rs6000.h

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  { 0x00000000, 0xffffffff, 0x00000000 },	/* FLOAT_REGS */	\
  { 0xffffffff, 0xffffffff, 0x00000008 },	/* NON_SPECIAL_REGS */	\
  { 0x00000000, 0x00000000, 0x00000001 },	/* MQ_REGS */		\
  { 0x00000000, 0x00000000, 0x00000002 },	/* LINK_REGS */		\
  { 0x00000000, 0x00000000, 0x00000004 },	/* CTR_REGS */		\
  { 0x00000000, 0x00000000, 0x00000006 },	/* LINK_OR_CTR_REGS */	\
  { 0x00000000, 0x00000000, 0x00000007 },	/* SPECIAL_REGS */	\
  { 0xffffffff, 0x00000000, 0x0000000f },	/* SPEC_OR_GEN_REGS */	\
  { 0x00000000, 0x00000000, 0x00000010 },	/* CR0_REGS */		\
  { 0x00000000, 0x00000000, 0x00000ff0 },	/* CR_REGS */		\
  { 0xffffffff, 0x00000000, 0x0000ffff },	/* NON_FLOAT_REGS */	\
  { 0x00000000, 0x00000000, 0x00010000 },	/* FPMEM_REGS */	\
  { 0x00000000, 0xffffffff, 0x00010000 },	/* FLOAT_OR_FPMEM_REGS */ \
  { 0xffffffff, 0xffffffff, 0x0001ffff }	/* 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.  */

#define REGNO_REG_CLASS(REGNO)		\
 ((REGNO) == 0 ? GENERAL_REGS		\
  : (REGNO) < 32 ? BASE_REGS		\
  : FP_REGNO_P (REGNO) ? FLOAT_REGS	\
  : (REGNO) == 68 ? CR0_REGS		\
  : CR_REGNO_P (REGNO) ? CR_REGS	\
  : (REGNO) == 64 ? MQ_REGS		\
  : (REGNO) == 65 ? LINK_REGS		\
  : (REGNO) == 66 ? CTR_REGS		\
  : (REGNO) == 67 ? BASE_REGS		\
  : (REGNO) == 76 ? FPMEM_REGS		\
  : NO_REGS)

/* The class value for index registers, and the one for base regs.  */
#define INDEX_REG_CLASS GENERAL_REGS
#define BASE_REG_CLASS BASE_REGS

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

#define REG_CLASS_FROM_LETTER(C) \
  ((C) == 'f' ? FLOAT_REGS	\
   : (C) == 'b' ? BASE_REGS	\
   : (C) == 'h' ? SPECIAL_REGS	\
   : (C) == 'q' ? MQ_REGS	\
   : (C) == 'c' ? CTR_REGS	\
   : (C) == 'l' ? LINK_REGS	\
   : (C) == 'x' ? CR0_REGS	\
   : (C) == 'y' ? CR_REGS	\
   : (C) == 'z' ? FPMEM_REGS	\
   : NO_REGS)

/* The letters I, J, K, L, M, N, 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' is a signed 16-bit constant
   `J' is a constant with only the high-order 16 bits non-zero
   `K' is a constant with only the low-order 16 bits non-zero
   `L' is a signed 16-bit constant shifted left 16 bits
   `M' is a constant that is greater than 31
   `N' is a constant that is an exact power of two
   `O' is the constant zero
   `P' is a constant whose negation is a signed 16-bit constant */

#define CONST_OK_FOR_LETTER_P(VALUE, C)					\
   ( (C) == 'I' ? (unsigned HOST_WIDE_INT) ((VALUE) + 0x8000) < 0x10000	\
   : (C) == 'J' ? ((VALUE) & (~ (HOST_WIDE_INT) 0xffff0000)) == 0	\
   : (C) == 'K' ? ((VALUE) & (~ (HOST_WIDE_INT) 0xffff)) == 0		\
   : (C) == 'L' ? (((VALUE) & 0xffff) == 0				\
		   && ((VALUE) >> 31 == -1 || (VALUE) >> 31 == 0))	\
   : (C) == 'M' ? (VALUE) > 31						\
   : (C) == 'N' ? exact_log2 (VALUE) >= 0				\
   : (C) == 'O' ? (VALUE) == 0						\
   : (C) == 'P' ? (unsigned HOST_WIDE_INT) ((- (VALUE)) + 0x8000) < 0x10000 \
   : 0)

/* Similar, but for floating constants, and defining letters G and H.
   Here VALUE is the CONST_DOUBLE rtx itself.

   We flag for special constants when we can copy the constant into
   a general register in two insns for DF/DI and one insn for SF.

   'H' is used for DI/DF constants that take 3 insns.  */

#define CONST_DOUBLE_OK_FOR_LETTER_P(VALUE, C)				\
  (  (C) == 'G' ? (num_insns_constant (VALUE, GET_MODE (VALUE))		\
		   == ((GET_MODE (VALUE) == SFmode) ? 1 : 2))		\
   : (C) == 'H' ? (num_insns_constant (VALUE, GET_MODE (VALUE)) == 3)	\
   : 0)

/* Optional extra constraints for this machine.

