float.syn

#
# FastBasic - Fast basic interpreter for the Atari 8-bit computers
# Copyright (C) 2017-2025 Daniel Serpell
#
# 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, see <http://www.gnu.org/licenses/>
#


# Floating point computations
TOKENS {
 TOK_INT_FP, TOK_FP_VAL, TOK_FP_SGN, TOK_FP_ABS, TOK_FP_NEG, TOK_FLOAT
 TOK_FP_DIV, TOK_FP_MUL, TOK_FP_SUB, TOK_FP_ADD, TOK_FP_STORE, TOK_FP_LOAD
 TOK_FP_EXP, TOK_FP_EXP10, TOK_FP_LOG, TOK_FP_LOG10, TOK_FP_INT, TOK_FP_CMP
 TOK_FP_IPOW, TOK_FP_RND, TOK_FP_SQRT, TOK_FP_SIN, TOK_FP_COS, TOK_FP_ATN
 TOK_FP_STR, TOK_FP_TIME
 # Used for floating point array access
 TOK_MUL6
}

# And parsing functions
EXTERN {
 E_NUMBER_FP
}

SYMBOLS {
 VT_ARRAY_FLOAT = importzp
 VT_FLOAT       = importzp
 DEGFLAG = importzp
}

# Floating point expressions
FP_EXPR: floating point expression
        FP_T_EXPR FP_E_EXPR_MORE FP_M_EXPR_MORE FP_EXPR_MORE

FP_EXPR_MORE:
        "+" FP_T_EXPR FP_E_EXPR_MORE FP_M_EXPR_MORE emit TOK_FP_ADD FP_EXPR_MORE
        "-" FP_T_EXPR FP_E_EXPR_MORE FP_M_EXPR_MORE emit TOK_FP_SUB FP_EXPR_MORE
        pass

FP_M_EXPR_MORE:
        "*" FP_T_EXPR FP_E_EXPR_MORE emit TOK_FP_MUL FP_M_EXPR_MORE
        "/" FP_T_EXPR FP_E_EXPR_MORE emit TOK_FP_DIV FP_M_EXPR_MORE
        pass

FP_E_EXPR_MORE:
        "^" T_EXPR emit TOK_FP_IPOW FP_E_EXPR_MORE
        "^" emit TOK_FP_LOG10 FP_T_EXPR emit { TOK_FP_MUL, TOK_FP_EXP10 } FP_E_EXPR_MORE
        pass

FP_T_EXPR: floating point constant, variable or function
        emit TOK_FLOAT E_NUMBER_FP
        "-" FP_T_EXPR emit TOK_FP_NEG
        "+" FP_T_EXPR
        FP_FUNCS
        "(" FP_EXPR ")"
        ARRAY_FLOAT_ADDR emit TOK_FP_LOAD
        INT_FUNCTIONS emit TOK_INT_FP

FP_FUNCS:
        # FP Functions
        "Abs"   FP_T_EXPR emit TOK_FP_ABS
        "ATn"   FP_T_EXPR emit TOK_FP_ATN
        "SGn"   FP_T_EXPR emit TOK_FP_SGN
        "EXp10" FP_T_EXPR emit TOK_FP_EXP10
        "EXP"   FP_T_EXPR emit TOK_FP_EXP
        "LOg10" FP_T_EXPR emit TOK_FP_LOG10
        "LOG"   FP_T_EXPR emit TOK_FP_LOG
        "SQr"   FP_T_EXPR emit TOK_FP_SQRT
        "SIn"   FP_T_EXPR emit TOK_FP_SIN
        "COs"   FP_T_EXPR emit TOK_FP_COS
        "Val"   STR_EXPR emit TOK_FP_VAL
        "RNd()" emit TOK_FP_RND
        "%Time" emit TOK_FP_TIME

