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/* Definitions of target machine for GNU compiler,

   for Motorola M*CORE Processor.

   Copyright (C) 1993, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007

   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 3, 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 COPYING3.  If not see

   <http://www.gnu.org/licenses/>.  */

#ifndef GCC_MCORE_H

#define GCC_MCORE_H

/* RBE: need to move these elsewhere.  */

#undef  LIKE_PPC_ABI 

#define MCORE_STRUCT_ARGS

/* RBE: end of "move elsewhere".  */

/* Run-time Target Specification.  */

#define TARGET_MCORE

/* Get tree.c to declare a target-specific specialization of

   merge_decl_attributes.  */

#define TARGET_DLLIMPORT_DECL_ATTRIBUTES 1

#define TARGET_CPU_CPP_BUILTINS()                                         \

  do                                                                      \

    {                                                                     \

      builtin_define ("__mcore__");                                       \

      builtin_define ("__MCORE__");                                       \

      if (TARGET_LITTLE_END)                                              \

        builtin_define ("__MCORELE__");                                   \

      else                                                                \

        builtin_define ("__MCOREBE__");                                   \

      if (TARGET_M340)                                                    \

        builtin_define ("__M340__");                                      \

      else                                                                \

        builtin_define ("__M210__");                                      \

    }                                                                     \

  while (0)

/* If -m4align is ever re-enabled then add this line to the definition of CPP_SPEC

   %{!m4align:-D__MCORE_ALIGN_8__} %{m4align:-D__MCORE__ALIGN_4__}.  */

#undef  CPP_SPEC

#define CPP_SPEC "%{m210:%{mlittle-endian:%ethe m210 does not have little endian support}}"

/* We don't have a -lg library, so don't put it in the list.  */

#undef  LIB_SPEC

#define LIB_SPEC "%{!shared: %{!p:%{!pg:-lc}}%{p:-lc_p}%{pg:-lc_p}}"

#undef  ASM_SPEC

#define ASM_SPEC "%{mbig-endian:-EB} %{m210:-cpu=210 -EB}"

#undef  LINK_SPEC

#define LINK_SPEC "%{mbig-endian:-EB} %{m210:-EB} -X"

#define TARGET_DEFAULT  \

  (MASK_HARDLIT         \

   | MASK_8ALIGN        \

   | MASK_DIV           \

   | MASK_RELAX_IMM     \

   | MASK_M340          \

   | MASK_LITTLE_END)

#ifndef MULTILIB_DEFAULTS

#define MULTILIB_DEFAULTS { "mlittle-endian", "m340" }

#endif

/* The ability to have 4 byte alignment is being suppressed for now.

   If this ability is reenabled, you must disable the definition below

   *and* edit t-mcore to enable multilibs for 4 byte alignment code.  */

#undef TARGET_8ALIGN

#define TARGET_8ALIGN 1

extern char * mcore_current_function_name;

/* The MCore ABI says that bitfields are unsigned by default.  */

#define CC1_SPEC "-funsigned-bitfields"

/* What options are we going to default to specific settings when

   -O* happens; the user can subsequently override these settings.

   Omitting the frame pointer is a very good idea on the MCore.

   Scheduling isn't worth anything on the current MCore implementation.  */

#define OPTIMIZATION_OPTIONS(LEVEL,SIZE)        \

{                                               \

  if (LEVEL)                                    \

    {                                           \

      flag_no_function_cse = 1;                 \

      flag_omit_frame_pointer = 1;              \

                                                \

      if (LEVEL >= 2)                           \

        {                                       \

          flag_caller_saves = 0;         \

          flag_schedule_insns = 0;               \

          flag_schedule_insns_after_reload = 0;  \

        }                                       \

    }                                           \

  if (SIZE)                                     \

    {                                           \

      target_flags &= ~MASK_HARDLIT;            \

    }                                           \

}

/* What options are we going to force to specific settings,

   regardless of what the user thought he wanted.

