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/*  This file is part of the program psim.

    Copyright (C) 1994-1996, Andrew Cagney <cagney@highland.com.au>

    Copyright (C) 1997, Free Software Foundation, Inc.

    This program 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 2 of the License, or

    (at your option) any later version.

    This program 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 this program; if not, write to the Free Software

    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

    */

#ifndef _SIM_ALU_H_

#define _SIM_ALU_H_

#include "symcat.h"

/* INTEGER ALU MODULE:

   This module provides an implementation of 2's complement arithmetic

   including the recording of carry and overflow status bits.

   EXAMPLE:

   Code using this module includes it into sim-main.h and then, as a

   convention, defines macro's ALU*_END that records the result of any

   aritmetic performed.  Ex:

        #include "sim-alu.h"

        #define ALU32_END(RES) \

        (RES) = ALU32_OVERFLOW_RESULT; \

        carry = ALU32_HAD_CARRY_BORROW; \

        overflow = ALU32_HAD_OVERFLOW

   The macro's are then used vis:

        {

          ALU32_BEGIN (GPR[i]);

          ALU32_ADDC (GPR[j]);

          ALU32_END (GPR[k]);

        }

   NOTES:

   Macros exist for efficiently computing 8, 16, 32 and 64 bit

   arithmetic - ALU8_*, ALU16_*, ....  In addition, according to

   TARGET_WORD_BITSIZE a set of short-hand macros are defined - ALU_*

   Initialization:

        ALU*_BEGIN(ACC): Declare initialize the ALU accumulator with ACC.

   Results:

        The calculation of the final result may be computed a number

        of different ways.  Three different overflow macro's are

        defined, the most efficient one to use depends on which other

        outputs from the alu are being used.

        ALU*_RESULT: Generic ALU result output.

        ALU*_HAD_OVERFLOW: Returns a nonzero value if signed overflow

        occured.

        ALU*_OVERFLOW_RESULT: If the macro ALU*_HAD_OVERFLOW is being

        used this is the most efficient result available.  Ex:

                #define ALU16_END(RES) \

                if (ALU16_HAD_OVERFLOW) \

                  sim_engine_halt (...); \

                (RES) = ALU16_OVERFLOW_RESULT

        ALU*_HAD_CARRY_BORROW: Returns a nonzero value if unsigned

        overflow or underflow (also refered to as carry and borrow)

        occured.

        ALU*_CARRY_BORROW_RESULT: If the macro ALU*_HAD_CARRY_BORROW is being

        used this is the most efficient result available.  Ex:

                #define ALU64_END(RES) \

                State.carry = ALU64_HAD_CARRY_BORROW; \

                (RES) = ALU64_CARRY_BORROW_RESULT

   Addition:

        ALU*_ADD(VAL): Add VAL to the ALU accumulator.  Record any

        overflow as well as the final result.

        ALU*_ADDC(VAL): Add VAL to the ALU accumulator.  Record any

        carry-out or overflow as well as the final result.

        ALU*_ADDC_C(VAL,CI): Add VAL and CI (carry-in).  Record any

        carry-out or overflow as well as the final result.

   Subtraction:

        ALU*_SUB(VAL): Subtract VAL from the ALU accumulator.  Record

        any underflow as well as the final result.

        ALU*_SUBC(VAL): Subtract VAL from the ALU accumulator using

        negated addition.  Record any underflow or carry-out as well

        as the final result.

        ALU*_SUBB(VAL): Subtract VAL from the ALU accumulator using

        direct subtraction (ACC+~VAL+1).  Record any underflow or

        borrow-out as well as the final result.

        ALU*_SUBC_X(VAL,CI): Subtract VAL and CI (carry-in) from the

        ALU accumulator using extended negated addition (ACC+~VAL+CI).

        Record any underflow or carry-out as well as the final result.

        ALU*_SUBB_B(VAL,BI): Subtract VAL and BI (borrow-in) from the

        ALU accumulator using direct subtraction.  Record any

        underflow or borrow-out as well as the final result.

 */

/* Twos complement aritmetic - addition/subtraction - carry/borrow

   (or you thought you knew the answer to 0-0)

   Notation and Properties:

   Xn denotes the value X stored in N bits.

   MSBn (X): The most significant (sign) bit of X treated as an N bit

   value.

   SEXTn (X): The infinite sign extension of X treated as an N bit

   value.

   MAXn, MINn: The upper and lower bound of a signed, two's

   complement N bit value.

   UMAXn: The upper bound of an unsigned N bit value (the lower

   bound is always zero).

   Un: UMAXn + 1.  Unsigned arrithmetic is computed `modulo (Un)'.

   X[p]: Is bit P of X.  X[0] denotes the least signifant bit.

   ~X[p]: Is the inversion of bit X[p]. Also equal to 1-X[p],

   (1+X[p])mod(2).

   Addition - Overflow - Introduction:

   Overflow/Overflow indicates an error in computation of signed

   arrithmetic.  i.e. given X,Y in [MINn..MAXn]; overflow

   indicates that the result X+Y > MAXn or X+Y < MIN_INTx.

   Hardware traditionally implements overflow by computing the XOR of

   carry-in/carry-out of the most significant bit of the ALU. Here

   other methods need to be found.

   Addition - Overflow - method 1:

   Overflow occures when the sign (most significant bit) of the two N

   bit operands is identical but different to the sign of the result:

                Rn = (Xn + Yn)

                V = MSBn (~(Xn ^ Yn) & (Rn ^ Xn))

   Addition - Overflow - method 2:

   The two N bit operands are sign extended to M>N bits and then

   added.  Overflow occures when SIGN_BIT<n> and SIGN_BIT<m> do not

   match.

                Rm = (SEXTn (Xn) + SEXTn (Yn))

                V = MSBn ((Rm >> (M - N)) ^ Rm)

   Addition - Overflow - method 3:

   The two N bit operands are sign extended to M>N bits and then

   added.  Overflow occures when the result is outside of the sign

   extended range [MINn .. MAXn].

   Addition - Overflow - method 4:

   Given the Result and Carry-out bits, the oVerflow from the addition

   of X, Y and carry-In can be computed using the equation:

                Rn = (Xn + Yn)

                V = (MSBn ((Xn ^ Yn) ^ Rn)) ^ C)

   As shown in the table below:

         I  X  Y  R  C | V | X^Y  ^R  ^C

        ---------------+---+-------------

         1  0  0  1  0 | 1 |  0    1   1

         1  0  1  0  1 | 0 |  1    1   0

         1  1  0  0  1 | 0 |  1    1   0

         1  1  1  1  1 | 0 |  0    1   0

   Addition - Carry - Introduction:

   Carry (poorly named) indicates that an overflow occured for

   unsigned N bit addition.  i.e. given X, Y in [0..UMAXn] then

   carry indicates X+Y > UMAXn or X+Y >= Un.

   The following table lists the output for all given inputs into a

   full-adder.

         I  X  Y  R | C

        ------------+---

         1  0  0  1 | 0

         1  0  1  0 | 1

         1  1  0  0 | 1

         1  1  1  1 | 1

   (carry-In, X, Y, Result, Carry-out):

   Addition - Carry - method 1:

   Looking at the terms X, Y and R we want an equation for C.

       XY\R  0  1

          +-------

       00 |  0  0

       01 |  1  0

       11 |  1  1

       10 |  1  0

   This giving us the sum-of-prod equation:

                MSBn ((Xn & Yn) | (Xn & ~Rn) | (Yn & ~Rn))

   Verifying:

         I  X  Y  R | C | X&Y  X&~R Y&~R

        ------------+---+---------------

         1  0  0  1 | 0 |  0    0    0

         1  0  1  0 | 1 |  0    0    1

         1  1  0  0 | 1 |  0    1    0

         1  1  1  1 | 1 |  1    0    0

   Addition - Carry - method 2:

   Given two signed N bit numbers, a carry can be detected by treating

   the numbers as N bit unsigned and adding them using M>N unsigned

   arrithmetic.  Carry is indicated by bit (1 << N) being set (result

   >= 2**N).

   Addition - Carry - method 3:

   Given the oVerflow bit.  The carry can be computed from:

                (~R&V) | (R&V)

   Addition - Carry - method 4:

   Given two signed numbers.  Treating them as unsigned we have:

        ==>     X + Y < 2 Un

   Consider Y when carry occures:

                X + Y >= Un, Y < Un

        ==>     (Un - X) <= Y < Un               # re-arange

        ==>     Un <= X + Y < Un + X < 2 Un      # add Xn

        ==>     0 <= (X + Y) mod Un < X mod Un

   or when carry as occured:

               (X + Y) mod Un < X mod Un

   Consider Y when carry does not occure:

                X + Y < Un

        have    X < Un, Y >= 0

        ==>     X <= X + Y < Un

        ==>     X mod Un <= (X + Y) mod Un

   or when carry has not occured:

                ! ( (X + Y) mod Un < X mod Un)

   hence we get carry by computing in N bit unsigned arrithmetic.

                carry <- (Xn + Yn) < Xn

   Subtraction - Introduction

   There are two different ways of computing the signed two's

   complement difference of two numbers.  The first is based on

   negative addition, the second on direct subtraction.

