Handle nested map lookup helper args

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: r41k0u

pythonbpf/helper/bpf_helper_handler.py

@@ -113,7 +113,12 @@ def bpf_map_lookup_elem_emitter(
             f"Map lookup expects exactly one argument (key), got {len(call.args)}"
         )
     key_ptr = get_or_create_ptr_from_arg(
-        func, compilation_context, call.args[0], builder, local_sym_tab
+        func,
+        compilation_context,
+        call.args[0],
+        builder,
+        local_sym_tab,
+        expected_type=ir.IntType(64),
     )
     map_void_ptr = builder.bitcast(map_ptr, ir.PointerType())
 
@@ -215,10 +220,20 @@ def bpf_map_update_elem_emitter(
     flags_arg = call.args[2] if len(call.args) > 2 else None
 
     key_ptr = get_or_create_ptr_from_arg(
-        func, compilation_context, key_arg, builder, local_sym_tab
+        func,
+        compilation_context,
+        key_arg,
+        builder,
+        local_sym_tab,
+        expected_type=ir.IntType(64),
     )
     value_ptr = get_or_create_ptr_from_arg(
-        func, compilation_context, value_arg, builder, local_sym_tab
+        func,
+        compilation_context,
+        value_arg,
+        builder,
+        local_sym_tab,
+        expected_type=ir.IntType(64),
     )
     flags_val = get_flags_val(flags_arg, builder, local_sym_tab)
 

pythonbpf/helper/helper_utils.py

@@ -6,6 +6,8 @@
     eval_expr,
     access_struct_field,
 )
+from pythonbpf.expr.ir_ops import deref_to_depth
+from pythonbpf.expr.type_normalization import get_base_type_and_depth
 
 logger = logging.getLogger(__name__)
 
@@ -104,6 +106,12 @@ def get_or_create_ptr_from_arg(
         if val is None:
             raise ValueError("Failed to evaluate expression for helper arg.")
 
+        if expected_type and isinstance(val.type, ir.PointerType):
+            _, val_depth = get_base_type_and_depth(val.type)
+            _, expected_depth = get_base_type_and_depth(expected_type)
+            if val_depth > expected_depth:
+                val = deref_to_depth(func, builder, val, val_depth - expected_depth)
+
         ptr, temp_name = compilation_context.scratch_pool.get_next_temp(
             local_sym_tab, expected_type
         )