m68k.h

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    || ((CLASS2) == FPA_REGS && (CLASS1) != FPA_REGS))	\
   ? 4 : 2)

#endif /* define SUPPORT_SUN_FPA */

/* Stack layout; function entry, exit and calling.  */

/* Define this if pushing a word on the stack
   makes the stack pointer a smaller address.  */
#define STACK_GROWS_DOWNWARD

/* Nonzero if we need to generate stack-probe insns.
   On most systems they are not needed.
   When they are needed, define this as the stack offset to probe at.  */
#define NEED_PROBE 0

/* Define this if the nominal address of the stack frame
   is at the high-address end of the local variables;
   that is, each additional local variable allocated
   goes at a more negative offset in the frame.  */
#define FRAME_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 we generate an insn to push BYTES bytes,
   this says how many the stack pointer really advances by.
   On the 68000, sp@- in a byte insn really pushes a word.  */
#define PUSH_ROUNDING(BYTES) (((BYTES) + 1) & ~1)

/* Offset of first parameter from the argument pointer register value.  */
#define FIRST_PARM_OFFSET(FNDECL) 8

/* 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 68000, the RTS insn cannot pop anything.
   On the 68010, the RTD insn may be used to pop them if the number
     of args is fixed, but if the number is variable then the caller
     must pop them all.  RTD can't be used for library calls now
     because the library is compiled with the Unix compiler.
   Use of RTD is a selectable option, since it is incompatible with
   standard Unix calling sequences.  If the option is not selected,
   the caller must always pop the args.  */

#define RETURN_POPS_ARGS(FUNTYPE,SIZE)   \
  ((TARGET_RTD && TREE_CODE (FUNTYPE) != IDENTIFIER_NODE	\
    && (TYPE_ARG_TYPES (FUNTYPE) == 0				\
	|| (TREE_VALUE (tree_last (TYPE_ARG_TYPES (FUNTYPE)))	\
	    == void_type_node)))				\
   ? (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.  */

/* On the 68000 the return value is in D0 regardless.  */

#define FUNCTION_VALUE(VALTYPE, FUNC)  \
  gen_rtx (REG, TYPE_MODE (VALTYPE), 0)

/* Define how to find the value returned by a library function
   assuming the value has mode MODE.  */

/* On the 68000 the return value is in D0 regardless.  */

#define LIBCALL_VALUE(MODE)  gen_rtx (REG, MODE, 0)

/* 1 if N is a possible register number for a function value.
   On the 68000, d0 is the only register thus used.  */

#define FUNCTION_VALUE_REGNO_P(N) ((N) == 0)

/* Define this if PCC uses the nonreentrant convention for returning
   structure and union values.  */

#define PCC_STATIC_STRUCT_RETURN

/* 1 if N is a possible register number for function argument passing.
   On the 68000, no registers are used in this way.  */

#define FUNCTION_ARG_REGNO_P(N) 0

/* 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 the m68k, this is a single integer, which is a number of bytes
   of arguments scanned so far.  */

#define CUMULATIVE_ARGS int

/* 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 the m68k, the offset starts at 0.  */

#define INIT_CUMULATIVE_ARGS(CUM,FNTYPE,LIBNAME)	\
 ((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) += ((MODE) != BLKmode			\
	    ? (GET_MODE_SIZE (MODE) + 3) & ~3	\
	    : (int_size_in_bytes (TYPE) + 3) & ~3))

/* Define where to put the arguments to a function.
   Value is zero to push the argument on the stack,
   or a hard register in which to store the argument.

   MODE is the argument's machine mode.
   TYPE is the data type of the argument (as a tree).
    This is null for libcalls where that information may
    not be available.
   CUM is a variable of type CUMULATIVE_ARGS which gives info about
    the preceding args and about the function being called.
   NAMED is nonzero if this argument is a named parameter
    (otherwise it is an extra parameter matching an ellipsis).  */

/* On the 68000 all args are pushed, except if -mregparm is specified
   then the first two words of arguments are passed in d0, d1.
   *NOTE* -mregparm does not work.
   It exists only to test register calling conventions.  */

