From e4fb5d80d386dca9c5fa2debc3793319c18c4e8d Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Tue, 26 Dec 2023 23:50:52 +0800
Subject: [PATCH 01/13] remove folding

---
 vyper/codegen/expr.py              | 14 +++++++++++---
 vyper/compiler/phases.py           |  2 +-
 vyper/semantics/analysis/module.py |  2 +-
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index d1687bfc29..3b463a421e 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -70,6 +70,14 @@ class Expr:
     # TODO: Once other refactors are made reevaluate all inline imports
 
     def __init__(self, node, context):
+        # use original node for better diagnostics
+        orig_node = node
+        if isinstance(node, vy_ast.VyperNode):
+            folded_node = node._metadata.get("folded_value")
+            if folded_node:
+                folded_node._metadata["type"] = node._metadata["type"]
+                node = folded_node
+
         self.expr = node
         self.context = context
 
@@ -80,13 +88,13 @@ def __init__(self, node, context):
 
         fn = getattr(self, f"parse_{type(node).__name__}", None)
         if fn is None:
-            raise TypeCheckFailure(f"Invalid statement node: {type(node).__name__}", node)
+            raise TypeCheckFailure(f"Invalid statement node: {type(node).__name__}", orig_node)
 
-        with tag_exceptions(node, fallback_exception_type=CodegenPanic):
+        with tag_exceptions(orig_node, fallback_exception_type=CodegenPanic):
             self.ir_node = fn()
 
         if self.ir_node is None:
-            raise TypeCheckFailure(f"{type(node).__name__} node did not produce IR.\n", node)
+            raise TypeCheckFailure(f"{type(node).__name__} node did not produce IR.\n", orig_node)
 
         self.ir_node.annotation = self.expr.get("node_source_code")
         self.ir_node.source_pos = getpos(self.expr)
diff --git a/vyper/compiler/phases.py b/vyper/compiler/phases.py
index 4982e84b68..184c60c113 100644
--- a/vyper/compiler/phases.py
+++ b/vyper/compiler/phases.py
@@ -280,7 +280,7 @@ def generate_folded_ast(
     symbol_tables = set_data_positions(vyper_module, storage_layout_overrides)
 
     vyper_module_folded = copy.deepcopy(vyper_module)
-    vy_ast.folding.fold(vyper_module_folded)
+    #vy_ast.folding.fold(vyper_module_folded)
 
     return vyper_module_folded, symbol_tables
 
diff --git a/vyper/semantics/analysis/module.py b/vyper/semantics/analysis/module.py
index ffbd2265db..fa2ac73724 100644
--- a/vyper/semantics/analysis/module.py
+++ b/vyper/semantics/analysis/module.py
@@ -495,7 +495,7 @@ def _parse_and_fold_ast(file: FileInput) -> vy_ast.VyperNode:
         resolved_path=str(file.resolved_path),
     )
     vy_ast.validation.validate_literal_nodes(ret)
-    vy_ast.folding.fold(ret)
+    #vy_ast.folding.fold(ret)
 
     return ret
 

From e1e557622bb771e6284eca5b032726eaccec38ce Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Wed, 27 Dec 2023 13:09:55 +0800
Subject: [PATCH 02/13] fix kwarg handling

---
 vyper/builtins/_signatures.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vyper/builtins/_signatures.py b/vyper/builtins/_signatures.py
index 7c8d396f3e..f955296ee0 100644
--- a/vyper/builtins/_signatures.py
+++ b/vyper/builtins/_signatures.py
@@ -34,7 +34,7 @@ def process_arg(arg, expected_arg_type, context):
 
 def process_kwarg(kwarg_node, kwarg_settings, expected_kwarg_type, context):
     if kwarg_settings.require_literal:
-        return kwarg_node.value
+        return kwarg_node.get_folded_value_throwing().value
 
     return process_arg(kwarg_node, expected_kwarg_type, context)
 

