chore: improve exception handling in IR generation (vyperlang#3705)

QOL improvement - improve unannotated exceptions that happen during IR
generation to include source info.

vyper/codegen/expr.py

@@ -26,13 +26,15 @@
 from vyper.evm.address_space import DATA, IMMUTABLES, MEMORY, STORAGE, TRANSIENT
 from vyper.evm.opcodes import version_check
 from vyper.exceptions import (
+    CodegenPanic,
     CompilerPanic,
     EvmVersionException,
     StructureException,
     TypeCheckFailure,
     TypeMismatch,
     UnimplementedException,
     VyperException,
+    tag_exceptions,
 )
 from vyper.semantics.types import (
     AddressT,
@@ -79,7 +81,9 @@ def __init__(self, node, context):
         if fn is None:
             raise TypeCheckFailure(f"Invalid statement node: {type(node).__name__}", node)
 
-        self.ir_node = fn()
+        with tag_exceptions(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)
 

vyper/codegen/stmt.py

@@ -24,7 +24,13 @@
 from vyper.codegen.expr import Expr
 from vyper.codegen.return_ import make_return_stmt
 from vyper.evm.address_space import MEMORY, STORAGE
-from vyper.exceptions import CompilerPanic, StructureException, TypeCheckFailure
+from vyper.exceptions import (
+    CodegenPanic,
+    CompilerPanic,
+    StructureException,
+    TypeCheckFailure,
+    tag_exceptions,
+)
 from vyper.semantics.types import DArrayT, MemberFunctionT
 from vyper.semantics.types.function import ContractFunctionT
 from vyper.semantics.types.shortcuts import INT256_T, UINT256_T
@@ -39,7 +45,8 @@ def __init__(self, node: vy_ast.VyperNode, context: Context) -> None:
             raise TypeCheckFailure(f"Invalid statement node: {type(node).__name__}")
 
         with context.internal_memory_scope():
-            self.ir_node = fn()
+            with tag_exceptions(node, fallback_exception_type=CodegenPanic):
+                self.ir_node = fn()
 
         if self.ir_node is None:
             raise TypeCheckFailure("Statement node did not produce IR")

vyper/exceptions.py

@@ -1,3 +1,4 @@
+import contextlib
 import copy
 import textwrap
 import types
@@ -322,8 +323,9 @@ class VyperInternalException(_BaseVyperException):
 
     def __str__(self):
         return (
-            f"{self.message}\n\nThis is an unhandled internal compiler error. "
-            "Please create an issue on Github to notify the developers.\n"
+            f"{super().__str__()}\n\n"
+            "This is an unhandled internal compiler error. "
+            "Please create an issue on Github to notify the developers!\n"
             "https://github.com/vyperlang/vyper/issues/new?template=bug.md"
         )
 
@@ -354,3 +356,17 @@ class TypeCheckFailure(VyperInternalException):
 
 class InvalidABIType(VyperInternalException):
     """An internal routine constructed an invalid ABI type"""
+
+
+@contextlib.contextmanager
+def tag_exceptions(
+    node, fallback_exception_type=CompilerPanic, fallback_message="unhandled exception"
+):
+    try:
+        yield
+    except _BaseVyperException as e:
+        if not e.annotations and not e.lineno:
+            raise e.with_annotation(node) from None
+        raise e from None
+    except Exception as e:
+        raise fallback_exception_type(fallback_message, node) from e

vyper/semantics/analysis/common.py

@@ -1,17 +1,6 @@
-import contextlib
 from typing import Tuple
 
-from vyper.exceptions import StructureException, VyperException
-
-
-@contextlib.contextmanager
-def tag_exceptions(node):
-    try:
-        yield
-    except VyperException as e:
-        if not e.annotations and not e.lineno:
-            raise e.with_annotation(node) from None
-        raise e from None
+from vyper.exceptions import StructureException, tag_exceptions
 
 
 class VyperNodeVisitorBase: