologue_and_epilogue_insns    PARAMS ((rtx));
extern int prologue_epilogue_contains     PARAMS ((rtx));
extern int sibcall_epilogue_contains      PARAMS ((rtx));
extern void preserve_rtl_expr_result      PARAMS ((rtx));
extern void mark_temp_addr_taken      PARAMS ((rtx));
extern void update_temp_slot_address      PARAMS ((rtx, rtx));
extern void purge_addressof       PARAMS ((rtx));
extern void purge_hard_subreg_sets      PARAMS ((rtx));

/* In stmt.c */
extern void set_file_and_line_for_stmt  PARAMS ((const char *, int));
extern void expand_null_return    PARAMS ((void));
extern void emit_jump     PARAMS ((rtx));
extern int preserve_subexpressions_p  PARAMS ((void));

/* In expr.c */
extern rtx move_by_pieces   PARAMS ((rtx, rtx,
             unsigned HOST_WIDE_INT,
             unsigned int, int));

/* In flow.c */
extern void recompute_reg_usage     PARAMS ((rtx, int));
extern int initialize_uninitialized_subregs PARAMS ((void));
extern void delete_dead_jumptables    PARAMS ((void));
#ifdef BUFSIZ
extern void print_rtl_with_bb     PARAMS ((FILE *, rtx));
extern void dump_flow_info      PARAMS ((FILE *));
#endif

/* In expmed.c */
extern void init_expmed     PARAMS ((void));
extern void expand_inc      PARAMS ((rtx, rtx));
extern void expand_dec      PARAMS ((rtx, rtx));
extern rtx expand_mult_highpart   PARAMS ((enum machine_mode, rtx,
            unsigned HOST_WIDE_INT, rtx,
            int, int));

/* In gcse.c */
#ifdef BUFSIZ
extern int gcse_main      PARAMS ((rtx, FILE *));
#endif

/* In global.c */
extern void mark_elimination    PARAMS ((int, int));
#ifdef BUFSIZ
extern int global_alloc     PARAMS ((FILE *));
extern void dump_global_regs    PARAMS ((FILE *));
#endif
#ifdef HARD_CONST
/* Yes, this ifdef is silly, but HARD_REG_SET is not always defined.  */
extern void retry_global_alloc    PARAMS ((int, HARD_REG_SET));
#endif
extern void build_insn_chain    PARAMS ((rtx));

/* In regclass.c */
extern int reg_classes_intersect_p  PARAMS ((enum reg_class, enum reg_class));
extern int reg_class_subset_p   PARAMS ((enum reg_class, enum reg_class));
extern void globalize_reg   PARAMS ((int));
extern void init_regs     PARAMS ((void));
extern void init_fake_stack_mems  PARAMS ((void));
extern void init_reg_sets   PARAMS ((void));
extern void regset_release_memory PARAMS ((void));
extern void regclass_init   PARAMS ((void));
extern void regclass      PARAMS ((rtx, int, FILE *));
extern void reg_scan      PARAMS ((rtx, unsigned int, int));
extern void reg_scan_update   PARAMS ((rtx, rtx, unsigned int));
extern void fix_register    PARAMS ((const char *, int, int));
#ifdef HARD_CONST
extern void cannot_change_mode_set_regs PARAMS ((HARD_REG_SET *,
             enum machine_mode,
             unsigned int));
#endif
extern bool invalid_mode_change_p PARAMS ((unsigned int,
             enum reg_class,
             enum machine_mode));

extern int delete_null_pointer_checks PARAMS ((rtx));

/* In regmove.c */
#ifdef BUFSIZ
extern void regmove_optimize    PARAMS ((rtx, int, FILE *));
#endif
extern void combine_stack_adjustments PARAMS ((void));

/* In reorg.c */
#ifdef BUFSIZ
extern void dbr_schedule    PARAMS ((rtx, FILE *));
#endif

/* In local-alloc.c */
#ifdef BUFSIZ
extern void dump_local_alloc    PARAMS ((FILE *));
#endif
extern int local_alloc      PARAMS ((void));
extern int function_invariant_p   PARAMS ((rtx));

/* In profile.c */
extern void init_branch_prob    PARAMS ((const char *));
extern void branch_prob     PARAMS ((void));
extern void end_branch_prob   PARAMS ((void));
extern void output_func_start_profiler  PARAMS ((void));

/* In reg-stack.c */
#ifdef BUFSIZ
extern void reg_to_stack    PARAMS ((rtx, FILE *));
#endif

