gcc/config/avr/predicates.md

;; Insn predicate definitions for AVR 8-bit microcontrollers.
;; Copyright (C) 2006-2025 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/>.

;; Registers from r0 to r15.
(define_predicate "l_register_operand"
  (and (match_code "reg")
       (match_test "REGNO (op) <= 15")))

;; Registers from r16 to r31.
(define_predicate "d_register_operand"
  (and (match_code "reg")
       (match_test "REGNO (op) >= 16 && REGNO (op) <= 31")))

(define_predicate "scratch_or_dreg_operand"
  (ior (match_operand 0 "d_register_operand")
       (and (match_code ("scratch"))
            (match_operand 0 "scratch_operand"))))

(define_predicate "even_register_operand"
  (and (match_code "reg")
       (and (match_test "REGNO (op) <= 31")
            (match_test "(REGNO (op) & 1) == 0"))))

(define_predicate "odd_register_operand"
  (and (match_code "reg")
       (and (match_test "REGNO (op) <= 31")
            (match_test "(REGNO (op) & 1) != 0"))))

;; SP register.
(define_predicate "stack_register_operand"
  (and (match_code "reg")
       (match_test "REGNO (op) == REG_SP")))

;; Return true if OP is a valid address for lower half of I/O space.
(define_special_predicate "low_io_address_operand"
  (ior (and (match_code "const_int")
            (match_test "IN_RANGE (INTVAL (op) - avr_arch->sfr_offset,
                                   0, 0x1F)"))
       (and (match_code "symbol_ref")
            (match_test "SYMBOL_REF_FLAGS (op) & SYMBOL_FLAG_IO_LOW"))))

;; Return true if OP is a register_operand or low_io_operand.
(define_predicate "reg_or_low_io_operand"
  (ior (match_operand 0 "register_operand")
       (and (match_code "mem")
            ; Deliberately only allow QImode no matter what the mode of
            ; the operand is.  This effectively disallows and I/O that
            ; is not QImode for that operand.
            (match_test "GET_MODE (op) == QImode")
            (match_test "low_io_address_operand (XEXP (op, 0), Pmode)"))))

;; Return true if OP is a valid address for high half of I/O space.
(define_predicate "high_io_address_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op) - avr_arch->sfr_offset,
                              0x20, 0x3F)")))

;; Return true if OP is a valid address of I/O space.
(define_special_predicate "io_address_operand"
  (ior (and (match_code "const_int")
            (match_test "IN_RANGE (INTVAL (op) - avr_arch->sfr_offset,
                                   0, 0x3F)"))
       (and (match_code "symbol_ref")
            (match_test "SYMBOL_REF_FLAGS (op) & SYMBOL_FLAG_IO"))))

;; Return 1 if OP is a general operand not in flash memory
(define_predicate "nop_general_operand"
  (and (match_operand 0 "general_operand")
       (match_test "!avr_mem_flash_p (op)")))

;; Return 1 if OP is an "ordinary" general operand, i.e. a general
;; operand whose load is not handled by a libgcc call or ELPM.
(define_predicate "nox_general_operand"
  (and (match_operand 0 "general_operand")
       (not (match_test "avr_load_libgcc_p (op)"))
       (not (match_test "avr_mem_flashx_p (op)"))
       (not (match_test "avr_mem_memx_p (op)"))))

;; Return 1 if OP is the zero constant for MODE.
(define_predicate "const0_operand"
  (and (match_code "const_int,const_fixed,const_double")
       (match_test "op == CONST0_RTX (mode)")))

;; Return 1 if OP is the one constant integer for MODE.
(define_predicate "const1_operand"
  (and (match_code "const_int")
       (match_test "op == CONST1_RTX (mode)")))

;; Return 1 if OP is the constant integer 7 for MODE.
(define_predicate "const7_operand"
  (and (match_code "const_int")
       (match_test "INTVAL(op) == 7")))

;; Return 1 if OP is the constant integer 15 for MODE.
(define_predicate "const15_operand"
  (and (match_code "const_int")
       (match_test "INTVAL(op) == 15")))

;; Return 1 if OP is the constant integer 23 for MODE.
(define_predicate "const23_operand"
  (and (match_code "const_int")
       (match_test "INTVAL(op) == 23")))

;; Return 1 if OP is the constant integer 31 for MODE.
(define_predicate "const31_operand"
  (and (match_code "const_int")
       (match_test "INTVAL(op) == 31")))


;; Return 1 if OP is constant integer 0..7 for MODE.
(define_predicate "const_0_to_7_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, 7)")))

;; Return 1 if OP is constant integer 0..15 for MODE.
(define_predicate "const_0_to_15_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, 15)")))

