synth/tools/cc.py
2021-02-18 21:27:20 -08:00

1040 lines
30 KiB
Python

import argparse
import collections
import contextlib
import importlib
import io
import re
import subprocess
import sys
import lark
asmod = importlib.import_module("as")
GRAMMAR_FILE = '/home/paulmathieu/vhdl/tools/cc.ebnf'
CPP = ('cpp', '-P')
class Scope:
def __init__(self):
self.symbols = {}
self.parent = None
class Variable:
def __init__(self, type, name, volatile=False, addr_reg=None):
self.type = type
self.name = name
self.volatile = volatile
self.addr_reg = addr_reg
def __repr__(self):
return f'<Var: {self.type} {self.name}>'
@classmethod
def from_def(cls, tree):
volatile = False
type = tree.children[0]
if isinstance(type, lark.Tree):
for c in type.children:
if c == "volatile":
volatile = True
name = tree.children[1]
return cls(type, name, volatile=volatile)
@classmethod
def from_dereference(cls, reg):
return cls('deref', 'deref', addr_reg=reg)
# - all registers pointing to unwritten stuff can be dropped as soon as we're
# done with them:
# - already fed them into the operations
# - end of statement
# - maybe should have a separate storeage for special registers?
# need ways to:
# - assign a list of registers into r0, ... rn for function call
# - ... and run all callbacks
# - get the register for an identifier
# - dereference an expression:
# - essentially turn a temp into an lvalue-address
# - if read, need a second reg for its value
# - mark a variable to have its address in a register
# - delay reading the identifier if it's lhs
# - store the value to memory when registers are claimed
# - if it was modified through:
# - assignment
# - pre-post *crement
# - retrieve the memory type:
# - stack
# - absolute
# - register
# - or just store the value when the variable is assigned
# - get a temporary register
# - return it
# - I guess dereferencing is an upgrade
def type(self, tree):
print(tree)
class RegBank:
def __init__(self, logger=None):
self.reset()
self.log = logger or print
def reset(self):
self.available = [f'r{i}' for i in range(12)]
self.vars = {}
self.varregs = {}
self.cleanup = collections.defaultdict(list)
def take(self, reg=None):
if reg is not None:
if reg not in self.available:
self.evict(self.var(reg))
self.available.remove(reg)
return reg
if not self.available:
assert self.vars, "nothing to clean, no more regs :/"
# storing one random var
var = list(self.vars.keys())[0]
self.evict(var)
return self.available.pop(0)
def give(self, reg):
if reg in self.varregs:
# Need to call evict() with the var to free it.
return
self.available.insert(0, reg)
def loaded(self, var, reg, cleanup=None):
"""Tells the regbank some variable was loaded into the given register."""
self.vars[var] = reg
self.varregs[reg] = var
self.take(reg)
if cleanup is not None:
self.log(f'recording cleanup for {reg}({var.name})')
self.cleanup[reg].append(cleanup)
def stored(self, var):
"""Tells the regbank the given var was stored to memory, register can be freed."""
assert var in self.vars
reg = self.vars.pop(var)
del self.varregs[reg]
self.give(reg)
def load(self, var):
"""Returns the reg associated with the var, or a new reg if none was,
and True if the var was created, False otherwise."""
self.log(f'vars: {self.vars}, varregs: {self.varregs}')
if var not in self.vars:
reg = self.take()
self.vars[var] = reg
self.varregs[reg] = var
return reg, True
return self.vars[var], False
def assign(self, var, reg, cleanup=None):
"""Assign a previously-used register to a variable."""
if var in self.vars:
self.stored(var)
if reg in self.varregs:
for cb in self.cleanup.pop(reg, []):
cb(reg)
self.stored(self.varregs[reg])
self.vars[var] = reg
self.varregs[reg] = var
if cleanup is not None:
self.cleanup[reg].append(cleanup)
def var(self, reg):
return self.varregs.get(reg, None)
def evict(self, var):
"""Runs var callbacks & frees the register."""
