path: root/gcc/optabs.h

/* Definitions for code generation pass of GNU compiler.
   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
   2010, 2012  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_OPTABS_H
#define GCC_OPTABS_H

#include "insn-codes.h"
#include "insn-opinit.h"

typedef enum optab_tag optab;
typedef enum optab_tag convert_optab;
typedef enum optab_tag direct_optab;

struct optab_libcall_d
{
  char libcall_suffix;
  const char *libcall_basename;
  void (*libcall_gen) (optab, const char *name,
		       char suffix, enum machine_mode);
};

struct convert_optab_libcall_d
{
  const char *libcall_basename;
  void (*libcall_gen) (convert_optab, const char *name,
		       enum machine_mode, enum machine_mode);
};

/* Given an enum insn_code, access the function to construct
   the body of that kind of insn.  */
#define GEN_FCN(CODE) (insn_data[CODE].genfun)

/* Contains the optab used for each rtx code, and vice-versa.  */
extern const optab code_to_optab_[NUM_RTX_CODE];
extern const enum rtx_code optab_to_code_[NUM_OPTABS];

static inline optab
code_to_optab (enum rtx_code code)
{
  return code_to_optab_[code];
}

static inline enum rtx_code
optab_to_code (optab op)
{
  return optab_to_code_[op];
}

extern const struct convert_optab_libcall_d convlib_def[NUM_CONVLIB_OPTABS];
extern const struct optab_libcall_d normlib_def[NUM_NORMLIB_OPTABS];

/* Returns the active icode for the given (encoded) optab.  */
extern enum insn_code raw_optab_handler (unsigned);
extern bool swap_optab_enable (optab, enum machine_mode, bool);

/* Target-dependent globals.  */
struct target_optabs {
  /* Patterns that are used by optabs that are enabled for this target.  */
  bool pat_enable[NUM_OPTAB_PATTERNS];
};

extern struct target_optabs default_target_optabs;
#if SWITCHABLE_TARGET
extern struct target_optabs *this_target_optabs;
#else
#define this_target_optabs (&default_target_optabs)
#endif

/* Define functions given in optabs.c.  */

extern rtx expand_widen_pattern_expr (sepops ops, rtx op0, rtx op1, rtx wide_op,
                                      rtx target, int unsignedp);

extern rtx expand_ternary_op (enum machine_mode mode, optab ternary_optab,
			      rtx op0, rtx op1, rtx op2, rtx target,
			      int unsignedp);

/* Expand a binary operation given optab and rtx operands.  */
extern rtx expand_binop (enum machine_mode, optab, rtx, rtx, rtx, int,
			 enum optab_methods);

extern rtx simplify_expand_binop (enum machine_mode mode, optab binoptab,
				  rtx op0, rtx op1, rtx target, int unsignedp,
				  enum optab_methods methods);

extern bool force_expand_binop (enum machine_mode, optab, rtx, rtx, rtx, int,
				enum optab_methods);

/* Expand a binary operation with both signed and unsigned forms.  */
extern rtx sign_expand_binop (enum machine_mode, optab, optab, rtx, rtx,
			      rtx, int, enum optab_methods);

/* Generate code to perform an operation on one operand with two results.  */
extern int expand_twoval_unop (optab, rtx, rtx, rtx, int);

/* Generate code to perform an operation on two operands with two results.  */
extern int expand_twoval_binop (optab, rtx, rtx, rtx, rtx, int);

/* Generate code to perform an operation on two operands with two
   results, using a library function.  */
extern bool expand_twoval_binop_libfunc (optab, rtx, rtx, rtx, rtx,
					 enum rtx_code);

/* Expand a unary arithmetic operation given optab rtx operand.  */
extern rtx expand_unop (enum machine_mode, optab, rtx, rtx, int);

/* Expand the absolute value operation.  */
extern rtx expand_abs_nojump (enum machine_mode, rtx, rtx, int);
extern rtx expand_abs (enum machine_mode, rtx, rtx, int, int);

/* Expand the one's complement absolute value operation.  */
extern rtx expand_one_cmpl_abs_nojump (enum machine_mode, rtx, rtx);