;; Return 1 if OP is constant integer 0..23 for MODE.
(define_predicate "const_0_to_23_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, 23)")))

;; Return 1 if OP is constant integer 0..31 for MODE.
(define_predicate "const_0_to_31_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, 31)")))

;; Return 1 if OP is constant integer 2..7 for MODE.
(define_predicate "const_2_to_7_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 2, 7)")))

;; Return true if OP is constant integer 1..3 for MODE.
(define_predicate "const_1_to_3_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 1, 3)")))

;; Return 1 if OP is constant integer 1..6 for MODE.
(define_predicate "const_1_to_6_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 1, 6)")))

;; Return 1 if OP is constant integer 2..6 for MODE.
(define_predicate "const_2_to_6_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 2, 6)")))

;; Return 1 if OP is constant integer -255..-1.
(define_predicate "const_m255_to_m1_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -255, -1)")))

;; Return true if OP is a CONST_INT in { -2, -1, 1, 2 }.
(define_predicate "abs1_abs2_operand"
  (and (match_code "const_int")
       (match_test "INTVAL (op) != 0")
       (match_test "IN_RANGE (INTVAL (op), -2, 2)")))

;; Returns true if OP is either the constant zero or a register.
(define_predicate "reg_or_0_operand"
  (ior (match_operand 0 "register_operand")
       (match_operand 0 "const0_operand")))

;; Returns true if OP is either the constant zero or an upper register.
(define_predicate "dreg_or_0_operand"
  (ior (match_operand 0 "d_register_operand")
       (match_operand 0 "const0_operand")))

;; Returns 1 if OP is a SYMBOL_REF.
(define_predicate "symbol_ref_operand"
  (match_code "symbol_ref"))

;; Returns true when OP is a SYMBOL_REF, CONST or CONST_INT that is
;; a multiple of 256, i.e. lo8(OP) = 0.
(define_predicate "const_0mod256_operand"
  (ior (and (match_code "symbol_ref")
            (match_test "SYMBOL_REF_DECL (op)
                         && DECL_P (SYMBOL_REF_DECL (op))
                         && DECL_ALIGN (SYMBOL_REF_DECL (op)) >= 8 * 256"))
       (and (match_code "const")
            (match_test "GET_CODE (XEXP (op, 0)) == PLUS")
            (match_test "const_0mod256_operand (XEXP (XEXP (op, 0), 0), HImode)")
            (match_test "const_0mod256_operand (XEXP (XEXP (op, 0), 1), HImode)"))
       (and (match_code "const_int")
            (match_test "INTVAL (op) % 256 == 0"))))

;; Return true if OP is a text segment reference.
;; This is needed for program memory address expressions.
(define_predicate "text_segment_operand"
  (match_code "code_label,label_ref,symbol_ref,plus,const")
{
  switch (GET_CODE (op))
    {
    case CODE_LABEL:
      return true;
    case LABEL_REF :
      return true;
    case SYMBOL_REF :
      return SYMBOL_REF_FUNCTION_P (op);
    case PLUS :
      // Assume canonical format of symbol + constant.
      // Fall through.
    case CONST :
      return text_segment_operand (XEXP (op, 0), VOIDmode);
    default :
      return false;
    }
})

;; Return true if OP is a constant that contains only one 1 in its
;; binary representation.
(define_predicate "single_one_operand"
  (and (match_code "const_int")
       (match_test "exact_log2(INTVAL (op) & GET_MODE_MASK (mode)) >= 0")))

;; Return true if OP is a constant that contains only one 0 in its
;; binary representation.
(define_predicate "single_zero_operand"
  (and (match_code "const_int")
       (match_test "exact_log2(~INTVAL (op) & GET_MODE_MASK (mode)) >= 0")))

;;
(define_predicate "avr_sp_immediate_operand"
  (and (match_code "const_int")
       (match_test "satisfies_constraint_Csp (op)")))

;; True for EQ & NE
(define_predicate "eqne_operator"
  (match_code "eq,ne"))

;; True for GE & LT
(define_predicate "gelt_operator"
  (match_code "ge,lt"))

;; True for GT, GTU, LE & LEU
(define_predicate "difficult_comparison_operator"
  (match_code "gt,gtu,le,leu"))

;; False for GT, GTU, LE & LEU
(define_predicate "simple_comparison_operator"
  (and (match_operand 0 "comparison_operator")
       (not (match_code "gt,gtu,le,leu"))))

;; True for EQ, NE, GE, LT, GT, LE
(define_predicate "signed_comparison_operator"
  (match_code "eq,ne,ge,lt,gt,le"))