   We also use this for some post-processing of options.  */

#define OVERRIDE_OPTIONS  mcore_override_options ()

/* Target machine storage Layout.  */

#define PROMOTE_MODE(MODE,UNSIGNEDP,TYPE)       \

  if (GET_MODE_CLASS (MODE) == MODE_INT         \

      && GET_MODE_SIZE (MODE) < UNITS_PER_WORD) \

    {                                           \

      (MODE) = SImode;                          \

      (UNSIGNEDP) = 1;                          \

    }

/* Define this if most significant bit is lowest numbered

   in instructions that operate on numbered bit-fields.  */

#define BITS_BIG_ENDIAN  0

/* Define this if most significant byte of a word is the lowest numbered.  */

#define BYTES_BIG_ENDIAN (! TARGET_LITTLE_END)

/* Define this if most significant word of a multiword number is the lowest

   numbered.  */

#define WORDS_BIG_ENDIAN (! TARGET_LITTLE_END)

#define LIBGCC2_WORDS_BIG_ENDIAN 1

#ifdef __MCORELE__

#undef  LIBGCC2_WORDS_BIG_ENDIAN

#define LIBGCC2_WORDS_BIG_ENDIAN 0

#endif

#define MAX_BITS_PER_WORD 32

/* Width of a word, in units (bytes).  */

#define UNITS_PER_WORD  4

/* A C expression for the size in bits of the type `long long' on the

   target machine.  If you don't define this, the default is two

   words.  */

#define LONG_LONG_TYPE_SIZE 64

/* Allocation boundary (in *bits*) for storing arguments in argument list.  */

#define PARM_BOUNDARY   32

/* Doubles must be aligned to an 8 byte boundary.  */

#define FUNCTION_ARG_BOUNDARY(MODE, TYPE) \

  ((MODE != BLKmode && (GET_MODE_SIZE (MODE) == 8)) \

   ? BIGGEST_ALIGNMENT : PARM_BOUNDARY)

/* Boundary (in *bits*) on which stack pointer should be aligned.  */

#define STACK_BOUNDARY  (TARGET_8ALIGN ? 64 : 32)

/* Largest increment in UNITS we allow the stack to grow in a single operation.  */

extern int mcore_stack_increment;

#define STACK_UNITS_MAXSTEP  4096

/* Allocation boundary (in *bits*) for the code of a function.  */

#define FUNCTION_BOUNDARY  ((TARGET_OVERALIGN_FUNC) ? 32 : 16)

/* Alignment of field after `int : 0' in a structure.  */

#define EMPTY_FIELD_BOUNDARY  32

/* No data type wants to be aligned rounder than this.  */

#define BIGGEST_ALIGNMENT  (TARGET_8ALIGN ? 64 : 32)

/* The best alignment to use in cases where we have a choice.  */

#define FASTEST_ALIGNMENT 32

/* Every structures size must be a multiple of 8 bits.  */

#define STRUCTURE_SIZE_BOUNDARY 8

/* Look at the fundamental type that is used for a bit-field and use

   that to impose alignment on the enclosing structure.

   struct s {int a:8}; should have same alignment as "int", not "char".  */

#define PCC_BITFIELD_TYPE_MATTERS       1

/* Largest integer machine mode for structures.  If undefined, the default

   is GET_MODE_SIZE(DImode).  */

#define MAX_FIXED_MODE_SIZE 32

/* Make strings word-aligned so strcpy from constants will be faster.  */

#define CONSTANT_ALIGNMENT(EXP, ALIGN)  \

  ((TREE_CODE (EXP) == STRING_CST       \

    && (ALIGN) < FASTEST_ALIGNMENT)     \

   ? FASTEST_ALIGNMENT : (ALIGN))

/* Make arrays of chars word-aligned for the same reasons.  */

#define DATA_ALIGNMENT(TYPE, ALIGN)             \

  (TREE_CODE (TYPE) == ARRAY_TYPE               \

   && TYPE_MODE (TREE_TYPE (TYPE)) == QImode    \

   && (ALIGN) < FASTEST_ALIGNMENT ? FASTEST_ALIGNMENT : (ALIGN))

/* Set this nonzero if move instructions will actually fail to work

   when given unaligned data.  */

#define STRICT_ALIGNMENT 1

/* Standard register usage.  */

/* Register allocation for our first guess

        r0              stack pointer

        r1              scratch, target reg for xtrb?

        r2-r7           arguments.

        r8-r14          call saved

        r15             link register

        ap              arg pointer (doesn't really exist, always eliminated)

        c               c bit

        fp              frame pointer (doesn't really exist, always eliminated)

        x19             two control registers.  */

/* Number of actual hardware registers.

