Faster-to-compile pathway for raising exceptions.

Author: braxtonmckee

typed_python/_runtime.cpp

@@ -2754,15 +2754,16 @@ extern "C" {
     }
 
     // set the python exception state, but don't actually throw.
-    void np_raise_exception_fastpath(const char* message, const char* exceptionTypeName) {
+    void np_raise_exception_str(PythonObjectOfType::layout_type* exceptionType, const char* message) {
         PyEnsureGilAcquired getTheGil;
 
-        PyObject* excType = PyObject_GetAttrString(builtinsModule(), exceptionTypeName);
-        if (!excType) {
-            return;
+        if (message) {
+            PyErr_SetString(exceptionType->pyObj, message);
+        } else {
+            PyErr_SetNone(exceptionType->pyObj);
         }
 
-        PyErr_SetString(excType, message);
+        throw PythonExceptionSet();
     }
 
     BytesType::layout* np_serialize_no_context(instance_ptr data, Type* type) {

typed_python/compiler/expression_conversion_context.py

@@ -1286,33 +1286,44 @@ def pushException(self, excType, *args, **kwargs):
         Returns:
             None
         """
+        if len(args) == 0 and isinstance(excType, type):
+            self.pushEffect(
+                runtime_functions.np_raise_exception_str.call(
+                    self.constantPyObject(excType).nonref_expr.cast(native_ast.VoidPtr),
+                    native_ast.UInt8.pointer().zero(),
+                )
+            )
+            return None
+
         if len(args) == 1 and isinstance(args[0], str) and isinstance(excType, type):
             # this is the most common pathway
-            if id(excType) in builtinValueIdToNameAndValue:
-                self.pushEffect(
-                    runtime_functions.raise_exception_fastpath.call(
-                        native_ast.const_utf8_cstr(args[0]),
-                        native_ast.const_utf8_cstr(builtinValueIdToNameAndValue[id(excType)][0])
-                    )
+            self.pushEffect(
+                runtime_functions.np_raise_exception_str.call(
+                    self.constantPyObject(excType).nonref_expr.cast(native_ast.VoidPtr),
+                    native_ast.const_utf8_cstr(args[0]),
                 )
-                self.pushEffect(
-                    native_ast.Expression.Throw(
-                        expr=native_ast.Expression.Constant(
-                            val=native_ast.Constant.NullPointer(value_type=native_ast.UInt8.pointer())
-                        )
-                    )
-                )
-                return None
+            )
+            return None
 
         def toTyped(x):
             if isinstance(x, TypedExpression):
                 return x
             return self.constant(x)
 
+        origExcType = excType
         excType = toTyped(excType)
         args = [toTyped(x) for x in args]
         kwargs = {k: toTyped(v) for k, v in kwargs.items()}
 
+        if len(args) == 1 and isinstance(args[0].constantValue, str) and isinstance(origExcType, type):
+            self.pushEffect(
+                runtime_functions.np_raise_exception_str.call(
+                    self.constantPyObject(origExcType).nonref_expr.cast(native_ast.VoidPtr),
+                    native_ast.const_utf8_cstr(args[0].constantValue),
+                )
+            )
+            return None
+
         if excType is None:
             return None
 

typed_python/compiler/tests/exception_handling_test.py

@@ -220,3 +220,25 @@ def catcher(toRaise):
 
     with pytest.raises(RuntimeError):
         catcher(RuntimeError)
+
+
+def test_convert_assert():
+    @Entrypoint
+    def assertIt(x):
+        assert x
+
+    assertIt(True)
+
+    with pytest.raises(AssertionError):
+        assertIt(False)
+
+
+def test_convert_assert_str():
+    @Entrypoint
+    def assertIt(x):
+        assert x, "failed"
+
+    assertIt(True)
+
+    with pytest.raises(AssertionError):
+        assertIt(False)

typed_python/compiler/type_wrappers/runtime_functions.py

@@ -1163,11 +1163,12 @@ def unaryPyobjCallTarget(name, retType=Void.pointer()):
 )
 
 # sets the python exception state to an exception of type
-raise_exception_fastpath = externalCallTarget(
-    "np_raise_exception_fastpath",
+np_raise_exception_str = externalCallTarget(
+    "np_raise_exception_str",
     Void,
+    Void.pointer(),
     UInt8Ptr,
-    UInt8Ptr
+    canThrow=True
 )
 
 raiseAttributeError = externalCallTarget(