Merge pull request #64 from pythonbpf/all_helpers

Add support for all eBPF helpers

Author: r41k0u

pythonbpf/allocation_pass.py

@@ -177,17 +177,33 @@ def _allocate_for_binop(builder, var_name, local_sym_tab):
     logger.info(f"Pre-allocated {var_name} for binop result")
 
 
+def _get_type_name(ir_type):
+    """Get a string representation of an IR type."""
+    if isinstance(ir_type, ir.IntType):
+        return f"i{ir_type.width}"
+    elif isinstance(ir_type, ir.PointerType):
+        return "ptr"
+    elif isinstance(ir_type, ir.ArrayType):
+        return f"[{ir_type.count}x{_get_type_name(ir_type.element)}]"
+    else:
+        return str(ir_type).replace(" ", "")
+
+
 def allocate_temp_pool(builder, max_temps, local_sym_tab):
     """Allocate the temporary scratch space pool for helper arguments."""
-    if max_temps == 0:
+    if not max_temps:
+        logger.info("No temp pool allocation needed")
         return
 
-    logger.info(f"Allocating temp pool of {max_temps} variables")
-    for i in range(max_temps):
-        temp_name = f"__helper_temp_{i}"
-        temp_var = builder.alloca(ir.IntType(64), name=temp_name)
-        temp_var.align = 8
-        local_sym_tab[temp_name] = LocalSymbol(temp_var, ir.IntType(64))
+    for tmp_type, cnt in max_temps.items():
+        type_name = _get_type_name(tmp_type)
+        logger.info(f"Allocating temp pool of {cnt} variables of type {type_name}")
+        for i in range(cnt):
+            temp_name = f"__helper_temp_{type_name}_{i}"
+            temp_var = builder.alloca(tmp_type, name=temp_name)
+            temp_var.align = _get_alignment(tmp_type)
+            local_sym_tab[temp_name] = LocalSymbol(temp_var, tmp_type)
+            logger.debug(f"Allocated temp variable: {temp_name}")
 
 
 def _allocate_for_name(builder, var_name, rval, local_sym_tab):

pythonbpf/functions/functions_pass.py

@@ -39,7 +39,7 @@
 def count_temps_in_call(call_node, local_sym_tab):
     """Count the number of temporary variables needed for a function call."""
 
-    count = 0
+    count = {}
     is_helper = False
 
     # NOTE: We exclude print calls for now
@@ -49,21 +49,28 @@ def count_temps_in_call(call_node, local_sym_tab):
             and call_node.func.id != "print"
         ):
             is_helper = True
+            func_name = call_node.func.id
     elif isinstance(call_node.func, ast.Attribute):
         if HelperHandlerRegistry.has_handler(call_node.func.attr):
             is_helper = True
+            func_name = call_node.func.attr
 
     if not is_helper:
-        return 0
+        return {}  # No temps needed
 
-    for arg in call_node.args:
+    for arg_idx in range(len(call_node.args)):
         # NOTE: Count all non-name arguments
         # For struct fields, if it is being passed as an argument,
         # The struct object should already exist in the local_sym_tab
-        if not isinstance(arg, ast.Name) and not (
+        arg = call_node.args[arg_idx]
+        if isinstance(arg, ast.Name) or (
             isinstance(arg, ast.Attribute) and arg.value.id in local_sym_tab
         ):
-            count += 1
+            continue
+        param_type = HelperHandlerRegistry.get_param_type(func_name, arg_idx)
+        if isinstance(param_type, ir.PointerType):
+            pointee_type = param_type.pointee
+            count[pointee_type] = count.get(pointee_type, 0) + 1
 
     return count
 
@@ -99,11 +106,15 @@ def handle_if_allocation(
 def allocate_mem(
     module, builder, body, func, ret_type, map_sym_tab, local_sym_tab, structs_sym_tab
 ):
-    max_temps_needed = 0
+    max_temps_needed = {}
+
+    def merge_type_counts(count_dict):
+        nonlocal max_temps_needed
+        for typ, cnt in count_dict.items():
+            max_temps_needed[typ] = max(max_temps_needed.get(typ, 0), cnt)
 
     def update_max_temps_for_stmt(stmt):
         nonlocal max_temps_needed
-        temps_needed = 0
 
         if isinstance(stmt, ast.If):
             for s in stmt.body:
@@ -112,10 +123,13 @@ def update_max_temps_for_stmt(stmt):
                 update_max_temps_for_stmt(s)
             return
 
+        stmt_temps = {}
         for node in ast.walk(stmt):
             if isinstance(node, ast.Call):
-                temps_needed += count_temps_in_call(node, local_sym_tab)
-        max_temps_needed = max(max_temps_needed, temps_needed)
+                call_temps = count_temps_in_call(node, local_sym_tab)
+                for typ, cnt in call_temps.items():
+                    stmt_temps[typ] = stmt_temps.get(typ, 0) + cnt
+        merge_type_counts(stmt_temps)
 
     for stmt in body:
         update_max_temps_for_stmt(stmt)

pythonbpf/helper/__init__.py

@@ -1,7 +1,20 @@
 from .helper_registry import HelperHandlerRegistry
 from .helper_utils import reset_scratch_pool
 from .bpf_helper_handler import handle_helper_call, emit_probe_read_kernel_str_call
-from .helpers import ktime, pid, deref, comm, probe_read_str, XDP_DROP, XDP_PASS
+from .helpers import (
+    ktime,
+    pid,
+    deref,
+    comm,
+    probe_read_str,
+    random,
+    probe_read,
+    smp_processor_id,
+    uid,
+    skb_store_bytes,
+    XDP_DROP,
+    XDP_PASS,
+)
 
 
 # Register the helper handler with expr module
@@ -65,6 +78,11 @@ def helper_call_handler(
     "deref",
     "comm",
     "probe_read_str",
+    "random",
+    "probe_read",
+    "smp_processor_id",
+    "uid",
+    "skb_store_bytes",
     "XDP_DROP",
     "XDP_PASS",
 ]