#define FUNCTION_ARG(CUM, MODE, TYPE, NAMED) \
((TARGET_REGPARM && (CUM) < 8) ? gen_rtx (REG, (MODE), (CUM) / 4) : 0)

/* For an arg passed partly in registers and partly in memory,
   this is the number of registers used.
   For args passed entirely in registers or entirely in memory, zero.  */

#define FUNCTION_ARG_PARTIAL_NREGS(CUM, MODE, TYPE, NAMED) \
((TARGET_REGPARM && (CUM) < 8					\
  && 8 < ((CUM) + ((MODE) == BLKmode				\
		      ? int_size_in_bytes (TYPE)		\
		      : GET_MODE_SIZE (MODE))))  		\
 ? 2 - (CUM) / 4 : 0)

/* Generate the assembly code for function entry. */
#define FUNCTION_PROLOGUE(FILE, SIZE) output_function_prologue(FILE, SIZE)

/* Output assembler code to FILE to increment profiler label # LABELNO
   for profiling a function entry.  */

#define FUNCTION_PROFILER(FILE, LABELNO)  \
  asm_fprintf (FILE, "\tlea %LLP%d,%Ra0\n\tjsr mcount\n", (LABELNO))

/* Output assembler code to FILE to initialize this source file's
   basic block profiling info, if that has not already been done.  */

#define FUNCTION_BLOCK_PROFILER(FILE, LABELNO)  \
  asm_fprintf (FILE, "\ttstl %LLPBX0\n\tbne %LLPI%d\n\tpea %LLPBX0\n\tjsr %U__bb_init_func\n\taddql %I4,%Rsp\n%LLPI%d:\n",  \
	   LABELNO, LABELNO);

/* Output assembler code to FILE to increment the entry-count for
   the BLOCKNO'th basic block in this source file.  */

#define BLOCK_PROFILER(FILE, BLOCKNO)	\
  asm_fprintf (FILE, "\taddql %I1,%LLPBX2+%d\n", 4 * BLOCKNO)

/* 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 1

/* Generate the assembly code for function exit. */
#define FUNCTION_EPILOGUE(FILE, SIZE) output_function_epilogue (FILE, SIZE)
  
/* This is a hook for other tm files to change.  */
/* #define FUNCTION_EXTRA_EPILOGUE(FILE, SIZE) */

/* Determine if the epilogue should be output as RTL.
   You should override this if you define FUNCTION_EXTRA_EPILOGUE.  */
#define USE_RETURN_INSN use_return_insn ()

/* Store in the variable DEPTH the initial difference between the
   frame pointer reg contents and the stack pointer reg contents,
   as of the start of the function body.  This depends on the layout
   of the fixed parts of the stack frame and on how registers are saved.

   On the 68k, if we have a frame, we must add one word to its length
   to allow for the place that a6 is stored when we do have a frame pointer.
   Otherwise, we would need to compute the offset from the frame pointer
   of a local variable as a function of frame_pointer_needed, which
   is hard.  */

#define INITIAL_FRAME_POINTER_OFFSET(DEPTH)			\
{ int regno;							\
  int offset = -4;						\
  for (regno = 16; regno < FIRST_PSEUDO_REGISTER; regno++)	\
    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
      offset += 12;						\
  for (regno = 0; regno < 16; regno++)				\
    if (regs_ever_live[regno] && ! call_used_regs[regno])	\
      offset += 4;						\
  (DEPTH) = (offset + ((get_frame_size () + 3) & -4)		\
	     + (get_frame_size () == 0 ? 0 : 4));		\
}

/* Output assembler code for a block containing the constant parts
   of a trampoline, leaving space for the variable parts.  */

/* On the 68k, the trampoline looks like this:
     mov  @#.,a0
     jsr  @#___trampoline
     jsr  @#___trampoline
     .long STATIC
     .long FUNCTION
The reason for having three jsr insns is so that an entire line
of the instruction cache is filled in a predictable way
that will always be the same.