   The hardware registers are assigned numbers for the compiler

   from 0 to just below FIRST_PSEUDO_REGISTER.

   All registers that the compiler knows about must be given numbers,

   even those that are not normally considered general registers.

   MCore has 16 integer registers and 2 control registers + the arg

   pointer.  */

#define FIRST_PSEUDO_REGISTER 20

#define R1_REG  1       /* Where literals are forced.  */

#define LK_REG  15      /* Overloaded on general register.  */

#define AP_REG  16      /* Fake arg pointer register.  */

/* RBE: mcore.md depends on CC_REG being set to 17.  */

#define CC_REG  17      /* Can't name it C_REG.  */

#define FP_REG  18      /* Fake frame pointer register.  */

/* Specify the registers used for certain standard purposes.

   The values of these macros are register numbers.  */

#undef PC_REGNUM /* Define this if the program counter is overloaded on a register.  */

#define STACK_POINTER_REGNUM 0 /* Register to use for pushing function arguments.  */

#define FRAME_POINTER_REGNUM 8 /* When we need FP, use r8.  */

/* The assembler's names for the registers.  RFP need not always be used as

   the Real framepointer; it can also be used as a normal general register.

   Note that the name `fp' is horribly misleading since `fp' is in fact only

   the argument-and-return-context pointer.  */

#define REGISTER_NAMES                                  \

{                                                       \

  "sp", "r1", "r2",  "r3",  "r4",  "r5",  "r6",  "r7",  \

  "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", \

  "apvirtual",  "c", "fpvirtual", "x19" \

}

/* 1 for registers that have pervasive standard uses

   and are not available for the register allocator.  */

#define FIXED_REGISTERS  \

 /*  r0  r1  r2  r3  r4  r5  r6  r7  r8  r9  r10 r11 r12 r13 r14 r15 ap  c  fp x19 */ \

   { 1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1, 1, 1}

/* 1 for registers not available across function calls.

   These must include the FIXED_REGISTERS and also any

   registers that can be used without being saved.

   The latter must include the registers where values are returned

   and the register where structure-value addresses are passed.

   Aside from that, you can include as many other registers as you like.  */

/* RBE: r15 {link register} not available across calls,

   But we don't mark it that way here....  */

#define CALL_USED_REGISTERS \

 /*  r0  r1  r2  r3  r4  r5  r6  r7  r8  r9  r10 r11 r12 r13 r14 r15 ap  c   fp x19 */ \

   { 1,  1,  1,  1,  1,  1,  1,  1,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  1, 1}

/* The order in which register should be allocated.  */

#define REG_ALLOC_ORDER  \

 /* r7  r6  r5  r4  r3  r2  r15 r14 r13 r12 r11 r10  r9  r8  r1  r0  ap  c   fp x19*/ \

  {  7,  6,  5,  4,  3,  2,  15, 14, 13, 12, 11, 10,  9,  8,  1,  0, 16, 17, 18, 19}

/* Return number of consecutive hard regs needed starting at reg REGNO

   to hold something of mode MODE.

   This is ordinarily the length in words of a value of mode MODE

   but can be less for certain modes in special long registers.

   On the MCore regs are UNITS_PER_WORD bits wide; */

#define HARD_REGNO_NREGS(REGNO, MODE)  \

   (((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD))

/* Value is 1 if hard register REGNO can hold a value of machine-mode MODE.

   We may keep double values in even registers.  */

#define HARD_REGNO_MODE_OK(REGNO, MODE)  \

  ((TARGET_8ALIGN && GET_MODE_SIZE (MODE) > UNITS_PER_WORD) ? (((REGNO) & 1) == 0) : (REGNO < 18))

/* Value is 1 if it is a good idea to tie two pseudo registers

   when one has mode MODE1 and one has mode MODE2.

