mirror of
https://github.com/varun-r-mallya/Python-BPF.git
synced 2025-12-31 21:06:25 +00:00
82 lines
2.7 KiB
Python
82 lines
2.7 KiB
Python
import ast
|
|
from llvmlite import ir
|
|
from logging import Logger
|
|
import logging
|
|
|
|
logger: Logger = logging.getLogger(__name__)
|
|
|
|
|
|
def deref_to_val(var, builder):
|
|
"""Dereference a variable to get its value and pointer chain."""
|
|
logger.info(f"Dereferencing {var}, type is {var.type}")
|
|
|
|
chain = [var]
|
|
cur = var
|
|
|
|
while isinstance(cur.type, ir.PointerType):
|
|
cur = builder.load(cur)
|
|
chain.append(cur)
|
|
|
|
if isinstance(cur.type, ir.IntType):
|
|
logger.info(f"dereference chain: {chain}")
|
|
return cur, chain
|
|
else:
|
|
raise TypeError(f"Unsupported type for dereferencing: {cur.type}")
|
|
|
|
|
|
def get_operand_value(operand, builder, local_sym_tab):
|
|
"""Extract the value from an operand, handling variables and constants."""
|
|
if isinstance(operand, ast.Name):
|
|
if operand.id in local_sym_tab:
|
|
var = local_sym_tab[operand.id].var
|
|
val, chain = deref_to_val(var, builder)
|
|
return val, chain, var
|
|
raise ValueError(f"Undefined variable: {operand.id}")
|
|
elif isinstance(operand, ast.Constant):
|
|
if isinstance(operand.value, int):
|
|
cst = ir.Constant(ir.IntType(64), operand.value)
|
|
return cst, [cst], None
|
|
raise TypeError(f"Unsupported constant type: {type(operand.value)}")
|
|
elif isinstance(operand, ast.BinOp):
|
|
res = handle_binary_op_impl(operand, builder, local_sym_tab)
|
|
return res, [res], None
|
|
raise TypeError(f"Unsupported operand type: {type(operand)}")
|
|
|
|
|
|
def handle_binary_op_impl(rval, builder, local_sym_tab):
|
|
op = rval.op
|
|
left, _, _ = get_operand_value(rval.left, builder, local_sym_tab)
|
|
right, _, _ = get_operand_value(rval.right, builder, local_sym_tab)
|
|
logger.info(f"left is {left}, right is {right}, op is {op}")
|
|
|
|
# Map AST operation nodes to LLVM IR builder methods
|
|
op_map = {
|
|
ast.Add: builder.add,
|
|
ast.Sub: builder.sub,
|
|
ast.Mult: builder.mul,
|
|
ast.Div: builder.sdiv,
|
|
ast.Mod: builder.srem,
|
|
ast.LShift: builder.shl,
|
|
ast.RShift: builder.lshr,
|
|
ast.BitOr: builder.or_,
|
|
ast.BitXor: builder.xor,
|
|
ast.BitAnd: builder.and_,
|
|
ast.FloorDiv: builder.udiv,
|
|
}
|
|
|
|
if type(op) in op_map:
|
|
result = op_map[type(op)](left, right)
|
|
return result
|
|
else:
|
|
raise SyntaxError("Unsupported binary operation")
|
|
|
|
|
|
def handle_binary_op(rval, builder, var_name, local_sym_tab):
|
|
result = handle_binary_op_impl(rval, builder, local_sym_tab)
|
|
if var_name and var_name in local_sym_tab:
|
|
logger.info(
|
|
f"Storing result {result} into variable {local_sym_tab[var_name].var}"
|
|
)
|
|
builder.store(result, local_sym_tab[var_name].var)
|
|
return result, result.type
|