/* Expand the copysign operation.  */
extern rtx expand_copysign (rtx, rtx, rtx);

/* Generate an instruction with a given INSN_CODE with an output and
   an input.  */
extern void emit_unop_insn (enum insn_code, rtx, rtx, enum rtx_code);
extern bool maybe_emit_unop_insn (enum insn_code, rtx, rtx, enum rtx_code);

/* Find a widening optab even if it doesn't widen as much as we want.  */
#define find_widening_optab_handler(A,B,C,D) \
  find_widening_optab_handler_and_mode (A, B, C, D, NULL)
extern enum insn_code find_widening_optab_handler_and_mode (optab,
							    enum machine_mode,
							    enum machine_mode,
							    int,
							    enum machine_mode *);

/* An extra flag to control optab_for_tree_code's behavior.  This is needed to
   distinguish between machines with a vector shift that takes a scalar for the
   shift amount vs. machines that take a vector for the shift amount.  */
enum optab_subtype
{
  optab_default,
  optab_scalar,
  optab_vector
};

/* Return the optab used for computing the given operation on the type given by
   the second argument.  The third argument distinguishes between the types of
   vector shifts and rotates */
extern optab optab_for_tree_code (enum tree_code, const_tree, enum optab_subtype);

/* The various uses that a comparison can have; used by can_compare_p:
   jumps, conditional moves, store flag operations.  */
enum can_compare_purpose
{
  ccp_jump,
  ccp_cmov,
  ccp_store_flag
};

/* Nonzero if a compare of mode MODE can be done straightforwardly
   (without splitting it into pieces).  */
extern int can_compare_p (enum rtx_code, enum machine_mode,
			  enum can_compare_purpose);

/* Return the INSN_CODE to use for an extend operation.  */
extern enum insn_code can_extend_p (enum machine_mode, enum machine_mode, int);

/* Generate the body of an insn to extend Y (with mode MFROM)
   into X (with mode MTO).  Do zero-extension if UNSIGNEDP is nonzero.  */
extern rtx gen_extend_insn (rtx, rtx, enum machine_mode,
			    enum machine_mode, int);

/* Call this to reset the function entry for one optab.  */
extern void set_optab_libfunc (optab, enum machine_mode, const char *);
extern void set_conv_libfunc (convert_optab, enum machine_mode,
			      enum machine_mode, const char *);

/* Call this to install all of the __sync libcalls up to size MAX.  */
extern void init_sync_libfuncs (int max);

/* Generate code for a FIXED_CONVERT_EXPR.  */
extern void expand_fixed_convert (rtx, rtx, int, int);

/* Generate code for a FLOAT_EXPR.  */
extern void expand_float (rtx, rtx, int);

/* Return the insn_code for a FLOAT_EXPR.  */
enum insn_code can_float_p (enum machine_mode, enum machine_mode, int);

/* Return true if there is an inline compare and swap pattern.  */
extern bool can_compare_and_swap_p (enum machine_mode, bool);

/* Return true if there is an inline atomic exchange pattern.  */
extern bool can_atomic_exchange_p (enum machine_mode, bool);

/* Generate code for a compare and swap.  */
extern bool expand_atomic_compare_and_swap (rtx *, rtx *, rtx, rtx, rtx, bool,
					    enum memmodel, enum memmodel);

/* Generate memory barriers.  */
extern void expand_mem_thread_fence (enum memmodel);
extern void expand_mem_signal_fence (enum memmodel);

/* Check whether an operation represented by the code CODE is a
   convert operation that is supported by the target platform in
   vector form */
bool supportable_convert_operation (enum tree_code, tree, tree, tree *, 
                                    enum tree_code *);

/* Generate code for a FIX_EXPR.  */
extern void expand_fix (rtx, rtx, int);

/* Generate code for float to integral conversion.  */
extern bool expand_sfix_optab (rtx, rtx, convert_optab);

/* Generate code for a widening multiply.  */
extern rtx expand_widening_mult (enum machine_mode, rtx, rtx, rtx, int, optab);

/* Return tree if target supports vector operations for COND_EXPR.  */
bool expand_vec_cond_expr_p (tree, tree);