   If HARD_REGNO_MODE_OK could produce different values for MODE1 and MODE2,

   for any hard reg, then this must be 0 for correct output.  */

#define MODES_TIEABLE_P(MODE1, MODE2) \

  ((MODE1) == (MODE2) || GET_MODE_CLASS (MODE1) == GET_MODE_CLASS (MODE2))

/* Value should be nonzero if functions must have frame pointers.

   Zero means the frame pointer need not be set up (and parms may be accessed

   via the stack pointer) in functions that seem suitable.  */

#define FRAME_POINTER_REQUIRED  0

/* Definitions for register eliminations.

   We have two registers that can be eliminated on the MCore.  First, the

   frame pointer register can often be eliminated in favor of the stack

   pointer register.  Secondly, the argument pointer register can always be

   eliminated; it is replaced with either the stack or frame pointer.  */

/* Base register for access to arguments of the function.  */

#define ARG_POINTER_REGNUM      16

/* Register in which the static-chain is passed to a function.  */

#define STATIC_CHAIN_REGNUM     1

/* This is an array of structures.  Each structure initializes one pair

   of eliminable registers.  The "from" register number is given first,

   followed by "to".  Eliminations of the same "from" register are listed

   in order of preference.  */

#define ELIMINABLE_REGS                         \

{{ FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}, \

 { ARG_POINTER_REGNUM,   STACK_POINTER_REGNUM}, \

 { ARG_POINTER_REGNUM,   FRAME_POINTER_REGNUM},}

/* Given FROM and TO register numbers, say whether this elimination

   is allowed.  */

#define CAN_ELIMINATE(FROM, TO) \

  (!((FROM) == FRAME_POINTER_REGNUM && FRAME_POINTER_REQUIRED))

/* Define the offset between two registers, one to be eliminated, and the other

   its replacement, at the start of a routine.  */

#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \

  OFFSET = mcore_initial_elimination_offset (FROM, TO)

/* Define the classes of registers for register constraints in the

   machine description.  Also define ranges of constants.

   One of the classes must always be named ALL_REGS and include all hard regs.

   If there is more than one class, another class must be named NO_REGS

   and contain no registers.

   The name GENERAL_REGS must be the name of a class (or an alias for

   another name such as ALL_REGS).  This is the class of registers

   that is allowed by "g" or "r" in a register constraint.

   Also, registers outside this class are allocated only when

   instructions express preferences for them.

   The classes must be numbered in nondecreasing order; that is,

   a larger-numbered class must never be contained completely

   in a smaller-numbered class.

   For any two classes, it is very desirable that there be another

   class that represents their union.  */

/* The MCore has only general registers. There are

   also some special purpose registers: the T bit register, the

   procedure Link and the Count Registers.  */

enum reg_class

{

  NO_REGS,

  ONLYR1_REGS,

  LRW_REGS,

  GENERAL_REGS,

  C_REGS,

  ALL_REGS,

  LIM_REG_CLASSES

};

#define N_REG_CLASSES  (int) LIM_REG_CLASSES

/* Give names of register classes as strings for dump file.  */

#define REG_CLASS_NAMES  \

{                       \

  "NO_REGS",            \

  "ONLYR1_REGS",        \

  "LRW_REGS",           \

  "GENERAL_REGS",       \

  "C_REGS",             \

  "ALL_REGS",           \

}

/* Define which registers fit in which classes.

   This is an initializer for a vector of HARD_REG_SET

   of length N_REG_CLASSES.  */

/* ??? STACK_POINTER_REGNUM should be excluded from LRW_REGS.  */

#define REG_CLASS_CONTENTS              \

{                                       \

  {0x000000},  /* NO_REGS       */      \

  {0x000002},  /* ONLYR1_REGS   */      \

  {0x007FFE},  /* LRW_REGS      */      \

  {0x01FFFF},  /* GENERAL_REGS  */      \

  {0x020000},  /* C_REGS        */      \

  {0x0FFFFF}   /* ALL_REGS      */      \

}

/* The same information, inverted:

   Return the class number of the smallest class containing

   reg number REGNO.  This could be a conditional expression

   or could index an array.  */

extern const int regno_reg_class[FIRST_PSEUDO_REGISTER];

#define REGNO_REG_CLASS(REGNO) regno_reg_class[REGNO]

