30 Commits

Author SHA1 Message Date
8e3942d38c format chore 2025-10-08 14:31:37 +05:30
3abe07c5b2 add global symbol table populate function 2025-10-05 14:05:10 +05:30
01bd7604ed add global symbol table populate function 2025-10-05 14:04:25 +05:30
7ae84a0d5a add failing test 2025-10-05 00:55:38 +05:30
df3f00261a changer order of passes 2025-10-04 08:17:16 +05:30
ab610147a5 update globals test and todos. 2025-10-04 06:36:51 +05:30
7720fe9f9f format chore 2025-10-04 06:33:09 +05:30
7aeac86bd3 fix broken IR generation logic for globals 2025-10-04 06:32:25 +05:30
ab1c4223d5 fix broken IR generation logic for globals 2025-10-03 22:55:40 +05:30
c3a512d5cf add global support with broken generation function 2025-10-03 22:20:04 +05:30
4a60c42cd0 add global failing test
Signed-off-by: varun-r-mallya <varunrmallya@gmail.com>
2025-10-03 21:25:58 +05:30
b35134625b Merge pull request #19 from pythonbpf/fix-expr
Refactor expr_pass
2025-10-03 17:36:31 +05:30
c3db609a90 Revert to using Warning loglevel as default 2025-10-03 17:35:57 +05:30
cc626c38f7 Move binops1 to tests/passing 2025-10-03 17:13:02 +05:30
a8b3f4f86c Fix recursive binops, move failing binops to passing 2025-10-03 17:08:41 +05:30
d593969408 Refactor ugly if-elif chain in handle_binary_op 2025-10-03 14:04:38 +05:30
6d5895ebc2 More fixes to recursive dereferencer, add get_operand value 2025-10-03 13:46:52 +05:30
c9ee6e4f17 Fix recursive_dereferencer in binops 2025-10-03 13:35:15 +05:30
a622c53e0f Add deref 2025-10-03 02:00:01 +05:30
a4f1363aed Add _handle_attribute_expr 2025-10-03 01:50:59 +05:30
3a819dcaee Add _handle_constant_expr 2025-10-02 22:54:38 +05:30
729270b34b Use _handle_name_expr in eval_expr 2025-10-02 22:50:21 +05:30
44cbcccb6c Create _handle_name_expr 2025-10-02 22:43:54 +05:30
253944afd2 Merge pull request #18 from pythonbpf/fix-maps
Fix map calling convention
2025-10-02 22:12:01 +05:30
54993ce5c2 Merge branch 'master' into fix-maps 2025-10-02 22:11:38 +05:30
05083bd513 janitorial nitpicks 2025-10-02 22:10:28 +05:30
6e4c340780 Allow non-call convention for maps 2025-10-02 22:07:28 +05:30
9dbca410c2 Remove calls from map in sys_sync 2025-10-02 21:24:15 +05:30
62ca3b5ffe format errors 2025-10-02 19:07:49 +05:30
f263c35156 move debug cu generation to debug module 2025-10-02 19:05:58 +05:30
12 changed files with 486 additions and 165 deletions

View File

@ -21,17 +21,17 @@ def last() -> HashMap:
@section("tracepoint/syscalls/sys_enter_sync") @section("tracepoint/syscalls/sys_enter_sync")
def do_trace(ctx: c_void_p) -> c_int64: def do_trace(ctx: c_void_p) -> c_int64:
key = 0 key = 0
tsp = last().lookup(key) tsp = last.lookup(key)
if tsp: if tsp:
kt = ktime() kt = ktime()
delta = kt - tsp delta = kt - tsp
if delta < 1000000000: if delta < 1000000000:
time_ms = delta // 1000000 time_ms = delta // 1000000
print(f"sync called within last second, last {time_ms} ms ago") print(f"sync called within last second, last {time_ms} ms ago")
last().delete(key) last.delete(key)
else: else:
kt = ktime() kt = ktime()
last().update(key, kt) last.update(key, kt)
return c_int64(0) return c_int64(0)