ADR_EXPR:
        emit { TOK_VAR_LOAD, VT_ARRAY_FLOAT } E_VAR_SEARCH "%"
        emit { TOK_VAR_ADDR, VT_FLOAT } E_VAR_SEARCH "%"
        emit { TOK_NUM, VT_ARRAY_FLOAT } E_LABEL "%"

INT_FUNCTIONS:
        "Int"    FP_T_EXPR emit TOK_FP_INT

STRING_FUNCTIONS:
        "STR$" FP_T_EXPR emit TOK_FP_STR

# FP Comparisons:
COMP_FP_RIGHT: floating-point comparison operator
        "="  FP_EXPR emit { TOK_FP_CMP, TOK_EQ }
        ">"  FP_EXPR emit { TOK_FP_CMP, TOK_GT }
        ">=" FP_EXPR emit { TOK_FP_CMP, TOK_LT, TOK_L_NOT }
        "<>" FP_EXPR emit { TOK_FP_CMP, TOK_NEQ }
        "<=" FP_EXPR emit { TOK_FP_CMP, TOK_GT, TOK_L_NOT }
        "<"  FP_EXPR emit { TOK_FP_CMP, TOK_LT }

# Adds floating-point comparisons as boolean expressions
COMP_OR_BOOL:
        emit TOK_INT_FP COMP_FP_RIGHT COMP_EXPR_MORE

TEST_BOOL_EXPR:
        emit TOK_INT_FP COMP_FP_RIGHT OR_EXPR_MORE AND_EXPR_MORE COMP_EXPR_MORE

EXPR:
        FP_EXPR COMP_FP_RIGHT

NOT_EXPR:
        FP_EXPR COMP_FP_RIGHT

# Print & Input
PRINT_ONE:
        FP_EXPR emit { TOK_FP_STR }

INPUT_VAR:
        VAR_FP_LVALUE_SADDR emit { TOK_INPUT_STR, TOK_FP_VAL, TOK_FP_STORE }

# Arrays
ARRAY_FLOAT_ADDR:
        emit { TOK_VAR_ADDR, VT_FLOAT } E_VAR_SEARCH "%"
        emit { TOK_VAR_LOAD, VT_ARRAY_FLOAT } E_VAR_SEARCH "%" emit TOK_PUSH PAR_EXPR emit { TOK_MUL6, TOK_ADD }
        emit { TOK_NUM, VT_ARRAY_FLOAT } E_LABEL "%" emit TOK_PUSH PAR_EXPR emit { TOK_MUL6, TOK_ADD }
        "%"     PAR_EXPR

# This is added at start of current table (<)
DIM_VAR_TYPE:<
        "%" PAR_EXPR emit { TOK_PUSH_1, TOK_ADD, TOK_MUL6, VT_ARRAY_FLOAT }

DIM_VAR:
        emit { VT_FLOAT } E_VAR_SEARCH "%" E_PUSH_VAR

DATA_FLOATS: data number
        "," E_NUMBER_FP DATA_FLOATS
        pass

DATA_TYPE:
        emit { VT_ARRAY_FLOAT } DATA_EXT_TYPE EQUAL E_LABEL_SET_TYPE E_NUMBER_FP DATA_FLOATS

DATA_VAR:
        E_LABEL_CREATE "%()" emit { TOK_JUMP } E_LABEL_DEF DATA_TYPE

# Can create Float variables now
VAR_CREATE_TYPE:
        "%" emit VT_FLOAT

# Variables
VAR_FP_LVALUE_SADDR: variable name
        emit { TOK_VAR_SADDR, VT_FLOAT } E_VAR_SEARCH "%"
        ARRAY_FLOAT_ADDR emit TOK_SADDR

# And statements
STATEMENT:
        "DEG" emit { TOK_1, TOK_BYTE_POKE, DEGFLAG }
        "RAd" emit { TOK_0, TOK_BYTE_POKE, DEGFLAG }

LINE_ASSIGNMENT:
        VAR_FP_LVALUE_SADDR EQUAL FP_EXPR emit TOK_FP_STORE

# vi:syntax=perl