   Subtraction - Carry - Introduction - Negated Addition

   The equation X - Y can be computed using:

                X + (-Y)

        ==>     X + ~Y + 1              # -Y = ~Y + 1

   In addition to the result, the equation produces Carry-out.  For

   succeeding extended prrcision calculations, the more general

   equation can be used:

                C[p]:R[p]  =  X[p] + ~Y[p] + C[p-1]

        where   C[0]:R[0]  =  X[0] + ~Y[0] + 1

   Subtraction - Borrow - Introduction - Direct Subtraction

   The alternative to negative addition is direct subtraction where

   `X-Y is computed directly.  In addition to the result of the

   calculation, a Borrow bit is produced.  In general terms:

                B[p]:R[p]  =  X[p] - Y[p] - B[p-1]

        where   B[0]:R[0]  =  X[0] - Y[0]

   The Borrow bit is the complement of the Carry bit produced by

   Negated Addition above.  A dodgy proof follows:

        Case 0:

                C[0]:R[0] = X[0] + ~Y[0] + 1

        ==>     C[0]:R[0] = X[0] + 1 - Y[0] + 1 # ~Y[0] = (1 - Y[0])?

        ==>     C[0]:R[0] = 2 + X[0] - Y[0]

        ==>     C[0]:R[0] = 2 + B[0]:R[0]

        ==>     C[0]:R[0] = (1 + B[0]):R[0]

        ==>     C[0] = ~B[0]                    # (1 + B[0]) mod 2 = ~B[0]?

        Case P:

                C[p]:R[p] = X[p] + ~Y[p] + C[p-1]

        ==>     C[p]:R[p] = X[p] + 1 - Y[0] + 1 - B[p-1]

        ==>     C[p]:R[p] = 2 + X[p] - Y[0] - B[p-1]

        ==>     C[p]:R[p] = 2 + B[p]:R[p]

        ==>     C[p]:R[p] = (1 + B[p]):R[p]

        ==>     C[p] = ~B[p]

   The table below lists all possible inputs/outputs for a

   full-subtractor:

        X  Y  I  |  R  B

        1  0  0  |  1  0

        1  0  1  |  0  0

        1  1  0  |  0  0

        1  1  1  |  1  1

   Subtraction - Method 1

   Treating Xn and Yn as unsigned values then a borrow (unsigned

   underflow) occures when:

                B = Xn < Yn

        ==>     C = Xn >= Yn

 */

/* 8 bit target expressions:

   Since the host's natural bitsize > 8 bits, carry method 2 and

   overflow method 2 are used. */

#define ALU8_BEGIN(VAL) \

unsigned alu8_cr = (unsigned8) (VAL); \

signed alu8_vr = (signed8) (alu8_cr)

#define ALU8_SET(VAL) \

alu8_cr = (unsigned8) (VAL); \

alu8_vr = (signed8) (alu8_cr)

#define ALU8_SET_CARRY_BORROW(CARRY)                                    \

do {                                                                    \

  if (CARRY)                                                            \

    alu8_cr |= ((signed)-1) << 8;                                       \

  else                                                                  \

    alu8_cr &= 0xff;                                                    \

} while (0)

#define ALU8_HAD_CARRY_BORROW (alu8_cr & LSBIT32(8))

#define ALU8_HAD_OVERFLOW (((alu8_vr >> 8) ^ alu8_vr) & LSBIT32 (8-1))

#define ALU8_RESULT ((unsigned8) alu8_cr)

#define ALU8_CARRY_BORROW_RESULT ((unsigned8) alu8_cr)

#define ALU8_OVERFLOW_RESULT ((unsigned8) alu8_vr)

/* #define ALU8_END ????? - target dependant */

/* 16 bit target expressions:

   Since the host's natural bitsize > 16 bits, carry method 2 and

   overflow method 2 are used. */

#define ALU16_BEGIN(VAL) \

signed alu16_cr = (unsigned16) (VAL); \

unsigned alu16_vr = (signed16) (alu16_cr)

#define ALU16_SET(VAL) \

alu16_cr = (unsigned16) (VAL); \

alu16_vr = (signed16) (alu16_cr)