View File

@ -8,68 +8,59 @@ logger: Logger = logging.getLogger(__name__)
def recursive_dereferencer(var, builder): def recursive_dereferencer(var, builder):
"""dereference until primitive type comes out""" """dereference until primitive type comes out"""
if var.type == ir.PointerType(ir.PointerType(ir.IntType(64))): # TODO: Not worrying about stack overflow for now
if isinstance(var.type, ir.PointerType):
a = builder.load(var) a = builder.load(var)
return recursive_dereferencer(a, builder) return recursive_dereferencer(a, builder)
elif var.type == ir.PointerType(ir.IntType(64)): elif isinstance(var.type, ir.IntType):
a = builder.load(var)
return recursive_dereferencer(a, builder)
elif var.type == ir.IntType(64):
return var return var
else: else:
raise TypeError(f"Unsupported type for dereferencing: {var.type}") raise TypeError(f"Unsupported type for dereferencing: {var.type}")
def handle_binary_op(rval, module, builder, var_name, local_sym_tab, map_sym_tab, func): def get_operand_value(operand, module, builder, local_sym_tab):
logger.info(f"module {module}") """Extract the value from an operand, handling variables and constants."""
left = rval.left if isinstance(operand, ast.Name):
right = rval.right if operand.id in local_sym_tab:
return recursive_dereferencer(local_sym_tab[operand.id].var, builder)
raise ValueError(f"Undefined variable: {operand.id}")
elif isinstance(operand, ast.Constant):
if isinstance(operand.value, int):
return ir.Constant(ir.IntType(64), operand.value)
raise TypeError(f"Unsupported constant type: {type(operand.value)}")
elif isinstance(operand, ast.BinOp):
return handle_binary_op_impl(operand, module, builder, local_sym_tab)
raise TypeError(f"Unsupported operand type: {type(operand)}")
def handle_binary_op_impl(rval, module, builder, local_sym_tab):
op = rval.op op = rval.op
left = get_operand_value(rval.left, module, builder, local_sym_tab)
# Handle left operand right = get_operand_value(rval.right, module, builder, local_sym_tab)
if isinstance(left, ast.Name):
if left.id in local_sym_tab:
left = recursive_dereferencer(local_sym_tab[left.id].var, builder)
else:
raise SyntaxError(f"Undefined variable: {left.id}")
elif isinstance(left, ast.Constant):
left = ir.Constant(ir.IntType(64), left.value)
else:
raise SyntaxError("Unsupported left operand type")
if isinstance(right, ast.Name):
if right.id in local_sym_tab:
right = recursive_dereferencer(local_sym_tab[right.id].var, builder)
else:
raise SyntaxError(f"Undefined variable: {right.id}")
elif isinstance(right, ast.Constant):
right = ir.Constant(ir.IntType(64), right.value)
else:
raise SyntaxError("Unsupported right operand type")
logger.info(f"left is {left}, right is {right}, op is {op}") logger.info(f"left is {left}, right is {right}, op is {op}")
if isinstance(op, ast.Add): # Map AST operation nodes to LLVM IR builder methods
builder.store(builder.add(left, right), local_sym_tab[var_name].var) op_map = {
elif isinstance(op, ast.Sub): ast.Add: builder.add,
builder.store(builder.sub(left, right), local_sym_tab[var_name].var) ast.Sub: builder.sub,
elif isinstance(op, ast.Mult): ast.Mult: builder.mul,
builder.store(builder.mul(left, right), local_sym_tab[var_name].var) ast.Div: builder.sdiv,
elif isinstance(op, ast.Div): ast.Mod: builder.srem,
builder.store(builder.sdiv(left, right), local_sym_tab[var_name].var) ast.LShift: builder.shl,
elif isinstance(op, ast.Mod): ast.RShift: builder.lshr,
builder.store(builder.srem(left, right), local_sym_tab[var_name].var) ast.BitOr: builder.or_,
elif isinstance(op, ast.LShift): ast.BitXor: builder.xor,
builder.store(builder.shl(left, right), local_sym_tab[var_name].var) ast.BitAnd: builder.and_,
elif isinstance(op, ast.RShift): ast.FloorDiv: builder.udiv,
builder.store(builder.lshr(left, right), local_sym_tab[var_name].var) }
elif isinstance(op, ast.BitOr):
builder.store(builder.or_(left, right), local_sym_tab[var_name].var) if type(op) in op_map:
elif isinstance(op, ast.BitXor): result = op_map[type(op)](left, right)
builder.store(builder.xor(left, right), local_sym_tab[var_name].var) return result
elif isinstance(op, ast.BitAnd):
builder.store(builder.and_(left, right), local_sym_tab[var_name].var)
elif isinstance(op, ast.FloorDiv):
builder.store(builder.udiv(left, right), local_sym_tab[var_name].var)
else: else:
raise SyntaxError("Unsupported binary operation") raise SyntaxError("Unsupported binary operation")
def handle_binary_op(rval, module, builder, var_name, local_sym_tab):
result = handle_binary_op_impl(rval, module, builder, local_sym_tab)
builder.store(result, local_sym_tab[var_name].var)