/* Generate code for VEC_COND_EXPR.  */
extern rtx expand_vec_cond_expr (tree, tree, tree, tree, rtx);
/* Generate code for VEC_LSHIFT_EXPR and VEC_RSHIFT_EXPR.  */
extern rtx expand_vec_shift_expr (sepops, rtx);

/* Return tree if target supports vector operations for VEC_PERM_EXPR.  */
extern bool can_vec_perm_p (enum machine_mode, bool, const unsigned char *);

/* Generate code for VEC_PERM_EXPR.  */
extern rtx expand_vec_perm (enum machine_mode, rtx, rtx, rtx, rtx);

/* Return non-zero if target supports a given highpart multiplication.  */
extern int can_mult_highpart_p (enum machine_mode, bool);

/* Generate code for MULT_HIGHPART_EXPR.  */
extern rtx expand_mult_highpart (enum machine_mode, rtx, rtx, rtx, bool);

/* Return the insn used to implement mode MODE of OP, or CODE_FOR_nothing
   if the target does not have such an insn.  */

static inline enum insn_code
optab_handler (optab op, enum machine_mode mode)
{
  unsigned scode = (op << 16) | mode;
  gcc_assert (op > LAST_CONV_OPTAB);
  return raw_optab_handler (scode);
}

/* Return the insn used to perform conversion OP from mode FROM_MODE
   to mode TO_MODE; return CODE_FOR_nothing if the target does not have
   such an insn.  */

static inline enum insn_code
convert_optab_handler (convert_optab op, enum machine_mode to_mode,
		       enum machine_mode from_mode)
{
  unsigned scode = (op << 16) | (from_mode << 8) | to_mode;
  gcc_assert (op > unknown_optab && op <= LAST_CONV_OPTAB);
  return raw_optab_handler (scode);
}

/* Like optab_handler, but for widening_operations that have a
   TO_MODE and a FROM_MODE.  */

static inline enum insn_code
widening_optab_handler (optab op, enum machine_mode to_mode,
			enum machine_mode from_mode)
{
  unsigned scode = (op << 16) | to_mode;
  if (to_mode != from_mode && from_mode != VOIDmode)
    {
      /* ??? Why does find_widening_optab_handler_and_mode attempt to
	 widen things that can't be widened?  E.g. add_optab... */
      if (op > LAST_CONV_OPTAB)
	return CODE_FOR_nothing;
      scode |= from_mode << 8;
    }
  return raw_optab_handler (scode);
}

/* Return the insn used to implement mode MODE of OP, or CODE_FOR_nothing
   if the target does not have such an insn.  */

static inline enum insn_code
direct_optab_handler (direct_optab op, enum machine_mode mode)
{
  return optab_handler (op, mode);
}

/* Return true if UNOPTAB is for a trapping-on-overflow operation.  */

static inline bool
trapv_unoptab_p (optab unoptab)
{
  return (unoptab == negv_optab
	  || unoptab == absv_optab); 
}

/* Return true if BINOPTAB is for a trapping-on-overflow operation.  */

static inline bool
trapv_binoptab_p (optab binoptab)
{
  return (binoptab == addv_optab
	  || binoptab == subv_optab
	  || binoptab == smulv_optab);
}

extern rtx optab_libfunc (optab optab, enum machine_mode mode);
extern rtx convert_optab_libfunc (convert_optab optab, enum machine_mode mode1,
			          enum machine_mode mode2);

/* Describes an instruction that inserts or extracts a bitfield.  */
struct extraction_insn
{
  /* The code of the instruction.  */
  enum insn_code icode;

  /* The mode that the structure operand should have.  This is byte_mode
     when using the legacy insv, extv and extzv patterns to access memory.  */
  enum machine_mode struct_mode;

  /* The mode of the field to be inserted or extracted, and by extension
     the mode of the insertion or extraction itself.  */
  enum machine_mode field_mode;

  /* The mode of the field's bit position.  This is only important
     when the position is variable rather than constant.  */
  enum machine_mode pos_mode;
};