;; True for SIGN_EXTEND, ZERO_EXTEND.
(define_predicate "extend_operator"
  (match_code "sign_extend,zero_extend"))

;; True for 8-bit operations that set SREG.N and SREG.Z in a
;; usable way:
;; * OP0 is a QImode register, and
;; * OP1 is a QImode register or CONST_INT, and
;;
;; the allowed operations is one of:
;;
;; * SHIFTs with a const_int offset in { 1, 2, 3 }.
;; * MINUS and XOR with a register operand
;; * IOR and AND with a register operand, or d-reg + const_int
;; * PLUS with a register operand, or d-reg + const_int,
;;   or a const_int in { -2, -1, 1, 2 }.  */
(define_predicate "op8_ZN_operator"
  (and (match_code "plus,minus,ashift,ashiftrt,lshiftrt,and,ior,xor")
       (match_test "avr_op8_ZN_operator (op)")))

;; Return true if OP is a valid call operand.
(define_predicate "call_insn_operand"
  (and (match_code "mem")
       (ior (match_test "register_operand (XEXP (op, 0), mode)")
            (match_test "CONSTANT_ADDRESS_P (XEXP (op, 0))"))))

;; For some insns we must ensure that no hard register is inserted
;; into their operands because the insns are split and the split
;; involves hard registers.  An example are divmod insn that are
;; split to insns that represent implicit library calls.

;; True for register that is pseudo register.
(define_predicate "pseudo_register_operand"
  (and (match_operand 0 "register_operand")
       (not (and (match_code "reg")
                 (match_test "HARD_REGISTER_P (op)")))))

;; True for operand that is pseudo register or CONST_INT.
(define_predicate "pseudo_register_or_const_int_operand"
  (ior (match_operand 0 "const_int_operand")
       (match_operand 0 "pseudo_register_operand")))

;; We keep combiner from inserting hard registers into the input of sign- and
;; zero-extends.  A hard register in the input operand is not wanted because
;; 32-bit multiply patterns clobber some hard registers and extends with a
;; hard register that overlaps these clobbers won't combine to a widening
;; multiplication.  There is no need for combine to propagate or insert
;; hard registers, register allocation can do it just as well.

;; True for operand that is pseudo register at combine time.
(define_predicate "combine_pseudo_register_operand"
  (ior (match_operand 0 "pseudo_register_operand")
       (and (match_operand 0 "register_operand")
            (match_test "reload_completed || reload_in_progress"))))

;; Return true if OP is a constant integer that is either
;; 8 or 16 or 24.
(define_predicate "const_8_16_24_operand"
  (and (match_code "const_int")
       (match_test "INTVAL(op) == 8 || INTVAL(op) == 16 || INTVAL(op) == 24")))

;; Unsigned CONST_INT that fits in 8 bits, i.e. 0..255.
(define_predicate "u8_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, 255)")))

;; Signed CONST_INT that fits in 8 bits, i.e. -128..127.
(define_predicate "s8_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -128, 127)")))

;; One-extended CONST_INT that fits in 8 bits, i.e. -256..-1.
(define_predicate "o8_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -256, -1)")))

;; Signed CONST_INT that fits in 9 bits, i.e. -256..255.
(define_predicate "s9_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -256, 255)")))

(define_predicate "register_or_s9_operand"
  (ior (match_operand 0 "register_operand")
       (match_operand 0 "s9_operand")))

;; Unsigned CONST_INT that fits in 16 bits, i.e. 0..65536.
(define_predicate "u16_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), 0, (1<<16)-1)")))

;; Signed CONST_INT that fits in 16 bits, i.e. -32768..32767.
(define_predicate "s16_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -(1<<15), (1<<15)-1)")))

;; One-extended CONST_INT that fits in 16 bits, i.e. -65536..-1.
(define_predicate "o16_operand"
  (and (match_code "const_int")
       (match_test "IN_RANGE (INTVAL (op), -(1<<16), -1)")))

;; Const int, fixed, or double operand
(define_predicate "const_operand"
  (ior (match_code "const_fixed")
       (match_code "const_double")
       (match_operand 0 "const_int_operand")))

;; Const int, const fixed, or const double operand
(define_predicate "nonmemory_or_const_operand"
  (ior (match_code "const_fixed")
       (match_code "const_double")
       (match_operand 0 "nonmemory_operand")))

;; Immediate, const fixed, or const double operand
(define_predicate "const_or_immediate_operand"
  (ior (match_code "const_fixed")
       (match_code "const_double")
       (match_operand 0 "immediate_operand")))

(define_predicate "set_some_operation"
  (and (match_code "parallel")
       (match_test "avr_set_some_operation (op)")))