View File

@ -4,8 +4,12 @@ from .license_pass import license_processing
from .functions_pass import func_proc from .functions_pass import func_proc
from .maps import maps_proc from .maps import maps_proc
from .structs import structs_proc from .structs import structs_proc
from .globals_pass import globals_processing from .globals_pass import (
from .debuginfo import DW_LANG_C11, DwarfBehaviorEnum globals_list_creation,
globals_processing,
populate_global_symbol_table,
)
from .debuginfo import DW_LANG_C11, DwarfBehaviorEnum, DebugInfoGenerator
import os import os
import subprocess import subprocess
import inspect import inspect
@ -40,12 +44,15 @@ def processor(source_code, filename, module):
for func_node in bpf_chunks: for func_node in bpf_chunks:
logger.info(f"Found BPF function/struct: {func_node.name}") logger.info(f"Found BPF function/struct: {func_node.name}")
populate_global_symbol_table(tree, module)
license_processing(tree, module)
globals_processing(tree, module)
structs_sym_tab = structs_proc(tree, module, bpf_chunks) structs_sym_tab = structs_proc(tree, module, bpf_chunks)
map_sym_tab = maps_proc(tree, module, bpf_chunks) map_sym_tab = maps_proc(tree, module, bpf_chunks)
func_proc(tree, module, bpf_chunks, map_sym_tab, structs_sym_tab) func_proc(tree, module, bpf_chunks, map_sym_tab, structs_sym_tab)
license_processing(tree, module) globals_list_creation(tree, module)
globals_processing(tree, module)
def compile_to_ir(filename: str, output: str, loglevel=logging.WARNING): def compile_to_ir(filename: str, output: str, loglevel=logging.WARNING):
@ -60,33 +67,17 @@ def compile_to_ir(filename: str, output: str, loglevel=logging.WARNING):
module.triple = "bpf" module.triple = "bpf"
if not hasattr(module, "_debug_compile_unit"): if not hasattr(module, "_debug_compile_unit"):
module._file_metadata = module.add_debug_info( debug_generator = DebugInfoGenerator(module)
"DIFile", debug_generator.generate_file_metadata(filename, os.path.dirname(filename))
{ # type: ignore debug_generator.generate_debug_cu(
"filename": filename, DW_LANG_C11,
"directory": os.path.dirname(filename), f"PythonBPF {VERSION}",
}, True, # TODO: This is probably not true
# TODO: add a global field here that keeps track of all the globals. Works without it, but I think it might
# be required for kprobes.
True,
) )
module._debug_compile_unit = module.add_debug_info(
"DICompileUnit",
{ # type: ignore
"language": DW_LANG_C11,
"file": module._file_metadata, # type: ignore
"producer": f"PythonBPF {VERSION}",
"isOptimized": True, # TODO: This is probably not true
# TODO: add a global field here that keeps track of all the globals. Works without it, but I think it might
# be required for kprobes.
"runtimeVersion": 0,
"emissionKind": 1,
"splitDebugInlining": False,
"nameTableKind": 0,
},
is_distinct=True,
)
module.add_named_metadata("llvm.dbg.cu", module._debug_compile_unit) # type: ignore
processor(source, filename, module) processor(source, filename, module)
wchar_size = module.add_metadata( wchar_size = module.add_metadata(

