async def compile(self, ctx: CompileContext) -> Register:
lhs, rhs = await self.compile_meta(ctx)
res = ctx.get_register(lhs.size, self.sign)
op = {"+": "add", "-": "sub"}[self.op]
if isinstance(await self.type, Pointer):
# adding a pointer with an integer multiplies the integer side by the pointed to type
(ptr_type, non_ptr) = ((self.left_type, rhs) if isinstance(
self.left_type, Pointer) else (self.right_type, lhs))
if isinstance(ptr_type.to, Void):
raise self.error("Cannot perform pointer arithmetic on pointer to void.")
ctx.emit(Binary.mul(non_ptr, Immediate(ptr_type.to.size, non_ptr.size)))
elif (op == "sub"
and isinstance(self.left_type, Pointer)
and isinstance(self.right_type, Pointer)):
if isinstance(self.left_type.to, Void):
raise self.error("Cannot perform pointer arithmetic on pointer to void.")
if self.left_type != self.right_type:
raise self.error("Both sides of pointer subtraction must be the same type.")
# subtracting two pointers of equal type yields the number of elements between them
ctx.emit(Binary(lhs, rhs, op, res))
ctx.emit(Binary.udiv(res, Immediate(self.left_type.to.size, res.size)))
return res
ctx.emit(Binary(lhs, rhs, op, res))
return res
async def compile_as_arr(self, ctx: CompileContext) -> Register:
"""Compile an array literal but inline the inner values."""
if (isinstance((await self.type).to, types.Array)
and (not isinstance(self.first_elem, ArrayLiteral))):
# Maybe just cast the internal type to a pointer.
raise self.error(
"Internal type is of array type but is not a literal.")
if self.var is None:
self.var = ctx.declare_unique_variable(await self.type)
self.var.lvalue_is_rvalue = True
base = ctx.get_register(types.Pointer.size)
index = ctx.get_register(types.Pointer.size)
ctx.emit(LoadVar(self.var, base))
ctx.emit(Mov(index, base))
elem_size = (await self.type).to.size
for i in self.exprs:
await i.compile_as_arr_helper(ctx, index)
# NOTE: will we ever hit this?
if self.float_size:
ctx.emit(Binary.add(index, Immediate(elem_size * self.float_size)))
return base
async def compile(self, ctx: CompileContext) -> Register:
op = {"|": "or", "^": "xor", "&": "and"}[self.op]
lhs, rhs = await self.compile_meta(ctx)
res = ctx.get_register(lhs.size, self.sign)
ctx.emit(Binary(lhs, rhs, op, res))
return res
async def compile_as_ref(self, ctx: CompileContext) -> Register:
"""Compile to the array literal and return a reference to the start.
This function is for when an array of references is the wanted outcome.
This function will not work on array types.
"""
if self.var is None:
self.var = ctx.declare_unique_variable(await self.type)
self.var.lvalue_is_rvalue = True
if (isinstance(self.first_elem, ArrayLiteral) and (not isinstance(
(await self.type).to, types.Pointer))):
raise self.error(
"Cannot compile to references if internal array type is an array and not a pointer"
)
base = ctx.get_register(types.Pointer.size)
index = ctx.get_register(types.Pointer.size)
ctx.emit(LoadVar(self.var, base))
ctx.emit(Mov(index, base))
elem_type = (await self.type).to
for i in self.exprs:
r = await i.compile(ctx)
if r.size != elem_type.size:
r0 = r.resize(elem_type.size, elem_type.signed)
ctx.emit(Resize(r, r0))
r = r0
ctx.emit(Mov(Dereference(index, r.size), r))
ctx.emit(Binary.add(index, Immediate(r.size, types.Pointer.size)))
if self.float_size:
# fill in missing values
ctx.emit(
Binary.add(
index,
Immediate(elem_type.size * self.float_size, index.size)))
return base
async def compile(self, ctx: CompileContext) -> Register:
my_type = await self.type
ptr: Register = await self.load_lvalue(ctx)
tmp = ctx.get_register(my_type.size, my_type.signed)
increment = 1
# in the case of pointer increments, increment by the size of the pointer's underlying type
if isinstance(my_type, Pointer):
increment = my_type.to.size
ctx.emit(Mov(tmp, Dereference(ptr, tmp.size)))
ctx.emit(Binary(tmp, Immediate(increment, tmp.size), self.op))
ctx.emit(Mov(Dereference(ptr, tmp.size), tmp))
return tmp
async def load_lvalue(self, ctx: CompileContext) -> Register:
atype = await self.arg.type
if not isinstance(atype, (Pointer, Array)):
raise self.error(f"Incompatible type to array index base {atype}")