We always use the assembler label ___trampoline
regardless of whether the system adds underscores.  */

#define TRAMPOLINE_TEMPLATE(FILE)					\
{									\
  ASM_OUTPUT_SHORT (FILE, gen_rtx (CONST_INT, VOIDmode, 0x207c));	\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
  ASM_OUTPUT_SHORT (FILE, gen_rtx (CONST_INT, VOIDmode, 0x4eb9));	\
  ASM_OUTPUT_INT (FILE, gen_rtx (SYMBOL_REF, SImode, "*___trampoline"));\
  ASM_OUTPUT_SHORT (FILE, gen_rtx (CONST_INT, VOIDmode, 0x4eb9));	\
  ASM_OUTPUT_INT (FILE, gen_rtx (SYMBOL_REF, SImode, "*___trampoline"));\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
  ASM_OUTPUT_SHORT (FILE, const0_rtx);					\
}

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

#define TRAMPOLINE_SIZE 26

/* Alignment required for a trampoline.  16 is used to find the
   beginning of a line in the instruction cache.  */

#define TRAMPOLINE_ALIGN 16

/* 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, 2)), TRAMP); \
  emit_move_insn (gen_rtx (MEM, SImode, plus_constant (TRAMP, 18)), CXT); \
  emit_move_insn (gen_rtx (MEM, SImode, plus_constant (TRAMP, 22)), FNADDR); \
}

/* This is the library routine that is used
   to transfer control from the trampoline
   to the actual nested function.  */

/* A colon is used with no explicit operands
   to cause the template string to be scanned for %-constructs.  */
/* The function name __transfer_from_trampoline is not actually used.
   The function definition just permits use of "asm with operands"
   (though the operand list is empty).  */
#define TRANSFER_FROM_TRAMPOLINE				\
void								\
__transfer_from_trampoline ()					\
{								\
  register char *a0 asm ("%a0");				\
  asm (GLOBAL_ASM_OP " ___trampoline");				\
  asm ("___trampoline:");					\
  asm volatile ("move%.l %0,%@" : : "m" (a0[22]));		\
  asm volatile ("move%.l %1,%0" : "=a" (a0) : "m" (a0[18]));	\
  asm ("rts":);							\
}

/* Addressing modes, and classification of registers for them.  */

#define HAVE_POST_INCREMENT
/* #define HAVE_POST_DECREMENT */

#define HAVE_PRE_DECREMENT
/* #define HAVE_PRE_INCREMENT */

/* 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_INDEX_P(REGNO) \
((REGNO) < 16 || (unsigned) reg_renumber[REGNO] < 16)
#define REGNO_OK_FOR_BASE_P(REGNO) \
(((REGNO) ^ 010) < 8 || (unsigned) (reg_renumber[REGNO] ^ 010) < 8)
#define REGNO_OK_FOR_DATA_P(REGNO) \
((REGNO) < 8 || (unsigned) reg_renumber[REGNO] < 8)
#define REGNO_OK_FOR_FP_P(REGNO) \
(((REGNO) ^ 020) < 8 || (unsigned) (reg_renumber[REGNO] ^ 020) < 8)
#ifdef SUPPORT_SUN_FPA
#define REGNO_OK_FOR_FPA_P(REGNO) \
(((REGNO) >= 24 && (REGNO) < 56) || (reg_renumber[REGNO] >= 24 && reg_renumber[REGNO] < 56))
#endif

/* Now macros that check whether X is a register and also,
   strictly, whether it is in a specified class.

   These macros are specific to the 68000, and may be used only
   in code for printing assembler insns and in conditions for
   define_optimization.  */

/* 1 if X is a data register.  */

#define DATA_REG_P(X) (REG_P (X) && REGNO_OK_FOR_DATA_P (REGNO (X)))

/* 1 if X is an fp register.  */

#define FP_REG_P(X) (REG_P (X) && REGNO_OK_FOR_FP_P (REGNO (X)))

/* 1 if X is an address register  */

#define ADDRESS_REG_P(X) (REG_P (X) && REGNO_OK_FOR_BASE_P (REGNO (X)))

#ifdef SUPPORT_SUN_FPA
/* 1 if X is a register in the Sun FPA.  */
#define FPA_REG_P(X) (REG_P (X) && REGNO_OK_FOR_FPA_P (REGNO (X)))
#else
/* Answer must be no if we don't have an FPA.  */
#define FPA_REG_P(X) 0
#endif

/* Maximum number of registers that can appear in a valid memory address.  */

#define MAX_REGS_PER_ADDRESS 2

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