/* Enumerates the possible extraction_insn operations.  */
enum extraction_pattern { EP_insv, EP_extv, EP_extzv };

extern bool get_best_reg_extraction_insn (extraction_insn *,
					  enum extraction_pattern,
					  unsigned HOST_WIDE_INT,
					  enum machine_mode);

extern bool get_best_mem_extraction_insn (extraction_insn *,
					  enum extraction_pattern,
					  HOST_WIDE_INT, HOST_WIDE_INT,
					  enum machine_mode);

extern bool insn_operand_matches (enum insn_code icode, unsigned int opno,
				  rtx operand);

/* Describes the type of an expand_operand.  Each value is associated
   with a create_*_operand function; see the comments above those
   functions for details.  */
enum expand_operand_type {
  EXPAND_FIXED,
  EXPAND_OUTPUT,
  EXPAND_INPUT,
  EXPAND_CONVERT_TO,
  EXPAND_CONVERT_FROM,
  EXPAND_ADDRESS,
  EXPAND_INTEGER
};

/* Information about an operand for instruction expansion.  */
struct expand_operand {
  /* The type of operand.  */
  ENUM_BITFIELD (expand_operand_type) type : 8;

  /* True if any conversion should treat VALUE as being unsigned
     rather than signed.  Only meaningful for certain types.  */
  unsigned int unsigned_p : 1;

  /* Unused; available for future use.  */
  unsigned int unused : 7;

  /* The mode passed to the convert_*_operand function.  It has a
     type-dependent meaning.  */
  ENUM_BITFIELD (machine_mode) mode : 16;

  /* The value of the operand.  */
  rtx value;
};

/* Initialize OP with the given fields.  Initialise the other fields
   to their default values.  */

static inline void
create_expand_operand (struct expand_operand *op,
		       enum expand_operand_type type,
		       rtx value, enum machine_mode mode,
		       bool unsigned_p)
{
  op->type = type;
  op->unsigned_p = unsigned_p;
  op->unused = 0;
  op->mode = mode;
  op->value = value;
}

/* Make OP describe an operand that must use rtx X, even if X is volatile.  */

static inline void
create_fixed_operand (struct expand_operand *op, rtx x)
{
  create_expand_operand (op, EXPAND_FIXED, x, VOIDmode, false);
}

/* Make OP describe an output operand that must have mode MODE.
   X, if nonnull, is a suggestion for where the output should be stored.
   It is OK for VALUE to be inconsistent with MODE, although it will just
   be ignored in that case.  */

static inline void
create_output_operand (struct expand_operand *op, rtx x,
		       enum machine_mode mode)
{
  create_expand_operand (op, EXPAND_OUTPUT, x, mode, false);
}

/* Make OP describe an input operand that must have mode MODE and
   value VALUE; MODE cannot be VOIDmode.  The backend may request that
   VALUE be copied into a different kind of rtx before being passed
   as an operand.  */

static inline void
create_input_operand (struct expand_operand *op, rtx value,
		      enum machine_mode mode)
{
  create_expand_operand (op, EXPAND_INPUT, value, mode, false);
}

/* Like create_input_operand, except that VALUE must first be converted
   to mode MODE.  UNSIGNED_P says whether VALUE is unsigned.  */

static inline void
create_convert_operand_to (struct expand_operand *op, rtx value,
			   enum machine_mode mode, bool unsigned_p)
{
  create_expand_operand (op, EXPAND_CONVERT_TO, value, mode, unsigned_p);
}

/* Make OP describe an input operand that should have the same value
   as VALUE, after any mode conversion that the backend might request.
   If VALUE is a CONST_INT, it should be treated as having mode MODE.
   UNSIGNED_P says whether VALUE is unsigned.  */

static inline void
create_convert_operand_from (struct expand_operand *op, rtx value,
			     enum machine_mode mode, bool unsigned_p)
{
  create_expand_operand (op, EXPAND_CONVERT_FROM, value, mode, unsigned_p);
}

extern void create_convert_operand_from_type (struct expand_operand *op,
					      rtx value, tree type);

/* Make OP describe an input Pmode address operand.  VALUE is the value
   of the address, but it may need to be converted to Pmode first.  */

static inline void
create_address_operand (struct expand_operand *op, rtx value)
{
  create_expand_operand (op, EXPAND_ADDRESS, value, Pmode, false);
}