/* When defined, the compiler allows registers explicitly used in the

   rtl to be used as spill registers but prevents the compiler from

   extending the lifetime of these registers.  */

#define SMALL_REGISTER_CLASSES 1

/* The class value for index registers, and the one for base regs.  */

#define INDEX_REG_CLASS  NO_REGS

#define BASE_REG_CLASS   GENERAL_REGS

/* Get reg_class from a letter such as appears in the machine

   description.  */

extern const enum reg_class reg_class_from_letter[];

#define REG_CLASS_FROM_LETTER(C) \

   (ISLOWER (C) ? reg_class_from_letter[(C) - 'a'] : NO_REGS)

/* The letters I, J, K, L, M, N, O, and P in a register constraint string

   can be used to stand for particular ranges of immediate operands.

   This macro defines what the ranges are.

   C is the letter, and VALUE is a constant value.

   Return 1 if VALUE is in the range specified by C.

        I: loadable by movi (0..127)

        J: arithmetic operand 1..32

        K: shift operand 0..31

        L: negative arithmetic operand -1..-32

        M: powers of two, constants loadable by bgeni

        N: powers of two minus 1, constants loadable by bmaski, including -1

        O: allowed by cmov with two constants +/- 1 of each other

        P: values we will generate 'inline' -- without an 'lrw'

   Others defined for use after reload

        Q: constant 1

        R: a label

        S: 0/1/2 cleared bits out of 32 [for bclri's]

        T: 2 set bits out of 32 [for bseti's]

        U: constant 0

        xxxS: 1 cleared bit out of 32 (complement of power of 2). for bclri

        xxxT: 2 cleared bits out of 32. for pairs of bclris.  */

#define CONST_OK_FOR_I(VALUE) (((int)(VALUE)) >= 0 && ((int)(VALUE)) <= 0x7f)

#define CONST_OK_FOR_J(VALUE) (((int)(VALUE)) >  0 && ((int)(VALUE)) <= 32)

#define CONST_OK_FOR_L(VALUE) (((int)(VALUE)) <  0 && ((int)(VALUE)) >= -32)

#define CONST_OK_FOR_K(VALUE) (((int)(VALUE)) >= 0 && ((int)(VALUE)) <= 31)

#define CONST_OK_FOR_M(VALUE) (exact_log2 (VALUE) >= 0)

#define CONST_OK_FOR_N(VALUE) (((int)(VALUE)) == -1 || exact_log2 ((VALUE) + 1) >= 0)

#define CONST_OK_FOR_O(VALUE) (CONST_OK_FOR_I(VALUE) || \

                               CONST_OK_FOR_M(VALUE) || \

                               CONST_OK_FOR_N(VALUE) || \

                               CONST_OK_FOR_M((int)(VALUE) - 1) || \

                               CONST_OK_FOR_N((int)(VALUE) + 1))

#define CONST_OK_FOR_P(VALUE) (mcore_const_ok_for_inline (VALUE)) 

#define CONST_OK_FOR_LETTER_P(VALUE, C)     \

     ((C) == 'I' ? CONST_OK_FOR_I (VALUE)   \

    : (C) == 'J' ? CONST_OK_FOR_J (VALUE)   \

    : (C) == 'L' ? CONST_OK_FOR_L (VALUE)   \

    : (C) == 'K' ? CONST_OK_FOR_K (VALUE)   \

    : (C) == 'M' ? CONST_OK_FOR_M (VALUE)   \

    : (C) == 'N' ? CONST_OK_FOR_N (VALUE)   \

    : (C) == 'P' ? CONST_OK_FOR_P (VALUE)   \

    : (C) == 'O' ? CONST_OK_FOR_O (VALUE)   \

    : 0)

/* Similar, but for floating constants, and defining letters G and H.