From 3a642fbb1179f20e4bc3b110e5beb008c71ec88e Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Wed, 27 Dec 2023 15:12:39 +0800
Subject: [PATCH 03/13] fix kwargs and constant structs

---
 vyper/codegen/expr.py                         |  7 ++++
 .../function_definitions/external_function.py | 40 +++++++++----------
 2 files changed, 27 insertions(+), 20 deletions(-)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index d42ba8babd..25927f1ab0 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -193,6 +193,13 @@ def parse_Name(self):
         # TODO: use self.expr._expr_info
         elif self.expr.id in self.context.globals:
             varinfo = self.context.globals[self.expr.id]
+            if varinfo.modifiability == Modifiability.ALWAYS_CONSTANT:
+                value_node = varinfo.decl_node.value
+                folded_value_node = value_node._metadata.get("folded_value")
+                if folded_value_node is not None:
+                    value_node = folded_value_node
+                return Expr.parse_value_expr(value_node, self.context)
+
             assert varinfo.modifiability == Modifiability.IMMUTABLE, "not an immutable!"
 
             ofst = varinfo.position.offset
diff --git a/vyper/codegen/function_definitions/external_function.py b/vyper/codegen/function_definitions/external_function.py
index f46aa6b2e5..f1a6a1ee1d 100644
--- a/vyper/codegen/function_definitions/external_function.py
+++ b/vyper/codegen/function_definitions/external_function.py
@@ -8,7 +8,7 @@
 from vyper.codegen.stmt import parse_body
 from vyper.evm.address_space import CALLDATA, DATA, MEMORY
 from vyper.semantics.types import TupleT
-from vyper.semantics.types.function import ContractFunctionT
+from vyper.semantics.types.function import ContractFunctionT, KeywordArg, PositionalArg
 
 
 # register function args with the local calling context.
@@ -63,12 +63,14 @@ def _generate_kwarg_handlers(
     #    write default args to memory
     #    goto external_function_common_ir
 
-    def handler_for(calldata_kwargs, original_default_kwargs, folded_default_kwargs):
-        calldata_args = func_t.positional_args + calldata_kwargs
+    def handler_for(calldata_kwargs_info, default_kwargs_info, default_kwargs):
+        calldata_args_info: list[Union[PositionalArg, KeywordArg]] = (
+            func_t.positional_args + calldata_kwargs_info
+        )
         # create a fake type so that get_element_ptr works
-        calldata_args_t = TupleT(list(arg.typ for arg in calldata_args))
+        calldata_args_t = TupleT(list(arg.typ for arg in calldata_args_info))
 
-        abi_sig = func_t.abi_signature_for_kwargs(calldata_kwargs)
+        abi_sig = func_t.abi_signature_for_kwargs(calldata_kwargs_info)
 
         calldata_kwargs_ofst = IRnode(
             4, location=CALLDATA, typ=calldata_args_t, encoding=Encoding.ABI
@@ -82,10 +84,10 @@ def handler_for(calldata_kwargs, original_default_kwargs, folded_default_kwargs)
         calldata_min_size = args_abi_t.min_size() + 4
 
         # TODO optimize make_setter by using
-        # TupleT(list(arg.typ for arg in calldata_kwargs + folded_default_kwargs))
+        # TupleT(list(arg.typ for arg in calldata_kwargs_info + default_kwargs_info))
         # (must ensure memory area is contiguous)
 
-        for i, arg_meta in enumerate(calldata_kwargs):
+        for i, arg_meta in enumerate(calldata_kwargs_info):
             k = func_t.n_positional_args + i
 
             dst = context.lookup_var(arg_meta.name).pos
@@ -98,7 +100,7 @@ def handler_for(calldata_kwargs, original_default_kwargs, folded_default_kwargs)
             copy_arg.source_pos = getpos(arg_meta.ast_source)
             ret.append(copy_arg)
 
