Add sync_count BCC example to use tuple-like assignment

BCC-Examples/sync_count.py

@@ -14,10 +14,8 @@ def last() -> HashMap:
 @bpf
 @section("tracepoint/syscalls/sys_enter_sync")
 def do_trace(ctx: c_void_p) -> c_int64:
-    ts_key = 0
-    cnt_key = 1
-    tsp = last.lookup(ts_key)
-    cntp = last.lookup(cnt_key)
+    ts_key, cnt_key = 0, 1
+    tsp, cntp = last.lookup(ts_key), last.lookup(cnt_key)
     if not cntp:
         last.update(cnt_key, 0)
         cntp = last.lookup(cnt_key)

pythonbpf/allocation_pass.py

@@ -22,44 +22,60 @@ class LocalSymbol:
         yield self.metadata
 
 
+def create_targets_and_rvals(stmt):
+    """Create lists of targets and right-hand values from an assignment statement."""
+    if isinstance(stmt.targets[0], ast.Tuple):
+        if not isinstance(stmt.value, ast.Tuple):
+            logger.warning("Mismatched multi-target assignment, skipping allocation")
+            return
+        targets, rvals = stmt.targets[0].elts, stmt.value.elts
+        if len(targets) != len(rvals):
+            logger.warning("length of LHS != length of RHS, skipping allocation")
+            return
+        return targets, rvals
+    return stmt.targets, [stmt.value]
+
+
 def handle_assign_allocation(builder, stmt, local_sym_tab, structs_sym_tab):
     """Handle memory allocation for assignment statements."""
 
-    # Validate assignment
-    if len(stmt.targets) != 1:
-        logger.warning("Multi-target assignment not supported, skipping allocation")
-        return
+    logger.info(f"Handling assignment for allocation: {ast.dump(stmt)}")
 
-    target = stmt.targets[0]
+    # NOTE: Support multi-target assignments (e.g.: a, b = 1, 2)
+    targets, rvals = create_targets_and_rvals(stmt)
 
-    # Skip non-name targets (e.g., struct field assignments)
-    if isinstance(target, ast.Attribute):
-        logger.debug(f"Struct field assignment to {target.attr}, no allocation needed")
-        return
+    for target, rval in zip(targets, rvals):
+        # Skip non-name targets (e.g., struct field assignments)
+        if isinstance(target, ast.Attribute):
+            logger.debug(
+                f"Struct field assignment to {target.attr}, no allocation needed"
+            )
+            continue
 
-    if not isinstance(target, ast.Name):
-        logger.warning(f"Unsupported assignment target type: {type(target).__name__}")
-        return
+        if not isinstance(target, ast.Name):
+            logger.warning(
+                f"Unsupported assignment target type: {type(target).__name__}"
+            )
+            continue
 
-    var_name = target.id
-    rval = stmt.value
+        var_name = target.id
 
-    # Skip if already allocated
-    if var_name in local_sym_tab:
-        logger.debug(f"Variable {var_name} already allocated, skipping")
-        return
+        # Skip if already allocated
+        if var_name in local_sym_tab:
+            logger.debug(f"Variable {var_name} already allocated, skipping")
+            continue
 
-    # Determine type and allocate based on rval
-    if isinstance(rval, ast.Call):
-        _allocate_for_call(builder, var_name, rval, local_sym_tab, structs_sym_tab)
-    elif isinstance(rval, ast.Constant):
-        _allocate_for_constant(builder, var_name, rval, local_sym_tab)
-    elif isinstance(rval, ast.BinOp):
-        _allocate_for_binop(builder, var_name, local_sym_tab)
-    else:
-        logger.warning(
-            f"Unsupported assignment value type for {var_name}: {type(rval).__name__}"
-        )
+        # Determine type and allocate based on rval
+        if isinstance(rval, ast.Call):
+            _allocate_for_call(builder, var_name, rval, local_sym_tab, structs_sym_tab)
+        elif isinstance(rval, ast.Constant):
+            _allocate_for_constant(builder, var_name, rval, local_sym_tab)
+        elif isinstance(rval, ast.BinOp):
+            _allocate_for_binop(builder, var_name, local_sym_tab)
+        else:
+            logger.warning(
+                f"Unsupported assignment value type for {var_name}: {type(rval).__name__}"
+            )
 
 
 def _allocate_for_call(builder, var_name, rval, local_sym_tab, structs_sym_tab):

pythonbpf/functions/functions_pass.py

@@ -12,7 +12,11 @@ from pythonbpf.assign_pass import (
     handle_variable_assignment,
     handle_struct_field_assignment,
 )
-from pythonbpf.allocation_pass import handle_assign_allocation, allocate_temp_pool
+from pythonbpf.allocation_pass import (
+    handle_assign_allocation,
+    allocate_temp_pool,
+    create_targets_and_rvals,
+)
 
 from .return_utils import handle_none_return, handle_xdp_return, is_xdp_name
 from .function_metadata import get_probe_string, is_global_function, infer_return_type
@@ -140,48 +144,43 @@ def handle_assign(
 ):
     """Handle assignment statements in the function body."""
 
-    # TODO: Support this later
-    # GH #37
-    if len(stmt.targets) != 1:
-        logger.error("Multi-target assignment is not supported for now")
-        return
+    # NOTE: Support multi-target assignments (e.g.: a, b = 1, 2)
+    targets, rvals = create_targets_and_rvals(stmt)
 
-    target = stmt.targets[0]
-    rval = stmt.value
+    for target, rval in zip(targets, rvals):
+        if isinstance(target, ast.Name):
+            # NOTE: Simple variable assignment case: x = 5
+            var_name = target.id
+            result = handle_variable_assignment(
+                func,
+                module,
+                builder,
+                var_name,
+                rval,
+                local_sym_tab,
+                map_sym_tab,
+                structs_sym_tab,
+            )
+            if not result:
+                logger.error(f"Failed to handle assignment to {var_name}")
+            continue
 
-    if isinstance(target, ast.Name):
-        # NOTE: Simple variable assignment case: x = 5
-        var_name = target.id
-        result = handle_variable_assignment(
-            func,
-            module,
-            builder,
-            var_name,
-            rval,
-            local_sym_tab,
-            map_sym_tab,
-            structs_sym_tab,
-        )
-        if not result:
-            logger.error(f"Failed to handle assignment to {var_name}")
-        return
+        if isinstance(target, ast.Attribute):
+            # NOTE: Struct field assignment case: pkt.field = value
+            handle_struct_field_assignment(
+                func,
+                module,
+                builder,
+                target,
+                rval,
+                local_sym_tab,
+                map_sym_tab,
+                structs_sym_tab,
+            )
+            continue
 
-    if isinstance(target, ast.Attribute):
-        # NOTE: Struct field assignment case: pkt.field = value
-        handle_struct_field_assignment(
-            func,
-            module,
-            builder,
-            target,
-            rval,
-            local_sym_tab,
-            map_sym_tab,
-            structs_sym_tab,
-        )
-        return
-
-    # Unsupported target type
-    logger.error(f"Unsupported assignment target: {ast.dump(target)}")
+        # Unsupported target type
+        logger.error(f"Unsupported assignment target: {ast.dump(target)}")
 
 
 def handle_cond(