View File

@ -12,6 +12,34 @@ class DebugInfoGenerator:
self.module = module self.module = module
self._type_cache = {} # Cache for common debug types self._type_cache = {} # Cache for common debug types
def generate_file_metadata(self, filename, dirname):
self.module._file_metadata = self.module.add_debug_info(
"DIFile",
{ # type: ignore
"filename": filename,
"directory": dirname,
},
)
def generate_debug_cu(
self, language, producer: str, is_optimized: bool, is_distinct: bool
):
self.module._debug_compile_unit = self.module.add_debug_info(
"DICompileUnit",
{ # type: ignore
"language": language,
"file": self.module._file_metadata, # type: ignore
"producer": producer,
"isOptimized": is_optimized,
"runtimeVersion": 0,
"emissionKind": 1,
"splitDebugInlining": False,
"nameTableKind": 0,
},
is_distinct=is_distinct,
)
self.module.add_named_metadata("llvm.dbg.cu", self.module._debug_compile_unit) # type: ignore
def get_basic_type(self, name: str, size: int, encoding: int) -> Any: def get_basic_type(self, name: str, size: int, encoding: int) -> Any:
"""Get or create a basic type with caching""" """Get or create a basic type with caching"""
key = (name, size, encoding) key = (name, size, encoding)

View File

@ -2,10 +2,92 @@ import ast
from llvmlite import ir from llvmlite import ir
from logging import Logger from logging import Logger
import logging import logging
from typing import Dict
logger: Logger = logging.getLogger(__name__) logger: Logger = logging.getLogger(__name__)
def _handle_name_expr(expr: ast.Name, local_sym_tab: Dict, builder: ir.IRBuilder):
"""Handle ast.Name expressions."""
if expr.id in local_sym_tab:
var = local_sym_tab[expr.id].var
val = builder.load(var)
return val, local_sym_tab[expr.id].ir_type
else:
logger.info(f"Undefined variable {expr.id}")
return None
def _handle_constant_expr(expr: ast.Constant):
"""Handle ast.Constant expressions."""
if isinstance(expr.value, int):
return ir.Constant(ir.IntType(64), expr.value), ir.IntType(64)
elif isinstance(expr.value, bool):
return ir.Constant(ir.IntType(1), int(expr.value)), ir.IntType(1)
else:
logger.info("Unsupported constant type")
return None
def _handle_attribute_expr(
expr: ast.Attribute,
local_sym_tab: Dict,
structs_sym_tab: Dict,
builder: ir.IRBuilder,
):
"""Handle ast.Attribute expressions for struct field access."""
if isinstance(expr.value, ast.Name):
var_name = expr.value.id
attr_name = expr.attr
if var_name in local_sym_tab:
var_ptr, var_type, var_metadata = local_sym_tab[var_name]
logger.info(f"Loading attribute {attr_name} from variable {var_name}")
logger.info(f"Variable type: {var_type}, Variable ptr: {var_ptr}")
metadata = structs_sym_tab[var_metadata]
if attr_name in metadata.fields:
gep = metadata.gep(builder, var_ptr, attr_name)
val = builder.load(gep)
field_type = metadata.field_type(attr_name)
return val, field_type
return None
def _handle_deref_call(expr: ast.Call, local_sym_tab: Dict, builder: ir.IRBuilder):
"""Handle deref function calls."""
logger.info(f"Handling deref {ast.dump(expr)}")
if len(expr.args) != 1:
logger.info("deref takes exactly one argument")
return None
arg = expr.args[0]
if (
isinstance(arg, ast.Call)
and isinstance(arg.func, ast.Name)
and arg.func.id == "deref"
):
logger.info("Multiple deref not supported")
return None
if isinstance(arg, ast.Name):
if arg.id in local_sym_tab:
arg_ptr = local_sym_tab[arg.id].var
else:
logger.info(f"Undefined variable {arg.id}")
return None
else:
logger.info("Unsupported argument type for deref")
return None
if arg_ptr is None:
logger.info("Failed to evaluate deref argument")
return None
# Load the value from pointer
val = builder.load(arg_ptr)