-        for x, y in zip(original_default_kwargs, folded_default_kwargs):
+        for x, y in zip(default_kwargs_info, default_kwargs):
             dst = context.lookup_var(x.name).pos
             lhs = IRnode(dst, location=MEMORY, typ=x.typ)
             lhs.source_pos = getpos(y)
@@ -116,26 +118,24 @@ def handler_for(calldata_kwargs, original_default_kwargs, folded_default_kwargs)
 
     ret = {}
 
-    keyword_args = func_t.keyword_args
-    folded_keyword_args = code.args.defaults
+    keyword_args_info = func_t.keyword_args
+    keyword_args = code.args.defaults
 
-    # allocate variable slots in memory
-    for arg in keyword_args:
+    # allocate keyword_args_info slots in memory
+    for arg in keyword_args_info:
         context.new_variable(arg.name, arg.typ, is_mutable=False)
 
-    for i, _ in enumerate(keyword_args):
-        calldata_kwargs = keyword_args[:i]
-        # folded ast
-        original_default_kwargs = keyword_args[i:]
-        # unfolded ast
-        folded_default_kwargs = folded_keyword_args[i:]
+    for i, _ in enumerate(keyword_args_info):
+        calldata_kwargs_info = keyword_args_info[:i]
+        default_kwargs_info: list[KeywordArg] = keyword_args_info[i:]
+        default_kwargs: list[vy_ast.VyperNode] = keyword_args[i:]
 
         sig, calldata_min_size, ir_node = handler_for(
-            calldata_kwargs, original_default_kwargs, folded_default_kwargs
+            calldata_kwargs_info, default_kwargs_info, default_kwargs
         )
         ret[sig] = calldata_min_size, ir_node
 
-    sig, calldata_min_size, ir_node = handler_for(keyword_args, [], [])
+    sig, calldata_min_size, ir_node = handler_for(keyword_args_info, [], [])
 
     ret[sig] = calldata_min_size, ir_node
 

From 27441ec27cff496a67001fb8f6b6e72fdd2e6170 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Wed, 27 Dec 2023 16:46:43 +0800
Subject: [PATCH 04/13] fix list codegen

---
 vyper/codegen/expr.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index 25927f1ab0..28de2a18be 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -720,6 +720,9 @@ def parse_List(self):
         if len(self.expr.elements) == 0:
             return IRnode.from_list("~empty", typ=typ)
 
+        for e in self.expr.elements:
+            if "type" not in e._metadata:
+                e._metadata["type"] = typ.subtype
         multi_ir = [Expr(x, self.context).ir_node for x in self.expr.elements]
 
         return IRnode.from_list(["multi"] + multi_ir, typ=typ)

From 394c9fbf2c73e2a8d4603f3cd3ad7436a912c189 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Wed, 27 Dec 2023 17:21:57 +0800
Subject: [PATCH 05/13] uncatch vyper exception when prefolding call nodes

---
 vyper/semantics/analysis/pre_typecheck.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/vyper/semantics/analysis/pre_typecheck.py b/vyper/semantics/analysis/pre_typecheck.py
index 223407d839..b89c1c6759 100644
--- a/vyper/semantics/analysis/pre_typecheck.py
+++ b/vyper/semantics/analysis/pre_typecheck.py
@@ -1,5 +1,5 @@
 from vyper import ast as vy_ast
-from vyper.exceptions import UnfoldableNode, VyperException
+from vyper.exceptions import UnfoldableNode
 
 
 def get_constants(node: vy_ast.Module) -> dict:
@@ -66,7 +66,7 @@ def prefold(node: vy_ast.VyperNode, constants: dict[str, vy_ast.VyperNode]):
                 try:
                     node._metadata["folded_value"] = call_type.fold(node)
                     return
-                except (UnfoldableNode, VyperException):
+                except UnfoldableNode:
                     pass
 
     if getattr(node, "_is_prefoldable", None):

From 17f01fafcb0089acae2325569d73692a265c1cd8 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 10:45:30 +0800
Subject: [PATCH 06/13] handle const, list and tuples