   Here VALUE is the CONST_DOUBLE rtx itself.  */

#define CONST_DOUBLE_OK_FOR_LETTER_P(VALUE, C) \

   ((C) == 'G' ? CONST_OK_FOR_I (CONST_DOUBLE_HIGH (VALUE)) \

              && CONST_OK_FOR_I (CONST_DOUBLE_LOW (VALUE))  \

    : 0)

/* Letters in the range `Q' through `U' in a register constraint string

   may be defined in a machine-dependent fashion to stand for arbitrary

   operand types.  */

#define EXTRA_CONSTRAINT(OP, C)                         \

  ((C) == 'R' ? (GET_CODE (OP) == MEM                   \

                 && GET_CODE (XEXP (OP, 0)) == LABEL_REF) \

   : (C) == 'S' ? (GET_CODE (OP) == CONST_INT \

                   && mcore_num_zeros (INTVAL (OP)) <= 2) \

   : (C) == 'T' ? (GET_CODE (OP) == CONST_INT \

                   && mcore_num_ones (INTVAL (OP)) == 2) \

   : (C) == 'Q' ? (GET_CODE (OP) == CONST_INT \

                   && INTVAL(OP) == 1) \

   : (C) == 'U' ? (GET_CODE (OP) == CONST_INT \

                   && INTVAL(OP) == 0) \

   : 0)

/* Given an rtx X being reloaded into a reg required to be

   in class CLASS, return the class of reg to actually use.

   In general this is just CLASS; but on some machines

   in some cases it is preferable to use a more restrictive class.  */

#define PREFERRED_RELOAD_CLASS(X, CLASS) mcore_reload_class (X, CLASS)

/* Return the register class of a scratch register needed to copy IN into

   or out of a register in CLASS in MODE.  If it can be done directly,

   NO_REGS is returned.  */

#define SECONDARY_RELOAD_CLASS(CLASS, MODE, X) \

  mcore_secondary_reload_class (CLASS, MODE, X)

/* Return the maximum number of consecutive registers

   needed to represent mode MODE in a register of class CLASS.

   On MCore this is the size of MODE in words.  */

#define CLASS_MAX_NREGS(CLASS, MODE)  \

     (ROUND_ADVANCE (GET_MODE_SIZE (MODE)))

/* Stack layout; function entry, exit and calling.  */

/* Define the number of register that can hold parameters.

   These two macros are used only in other macro definitions below.  */

#define NPARM_REGS 6

#define FIRST_PARM_REG 2

#define FIRST_RET_REG 2

/* Define this if pushing a word on the stack

   makes the stack pointer a smaller address.  */

#define STACK_GROWS_DOWNWARD  

/* Offset within stack frame to start allocating local variables at.

   If FRAME_GROWS_DOWNWARD, this is the offset to the END of the

   first local allocated.  Otherwise, it is the offset to the BEGINNING

   of the first local allocated.  */

#define STARTING_FRAME_OFFSET  0

/* If defined, the maximum amount of space required for outgoing arguments

   will be computed and placed into the variable

   `current_function_outgoing_args_size'.  No space will be pushed

   onto the stack for each call; instead, the function prologue should

   increase the stack frame size by this amount.  */

#define ACCUMULATE_OUTGOING_ARGS 1

/* Offset of first parameter from the argument pointer register value.  */

#define FIRST_PARM_OFFSET(FNDECL)  0

/* Value is the number of byte of arguments automatically

   popped when returning from a subroutine call.

   FUNTYPE is the data type of the function (as a tree),

   or for a library call it is an identifier node for the subroutine name.

   SIZE is the number of bytes of arguments passed on the stack.

   On the MCore, the callee does not pop any of its arguments that were passed

   on the stack.  */

#define RETURN_POPS_ARGS(FUNDECL,FUNTYPE,SIZE) 0

/* Define how to find the value returned by a function.

   VALTYPE is the data type of the value (as a tree).

   If the precise function being called is known, FUNC is its FUNCTION_DECL;

   otherwise, FUNC is 0.  */

#define FUNCTION_VALUE(VALTYPE, FUNC)  mcore_function_value (VALTYPE, FUNC)

/* Don't default to pcc-struct-return, because gcc is the only compiler, and

   we want to retain compatibility with older gcc versions.  */

#define DEFAULT_PCC_STRUCT_RETURN 0

/* Define how to find the value returned by a library function

   assuming the value has mode MODE.  */

#define LIBCALL_VALUE(MODE)  gen_rtx_REG (MODE, FIRST_RET_REG)

/* 1 if N is a possible register number for a function value.