return val, local_sym_tab[arg.id].ir_type
def eval_expr( def eval_expr(
func, func,
module, module,
@ -17,64 +99,28 @@ def eval_expr(
): ):
logger.info(f"Evaluating expression: {ast.dump(expr)}") logger.info(f"Evaluating expression: {ast.dump(expr)}")
if isinstance(expr, ast.Name): if isinstance(expr, ast.Name):
if expr.id in local_sym_tab: return _handle_name_expr(expr, local_sym_tab, builder)
var = local_sym_tab[expr.id].var
val = builder.load(var)
return val, local_sym_tab[expr.id].ir_type # return value and type
else:
logger.info(f"Undefined variable {expr.id}")
return None
elif isinstance(expr, ast.Constant): elif isinstance(expr, ast.Constant):
if isinstance(expr.value, int): return _handle_constant_expr(expr)
return ir.Constant(ir.IntType(64), expr.value), ir.IntType(64)
elif isinstance(expr.value, bool):
return ir.Constant(ir.IntType(1), int(expr.value)), ir.IntType(1)
else:
logger.info("Unsupported constant type")
return None
elif isinstance(expr, ast.Call): elif isinstance(expr, ast.Call):
if isinstance(expr.func, ast.Name) and expr.func.id == "deref":
return _handle_deref_call(expr, local_sym_tab, builder)
# delayed import to avoid circular dependency # delayed import to avoid circular dependency
from pythonbpf.helper import HelperHandlerRegistry, handle_helper_call from pythonbpf.helper import HelperHandlerRegistry, handle_helper_call
if isinstance(expr.func, ast.Name): if isinstance(expr.func, ast.Name) and HelperHandlerRegistry.has_handler(
# check deref expr.func.id
if expr.func.id == "deref": ):
logger.info(f"Handling deref {ast.dump(expr)}") return handle_helper_call(
if len(expr.args) != 1: expr,
logger.info("deref takes exactly one argument") module,
return None builder,
arg = expr.args[0] func,
if ( local_sym_tab,
isinstance(arg, ast.Call) map_sym_tab,
and isinstance(arg.func, ast.Name) structs_sym_tab,
and arg.func.id == "deref" )
):
logger.info("Multiple deref not supported")
return None
if isinstance(arg, ast.Name):
if arg.id in local_sym_tab:
arg = local_sym_tab[arg.id].var
else:
logger.info(f"Undefined variable {arg.id}")
return None
if arg is None:
logger.info("Failed to evaluate deref argument")
return None
# Since we are handling only name case, directly take type from sym tab
val = builder.load(arg)
return val, local_sym_tab[expr.args[0].id].ir_type
# check for helpers
if HelperHandlerRegistry.has_handler(expr.func.id):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(expr.func, ast.Attribute): elif isinstance(expr.func, ast.Attribute):
logger.info(f"Handling method call: {ast.dump(expr.func)}") logger.info(f"Handling method call: {ast.dump(expr.func)}")
if isinstance(expr.func.value, ast.Call) and isinstance( if isinstance(expr.func.value, ast.Call) and isinstance(
@ -106,19 +152,7 @@ def eval_expr(
structs_sym_tab, structs_sym_tab,
) )
elif isinstance(expr, ast.Attribute): elif isinstance(expr, ast.Attribute):
if isinstance(expr.value, ast.Name): return _handle_attribute_expr(expr, local_sym_tab, structs_sym_tab, builder)
var_name = expr.value.id
attr_name = expr.attr
if var_name in local_sym_tab:
var_ptr, var_type, var_metadata = local_sym_tab[var_name]
logger.info(f"Loading attribute {attr_name} from variable {var_name}")
logger.info(f"Variable type: {var_type}, Variable ptr: {var_ptr}")
metadata = structs_sym_tab[var_metadata]
if attr_name in metadata.fields:
gep = metadata.gep(builder, var_ptr, attr_name)
val = builder.load(gep)
field_type = metadata.field_type(attr_name)
return val, field_type
logger.info("Unsupported expression evaluation") logger.info("Unsupported expression evaluation")
return None return None

