Revert "Revert "[FRONTEND] do not hold to references unnecessarily (#…

…5402)"" (#3067)

This reverts commit ea006f2.

Closes #3006

python/triton/_utils.py

@@ -22,6 +22,16 @@ def list_list_unflatten(spec: List[int], flat: List[Any]) -> List[List[Any]]:
     return ret
 
 
+def get_iterable_path(iterable, path):
+    from functools import reduce
+    return reduce(lambda a, idx: a[idx], path, iterable)
+
+
+def set_iterable_path(iterable, path, val):
+    prev = iterable if len(path) == 1 else get_iterable_path(iterable, path[:-1])
+    prev[path[-1]] = val
+
+
 def find_paths_if(iterable, pred):
     from .language import core
     is_iterable = lambda x: isinstance(x, (list, tuple, core.tuple, core.tuple_type))
@@ -34,17 +44,17 @@ def _impl(current, path):
                 _impl(item, path + (idx, ))
         elif pred(path, current):
             if len(path) == 1:
-                ret[(path[0], )] = current
+                ret[(path[0], )] = None
             else:
-                ret[tuple(path)] = current
+                ret[tuple(path)] = None
 
     if is_iterable(iterable):
         _impl(iterable, [])
     elif pred(list(), iterable):
-        ret = {tuple(): iterable}
+        ret = {tuple(): None}
     else:
         ret = dict()
-    return ret
+    return list(ret.keys())
 
 
 def parse_list_string(s):

python/triton/compiler/code_generator.py

@@ -14,8 +14,7 @@
 from ..runtime.jit import _normalize_ty, get_jit_fn_file_line
 # ideally we wouldn't need any runtime component
 from ..runtime import JITFunction
-from .._utils import find_paths_if, list_list_flatten, list_list_unflatten
-from functools import reduce
+from .._utils import list_list_flatten, list_list_unflatten, find_paths_if, get_iterable_path, set_iterable_path
 
 from .errors import (CompilationError, CompileTimeAssertionFailure, UnsupportedLanguageConstruct)
 
@@ -196,13 +195,6 @@ def visit_Call(self, node: ast.Call) -> bool:
 
 class ASTFunction:
 
-    def get_path(self, x, path):
-        return reduce(lambda a, idx: a[idx], path, x)
-
-    def set_path(self, x, path, val):
-        prev = x if len(path) == 1 else self.get_path(x, path[:-1])
-        prev[path[-1]] = val
-
     def __init__(self, ret_types, arg_types, constexprs, constants, attrs):
         self.ret_types = ret_types
         self.arg_types = arg_types
@@ -214,8 +206,8 @@ def serialize(self, builder: ir.builder):
         # fill up IR values in template
         # > build function
         is_val = lambda path, _: path not in self.constexprs and _ is not None
-        val_paths = list(find_paths_if(self.arg_types, is_val).keys())
-        arg_types = [self.get_path(self.arg_types, path).to_ir(builder) for path in val_paths]
+        val_paths = list(find_paths_if(self.arg_types, is_val))
+        arg_types = [get_iterable_path(self.arg_types, path).to_ir(builder) for path in val_paths]
         ret_types = [ret_type.to_ir(builder) for ret_type in self.ret_types]
         return builder.get_function_ty(arg_types, ret_types)
 
@@ -228,24 +220,24 @@ def make_template(val):
 
         vals = make_template(self.arg_types)
         is_val = lambda path, _: path not in self.constexprs and _ is not None
-        val_paths = list(find_paths_if(self.arg_types, is_val).keys())
+        val_paths = list(find_paths_if(self.arg_types, is_val))
         # > set attributes
         for attr_path, attr_specs in self.attrs.items():
             for attr_name, attr_val in attr_specs:
                 if attr_path in val_paths:
                     fn.set_arg_attr(val_paths.index(attr_path), attr_name, attr_val)
         for i, path in enumerate(val_paths):
-            ty = self.get_path(self.arg_types, path)
+            ty = get_iterable_path(self.arg_types, path)
             if isinstance(ty, nv_tma_desc_type):
                 fn.set_arg_attr(i, "tt.nv_tma_desc", 1)
         # > add IR values to the template
         for i, path in enumerate(val_paths):
-            ty = self.get_path(self.arg_types, path)
-            self.set_path(vals, path, language.tensor(fn.args(i), ty))
+            ty = get_iterable_path(self.arg_types, path)
+            set_iterable_path(vals, path, language.tensor(fn.args(i), ty))
         # > add constexpr values to the template
         constants = self.constants | self.constexprs
         for path, val in constants.items():
-            self.set_path(vals, path, language.constexpr(val))
+            set_iterable_path(vals, path, language.constexpr(val))
         return vals
 
 
@@ -1140,7 +1132,9 @@ def call_JitFunction(self, fn: JITFunction, args, kwargs):
             if isinstance(arg, (language.dtype, float, int, bool)):
                 args[i] = language.core.constexpr(arg)
         args_cst = find_paths_if(args, lambda _, x: _is_constexpr(x))
-        args_val = find_paths_if(args, lambda _, x: not _is_constexpr(x)).values()
+        args_cst = {path: get_iterable_path(args, path) for path in args_cst}
+        args_path = find_paths_if(args, lambda _, x: not _is_constexpr(x))
+        args_val = [get_iterable_path(args, path) for path in args_path]
         # mangle
         fn_name = mangle_fn(fn.__name__, [arg.type for arg in args_val], args_cst)
         # generate function def if necessary