if var not in self.vars:
return
reg = self.vars[var]
for cb in self.cleanup.pop(var, []):
cb(reg)
self.stored(var)
def flush_all(self):
for reg in list(self.cleanup):
self.log(f'flushing {reg}({self.varregs[reg].name})')
for cb in self.cleanup.pop(reg):
cb(reg)
self.reset()
def swapped(self, reg0, reg1):
var0 = self.varregs.get(reg0, None)
var1 = self.varregs.get(reg1, None)
if var0 is not None:
self.stored(var0)
elif reg0 not in self.available:
self.give(reg0)
if var1 is not None:
self.stored(var1)
elif reg1 not in self.available:
self.give(reg1)
if var0 is not None:
self.loaded(var0, reg1)
if var1 is not None:
self.loaded(var1, reg0)
@contextlib.contextmanager
def borrow(self, howmany):
regs = [self.take() for i in range(howmany)]
yield regs
for reg in regs:
self.give(reg)
class FunctionSpec:
def __init__(self, fun_prot):
self.return_type = fun_prot.children[0]
self.name = fun_prot.children[1]
self.param_types = [x.children[0] for x in fun_prot.children[2:]]
def __repr__(self):
params = ', '.join(self.param_types)
return f'<Function: {self.return_type} {self.name}({params})>'
class Function:
def __init__(self, fun_prot):
self.locals = {}
self.spec = FunctionSpec(fun_prot)
self.params = [Variable(*x.children) for x in fun_prot.children[2:]]
self.ret = None
self.nextstack = 0
self.statements = []
self.regs = RegBank(logger=self.log)
self.deferred_ops = []
self.fun_calls = 0
self.ops = []
def log(self, line):
self.ops.append(lambda: [f'// {line}'])
@property
def stack_usage(self):
return self.nextstack + 2
def get_stack(self, size=2):
stk = self.nextstack
self.nextstack += size
return stk
def param_dict(self):
return {p.name: p for p in self.params}
def __repr__(self):
return repr(self.spec)
def synth(self):
if self.fun_calls > 0:
preamble = [f'store lr, [sp, -2]',
f'set r4, {self.stack_usage}',
f'sub sp, sp, r4']
else:
preamble = []
ops = preamble
for op in self.ops:
ops += op()
indented = [f' {x}' if x[-1] == ':' else f' {x}' for x in ops]
return [f'.global {self.spec.name}',
f'{self.spec.name}:'] + indented
class CcTransform(lark.visitors.Transformer):
def _binary_op(litt):
@lark.v_args(tree=True)
def _f(self, tree):
left, right = tree.children
if left.data == 'litteral' and right.data == 'litteral':
tree.data = 'litteral'
tree.children = [litt(left.children[0], right.children[0])]
return tree
return _f
def array_item(self, children):
# transform blarg[foo] into *(blarg + foo) because reasons
addop = lark.Tree('add', children)
return lark.Tree('dereference', [addop])
# operations on litterals can be done by the compiler
add = _binary_op(lambda a, b: a+b)
sub = _binary_op(lambda a, b: a-b)
mul = _binary_op(lambda a, b: a*b)
shl = _binary_op(lambda a, b: a<<b)
CHARACTER = lambda _, x: ord(x[1])
IDENTIFIER = str
SIGNED_NUMBER = int
HEX_LITTERAL = lambda _, x: int(x[2:], 16)
class AsmOp:
scratch_need = 0
def synth(self, scratches):
return [f'nop']
@property
def out(self):
return None
class Reg:
scratch_need = 0
def __init__(self, reg):
self.out = reg
def synth(self, scratches):
return []
class BinOp(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.fun = fun
self.dest, self.left, self.right = ops
@property
def out(self):
return self.dest
def make_cpu_bin_op(cpu_op):
class _C(BinOp):
def synth(self, _):
return [f'{cpu_op} {self.dest}, {self.left}, {self.right}']
return _C
AddOp = make_cpu_bin_op('add')
SubOp = make_cpu_bin_op('sub')