View File

@ -192,8 +192,23 @@ def handle_assign(
elif isinstance(rval.func, ast.Attribute): elif isinstance(rval.func, ast.Attribute):
logger.info(f"Assignment call attribute: {ast.dump(rval.func)}") logger.info(f"Assignment call attribute: {ast.dump(rval.func)}")
if isinstance(rval.func.value, ast.Name): if isinstance(rval.func.value, ast.Name):
# TODO: probably a struct access if rval.func.value.id in map_sym_tab:
logger.info(f"TODO STRUCT ACCESS {ast.dump(rval)}") map_name = rval.func.value.id
method_name = rval.func.attr
if HelperHandlerRegistry.has_handler(method_name):
val = handle_helper_call(
rval,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
builder.store(val[0], local_sym_tab[var_name].var)
else:
# TODO: probably a struct access
logger.info(f"TODO STRUCT ACCESS {ast.dump(rval)}")
elif isinstance(rval.func.value, ast.Call) and isinstance( elif isinstance(rval.func.value, ast.Call) and isinstance(
rval.func.value.func, ast.Name rval.func.value.func, ast.Name
): ):
@ -218,9 +233,7 @@ def handle_assign(
else: else:
logger.info("Unsupported assignment call function type") logger.info("Unsupported assignment call function type")
elif isinstance(rval, ast.BinOp): elif isinstance(rval, ast.BinOp):
handle_binary_op( handle_binary_op(rval, module, builder, var_name, local_sym_tab)
rval, module, builder, var_name, local_sym_tab, map_sym_tab, func
)
else: else:
logger.info("Unsupported assignment value type") logger.info("Unsupported assignment value type")

