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https://github.com/varun-r-mallya/Python-BPF.git
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56 lines
1.8 KiB
Python
56 lines
1.8 KiB
Python
import ast
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from llvmlite import ir
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class HelperHandlerRegistry:
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"""Registry for BPF helpers"""
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_handlers = {}
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@classmethod
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def register(cls, helper_name):
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"""Decorator to register a handler function for a helper"""
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def decorator(func):
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cls._handlers[helper_name] = func
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return func
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return decorator
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@classmethod
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def get_handler(cls, helper_name):
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"""Get the handler function for a helper"""
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return cls._handlers.get(helper_name)
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def get_var_ptr_from_name(var_name, local_sym_tab):
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"""Get a pointer to a variable from the symbol table."""
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if local_sym_tab and var_name in local_sym_tab:
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return local_sym_tab[var_name][0]
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raise ValueError(f"Variable '{var_name}' not found in local symbol table")
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def create_int_constant_ptr(value, builder, int_width=64):
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"""Create a pointer to an integer constant."""
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# Default to 64-bit integer
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int_type = ir.IntType(int_width)
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ptr = builder.alloca(int_type)
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ptr.align = int_type.width // 8
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builder.store(ir.Constant(int_type, value), ptr)
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return ptr
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def get_key_ptr(call, builder, local_sym_tab):
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"""Extract key pointer from the call arguments."""
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if not call.args or len(call.args) != 1:
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raise ValueError("Map lookup expects exactly one argument, got "
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f"{len(call.args)}")
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key_arg = call.args[0]
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if isinstance(key_arg, ast.Name):
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key_ptr = get_var_ptr_from_name(key_arg.id, local_sym_tab)
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elif isinstance(key_arg, ast.Constant) and isinstance(key_arg.value, int):
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key_ptr = create_int_constant_ptr(key_arg.value, builder)
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else:
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raise NotImplementedError(
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"Only simple variable names are supported as keys in map lookup.")
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return key_ptr
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