MulOp = make_cpu_bin_op('mul')
# no div
# no mod either
AndOp = make_cpu_bin_op('and')
orOp = make_cpu_bin_op('or')
XorOp = make_cpu_bin_op('xor')
class ShlOp(BinOp):
scratch_need = 3
def synth(self, scratches):
sc0, sc1, sc2 = scratches
return [f'or {sc0}, {self.right}, {self.right}',
f'or {self.dest}, {self.left}, {self.left}',
f'set {sc1}, 1',
f'set {sc2}, 0',
f'cmp {sc0}, {sc2}',
f'beq [pc, 6]',
f'add {self.dest}, {self.dest}, {self.dest}',
f'sub {sc0}, {sc0}, {sc1}',
f'bneq [pc, -6]']
class LtOp(BinOp):
scratch_need = 1
def synth(self, scratches):
sc0 = scratches[0]
return [f'set {self.dest}, 0',
f'sub {sc0}, {self.left}, {self.right}',
f'bneq [pc, 2]',
f'set {self.dest}, 1']
class GtOp(LtOp):
def __init__(self, fun, ops):
dest, left, right = ops
super(GtOp, self).__init__(fun, [dest, right, left])
class UnOp(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.fun = fun
self.dest, self.operand = ops
@property
def out(self):
return self.dest
class Incr(UnOp):
scratch_need = 1
def synth(self, scratches):
sc0 = scratches[0]
return [f'set {sc0}, 1',
f'add {self.dest}, {self.operand}, {sc0}',
f'or {self.operand}, {self.dest}, {self.dest}']
class NotOp(UnOp):
def synth(self, scratches):
return [f'not {self.dest}, {self.operand}']
class BoolNot(UnOp):
def synth(self, scratches):
return [f'set {self.dest}, 0',
f'cmp {self.dest}, {self.operand}',
f'bneq [pc, 2]',
f'set {self.dest}, 1']
class NeqOp(BinOp):
def synth(self, scratches):
return [f'sub {self.dest}, {self.left}, {self.right}']
class FnCall(AsmOp):
scratch_need = 1
def __init__(self, fun, ops):
self.fun = fun
self.dest_fn, self.params = ops
@property
def out(self):
return 'r0'
def synth(self, scratches):
out = []
sc0 = scratches[0]
fn = self.dest_fn
return out + [f'set {sc0}, 2',
f'add lr, pc, {sc0}',
f'or pc, {fn}, {fn}']
class ReturnReg(AsmOp):
scratch_need = 1
def __init__(self, fun, ops):
self.fun = fun
(self.ret_reg,) = ops
def synth(self, scratches):
if self.fun.fun_calls == 0:
return [f'or r0, {self.ret_reg}, {self.ret_reg}',
f'or pc, lr, lr']
sc0 = scratches[0]
stack_usage = self.fun.stack_usage
ret = self.ret_reg
assert stack_usage < 255
return [f'set {sc0}, {stack_usage}',
f'add sp, sp, {sc0}',
f'or r0, {ret}, {ret}',
f'load pc, [sp, -2] // return']
class Load(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.fun = fun
self.dest, self.var = ops
@property
def out(self):
return self.dest
def synth(self, scratches):
reg = self.dest
if self.var.name in self.fun.locals:
src = self.var.stackaddr
return [f'load {reg}, [sp, {src}]']
elif self.var.addr_reg is not None:
return [f'load {reg}, [{self.var.addr_reg}]']
else:
return [f'set {reg}, {self.var.name}',
f'nop // in case we load a far global',
f'load {reg}, [{reg}]']
class Store(AsmOp):
scratch_need = 1
def __init__(self, fun, ops):
self.fun = fun
self.src, self.var = ops
@property
def out(self):
return None
def synth(self, scratches):
(sc,) = scratches
reg = self.src
if self.var.name in self.fun.locals:
dst = self.var.stackaddr
self.fun.log(f'storing {self.var}({reg}) to [sp, {dst}]')
return [f'store {reg}, [sp, {dst}]']
elif self.var.addr_reg is not None:
return [f'store {reg}, [{self.var.addr_reg}]']
return [f'set {sc}, {self.var.name}',
f'nop // you know, in case blah',
f'store {reg}, [{sc}]']
class Assign(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.fun = fun
self.src, self.var = ops
@property
def out(self):