---
 vyper/ast/nodes.py                | 47 ++++++++++++++++++++++++++++++-
 vyper/codegen/expr.py             |  3 --
 vyper/semantics/analysis/utils.py | 16 +----------
 3 files changed, 47 insertions(+), 19 deletions(-)

diff --git a/vyper/ast/nodes.py b/vyper/ast/nodes.py
index e4e9f37866..cc4929286e 100644
--- a/vyper/ast/nodes.py
+++ b/vyper/ast/nodes.py
@@ -777,7 +777,12 @@ class Constant(ExprNode):
 
     def __init__(self, parent: Optional["VyperNode"] = None, **kwargs: dict):
         super().__init__(parent, **kwargs)
-        self._metadata["folded_value"] = self
+
+    def get_folded_value_throwing(self) -> "VyperNode":
+        return self
+
+    def get_folded_value_maybe(self) -> Optional["VyperNode"]:
+        return self
 
 
 class Num(Constant):
@@ -911,6 +916,18 @@ def s(self):
         return self.value
 
 
+def check_literal(node: VyperNode) -> bool:
+    """
+    Check if the given node is a literal value.
+    """
+    if isinstance(node, Constant):
+        return True
+    elif isinstance(node, (Tuple, List)):
+        return all(check_literal(item) for item in node.elements)
+
+    return False
+
+
 class List(ExprNode):
     __slots__ = ("elements",)
     _is_prefoldable = True
@@ -920,6 +937,18 @@ def fold(self) -> Optional[ExprNode]:
         elements = [e.get_folded_value_throwing() for e in self.elements]
         return type(self).from_node(self, elements=elements)
 
+    def get_folded_value_throwing(self) -> "VyperNode":
+        if check_literal(self):
+            return self
+
+        return super().get_folded_value_throwing()
+
+    def get_folded_value_maybe(self) -> Optional["VyperNode"]:
+        if check_literal(self):
+            return self
+
+        return super().get_folded_value_maybe()
+
 
 class Tuple(ExprNode):
     __slots__ = ("elements",)
@@ -929,6 +958,22 @@ def validate(self):
         if not self.elements:
             raise InvalidLiteral("Cannot have an empty tuple", self)
 
+    def fold(self) -> Optional[ExprNode]:
+        elements = [e.get_folded_value_throwing() for e in self.elements]
+        return type(self).from_node(self, elements=elements)
+
+    def get_folded_value_throwing(self) -> "VyperNode":
+        if check_literal(self):
+            return self
+
+        return super().get_folded_value_throwing()
+
+    def get_folded_value_maybe(self) -> Optional["VyperNode"]:
+        if check_literal(self):
+            return self
+
+        return super().get_folded_value_maybe()
+
 
 class NameConstant(Constant):
     __slots__ = ()
diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index 28de2a18be..25927f1ab0 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -720,9 +720,6 @@ def parse_List(self):
         if len(self.expr.elements) == 0:
             return IRnode.from_list("~empty", typ=typ)
 
-        for e in self.expr.elements:
-            if "type" not in e._metadata:
-                e._metadata["type"] = typ.subtype
         multi_ir = [Expr(x, self.context).ir_node for x in self.expr.elements]
 
         return IRnode.from_list(["multi"] + multi_ir, typ=typ)
diff --git a/vyper/semantics/analysis/utils.py b/vyper/semantics/analysis/utils.py
index 3f91d5f258..dcf81b4d6e 100644
--- a/vyper/semantics/analysis/utils.py
+++ b/vyper/semantics/analysis/utils.py
@@ -624,25 +624,11 @@ def validate_unique_method_ids(functions: List) -> None:
         seen.add(method_id)
 
 
-def _check_literal(node: vy_ast.VyperNode) -> bool:
-    """
-    Check if the given node is a literal value.
-    """
-    if isinstance(node, vy_ast.Constant):
-        return True
-    elif isinstance(node, (vy_ast.Tuple, vy_ast.List)):
-        return all(_check_literal(item) for item in node.elements)
-
-    if node.get_folded_value_maybe():
-        return True
-    return False
-
-
 def check_modifiability(node: vy_ast.VyperNode, modifiability: Modifiability) -> bool:
     """
     Check if the given node is not more modifiable than the given modifiability.
     """
-    if _check_literal(node):
+    if node.get_folded_value_maybe():
         return True
 
     if isinstance(node, (vy_ast.BinOp, vy_ast.Compare)):