View File

@ -1,8 +1,121 @@
from llvmlite import ir from llvmlite import ir
import ast import ast
from logging import Logger
import logging
from .type_deducer import ctypes_to_ir
def emit_globals(module: ir.Module, names: list[str]): logger: Logger = logging.getLogger(__name__)
# TODO: this is going to be a huge fuck of a headache in the future.
global_sym_tab = []
def populate_global_symbol_table(tree, module: ir.Module):
for node in tree.body:
if isinstance(node, ast.FunctionDef):
for dec in node.decorator_list:
if (
isinstance(dec, ast.Call)
and isinstance(dec.func, ast.Name)
and dec.func.id == "section"
and len(dec.args) == 1
and isinstance(dec.args[0], ast.Constant)
and isinstance(dec.args[0].value, str)
):
global_sym_tab.append(node)
elif isinstance(dec, ast.Name) and dec.id == "bpfglobal":
global_sym_tab.append(node)
elif isinstance(dec, ast.Name) and dec.id == "map":
global_sym_tab.append(node)
return False
def emit_global(module: ir.Module, node, name):
logger.info(f"global identifier {name} processing")
# deduce LLVM type from the annotated return
if not isinstance(node.returns, ast.Name):
raise ValueError(f"Unsupported return annotation {ast.dump(node.returns)}")
ty = ctypes_to_ir(node.returns.id)
# extract the return expression
# TODO: turn this return extractor into a generic function I can use everywhere.
ret_stmt = node.body[0]
if not isinstance(ret_stmt, ast.Return) or ret_stmt.value is None:
raise ValueError(f"Global '{name}' has no valid return")
init_val = ret_stmt.value
# simple constant like "return 0"
if isinstance(init_val, ast.Constant):
llvm_init = ir.Constant(ty, init_val.value)
# variable reference like "return SOME_CONST"
elif isinstance(init_val, ast.Name):
# need symbol resolution here, stub as 0 for now
raise ValueError(f"Name reference {init_val.id} not yet supported")
# constructor call like "return c_int64(0)" or dataclass(...)
elif isinstance(init_val, ast.Call):
if len(init_val.args) >= 1 and isinstance(init_val.args[0], ast.Constant):
llvm_init = ir.Constant(ty, init_val.args[0].value)
else:
logger.info("Defaulting to zero as no constant argument found")
llvm_init = ir.Constant(ty, 0)
else:
raise ValueError(f"Unsupported return expr {ast.dump(init_val)}")
gvar = ir.GlobalVariable(module, ty, name=name)
gvar.initializer = llvm_init
gvar.align = 8
gvar.linkage = "dso_local"
gvar.global_constant = False
return gvar
def globals_processing(tree, module):
"""Process stuff decorated with @bpf and @bpfglobal except license and return the section name"""
globals_sym_tab = []
for node in tree.body:
# Skip non-assignment and non-function nodes
if not (isinstance(node, ast.FunctionDef)):
continue
# Get the name based on node type
if isinstance(node, ast.FunctionDef):
name = node.name
else:
continue
# Check for duplicate names
if name in globals_sym_tab:
raise SyntaxError(f"ERROR: Global name '{name}' previously defined")
else:
globals_sym_tab.append(name)
if isinstance(node, ast.FunctionDef) and node.name != "LICENSE":
decorators = [
dec.id for dec in node.decorator_list if isinstance(dec, ast.Name)
]
if "bpf" in decorators and "bpfglobal" in decorators:
if (
len(node.body) == 1
and isinstance(node.body[0], ast.Return)
and node.body[0].value is not None
and isinstance(
node.body[0].value, (ast.Constant, ast.Name, ast.Call)
)
):
emit_global(module, node, name)
else:
raise SyntaxError(f"ERROR: Invalid syntax for {name} global")
return None
def emit_llvm_compiler_used(module: ir.Module, names: list[str]):
""" """
Emit the @llvm.compiler.used global given a list of function/global names. Emit the @llvm.compiler.used global given a list of function/global names.
""" """
@ -24,7 +137,7 @@ def emit_globals(module: ir.Module, names: list[str]):
gv.section = "llvm.metadata" gv.section = "llvm.metadata"
def globals_processing(tree, module: ir.Module): def globals_list_creation(tree, module: ir.Module):
collected = ["LICENSE"] collected = ["LICENSE"]
for node in tree.body: for node in tree.body:
@ -40,10 +153,11 @@ def globals_processing(tree, module: ir.Module):
): ):
collected.append(node.name) collected.append(node.name)
elif isinstance(dec, ast.Name) and dec.id == "bpfglobal": # NOTE: all globals other than
collected.append(node.name) # elif isinstance(dec, ast.Name) and dec.id == "bpfglobal":
# collected.append(node.name)
elif isinstance(dec, ast.Name) and dec.id == "map": elif isinstance(dec, ast.Name) and dec.id == "map":
collected.append(node.name) collected.append(node.name)
emit_globals(module, collected) emit_llvm_compiler_used(module, collected)