   On the MCore, only r4 can return results.  */

#define FUNCTION_VALUE_REGNO_P(REGNO)  ((REGNO) == FIRST_RET_REG)

/* 1 if N is a possible register number for function argument passing.  */

#define FUNCTION_ARG_REGNO_P(REGNO)  \

  ((REGNO) >= FIRST_PARM_REG && (REGNO) < (NPARM_REGS + FIRST_PARM_REG))

/* Define a data type for recording info about an argument list

   during the scan of that argument list.  This data type should

   hold all necessary information about the function itself

   and about the args processed so far, enough to enable macros

   such as FUNCTION_ARG to determine where the next arg should go.

   On MCore, this is a single integer, which is a number of words

   of arguments scanned so far (including the invisible argument,

   if any, which holds the structure-value-address).

   Thus NARGREGS or more means all following args should go on the stack.  */

#define CUMULATIVE_ARGS  int

#define ROUND_ADVANCE(SIZE)     \

  ((SIZE + UNITS_PER_WORD - 1) / UNITS_PER_WORD)

/* Round a register number up to a proper boundary for an arg of mode

   MODE.

   We round to an even reg for things larger than a word.  */

#define ROUND_REG(X, MODE)                              \

  ((TARGET_8ALIGN                                       \

   && GET_MODE_UNIT_SIZE ((MODE)) > UNITS_PER_WORD)     \

   ? ((X) + ((X) & 1)) : (X))

/* Initialize a variable CUM of type CUMULATIVE_ARGS

   for a call to a function whose data type is FNTYPE.

   For a library call, FNTYPE is 0.

   On MCore, the offset always starts at 0: the first parm reg is always

   the same reg.  */

#define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \

  ((CUM) = 0)

/* Update the data in CUM to advance over an argument

   of mode MODE and data type TYPE.

   (TYPE is null for libcalls where that information may not be

   available.)  */

#define FUNCTION_ARG_ADVANCE(CUM, MODE, TYPE, NAMED)       \

 ((CUM) = (ROUND_REG ((CUM), (MODE))                       \

           + ((NAMED) * mcore_num_arg_regs (MODE, TYPE)))) \

/* Define where to put the arguments to a function.  */

#define FUNCTION_ARG(CUM, MODE, TYPE, NAMED) \

  mcore_function_arg (CUM, MODE, TYPE, NAMED)

/* Call the function profiler with a given profile label.  */

#define FUNCTION_PROFILER(STREAM,LABELNO)               \

{                                                       \

  fprintf (STREAM, "    trap    1\n");                  \

  fprintf (STREAM, "    .align  2\n");                  \

  fprintf (STREAM, "    .long   LP%d\n", (LABELNO));    \

}

/* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,

   the stack pointer does not matter.  The value is tested only in

   functions that have frame pointers.

   No definition is equivalent to always zero.  */

#define EXIT_IGNORE_STACK 0

/* Output assembler code for a block containing the constant parts

   of a trampoline, leaving space for the variable parts.

   On the MCore, the trampoline looks like:

        lrw     r1,  function

        lrw     r13, area

        jmp     r13

        or      r0, r0

    .literals                                                */

#define TRAMPOLINE_TEMPLATE(FILE)               \

{                                               \

  fprintf ((FILE), "    .short  0x7102\n");     \

  fprintf ((FILE), "    .short  0x7d02\n");     \

  fprintf ((FILE), "    .short  0x00cd\n");     \

  fprintf ((FILE), "    .short  0x1e00\n");     \

  fprintf ((FILE), "    .long   0\n");           \

  fprintf ((FILE), "    .long   0\n");           \

}

/* Length in units of the trampoline for entering a nested function.  */

#define TRAMPOLINE_SIZE  12

/* Alignment required for a trampoline in bits.  */

#define TRAMPOLINE_ALIGNMENT  32

/* Emit RTL insns to initialize the variable parts of a trampoline.

   FNADDR is an RTX for the address of the function's pure code.

   CXT is an RTX for the static chain value for the function.  */

#define INITIALIZE_TRAMPOLINE(TRAMP, FNADDR, CXT)  \

{                                                                       \

  emit_move_insn (gen_rtx_MEM (SImode, plus_constant ((TRAMP), 8)),     \

                  (CXT));                                               \

  emit_move_insn (gen_rtx_MEM (SImode, plus_constant ((TRAMP), 12)),    \

                  (FNADDR));                                            \

}

/* Macros to check register numbers against specific register classes.  */

/* These assume that REGNO is a hard or pseudo reg number.