From 93a9b4218cd4db82d0ebce0057270a081c913ff3 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 14:56:01 +0800
Subject: [PATCH 07/13] fix tuple

---
 vyper/ast/nodes.py                |  1 +
 vyper/semantics/analysis/local.py | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/vyper/ast/nodes.py b/vyper/ast/nodes.py
index cc4929286e..25da0714ee 100644
--- a/vyper/ast/nodes.py
+++ b/vyper/ast/nodes.py
@@ -952,6 +952,7 @@ def get_folded_value_maybe(self) -> Optional["VyperNode"]:
 
 class Tuple(ExprNode):
     __slots__ = ("elements",)
+    _is_prefoldable = True
     _translated_fields = {"elts": "elements"}
 
     def validate(self):
diff --git a/vyper/semantics/analysis/local.py b/vyper/semantics/analysis/local.py
index 0163547d55..57a9e9afa9 100644
--- a/vyper/semantics/analysis/local.py
+++ b/vyper/semantics/analysis/local.py
@@ -545,13 +545,15 @@ def visit(self, node, typ):
         # can happen.
         super().visit(node, typ)
 
-        folded_value = node.get_folded_value_maybe()
-        if isinstance(folded_value, vy_ast.Constant):
-            validate_expected_type(folded_value, typ)
-
         # annotate
         node._metadata["type"] = typ
 
+        # validate and annotate folded value
+        folded_value = node.get_folded_value_maybe()
+        if folded_value:
+            validate_expected_type(folded_value, typ)
+            folded_value._metadata["type"] = typ
+
     def visit_Attribute(self, node: vy_ast.Attribute, typ: VyperType) -> None:
         _validate_msg_data_attribute(node)
 

From 14d1e093d174c708e7fbd32906e67593e080780c Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 16:17:45 +0800
Subject: [PATCH 08/13] read folded value from metadata

---
 vyper/semantics/analysis/local.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vyper/semantics/analysis/local.py b/vyper/semantics/analysis/local.py
index 57a9e9afa9..417e9e7018 100644
--- a/vyper/semantics/analysis/local.py
+++ b/vyper/semantics/analysis/local.py
@@ -549,7 +549,7 @@ def visit(self, node, typ):
         node._metadata["type"] = typ
 
         # validate and annotate folded value
-        folded_value = node.get_folded_value_maybe()
+        folded_value = node._metadata.get("folded_value")
         if folded_value:
             validate_expected_type(folded_value, typ)
             folded_value._metadata["type"] = typ

From 59f7d3650206d6ef9479043ff6bbef368f7511fe Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 16:53:23 +0800
Subject: [PATCH 09/13] try reverting const amendment

---
 vyper/codegen/expr.py | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index 25927f1ab0..d42ba8babd 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -193,13 +193,6 @@ def parse_Name(self):
         # TODO: use self.expr._expr_info
         elif self.expr.id in self.context.globals:
             varinfo = self.context.globals[self.expr.id]
-            if varinfo.modifiability == Modifiability.ALWAYS_CONSTANT:
-                value_node = varinfo.decl_node.value
-                folded_value_node = value_node._metadata.get("folded_value")
-                if folded_value_node is not None:
-                    value_node = folded_value_node
-                return Expr.parse_value_expr(value_node, self.context)
-
             assert varinfo.modifiability == Modifiability.IMMUTABLE, "not an immutable!"
 
             ofst = varinfo.position.offset

From 1f57495816a54aa14b84ae60be8791235ec661c1 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 17:24:12 +0800
Subject: [PATCH 10/13] revert; assert struct