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@ -0,0 +1,27 @@
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <linux/types.h>
struct test_struct {
__u64 a;
__u64 b;
};
struct test_struct w = {};
volatile __u64 prev_time = 0;
SEC("tracepoint/syscalls/sys_enter_execve")
int trace_execve(void *ctx)
{
bpf_printk("previous %ul now %ul", w.b, w.a);
__u64 ts = bpf_ktime_get_ns();
bpf_printk("prev %ul now %ul", prev_time, ts);
w.a = ts;
w.b = prev_time;
prev_time = ts;
return 0;
}
char LICENSE[] SEC("license") = "GPL";

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@ -0,0 +1,101 @@
import logging
from pythonbpf import compile, bpf, section, bpfglobal, compile_to_ir
from ctypes import c_void_p, c_int64, c_int32
@bpf
@bpfglobal
def somevalue() -> c_int32:
return c_int32(42)
@bpf
@bpfglobal
def somevalue2() -> c_int64:
return c_int64(69)
@bpf
@bpfglobal
def somevalue1() -> c_int32:
return c_int32(42)
# --- Passing examples ---
# Simple constant return
@bpf
@bpfglobal
def g1() -> c_int64:
return c_int64(42)
# Constructor with one constant argument
@bpf
@bpfglobal
def g2() -> c_int64:
return c_int64(69)
# --- Failing examples ---
# No return annotation
# @bpf
# @bpfglobal
# def g3():
# return 42
# Return annotation is complex
# @bpf
# @bpfglobal
# def g4() -> List[int]:
# return []
# # Return is missing
# @bpf
# @bpfglobal
# def g5() -> c_int64:
# pass
# # Return is a variable reference
# #TODO: maybe fix this sometime later. It defaults to 0
# CONST = 5
# @bpf
# @bpfglobal
# def g6() -> c_int64:
# return c_int64(CONST)
# Constructor with multiple args
#TODO: this is not working. should it work ?
@bpf
@bpfglobal
def g7() -> c_int64:
return c_int64(1)
# Dataclass call
#TODO: fails with dataclass
# @dataclass
# class Point:
# x: c_int64
# y: c_int64
# @bpf
# @bpfglobal
# def g8() -> Point:
# return Point(1, 2)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def sometag(ctx: c_void_p) -> c_int64:
print("test")
global somevalue
somevalue = 2
print(f"{somevalue}")
return c_int64(1)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile_to_ir("globals.py", "globals.ll", loglevel=logging.INFO)
compile()

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@ -0,0 +1,21 @@
import logging
from pythonbpf import compile, bpf, section, bpfglobal, compile_to_ir
from ctypes import c_void_p, c_int64
# This should not pass as somevalue is not declared at all.
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def sometag(ctx: c_void_p) -> c_int64:
print("test")
print(f"{somevalue}") # noqa: F821
return c_int64(1)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile_to_ir("globals.py", "globals.ll", loglevel=logging.INFO)
compile()

View File

@ -3,9 +3,9 @@ from ctypes import c_void_p, c_int64
@bpf @bpf
@section("sometag1") @section("tracepoint/syscalls/sys_enter_sync")
def sometag(ctx: c_void_p) -> c_int64: def sometag(ctx: c_void_p) -> c_int64:
a = 1 + 2 + 1 a = 1 + 2 + 1 + 12 + 13
print(f"{a}") print(f"{a}")
return c_int64(0) return c_int64(0)

View File

@ -3,11 +3,12 @@ from ctypes import c_void_p, c_int64
@bpf @bpf
@section("sometag1") @section("tracepoint/syscalls/sys_enter_sync")
def sometag(ctx: c_void_p) -> c_int64: def sometag(ctx: c_void_p) -> c_int64:
b = 1 + 2 b = 1 + 2
a = 1 + b a = 1 + b
return c_int64(a) print(f"{a}")
return c_int64(0)
@bpf @bpf