/* In fold-const.c */
extern int add_double   PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *));
extern int neg_double   PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *));
extern int mul_double   PARAMS ((unsigned HOST_WIDE_INT,
           HOST_WIDE_INT,
           unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *));
extern void lshift_double PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           HOST_WIDE_INT, unsigned int,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *, int));
extern void rshift_double PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           HOST_WIDE_INT, unsigned int,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *, int));
extern void lrotate_double  PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           HOST_WIDE_INT, unsigned int,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *));
extern void rrotate_double  PARAMS ((unsigned HOST_WIDE_INT, HOST_WIDE_INT,
           HOST_WIDE_INT, unsigned int,
           unsigned HOST_WIDE_INT *,
           HOST_WIDE_INT *));

/* In calls.c */
enum libcall_type
{
  LCT_NORMAL = 0,
  LCT_CONST = 1,
  LCT_PURE = 2,
  LCT_CONST_MAKE_BLOCK = 3,
  LCT_PURE_MAKE_BLOCK = 4,
  LCT_NORETURN = 5,
  LCT_THROW = 6,
  LCT_ALWAYS_RETURN = 7,
  LCT_RETURNS_TWICE = 8
};

extern void emit_library_call   PARAMS ((rtx, enum libcall_type,
             enum machine_mode, int,
             ...));
extern rtx emit_library_call_value  PARAMS ((rtx, rtx, enum libcall_type,
             enum machine_mode, int,
             ...));

/* In unroll.c */
extern int set_dominates_use    PARAMS ((int, int, int, rtx, rtx));

/* In varasm.c */
extern int in_data_section    PARAMS ((void));
extern void init_varasm_once    PARAMS ((void));

/* In rtl.c */
extern void init_rtl      PARAMS ((void));
extern void traverse_md_constants PARAMS ((int (*) (void **, void *),
             void *));
struct md_constant { char *name, *value; };

#ifdef BUFSIZ
extern int read_skip_spaces   PARAMS ((FILE *));
extern rtx read_rtx     PARAMS ((FILE *));
#endif

extern const char *read_rtx_filename;
extern int read_rtx_lineno;

/* Redefine abort to report an internal error w/o coredump, and
   reporting the location of the error in the source file.  This logic
   is duplicated in rtl.h and tree.h because every file that needs the
   special abort includes one or both.  toplev.h gets too few files,
   system.h gets too many.  */

extern void fancy_abort PARAMS ((const char *, int, const char *))
    ATTRIBUTE_NORETURN;
#define abort() fancy_abort (__FILE__, __LINE__, __FUNCTION__)

/* In alias.c */
extern void clear_reg_alias_info  PARAMS ((rtx));
extern rtx canon_rtx                    PARAMS ((rtx));
extern int true_dependence    PARAMS ((rtx, enum machine_mode, rtx,
            int (*)(rtx, int)));
extern rtx get_addr                     PARAMS ((rtx));
extern int canon_true_dependence        PARAMS ((rtx, enum machine_mode, rtx,
                                                rtx, int (*)(rtx, int)));
extern int read_dependence    PARAMS ((rtx, rtx));
extern int anti_dependence    PARAMS ((rtx, rtx));
extern int output_dependence    PARAMS ((rtx, rtx));
extern void mark_constant_function  PARAMS ((void));
extern void init_alias_once   PARAMS ((void));
extern void init_alias_analysis   PARAMS ((void));
extern void end_alias_analysis    PARAMS ((void));
extern rtx addr_side_effect_eval  PARAMS ((rtx, int, int));

/* In sibcall.c */
typedef enum {
  sibcall_use_normal = 1,
  sibcall_use_tail_recursion,
  sibcall_use_sibcall
} sibcall_use_t;

extern void optimize_sibling_and_tail_recursive_calls PARAMS ((void));
extern void replace_call_placeholder  PARAMS ((rtx, sibcall_use_t));

#ifdef STACK_REGS
extern int stack_regs_mentioned   PARAMS ((rtx insn));
#endif

/* In toplev.c */
extern GTY(()) rtx stack_limit_rtx;

/* In regrename.c */
extern void regrename_optimize    PARAMS ((void));
extern void copyprop_hardreg_forward  PARAMS ((void));

/* In ifcvt.c */
extern void if_convert      PARAMS ((int));

/* In predict.c */
extern void invert_br_probabilities PARAMS ((rtx));
extern bool expensive_function_p  PARAMS ((int));
/* In tracer.c */
extern void tracer      PARAMS ((void));

#endif /* ! GCC_RTL_H */

---