---
 vyper/codegen/expr.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index d42ba8babd..a2c395631e 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -193,6 +193,14 @@ def parse_Name(self):
         # TODO: use self.expr._expr_info
         elif self.expr.id in self.context.globals:
             varinfo = self.context.globals[self.expr.id]
+            if varinfo.modifiability == Modifiability.ALWAYS_CONSTANT:
+                # non-struct constants should have been dispatched via the `Expr` ctor
+                # using the folded value metadata
+                assert isinstance(varinfo.typ, StructT)
+                value_node = varinfo.decl_node.value
+                value_node = value_node._metadata.get("folded_value", value_node)
+                return Expr.parse_value_expr(value_node, self.context)
+
             assert varinfo.modifiability == Modifiability.IMMUTABLE, "not an immutable!"
 
             ofst = varinfo.position.offset

From 13b341ba347958ab3fcc92e9c70eb916206cb0e1 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 17:31:49 +0800
Subject: [PATCH 11/13] clean up expr codegen ctor

---
 vyper/codegen/expr.py                         |  9 +---
 .../function_definitions/external_function.py | 51 ++++++++-----------
 2 files changed, 24 insertions(+), 36 deletions(-)

diff --git a/vyper/codegen/expr.py b/vyper/codegen/expr.py
index a2c395631e..27266577a0 100644
--- a/vyper/codegen/expr.py
+++ b/vyper/codegen/expr.py
@@ -70,13 +70,8 @@ class Expr:
     # TODO: Once other refactors are made reevaluate all inline imports
 
     def __init__(self, node, context):
-        # use original node for better diagnostics
-        orig_node = node
         if isinstance(node, vy_ast.VyperNode):
-            folded_node = node._metadata.get("folded_value")
-            if folded_node:
-                folded_node._metadata["type"] = node._metadata["type"]
-                node = folded_node
+            node = node._metadata.get("folded_value", node)
 
         self.expr = node
         self.context = context
@@ -89,7 +84,7 @@ def __init__(self, node, context):
             return
 
         fn_name = f"parse_{type(node).__name__}"
-        with tag_exceptions(orig_node, fallback_exception_type=CodegenPanic, note=fn_name):
+        with tag_exceptions(node, fallback_exception_type=CodegenPanic, note=fn_name):
             fn = getattr(self, fn_name)
             self.ir_node = fn()
             assert isinstance(self.ir_node, IRnode), self.ir_node
diff --git a/vyper/codegen/function_definitions/external_function.py b/vyper/codegen/function_definitions/external_function.py
index f1a6a1ee1d..9a66708872 100644
--- a/vyper/codegen/function_definitions/external_function.py
+++ b/vyper/codegen/function_definitions/external_function.py
@@ -1,4 +1,3 @@
-from vyper import ast as vy_ast
 from vyper.codegen.abi_encoder import abi_encoding_matches_vyper
 from vyper.codegen.context import Context, VariableRecord
 from vyper.codegen.core import get_element_ptr, getpos, make_setter, needs_clamp
@@ -8,7 +7,7 @@
 from vyper.codegen.stmt import parse_body
 from vyper.evm.address_space import CALLDATA, DATA, MEMORY
 from vyper.semantics.types import TupleT
-from vyper.semantics.types.function import ContractFunctionT, KeywordArg, PositionalArg
+from vyper.semantics.types.function import ContractFunctionT
 
 
 # register function args with the local calling context.
@@ -51,7 +50,7 @@ def _register_function_args(func_t: ContractFunctionT, context: Context) -> list
 
 
 def _generate_kwarg_handlers(
-    func_t: ContractFunctionT, context: Context, code: vy_ast.FunctionDef
+    func_t: ContractFunctionT, context: Context
 ) -> dict[str, tuple[int, IRnode]]:
     # generate kwarg handlers.
     # since they might come in thru calldata or be default,
@@ -63,14 +62,12 @@ def _generate_kwarg_handlers(
     #    write default args to memory
     #    goto external_function_common_ir
 