return self.var
def synth(self, scratches):
return [f'or {self.var}, {self.src}, {self.src}']
class SetAddr(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.dest, self.ident = ops
@property
def out(self):
return self.dest
def synth(self, scratches):
reg = self.dest
return [f'set {reg}, {self.ident}',
f'nop // placeholder for a long address']
class Set16Imm(AsmOp):
scratch_need = 0
def __init__(self, fun, ops):
self.dest, self.imm16 = ops
@property
def out(self):
return self.dest
def synth(self, scratches):
reg = self.dest
hi = (self.imm16 >> 8) & 0xff
lo = (self.imm16 >> 0) & 0xff
if hi != 0:
return [f'set {reg}, {lo}',
f'seth {reg}, {hi}']
else:
return [f'set {reg}, {lo}']
class Swap(AsmOp):
scratch_need = 1
def __init__(self, a0, a1):
self.a0 = a0
self.a1 = a1
def synth(self, scratches):
(sc0,) = scratches
return [f'or {sc0}, {self.a0}, {self.a0}',
f'or {self.a0}, {self.a1}, {self.a1}',
f'or {self.a1}, {sc0}, {sc0}']
class IfOp(AsmOp):
scratch_need = 1
def __init__(self, fun, op):
self.fun = fun
self.cond, mark, self.has_else = op
self.then_mark = f'_then_{mark}'
self.else_mark = f'_else_{mark}'
self.endif_mark = f'_endif_{mark}'
def synth(self, scratches):
sc0 = scratches[0]
if self.has_else:
return [f'set {sc0}, 0',
f'cmp {sc0}, {self.cond}', # flag if cond == 0
f'beq {self.else_mark}']
else:
return [f'set {sc0}, 0',
f'cmp {sc0}, {self.cond}',
f'beq {self.endif_mark}']
def synth_else(self):
return [f'cmp r0, r0', # trick because beq is better than "or pc, ."
f'beq {self.endif_mark}',
f'{self.else_mark}:']
def synth_endif(self):
return [f'{self.endif_mark}:']
class WhileOp(AsmOp):
scratch_need = 1
@staticmethod
def synth_loop(mark):
loop_mark = f'_loop_{mark}'
return [f'{loop_mark}:']
def __init__(self, cond, mark):
self.cond = cond
self.loop_mark = f'_loop_{mark}'
self.endwhile_mark = f'_endwhile_{mark}'
def synth(self, scratches):
sc0 = scratches[0]
return [f'set {sc0}, 0',
f'cmp {sc0}, {self.cond}',
f'beq {self.endwhile_mark}']
def synth_endwhile(self):
return [f'cmp r0, r0',
f'beq {self.loop_mark}',
f'{self.endwhile_mark}:']
class Delayed(AsmOp):
def __init__(self, out_cb):
self.out_cb = out_cb
@property
def out(self):
return self.out_cb()
def synth(self):
return []
class CcInterp(lark.visitors.Interpreter):
def __init__(self):
self.global_scope = Scope()
self.cur_scope = self.global_scope
self.cur_fun = None
self.funs = []
self.next_reg = 0
self.next_marker = 0
def _lookup_symbol(self, s):
scope = self.cur_scope
while scope is not None:
if s in scope.symbols:
return scope.symbols[s]
scope = scope.parent
return None
def _get_reg(self):
return self.cur_fun.regs.take()
def _get_marker(self):
mark = self.next_marker
self.next_marker += 1
return mark
def _synth(self, op):
with self.cur_fun.regs.borrow(op.scratch_need) as scratches:
self._log(f'{op.__class__.__name__}')
self.cur_fun.ops.append(lambda: op.synth(scratches))
def _load(self, ident):
s = self._lookup_symbol(ident)
assert s is not None, f'unknown identifier {ident}'
if isinstance(s, FunctionSpec) or s in self.global_scope.symbols:
reg = self._get_reg()
return SetAddr(self.cur_fun, [reg, ident])
else:
if s.volatile:
self._log(f'loading volatile {s}')
return Load(self.cur_fun, [reg, s])
reg, created = self.cur_fun.regs.load(s)
if created:
return Load(self.cur_fun, [reg, s])
else:
self._log(f'{s} was already in {reg}')
return Reg(reg)
def identifier(self, tree):