   'Q' means that is a memory operand that is just an offset from a reg.
   'R' is for AIX TOC entries.
   'S' is a constant that can be placed into a 64-bit mask operand
   'T' is a consatnt that can be placed into a 32-bit mask operand
   'U' is for V.4 small data references.  */

#define EXTRA_CONSTRAINT(OP, C)						\
  ((C) == 'Q' ? GET_CODE (OP) == MEM && GET_CODE (XEXP (OP, 0)) == REG	\
   : (C) == 'R' ? LEGITIMATE_CONSTANT_POOL_ADDRESS_P (OP)		\
   : (C) == 'S' ? mask64_operand (OP, VOIDmode)				\
   : (C) == 'T' ? mask_operand (OP, VOIDmode)				\
   : (C) == 'U' ? ((DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_SOLARIS) \
		   && small_data_operand (OP, GET_MODE (OP)))		\
   : 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.

   On the RS/6000, we have to return NO_REGS when we want to reload a
   floating-point CONST_DOUBLE to force it to be copied to memory.  */

#define PREFERRED_RELOAD_CLASS(X,CLASS)			\
  ((GET_CODE (X) == CONST_DOUBLE			\
    && GET_MODE_CLASS (GET_MODE (X)) == MODE_FLOAT)	\
   ? NO_REGS : (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,IN) \
  secondary_reload_class (CLASS, MODE, IN)

/* If we are copying between FP registers and anything else, we need a memory
   location.  */

#define SECONDARY_MEMORY_NEEDED(CLASS1,CLASS2,MODE) \
 ((CLASS1) != (CLASS2) && ((CLASS1) == FLOAT_REGS || (CLASS2) == FLOAT_REGS))

/* Return the maximum number of consecutive registers
   needed to represent mode MODE in a register of class CLASS.

   On RS/6000, this is the size of MODE in words,
   except in the FP regs, where a single reg is enough for two words.  */
#define CLASS_MAX_NREGS(CLASS, MODE)					\
 (((CLASS) == FLOAT_REGS || (CLASS) == FPMEM_REGS			\
   || (CLASS) == FLOAT_OR_FPMEM_REGS)					\
  ? ((GET_MODE_SIZE (MODE) + UNITS_PER_FP_WORD - 1) / UNITS_PER_FP_WORD) \
  : ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD))

/* If defined, gives a class of registers that cannot be used as the
   operand of a SUBREG that changes the size of the object.  */

#define CLASS_CANNOT_CHANGE_SIZE	FLOAT_OR_FPMEM_REGS

/* Stack layout; function entry, exit and calling.  */

/* Enumeration to give which calling sequence to use.  */
enum rs6000_abi {
  ABI_NONE,
  ABI_AIX,			/* IBM's AIX */
  ABI_AIX_NODESC,		/* AIX calling sequence minus function descriptors */
  ABI_V4,			/* System V.4/eabi */
  ABI_NT,			/* Windows/NT */
  ABI_SOLARIS			/* Solaris */
};

extern enum rs6000_abi rs6000_current_abi;	/* available for use by subtarget */

/* Default ABI to compile code for */
#ifndef DEFAULT_ABI
#define DEFAULT_ABI ABI_AIX
/* The prefix to add to user-visible assembler symbols. */
#define USER_LABEL_PREFIX "."
#endif

/* Structure used to define the rs6000 stack */
typedef struct rs6000_stack {
  int first_gp_reg_save;	/* first callee saved GP register used */
  int first_fp_reg_save;	/* first callee saved FP register used */
  int lr_save_p;		/* true if the link reg needs to be saved */
  int cr_save_p;		/* true if the CR reg needs to be saved */
  int toc_save_p;		/* true if the TOC needs to be saved */
  int push_p;			/* true if we need to allocate stack space */
  int calls_p;			/* true if the function makes any calls */
  int main_p;			/* true if this is main */
  int main_save_p;		/* true if this is main and we need to save args */
  int fpmem_p;			/* true if float/int conversion temp needed */
  enum rs6000_abi abi;		/* which ABI to use */
  int gp_save_offset;		/* offset to save GP regs from initial SP */
  int fp_save_offset;		/* offset to save FP regs from initial SP */
  int lr_save_offset;		/* offset to save LR from initial SP */
  int cr_save_offset;		/* offset to save CR from initial SP */
  int toc_save_offset;		/* offset to save the TOC pointer */
  int varargs_save_offset;	/* offset to save the varargs registers */
  int main_save_offset;		/* offset to save main's args */
  int fpmem_offset;		/* offset for float/int conversion temp */
  int reg_size;			/* register size (4 or 8) */
  int varargs_size;		/* size to hold V.4 args passed in regs */
  int vars_size;		/* variable save area size */
  int parm_size;		/* outgoing parameter size */
  int main_size;		/* size to hold saving main's args */
  int save_size;		/* save area size */
  int fixed_size;		/* fixed size of stack frame */
  int gp_size;			/* size of saved GP registers */
  int fp_size;			/* size of saved FP registers */
  int cr_size;			/* size to hold CR if not in save_size */
  int lr_size;			/* size to hold LR if not in save_size */
  int fpmem_size;		/* size to hold float/int conversion */
  int toc_size;			/* size to hold TOC if not in save_size */
  int total_size;		/* total bytes allocated for stack */
} rs6000_stack_t;

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

/* 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.

