mirror of
https://github.com/varun-r-mallya/Python-BPF.git
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varun-r-mallya
8ee5d03c5d
WARNING: OLD STYLE IMPORTS DO NOT WORK The old style of importing the full module and using pb.* prefixes has been replaced with direct imports of the needed names. This makes the code more explicit about what is being used and removes the unnecessary pb prefix.
114 lines
4.1 KiB
Python
114 lines
4.1 KiB
Python
import ast
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from llvmlite import ir
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from .license_pass import license_processing
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from .functions_pass import func_proc
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from .maps_pass import maps_proc
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from .globals_pass import globals_processing
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import os
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import subprocess
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import inspect
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from pathlib import Path
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def find_bpf_chunks(tree):
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"""Find all functions decorated with @bpf in the AST."""
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bpf_functions = []
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for node in ast.walk(tree):
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if isinstance(node, ast.FunctionDef):
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for decorator in node.decorator_list:
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if isinstance(decorator, ast.Name) and decorator.id == "bpf":
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bpf_functions.append(node)
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break
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return bpf_functions
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def processor(source_code, filename, module):
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tree = ast.parse(source_code, filename)
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print(ast.dump(tree, indent=4))
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bpf_chunks = find_bpf_chunks(tree)
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for func_node in bpf_chunks:
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print(f"Found BPF function: {func_node.name}")
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map_sym_tab = maps_proc(tree, module, bpf_chunks)
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func_proc(tree, module, bpf_chunks, map_sym_tab)
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license_processing(tree, module)
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globals_processing(tree, module)
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def compile_to_ir(filename: str, output: str):
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with open(filename) as f:
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source = f.read()
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module = ir.Module(name=filename)
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module.data_layout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128"
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module.triple = "bpf"
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if not hasattr(module, '_debug_compile_unit'):
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module._file_metadata = module.add_debug_info("DIFile", { # type: ignore
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"filename": filename,
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"directory": os.path.dirname(filename)
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})
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module._debug_compile_unit = module.add_debug_info("DICompileUnit", { # type: ignore
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"language": 29, # DW_LANG_C11
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"file": module._file_metadata, # type: ignore
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"producer": "PythonBPF DSL Compiler",
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"isOptimized": True,
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"runtimeVersion": 0,
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"emissionKind": 1,
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"splitDebugInlining": False,
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"nameTableKind": 0
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}, is_distinct=True)
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module.add_named_metadata("llvm.dbg.cu", module._debug_compile_unit) # type: ignore
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processor(source, filename, module)
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wchar_size = module.add_metadata([ir.Constant(ir.IntType(32), 1),
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"wchar_size",
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ir.Constant(ir.IntType(32), 4)])
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frame_pointer = module.add_metadata([ir.Constant(ir.IntType(32), 7),
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"frame-pointer",
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ir.Constant(ir.IntType(32), 2)])
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# Add Debug Info Version (3 = DWARF v3, which LLVM expects)
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debug_info_version = module.add_metadata([ir.Constant(ir.IntType(32), 2),
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"Debug Info Version",
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ir.Constant(ir.IntType(32), 3)])
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# Add explicit DWARF version (4 is common, works with LLVM BPF backend)
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dwarf_version = module.add_metadata([ir.Constant(ir.IntType(32), 2),
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"Dwarf Version",
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ir.Constant(ir.IntType(32), 4)])
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module.add_named_metadata("llvm.module.flags", wchar_size)
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module.add_named_metadata("llvm.module.flags", frame_pointer)
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module.add_named_metadata("llvm.module.flags", debug_info_version)
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module.add_named_metadata("llvm.module.flags", dwarf_version)
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module.add_named_metadata("llvm.ident", ["llvmlite PythonBPF v0.0.1"])
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with open(output, "w") as f:
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f.write(f"source_filename = \"{filename}\"\n")
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f.write(str(module))
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f.write("\n")
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return output
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def compile():
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# Look one level up the stack to the caller of this function
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caller_frame = inspect.stack()[1]
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caller_file = Path(caller_frame.filename).resolve()
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ll_file = Path("/tmp") / caller_file.with_suffix(".ll").name
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o_file = caller_file.with_suffix(".o")
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compile_to_ir(str(caller_file), str(ll_file))
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subprocess.run([
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"llc", "-march=bpf", "-filetype=obj", "-O2",
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str(ll_file), "-o", str(o_file)
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], check=True)
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print(f"Object written to {o_file}")
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