   They give nonzero only if REGNO is a hard reg of the suitable class

   or a pseudo reg currently allocated to a suitable hard reg.

   Since they use reg_renumber, they are safe only once reg_renumber

   has been allocated, which happens in local-alloc.c.  */

#define REGNO_OK_FOR_BASE_P(REGNO)  \

  ((REGNO) < AP_REG || (unsigned) reg_renumber[(REGNO)] < AP_REG)

#define REGNO_OK_FOR_INDEX_P(REGNO)   0

/* Maximum number of registers that can appear in a valid memory

   address.  */

#define MAX_REGS_PER_ADDRESS 1

/* Recognize any constant value that is a valid address.  */

#define CONSTANT_ADDRESS_P(X)    (GET_CODE (X) == LABEL_REF)

/* Nonzero if the constant value X is a legitimate general operand.

   It is given that X satisfies CONSTANT_P or is a CONST_DOUBLE.

   On the MCore, allow anything but a double.  */

#define LEGITIMATE_CONSTANT_P(X) (GET_CODE(X) != CONST_DOUBLE)

/* The macros REG_OK_FOR..._P assume that the arg is a REG rtx

   and check its validity for a certain class.

   We have two alternate definitions for each of them.

   The usual definition accepts all pseudo regs; the other rejects

   them unless they have been allocated suitable hard regs.

   The symbol REG_OK_STRICT causes the latter definition to be used.  */

#ifndef REG_OK_STRICT

/* Nonzero if X is a hard reg that can be used as a base reg

   or if it is a pseudo reg.  */

#define REG_OK_FOR_BASE_P(X) \

        (REGNO (X) <= 16 || REGNO (X) >= FIRST_PSEUDO_REGISTER)

/* Nonzero if X is a hard reg that can be used as an index

   or if it is a pseudo reg.  */

#define REG_OK_FOR_INDEX_P(X)   0

#else

/* Nonzero if X is a hard reg that can be used as a base reg.  */

#define REG_OK_FOR_BASE_P(X)    \

        REGNO_OK_FOR_BASE_P (REGNO (X))

/* Nonzero if X is a hard reg that can be used as an index.  */

#define REG_OK_FOR_INDEX_P(X)   0

#endif

/* GO_IF_LEGITIMATE_ADDRESS recognizes an RTL expression

   that is a valid memory address for an instruction.

   The MODE argument is the machine mode for the MEM expression

   that wants to use this address.

   The other macros defined here are used only in GO_IF_LEGITIMATE_ADDRESS.  */

#define BASE_REGISTER_RTX_P(X)  \

  (GET_CODE (X) == REG && REG_OK_FOR_BASE_P (X))

#define INDEX_REGISTER_RTX_P(X)  \

  (GET_CODE (X) == REG && REG_OK_FOR_INDEX_P (X))

/* Jump to LABEL if X is a valid address RTX.  This must also take

   REG_OK_STRICT into account when deciding about valid registers, but it uses

   the above macros so we are in luck.

   Allow  REG

          REG+disp

   A legitimate index for a QI is 0..15, for HI is 0..30, for SI is 0..60,

   and for DI is 0..56 because we use two SI loads, etc.  */

#define GO_IF_LEGITIMATE_INDEX(MODE, REGNO, OP, LABEL)                  \

  do                                                                    \

    {                                                                   \

      if (GET_CODE (OP) == CONST_INT)                                   \

        {                                                               \

          if (GET_MODE_SIZE (MODE) >= 4                                 \

              && (((unsigned)INTVAL (OP)) % 4) == 0                      \

              &&  ((unsigned)INTVAL (OP)) <= 64 - GET_MODE_SIZE (MODE)) \

            goto LABEL;                                                 \

          if (GET_MODE_SIZE (MODE) == 2                                 \

              && (((unsigned)INTVAL (OP)) % 2) == 0                      \

              &&  ((unsigned)INTVAL (OP)) <= 30)                        \

            goto LABEL;                                                 \