   On the RS/6000, we grow upwards, from the area after the outgoing
   arguments.  */
/* #define FRAME_GROWS_DOWNWARD */

/* Size of the outgoing register save area */
#define RS6000_REG_SAVE (TARGET_32BIT ? 32 : 64)

/* Size of the fixed area on the stack */
#define RS6000_SAVE_AREA (TARGET_32BIT ? 24 : 48)

/* MEM representing address to save the TOC register */
#define RS6000_SAVE_TOC gen_rtx_MEM (Pmode, \
				     plus_constant (stack_pointer_rtx, \
						    (TARGET_32BIT ? 20 : 40)))

/* Offset & size for fpmem stack locations used for converting between
   float and integral types.  */
extern int rs6000_fpmem_offset;
extern int rs6000_fpmem_size;

/* Size of the V.4 varargs area if needed */
#define RS6000_VARARGS_AREA 0

/* Whether a V.4 varargs area is needed */
extern int rs6000_sysv_varargs_p;

/* Align an address */
#define RS6000_ALIGN(n,a) (((n) + (a) - 1) & ~((a) - 1))

/* Initialize data used by insn expanders.  This is called from
   init_emit, once for each function, before code is generated. */
#define INIT_EXPANDERS rs6000_init_expanders ()

/* Size of V.4 varargs area in bytes */
#define RS6000_VARARGS_SIZE \
  ((GP_ARG_NUM_REG * (TARGET_32BIT ? 4 : 8)) + (FP_ARG_NUM_REG * 8) + 8)

/* 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.

   On the RS/6000, the frame pointer is the same as the stack pointer,
   except for dynamic allocations.  So we start after the fixed area and
   outgoing parameter area.  */

#define STARTING_FRAME_OFFSET						\
  (RS6000_ALIGN (current_function_outgoing_args_size, 8)		\
   + RS6000_VARARGS_AREA						\
   + RS6000_SAVE_AREA)

/* Offset from the stack pointer register to an item dynamically
   allocated on the stack, e.g., by `alloca'.

   The default value for this macro is `STACK_POINTER_OFFSET' plus the
   length of the outgoing arguments.  The default is correct for most
   machines.  See `function.c' for details.  */
#define STACK_DYNAMIC_OFFSET(FUNDECL)					\
  (RS6000_ALIGN (current_function_outgoing_args_size, 8)		\
   + (STACK_POINTER_OFFSET))

/* If we generate an insn to push BYTES bytes,
   this says how many the stack pointer really advances by.
   On RS/6000, don't define this because there are no push insns.  */
/*  #define PUSH_ROUNDING(BYTES) */

/* Offset of first parameter from the argument pointer register value.
   On the RS/6000, we define the argument pointer to the start of the fixed
   area.  */
#define FIRST_PARM_OFFSET(FNDECL) RS6000_SAVE_AREA

/* Define this if stack space is still allocated for a parameter passed
   in a register.  The value is the number of bytes allocated to this
   area.  */
#define REG_PARM_STACK_SPACE(FNDECL)	RS6000_REG_SAVE

/* Define this if the above stack space is to be considered part of the
   space allocated by the caller.  */
#define OUTGOING_REG_PARM_STACK_SPACE

/* This is the difference between the logical top of stack and the actual sp.

   For the RS/6000, sp points past the fixed area. */
#define STACK_POINTER_OFFSET RS6000_SAVE_AREA

/* Define this if the maximum size of all the outgoing args is to be
   accumulated and pushed during the prologue.  The amount can be
   found in the variable current_function_outgoing_args_size.  */
#define ACCUMULATE_OUTGOING_ARGS

/* Value is the number of bytes of arguments automatically
   popped when returning from a subroutine call.
   FUNDECL is the declaration node of the function (as a tree),
   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.  */

#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.

   On RS/6000 an integer value is in r3 and a floating-point value is in
   fp1, unless -msoft-float.  */

#define FUNCTION_VALUE(VALTYPE, FUNC)				\
  gen_rtx_REG ((INTEGRAL_TYPE_P (VALTYPE)			\
		&& TYPE_PRECISION (VALTYPE) < BITS_PER_WORD)	\
	       || POINTER_TYPE_P (VALTYPE)			\
	       ? word_mode : TYPE_MODE (VALTYPE),		\
	       TREE_CODE (VALTYPE) == REAL_TYPE && TARGET_HARD_FLOAT ? 33 : 3)

/* 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,			\
	       GET_MODE_CLASS (MODE) == MODE_FLOAT && TARGET_HARD_FLOAT ? 33 : 3)

/* The definition of this macro implies that there are cases where
   a scalar value cannot be returned in registers.