#define ALU16_SET_CARRY_BORROW(CARRY)                                   \

do {                                                                    \

  if (CARRY)                                                            \

    alu16_cr |= ((signed)-1) << 16;                                     \

  else                                                                  \

    alu16_cr &= 0xffff;                                                 \

} while (0)

#define ALU16_HAD_CARRY_BORROW (alu16_cr & LSBIT32(16))

#define ALU16_HAD_OVERFLOW (((alu16_vr >> 16) ^ alu16_vr) & LSBIT32 (16-1))

#define ALU16_RESULT ((unsigned16) alu16_cr)

#define ALU16_CARRY_BORROW_RESULT ((unsigned16) alu16_cr)

#define ALU16_OVERFLOW_RESULT ((unsigned16) alu16_vr)

/* #define ALU16_END ????? - target dependant */

/* 32 bit target expressions:

   Since most hosts do not support 64 (> 32) bit arrithmetic, carry

   method 4 and overflow method 4 are used. */

#define ALU32_BEGIN(VAL) \

unsigned32 alu32_r = (VAL); \

int alu32_c = 0; \

int alu32_v = 0

#define ALU32_SET(VAL) \

alu32_r = (VAL); \

alu32_c = 0; \

alu32_v = 0

#define ALU32_SET_CARRY_BORROW(CARRY) alu32_c = (CARRY)

#define ALU32_HAD_CARRY_BORROW (alu32_c)

#define ALU32_HAD_OVERFLOW (alu32_v)

#define ALU32_RESULT (alu32_r)

#define ALU32_CARRY_BORROW_RESULT (alu32_r)

#define ALU32_OVERFLOW_RESULT (alu32_r)

/* 64 bit target expressions:

   Even though the host typically doesn't support native 64 bit

   arrithmetic, it is still used. */

#define ALU64_BEGIN(VAL) \

unsigned64 alu64_r = (VAL); \

int alu64_c = 0; \

int alu64_v = 0

#define ALU64_SET(VAL) \

alu64_r = (VAL); \

alu64_c = 0; \

alu64_v = 0

#define ALU64_SET_CARRY_BORROW(CARRY) alu64_c = (CARRY)

#define ALU64_HAD_CARRY_BORROW (alu64_c)

#define ALU64_HAD_OVERFLOW (alu64_v)

#define ALU64_RESULT (alu64_r)

#define ALU64_CARRY_BORROW_RESULT (alu64_r)

#define ALU64_OVERFLOW_RESULT (alu64_r)

/* Generic versions of above macros */

#define ALU_BEGIN           XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_BEGIN)

#define ALU_SET             XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SET)

#define ALU_SET_CARRY       XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SET_CARRY)

#define ALU_HAD_OVERFLOW    XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_HAD_OVERFLOW)

#define ALU_HAD_CARRY       XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_HAD_CARRY)

#define ALU_RESULT          XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_RESULT)

#define ALU_OVERFLOW_RESULT XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_OVERFLOW_RESULT)

#define ALU_CARRY_RESULT    XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_CARRY_RESULT)

/* Basic operation - add (overflowing) */

#define ALU8_ADD(VAL)                                                   \

do {                                                                    \

  unsigned8 alu8add_val = (VAL);                                        \

  ALU8_ADDC (alu8add_val);                                              \

} while (0)

#define ALU16_ADD(VAL)                                                  \

do {                                                                    \

  unsigned16 alu16add_val = (VAL);                                      \

  ALU16_ADDC (alu8add_val);                                             \

} while (0)

#define ALU32_ADD(VAL)                                                  \

do {                                                                    \

  unsigned32 alu32add_val = (VAL);                                      \

  ALU32_ADDC (alu32add_val);                                            \

} while (0)

#define ALU64_ADD(VAL)                                                  \

do {                                                                    \

  unsigned64 alu64add_val = (unsigned64) (VAL);                         \

  ALU64_ADDC (alu64add_val);                                            \

} while (0)

#define ALU_ADD XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_ADD)

/* Basic operation - add carrying (and overflowing) */

#define ALU8_ADDC(VAL)                                                  \

do {                                                                    \

  unsigned8 alu8addc_val = (VAL);                                       \

  alu8_cr += (unsigned8)(alu8addc_val);                                 \

  alu8_vr += (signed8)(alu8addc_val);                                   \

} while (0)

#define ALU16_ADDC(VAL)                                                 \

do {                                                                    \

  unsigned16 alu16addc_val = (VAL);                                     \

  alu16_cr += (unsigned16)(alu16addc_val);                              \

  alu16_vr += (signed16)(alu16addc_val);                                \

} while (0)