# TODO: not actually load the value until it's used in an expression
# could have the op.out() function have a side effect that does that
# if it's an assignment, we need to make a Variable with the proper
# address and assign the register to it.
# If it's volatile, we need to flush it.
def delayed_load():
self._log(f'delay-loading {tree.children[0]}')
op = self._load(tree.children[0])
self._synth(op)
return op.out
tree.op = Delayed(delayed_load)
tree.var = self._lookup_symbol(tree.children[0])
def litteral(self, tree):
imm = tree.children[0]
reg = self._get_reg()
assert self.cur_fun is not None
tree.op = Set16Imm(self.cur_fun, [reg, imm])
self._synth(tree.op)
def _assign(self, left, right):
# need to make sure there's a variable and either:
# - to store it, or
# - to mark a register for it
if left.volatile:
self._synth(Store(self.cur_fun, [right, left]))
self.cur_fun.stored(left)
return
self._log(f'assigning {left} = {right}')
# cleanup = lambda reg: self._synth(Store(self.cur_fun, [reg, left]))
self.cur_fun.regs.assign(left, right)
self._synth(Store(self.cur_fun, [right, left]))
def assignment(self, tree):
self.visit_children(tree)
val = tree.children[1].op.out
# left hand side is an lvalue, retrieve it
var = tree.children[0].var
self._assign(var, val)
def global_var(self, tree):
self.visit_children(tree)
var = Variable.from_def(tree)
self.global_scope.symbols[var.name] = var
val = 0
if len(tree.children) > 2:
val = tree.children[2].children[0].value
def fun_decl(self, tree):
fun = FunctionSpec(tree.children[0])
self.cur_scope.symbols[fun.name] = fun
def _prep_fun_call(self, fn_reg, params):
"""Move all params to r0-rn."""
def swap(old, new):
if old == new:
return
oldpos = params.index(old)
try:
newpos = params.index(new)
except ValueError:
params[oldpos] = new
else:
params[newpos], params[oldpos] = params[oldpos], params[newpos]
self._synth(Swap(old, new))
if fn_reg in [f'r{i}' for i in range(len(params))]:
new_fn = f'r{len(params)}'
self._synth(Swap(fn_reg, new_fn))
fn_reg = new_fn
for i, param in enumerate(params):
new = f'r{i}'
swap(param, new)
return fn_reg
def fun_call(self, tree):
self.cur_fun.fun_calls += 1
self.visit_children(tree)
fn_reg = tree.children[0].op.out
param_regs = [c.op.out for c in tree.children[1:]]
self.cur_fun.regs.flush_all()
for i in range(len(param_regs)):
self.cur_fun.regs.take(f'r{i}')
fn_reg = self._prep_fun_call(fn_reg, param_regs)
self.cur_fun.regs.take(fn_reg)
tree.op = FnCall(self.cur_fun, [fn_reg, param_regs])
self._synth(tree.op)
self.cur_fun.regs.reset()
self.cur_fun.regs.take('r0')
def statement(self, tree):
self.visit_children(tree)
if self.cur_fun.deferred_ops:
self._log(f'deferred logic: {len(self.cur_fun.deferred_ops)}')
for op in self.cur_fun.deferred_ops:
self._synth(op)
self.cur_fun.deferred_ops = []
iter_expression = statement
def if_stat(self, tree):