/* Make OP describe an input operand that has value INTVAL and that has
   no inherent mode.  This function should only be used for operands that
   are always expand-time constants.  The backend may request that INTVAL
   be copied into a different kind of rtx, but it must specify the mode
   of that rtx if so.  */

static inline void
create_integer_operand (struct expand_operand *op, HOST_WIDE_INT intval)
{
  create_expand_operand (op, EXPAND_INTEGER, GEN_INT (intval), VOIDmode, false);
}

extern bool valid_multiword_target_p (rtx);

extern bool maybe_legitimize_operands (enum insn_code icode,
				       unsigned int opno, unsigned int nops,
				       struct expand_operand *ops);
extern rtx maybe_gen_insn (enum insn_code icode, unsigned int nops,
			   struct expand_operand *ops);
extern bool maybe_expand_insn (enum insn_code icode, unsigned int nops,
			       struct expand_operand *ops);
extern bool maybe_expand_jump_insn (enum insn_code icode, unsigned int nops,
				    struct expand_operand *ops);
extern void expand_insn (enum insn_code icode, unsigned int nops,
			 struct expand_operand *ops);
extern void expand_jump_insn (enum insn_code icode, unsigned int nops,
			      struct expand_operand *ops);

extern rtx prepare_operand (enum insn_code, rtx, int, enum machine_mode,
			    enum machine_mode, int);

extern void gen_int_libfunc (optab, const char *, char, enum machine_mode);
extern void gen_fp_libfunc (optab, const char *, char, enum machine_mode);
extern void gen_fixed_libfunc (optab, const char *, char, enum machine_mode);
extern void gen_signed_fixed_libfunc (optab, const char *, char,
				      enum machine_mode);
extern void gen_unsigned_fixed_libfunc (optab, const char *, char,
					enum machine_mode);
extern void gen_int_fp_libfunc (optab, const char *, char, enum machine_mode);
extern void gen_intv_fp_libfunc (optab, const char *, char, enum machine_mode);
extern void gen_int_fp_fixed_libfunc (optab, const char *, char,
				      enum machine_mode);
extern void gen_int_fp_signed_fixed_libfunc (optab, const char *, char,
					     enum machine_mode);
extern void gen_int_fixed_libfunc (optab, const char *, char,
				   enum machine_mode);
extern void gen_int_signed_fixed_libfunc (optab, const char *, char,
					  enum machine_mode);
extern void gen_int_unsigned_fixed_libfunc (optab, const char *, char,
					    enum machine_mode);

extern void gen_interclass_conv_libfunc (convert_optab, const char *,
					 enum machine_mode, enum machine_mode);
extern void gen_int_to_fp_conv_libfunc (convert_optab, const char *,
					enum machine_mode, enum machine_mode);
extern void gen_ufloat_conv_libfunc (convert_optab, const char *,
				     enum machine_mode, enum machine_mode);
extern void gen_int_to_fp_nondecimal_conv_libfunc  (convert_optab,
						    const char *,
						    enum machine_mode,
						    enum machine_mode);
extern void gen_fp_to_int_conv_libfunc (convert_optab, const char *,
					enum machine_mode, enum machine_mode);
extern void gen_intraclass_conv_libfunc (convert_optab, const char *,
					 enum machine_mode, enum machine_mode);
extern void gen_trunc_conv_libfunc (convert_optab, const char *,
				    enum machine_mode, enum machine_mode);
extern void gen_extend_conv_libfunc (convert_optab, const char *,
				     enum machine_mode, enum machine_mode);
extern void gen_fract_conv_libfunc (convert_optab, const char *,
				    enum machine_mode, enum machine_mode);
extern void gen_fractuns_conv_libfunc (convert_optab, const char *,
				       enum machine_mode, enum machine_mode);
extern void gen_satfract_conv_libfunc (convert_optab, const char *,
				       enum machine_mode, enum machine_mode);
extern void gen_satfractuns_conv_libfunc (convert_optab, const char *,
					  enum machine_mode,
					  enum machine_mode);

#endif /* GCC_OPTABS_H */