#define ALU32_ADDC(VAL)                                                 \

do {                                                                    \

  unsigned32 alu32addc_val = (VAL);                                     \

  unsigned32 alu32addc_sign = alu32addc_val ^ alu32_r;                  \

  alu32_r += (alu32addc_val);                                           \

  alu32_c = (alu32_r < alu32addc_val);                                  \

  alu32_v = ((alu32addc_sign ^ - (unsigned32)alu32_c) ^ alu32_r) >> 31; \

} while (0)

#define ALU64_ADDC(VAL)                                                 \

do {                                                                    \

  unsigned64 alu64addc_val = (unsigned64) (VAL);                        \

  unsigned64 alu64addc_sign = alu64addc_val ^ alu64_r;                  \

  alu64_r += (alu64addc_val);                                           \

  alu64_c = (alu64_r < alu64addc_val);                                  \

  alu64_v = ((alu64addc_sign ^ - (unsigned64)alu64_c) ^ alu64_r) >> 63; \

} while (0)

#define ALU_ADDC XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_ADDC)

/* Compound operation - add carrying (and overflowing) with carry-in */

#define ALU8_ADDC_C(VAL,C)                                              \

do {                                                                    \

  unsigned8 alu8addcc_val = (VAL);                                      \

  unsigned8 alu8addcc_c = (C);                                          \

  alu8_cr += (unsigned)(unsigned8)alu8addcc_val + alu8addcc_c;          \

  alu8_vr += (signed)(signed8)(alu8addcc_val) + alu8addcc_c;            \

} while (0)

#define ALU16_ADDC_C(VAL,C)                                             \

do {                                                                    \

  unsigned16 alu16addcc_val = (VAL);                                    \

  unsigned16 alu16addcc_c = (C);                                        \

  alu16_cr += (unsigned)(unsigned16)alu16addcc_val + alu16addcc_c;      \

  alu16_vr += (signed)(signed16)(alu16addcc_val) + alu16addcc_c;        \

} while (0)

#define ALU32_ADDC_C(VAL,C)                                             \

do {                                                                    \

  unsigned32 alu32addcc_val = (VAL);                                    \

  unsigned32 alu32addcc_c = (C);                                        \

  unsigned32 alu32addcc_sign = (alu32addcc_val ^ alu32_r);              \

  alu32_r += (alu32addcc_val + alu32addcc_c);                           \

  alu32_c = ((alu32_r < alu32addcc_val)                                 \

             || (alu32addcc_c && alu32_r == alu32addcc_val));           \

  alu32_v = ((alu32addcc_sign ^ - (unsigned32)alu32_c) ^ alu32_r) >> 31;\

} while (0)

#define ALU64_ADDC_C(VAL,C)                                             \

do {                                                                    \

  unsigned64 alu64addcc_val = (VAL);                                    \

  unsigned64 alu64addcc_c = (C);                                        \

  unsigned64 alu64addcc_sign = (alu64addcc_val ^ alu64_r);              \

  alu64_r += (alu64addcc_val + alu64addcc_c);                           \

  alu64_c = ((alu64_r < alu64addcc_val)                                 \

             || (alu64addcc_c && alu64_r == alu64addcc_val));           \

  alu64_v = ((alu64addcc_sign ^ - (unsigned64)alu64_c) ^ alu64_r) >> 63;\

} while (0)

#define ALU_ADDC_C XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_ADDC_C)

/* Basic operation - subtract (overflowing) */

#define ALU8_SUB(VAL)                                                   \

do {                                                                    \

  unsigned8 alu8sub_val = (VAL);                                        \

  ALU8_ADDC_C (~alu8sub_val, 1);                                        \

} while (0)

#define ALU16_SUB(VAL)                                                  \

do {                                                                    \

  unsigned16 alu16sub_val = (VAL);                                      \

  ALU16_ADDC_C (~alu16sub_val, 1);                                      \

} while (0)

#define ALU32_SUB(VAL)                                                  \

do {                                                                    \

  unsigned32 alu32sub_val = (VAL);                                      \

  ALU32_ADDC_C (~alu32sub_val, 1);                                      \

} while (0)

#define ALU64_SUB(VAL)                                                  \

do {                                                                    \

  unsigned64 alu64sub_val = (VAL);                                      \

  ALU64_ADDC_C (~alu64sub_val, 1);                                      \

} while (0)

#define ALU_SUB XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SUB)

