prog8/python/il65/codegen/shared.py
2018-08-07 22:49:01 +02:00

88 lines
3.0 KiB
Python

"""
Programming Language for 6502/6510 microprocessors, codename 'Sick'
Shared logic for the code generators.
Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
"""
import math
from ..datatypes import FLOAT_MAX_POSITIVE, FLOAT_MAX_NEGATIVE
from ..plyparse import Module, Label, Block, Directive, VarDef
from ..plylex import print_bold
class CodeGenerationError(Exception):
pass
def sanitycheck(module: Module) -> None:
for label in module.all_nodes(Label):
if label.name == "start" and label.my_scope().name == "main": # type: ignore
break
else:
print_bold("ERROR: program entry point is missing ('start' label in 'main' block)\n")
raise SystemExit(1)
all_blocknames = [b.name for b in module.all_nodes(Block)] # type: ignore
unique_blocknames = set(all_blocknames)
if len(all_blocknames) != len(unique_blocknames):
for name in unique_blocknames:
all_blocknames.remove(name)
raise CodeGenerationError("there are duplicate block names", all_blocknames)
zpblock = module.zeropage()
if zpblock:
# ZP block contains no code?
for stmt in zpblock.scope.nodes:
if not isinstance(stmt, (Directive, VarDef)):
raise CodeGenerationError("ZP block can only contain directive and var")
def to_hex(number: int) -> str:
# 0..15 -> "0".."15"
# 16..255 -> "$10".."$ff"
# 256..65536 -> "$0100".."$ffff"
assert type(number) is int
if number is None:
raise ValueError("number")
if 0 <= number < 16:
return str(number)
if 0 <= number < 0x100:
return "${:02x}".format(number)
if 0 <= number < 0x10000:
return "${:04x}".format(number)
raise OverflowError(number)
def to_mflpt5(number: float) -> bytearray:
# algorithm here https://sourceforge.net/p/acme-crossass/code-0/62/tree/trunk/ACME_Lib/cbm/mflpt.a
number = float(number)
if number < FLOAT_MAX_NEGATIVE or number > FLOAT_MAX_POSITIVE:
raise OverflowError("floating point number out of 5-byte mflpt range", number)
if number == 0.0:
return bytearray([0, 0, 0, 0, 0])
if number < 0.0:
sign = 0x80000000
number = -number
else:
sign = 0x00000000
mant, exp = math.frexp(number)
exp += 128
if exp < 1:
# underflow, use zero instead
return bytearray([0, 0, 0, 0, 0])
if exp > 255:
raise OverflowError("floating point number out of 5-byte mflpt range", number)
mant = sign | int(mant * 0x100000000) & 0x7fffffff
return bytearray([exp]) + int.to_bytes(mant, 4, "big")
def mflpt5_to_float(mflpt: bytearray) -> float:
# algorithm here https://sourceforge.net/p/acme-crossass/code-0/62/tree/trunk/ACME_Lib/cbm/mflpt.a
if mflpt == bytearray([0, 0, 0, 0, 0]):
return 0.0
exp = mflpt[0] - 128
sign = mflpt[1] & 0x80
number = 0x80000000 | int.from_bytes(mflpt[1:], "big")
number = float(number) * 2**exp / 0x100000000
return -number if sign else number