self.visit(tree.children[0])
mark = self._get_marker()
has_else = len(tree.children) > 2
op = IfOp(self.cur_fun, [tree.children[0].op.out, mark, has_else])
self._synth(op)
self.visit(tree.children[1])
if has_else:
self.cur_fun.ops.append(op.synth_else)
self.visit(tree.children[2])
self.cur_fun.ops.append(op.synth_endif)
def while_stat(self, tree):
mark = self._get_marker()
self.cur_fun.ops.append(lambda: WhileOp.synth_loop(mark))
begin_vars = dict(self.cur_fun.regs.vars)
self.visit(tree.children[0])
op = WhileOp(tree.children[0].op.out, mark)
self._synth(op)
self.visit(tree.children[1])
for v, r in begin_vars.items():
rvars = self.cur_fun.regs.vars
if v not in rvars or rvars[v] != r:
self._log(f'loading missing var {v}')
self._synth(Load(self.cur_fun, [r, v]))
self.cur_fun.ops.append(op.synth_endwhile)
def for_stat(self, tree):
mark = self._get_marker()
self.visit(tree.children[0]) # initialization
self.cur_fun.ops.append(lambda: WhileOp.synth_loop(mark))
begin_vars = dict(self.cur_fun.regs.vars)
self.visit(tree.children[1])
op = WhileOp(tree.children[1].op.out, mark)
self._synth(op)
self.visit(tree.children[3])
self.visit(tree.children[2]) # 3rd statement
for v, r in begin_vars.items():
rvars = self.cur_fun.regs.vars
if v not in rvars or rvars[v] != r:
self._log(f'loading missing var {v}')
self._synth(Load(self.cur_fun, [r, v]))
self.cur_fun.ops.append(op.synth_endwhile)
def _unary_op(op):
def _f(self, tree):
self.visit_children(tree)
operand = tree.children[0].op.out
reg = self.cur_fun.regs.take()
tree.op = op(self.cur_fun, [reg, operand])
self._synth(tree.op)
self.cur_fun.regs.give(operand)
return _f
def dereference(self, tree):
self.visit_children(tree)
reg = tree.children[0].op.out
var = Variable.from_dereference(reg)
self._log(f'making var {var} from derefing reg {reg}')
tree.var = var
def delayed_load():
self._log(f'delay-loading {tree.children[0]}')
op = Load(self.cur_fun, [reg, var])
self._synth(op)
return op.out
tree.op = Delayed(delayed_load)
def post_increment(self, tree):
self.visit_children(tree)
tree.op = Reg(tree.children[0].op.out)
var = tree.children[0].var
reg = tree.op.out
self.cur_fun.deferred_ops.append(Incr(self.cur_fun, [reg, reg]))
self.cur_fun.deferred_ops.append(Store(self.cur_fun, [reg, var]))
pre_increment = _unary_op(Incr)
bool_not = _unary_op(BoolNot)
def _binary_op(op):
def _f(self, tree):
self.visit_children(tree)
left, right = (x.op.out for x in tree.children)
dest = self.cur_fun.regs.take()
tree.op = op(self.cur_fun, [dest, left, right])
self._synth(tree.op)
self.cur_fun.regs.give(left)
self.cur_fun.regs.give(right)
return _f
def _combo(uop, bop):
def _f(self, tree):
bop.__get__(self)(tree)
uop.__get__(self)(tree)
return _f
shl = _binary_op(ShlOp)
add = _binary_op(AddOp)
sub = _binary_op(SubOp)
mul = _binary_op(MulOp)
_and = _binary_op(AndOp)