-    def handler_for(calldata_kwargs_info, default_kwargs_info, default_kwargs):
-        calldata_args_info: list[Union[PositionalArg, KeywordArg]] = (
-            func_t.positional_args + calldata_kwargs_info
-        )
+    def handler_for(calldata_kwargs, default_kwargs):
+        calldata_args = func_t.positional_args + calldata_kwargs
         # create a fake type so that get_element_ptr works
-        calldata_args_t = TupleT(list(arg.typ for arg in calldata_args_info))
+        calldata_args_t = TupleT(list(arg.typ for arg in calldata_args))
 
-        abi_sig = func_t.abi_signature_for_kwargs(calldata_kwargs_info)
+        abi_sig = func_t.abi_signature_for_kwargs(calldata_kwargs)
 
         calldata_kwargs_ofst = IRnode(
             4, location=CALLDATA, typ=calldata_args_t, encoding=Encoding.ABI
@@ -84,10 +81,10 @@ def handler_for(calldata_kwargs_info, default_kwargs_info, default_kwargs):
         calldata_min_size = args_abi_t.min_size() + 4
 
         # TODO optimize make_setter by using
-        # TupleT(list(arg.typ for arg in calldata_kwargs_info + default_kwargs_info))
+        # TupleT(list(arg.typ for arg in calldata_kwargs + default_kwargs))
         # (must ensure memory area is contiguous)
 
-        for i, arg_meta in enumerate(calldata_kwargs_info):
+        for i, arg_meta in enumerate(calldata_kwargs):
             k = func_t.n_positional_args + i
 
             dst = context.lookup_var(arg_meta.name).pos
@@ -100,15 +97,15 @@ def handler_for(calldata_kwargs_info, default_kwargs_info, default_kwargs):
             copy_arg.source_pos = getpos(arg_meta.ast_source)
             ret.append(copy_arg)
 
-        for x, y in zip(default_kwargs_info, default_kwargs):
+        for x in default_kwargs:
             dst = context.lookup_var(x.name).pos
             lhs = IRnode(dst, location=MEMORY, typ=x.typ)
-            lhs.source_pos = getpos(y)
-            kw_ast_val = y
+            lhs.source_pos = getpos(x.ast_source)
+            kw_ast_val = func_t.default_values[x.name]  # e.g. `3` in x: int = 3
             rhs = Expr(kw_ast_val, context).ir_node
 
             copy_arg = make_setter(lhs, rhs)
-            copy_arg.source_pos = getpos(y)
+            copy_arg.source_pos = getpos(x.ast_source)
             ret.append(copy_arg)
 
         ret.append(["goto", func_t._ir_info.external_function_base_entry_label])
@@ -118,24 +115,20 @@ def handler_for(calldata_kwargs_info, default_kwargs_info, default_kwargs):
 
     ret = {}
 
-    keyword_args_info = func_t.keyword_args
-    keyword_args = code.args.defaults
+    keyword_args = func_t.keyword_args
 
-    # allocate keyword_args_info slots in memory
-    for arg in keyword_args_info:
+    # allocate variable slots in memory
+    for arg in keyword_args:
         context.new_variable(arg.name, arg.typ, is_mutable=False)
 
-    for i, _ in enumerate(keyword_args_info):
-        calldata_kwargs_info = keyword_args_info[:i]
-        default_kwargs_info: list[KeywordArg] = keyword_args_info[i:]
-        default_kwargs: list[vy_ast.VyperNode] = keyword_args[i:]
+    for i, _ in enumerate(keyword_args):
+        calldata_kwargs = keyword_args[:i]
+        default_kwargs = keyword_args[i:]
 
-        sig, calldata_min_size, ir_node = handler_for(
-            calldata_kwargs_info, default_kwargs_info, default_kwargs
-        )
+        sig, calldata_min_size, ir_node = handler_for(calldata_kwargs, default_kwargs)
         ret[sig] = calldata_min_size, ir_node
 