# don't allow void pointer arithmetic
# This 'would' fail later with an error about requesting a register of size 0
# But that would be less informative than catching the error now.
if isinstance(atype.to, Void):
raise self.error("Cannot perform pointer arithemetic on void pointers.")
argument = await self.arg.compile(ctx)
offset = await self.offset.compile(ctx)
# get the size of the inner type if type.to is an array,
# this will be the size of the internal array
size = await self.size
# make sure both the offset and the arguments are the correct size (size of a pointer)
if argument.size != Pointer.size:
argument0 = argument.resize(Pointer.size)
ctx.emit(Resize(argument, argument0))
argument = argument0
if offset.size != Pointer.size:
offset0 = offset.resize(Pointer.size)
ctx.emit(Resize(offset, offset0))
offset = offset0
result = ctx.get_register(Pointer.size)
# multiply to the size of the inner type of the pointer/ array
ctx.emit(Binary.mul(offset, Immediate(size, offset.size)))
ctx.emit(Binary.add(argument, offset, result))
return result
async def compile_as_arr_helper(self, ctx: CompileContext, base: Register):
if isinstance(self.first_elem, ArrayLiteral) and isinstance(
await self.type, types.Array):
for i in self.exprs:
await i.compile_as_arr_helper(ctx, base)
else:
elem_type = (await self.type).to
for i in self.exprs:
r = await i.compile(ctx)
if r.size != elem_type.size:
r0 = r.resize(elem_type.size, elem_type.signed)
ctx.emit(Resize(r, r0))
r = r0
ctx.emit(Mov(Dereference(base, r.size), r))
ctx.emit(
Binary.add(base, Immediate(r.size, types.Pointer.size)))
async def compile(self, ctx: CompileContext) -> Register:
my_type = await self.type
ptr: Register = await self.arg.load_lvalue(ctx)
size = my_type.size
res, temp = (ctx.get_register(size, my_type.signed),
ctx.get_register(size))
increment = 1
if isinstance(my_type, Pointer):
increment = my_type.to.size
ctx.emit(Mov(res, Dereference(ptr, res.size)))
ctx.emit(Binary(res, Immediate(increment, size), self.op, temp))
ctx.emit(Mov(Dereference(ptr, temp.size), temp))
return res
async def compile(self, ctx: CompileContext) -> Register:
lhs, rhs = await self.compile_meta(ctx)
if rhs.sign:
raise self.right.error(
"RHS operand to a binary shift op must be unsigned.")
res = ctx.get_register(lhs.size, self.sign)
if self.op == "<<":
op = "shl"
elif self.op == ">>" and lhs.sign:
op = "sar"
else:
op = "shr"
ctx.emit(Binary(lhs, rhs, op, res))
return res
async def compile(self, ctx: CompileContext) -> Register:
lhs, rhs = await self.compile_meta(ctx)
res = ctx.get_register(lhs.size, self.sign)
if self.op == "*":
op = "mul"
elif self.op == "%":
if self.sign:
op = "imod"
else:
op = "umod"
elif self.op == "/" and self.sign:
op = "idiv"
else:
op = "udiv"
ctx.emit(Binary(lhs, rhs, op, res))
return res