/* Basic operation - subtract carrying (and overflowing) */

#define ALU8_SUBC(VAL)                                                  \

do {                                                                    \

  unsigned8 alu8subc_val = (VAL);                                       \

  ALU8_ADDC_C (~alu8subc_val, 1);                                       \

} while (0)

#define ALU16_SUBC(VAL)                                                 \

do {                                                                    \

  unsigned16 alu16subc_val = (VAL);                                     \

  ALU16_ADDC_C (~alu16subc_val, 1);                                     \

} while (0)

#define ALU32_SUBC(VAL)                                                 \

do {                                                                    \

  unsigned32 alu32subc_val = (VAL);                                     \

  ALU32_ADDC_C (~alu32subc_val, 1);                                     \

} while (0)

#define ALU64_SUBC(VAL)                                                 \

do {                                                                    \

  unsigned64 alu64subc_val = (VAL);                                     \

  ALU64_ADDC_C (~alu64subc_val, 1);                                     \

} while (0)

#define ALU_SUBC XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SUBC)

/* Compound operation - subtract carrying (and overflowing), extended */

#define ALU8_SUBC_X(VAL,C)                                              \

do {                                                                    \

  unsigned8 alu8subcx_val = (VAL);                                      \

  unsigned8 alu8subcx_c = (C);                                          \

  ALU8_ADDC_C (~alu8subcx_val, alu8subcx_c);                            \

} while (0)

#define ALU16_SUBC_X(VAL,C)                                             \

do {                                                                    \

  unsigned16 alu16subcx_val = (VAL);                                    \

  unsigned16 alu16subcx_c = (C);                                        \

  ALU16_ADDC_C (~alu16subcx_val, alu16subcx_c);                         \

} while (0)

#define ALU32_SUBC_X(VAL,C)                                             \

do {                                                                    \

  unsigned32 alu32subcx_val = (VAL);                                    \

  unsigned32 alu32subcx_c = (C);                                        \

  ALU32_ADDC_C (~alu32subcx_val, alu32subcx_c);                         \

} while (0)

#define ALU64_SUBC_X(VAL,C)                                             \

do {                                                                    \

  unsigned64 alu64subcx_val = (VAL);                                    \

  unsigned64 alu64subcx_c = (C);                                        \

  ALU64_ADDC_C (~alu64subcx_val, alu64subcx_c);                         \

} while (0)

#define ALU_SUBC_X XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SUBC_X)

/* Basic operation - subtract borrowing (and overflowing) */

#define ALU8_SUBB(VAL)                                                  \

do {                                                                    \

  unsigned8 alu8subb_val = (VAL);                                       \

  alu8_cr -= (unsigned)(unsigned8)alu8subb_val;                         \

  alu8_vr -= (signed)(signed8)alu8subb_val;                             \

} while (0)

#define ALU16_SUBB(VAL)                                                 \

do {                                                                    \

  unsigned16 alu16subb_val = (VAL);                                     \

  alu16_cr -= (unsigned)(unsigned16)alu16subb_val;                      \

  alu16_vr -= (signed)(signed16)alu16subb_val;                          \

} while (0)

#define ALU32_SUBB(VAL)                                                 \

do {                                                                    \

  unsigned32 alu32subb_val = (VAL);                                     \

  unsigned32 alu32subb_sign = alu32subb_val ^ alu32_r;                  \

  alu32_c = (alu32_r < alu32subb_val);                                  \

  alu32_r -= (alu32subb_val);                                           \

  alu32_v = ((alu32subb_sign ^ - (unsigned32)alu32_c) ^ alu32_r) >> 31; \

} while (0)

#define ALU64_SUBB(VAL)                                                 \

do {                                                                    \

  unsigned64 alu64subb_val = (VAL);                                     \

  unsigned64 alu64subb_sign = alu64subb_val ^ alu64_r;                  \

  alu64_c = (alu64_r < alu64subb_val);                                  \

  alu64_r -= (alu64subb_val);                                           \

  alu64_v = ((alu64subb_sign ^ - (unsigned64)alu64_c) ^ alu64_r) >> 31; \

} while (0)

#define ALU_SUBB XCONCAT3(ALU,WITH_TARGET_WORD_BITSIZE,_SUBB)

/* Compound operation - subtract borrowing (and overflowing) with borrow-in */

#define ALU8_SUBB_B(VAL,B)                                              \

do {                                                                    \

  unsigned8 alu8subbb_val = (VAL);                                      \

  unsigned8 alu8subbb_b = (B);                                          \