# ...
gt = _binary_op(GtOp)
lt = _binary_op(LtOp)
neq = _binary_op(NeqOp)
eq = _combo(bool_not, neq)
def _forward_op(self, tree):
self.visit_children(tree)
tree.op = tree.children[0].op
def cast(self, tree):
self.visit_children(tree)
tree.op = tree.children[1].op
def _log(self, line):
self.cur_fun.log(line)
def local_var(self, tree):
self.visit_children(tree)
assert self.cur_fun is not None
assert self.cur_scope is not None
var = Variable.from_def(tree)
var.stackaddr = self.cur_fun.get_stack() # will have to invert
self.cur_scope.symbols[var.name] = var
self.cur_fun.locals[var.name] = var
if len(tree.children) > 2:
initval = tree.children[2].children[0].op.out
cleanup = lambda reg: self._synth(Store(self.cur_fun, [reg, var]))
self.cur_fun.regs.assign(var, initval, cleanup)
self._log(f'assigning {var} = {initval}')
def fun_def(self, tree):
prot, body = tree.children
fun = Function(prot)
assert self.cur_fun is None
self.cur_fun = fun
self.cur_scope.symbols[fun.spec.name] = fun.spec
params = fun.param_dict()
def getcleanup(var):
return lambda reg: self._synth(Store(self.cur_fun, [reg, var]))
for i, param in enumerate(fun.params):
fun.locals[param.name] = param
param.stackaddr = fun.get_stack()
self._log(f'param [sp, {param.stackaddr}]: {param.name} in r{i}')
cleanup = getcleanup(param)
fun.regs.loaded(param, f'r{i}', cleanup)
fun_scope = Scope()
fun_scope.parent = self.cur_scope
fun_scope.symbols.update(params)
body.scope = fun_scope
self.visit_children(tree)
if fun.ret is None:
if fun.spec.name == 'main':
self._synth(Set16Imm(fun, ['r0', 0]))
self._synth(ReturnReg(fun, ['r0']))
elif fun.spec.return_type == 'void':
self._synth(ReturnReg(fun, ['r0']))
else:
assert fun.ret is not None
self.cur_fun = None
self.funs.append(fun)
def body(self, tree):
bscope = getattr(tree, 'scope', Scope())
bscope.parent = self.cur_scope
self.cur_scope = bscope
self.visit_children(tree)
self.cur_scope = bscope.parent
def return_stat(self, tree):
assert self.cur_fun is not None
self.cur_fun.ret = True
self.visit_children(tree)
expr_reg = tree.children[0].op.out
tree.op = ReturnReg(self.cur_fun, [expr_reg])
self._synth(tree.op)
preamble = [f'_start:',
f'xor r0, r0, r0',
f'xor r1, r1, r1',
f'set sp, 0',
f'seth sp, {0x11}', # 256 bytes of stack ought to be enough
f'set r2, main',
f'set r3, 2',
f'add lr, pc, r3',
f'or pc, r2, r2',
f'or pc, pc, pc // loop forever',
]
def filter_dupes(ops):
dupe_re = re.compile(r'or (r\d+), \1, \1')
for op in ops:
if dupe_re.search(op):
continue
yield op
def parse_tree(tree, debug=False):
tr = CcTransform()
tree = tr.transform(tree)
if debug:
print(tree.pretty())
inte = CcInterp()
inte.visit(tree)
out = []
for fun in inte.funs:
out += fun.synth()
out.append('')
return '\n'.join(filter_dupes(out))
def larkparse(f, debug=False):
with open(GRAMMAR_FILE) as g:
asparser = lark.Lark(g.read())
data = f.read()
if isinstance(data, bytes):
data = data.decode()
tree = asparser.parse(data)
return parse_tree(tree, debug=debug)
def parse_args():
parser = argparse.ArgumentParser(description='Compile.')
parser.add_argument('--debug', action='store_true',
help='print the AST')
parser.add_argument('--assembly', '-S', action='store_true',
help='output assembly')
parser.add_argument('--compile', '-c', action='store_true',
help='compile a single file')
parser.add_argument('input', type=argparse.FileType('r'),
default=sys.stdin, help='input file (default: stdin)')
parser.add_argument('--output', '-o', type=argparse.FileType('wb'),
default=sys.stdout.buffer, help='output file')
return parser.parse_args()
def preprocess(fin):
p = subprocess.Popen(CPP, stdin=fin, stdout=subprocess.PIPE)
return p.stdout
def assemble(text, fout):
fin = io.StringIO(text)
asmod.write_obj(fout, *asmod.larkparse(fin))
def main():
args = parse_args()
assy = larkparse(preprocess(args.input), debug=args.debug)
if args.assembly:
args.output.write(assy.encode() + b'\n')
else:
assemble(assy, args.output)
if __name__ == "__main__":
main()