-    sig, calldata_min_size, ir_node = handler_for(keyword_args_info, [], [])
+    sig, calldata_min_size, ir_node = handler_for(keyword_args, [])
 
     ret[sig] = calldata_min_size, ir_node
 
@@ -160,7 +153,7 @@ def generate_ir_for_external_function(code, func_t, context):
     handle_base_args = _register_function_args(func_t, context)
 
     # generate handlers for kwargs and register the variable records
-    kwarg_handlers = _generate_kwarg_handlers(func_t, context, code)
+    kwarg_handlers = _generate_kwarg_handlers(func_t, context)
 
     body = ["seq"]
     # once optional args have been handled,
@@ -192,4 +185,4 @@ def generate_ir_for_external_function(code, func_t, context):
     # besides any kwarg handling
     func_common_ir = IRnode.from_list(["seq", body, exit_], source_pos=getpos(code))
 
-    return kwarg_handlers, func_common_ir
+    return kwarg_handlers, func_common_ir
\ No newline at end of file

From 1709d3a02abfe5279e9510b635d74fe963a852d6 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 17:32:16 +0800
Subject: [PATCH 12/13] relax module node for exception str

---
 vyper/exceptions.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vyper/exceptions.py b/vyper/exceptions.py
index f216069eab..f625a7d3fb 100644
--- a/vyper/exceptions.py
+++ b/vyper/exceptions.py
@@ -108,7 +108,7 @@ def __str__(self):
             if isinstance(node, vy_ast.VyperNode):
                 module_node = node.get_ancestor(vy_ast.Module)
 
-                if module_node.get("path") not in (None, "<unknown>"):
+                if module_node and module_node.get("path") not in (None, "<unknown>"):
                     node_msg = f'{node_msg}contract "{module_node.path}:{node.lineno}", '
 
                 fn_node = node.get_ancestor(vy_ast.FunctionDef)

From fe925d69127da3bb9074ca63694545ef55a6d189 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Thu, 28 Dec 2023 17:32:32 +0800
Subject: [PATCH 13/13] fix lint

---
 vyper/codegen/function_definitions/external_function.py | 2 +-
 vyper/compiler/phases.py                                | 2 +-
 vyper/semantics/analysis/module.py                      | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/vyper/codegen/function_definitions/external_function.py b/vyper/codegen/function_definitions/external_function.py
index 9a66708872..65276469e7 100644
--- a/vyper/codegen/function_definitions/external_function.py
+++ b/vyper/codegen/function_definitions/external_function.py
@@ -185,4 +185,4 @@ def generate_ir_for_external_function(code, func_t, context):
     # besides any kwarg handling
     func_common_ir = IRnode.from_list(["seq", body, exit_], source_pos=getpos(code))
 
-    return kwarg_handlers, func_common_ir
\ No newline at end of file
+    return kwarg_handlers, func_common_ir
diff --git a/vyper/compiler/phases.py b/vyper/compiler/phases.py
index 184c60c113..7407c4f281 100644
--- a/vyper/compiler/phases.py
+++ b/vyper/compiler/phases.py
@@ -280,7 +280,7 @@ def generate_folded_ast(
     symbol_tables = set_data_positions(vyper_module, storage_layout_overrides)
 
     vyper_module_folded = copy.deepcopy(vyper_module)
-    #vy_ast.folding.fold(vyper_module_folded)
+    # vy_ast.folding.fold(vyper_module_folded)
 
     return vyper_module_folded, symbol_tables
 
diff --git a/vyper/semantics/analysis/module.py b/vyper/semantics/analysis/module.py
index fa2ac73724..9d828eaa2d 100644
--- a/vyper/semantics/analysis/module.py
+++ b/vyper/semantics/analysis/module.py
@@ -495,7 +495,7 @@ def _parse_and_fold_ast(file: FileInput) -> vy_ast.VyperNode:
         resolved_path=str(file.resolved_path),
     )
     vy_ast.validation.validate_literal_nodes(ret)
-    #vy_ast.folding.fold(ret)
+    # vy_ast.folding.fold(ret)
 
     return ret