Skip to content

reduce codegen for extern "C" trampoline functions #5586

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Nov 11, 2025
+193 −244
Merged

reduce codegen for extern "C" trampoline functions #5586

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
0c7773b
reduce codegen for extern "C" trampoline functions
davidhewitt Nov 1, 2025
f8451e1
correct cfgs and inlining
davidhewitt Nov 1, 2025
0ef95e5
add doc to warn against function pointer stability
davidhewitt Nov 11, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
82 changes: 13 additions & 69 deletions pyo3-macros-backend/src/method.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -911,76 +911,20 @@ impl<'a> FnSpec<'a> {
FnType::FnStatic => quote! { .flags(#pyo3_path::ffi::METH_STATIC) },
_ => quote! {},
};
match self.convention {
CallingConvention::Noargs => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::noargs(
#python_name,
{
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject
{
unsafe {
#pyo3_path::impl_::trampoline::noargs(
_slf,
_args,
#wrapper
)
}
}
trampoline
},
#doc,
) #flags
},
CallingConvention::Fastcall => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::fastcall_cfunction_with_keywords(
#python_name,
{
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *const *mut #pyo3_path::ffi::PyObject,
_nargs: #pyo3_path::ffi::Py_ssize_t,
_kwnames: *mut #pyo3_path::ffi::PyObject
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::fastcall_with_keywords(
_slf,
_args,
_nargs,
_kwnames,
#wrapper
)
}
trampoline
},
#doc,
) #flags
},
CallingConvention::Varargs => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::cfunction_with_keywords(
#python_name,
{
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *mut #pyo3_path::ffi::PyObject,
_kwargs: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::cfunction_with_keywords(
_slf,
_args,
_kwargs,
#wrapper
)
}
trampoline
},
#doc,
) #flags
},
let trampoline = match self.convention {
CallingConvention::Noargs => Ident::new("noargs", Span::call_site()),
CallingConvention::Fastcall => {
Ident::new("fastcall_cfunction_with_keywords", Span::call_site())
}
CallingConvention::Varargs => Ident::new("cfunction_with_keywords", Span::call_site()),
CallingConvention::TpNew => unreachable!("tp_new cannot get a methoddef"),
};
quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::#trampoline(
#python_name,
#pyo3_path::impl_::trampoline::get_trampoline_function!(#trampoline, #wrapper),
#doc,
) #flags
}
}

Expand Down
49 changes: 4 additions & 45 deletions pyo3-macros-backend/src/pymethod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -376,22 +376,8 @@ pub fn impl_py_method_def_new(
#pyo3_path::ffi::PyType_Slot {
slot: #pyo3_path::ffi::Py_tp_new,
pfunc: {
unsafe extern "C" fn trampoline(
subtype: *mut #pyo3_path::ffi::PyTypeObject,
args: *mut #pyo3_path::ffi::PyObject,
kwargs: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject {

#text_signature_impl

#pyo3_path::impl_::trampoline::newfunc(
subtype,
args,
kwargs,
#cls::#wrapper_ident
)
}
trampoline
#text_signature_impl
#pyo3_path::impl_::trampoline::get_trampoline_function!(newfunc, #cls::#wrapper_ident)
} as #pyo3_path::ffi::newfunc as _
}
};
Expand All @@ -413,22 +399,7 @@ fn impl_call_slot(cls: &syn::Type, mut spec: FnSpec<'_>, ctx: &Ctx) -> Result<Me
let slot_def = quote! {
#pyo3_path::ffi::PyType_Slot {
slot: #pyo3_path::ffi::Py_tp_call,
pfunc: {
unsafe extern "C" fn trampoline(
slf: *mut #pyo3_path::ffi::PyObject,
args: *mut #pyo3_path::ffi::PyObject,
kwargs: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::ternaryfunc(
slf,
args,
kwargs,
#cls::#wrapper_ident
)
}
trampoline
} as #pyo3_path::ffi::ternaryfunc as _
pfunc: #pyo3_path::impl_::trampoline::get_trampoline_function!(ternaryfunc, #cls::#wrapper_ident) as _
}
};
Ok(MethodAndSlotDef {
Expand Down Expand Up @@ -1371,21 +1342,9 @@ impl SlotDef {
}
};
let slot_def = quote! {{
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
#(#arg_idents: #arg_types),*
) -> #ret_ty
{
#pyo3_path::impl_::trampoline:: #func_ty (
_slf,
#(#arg_idents,)*
#cls::#wrapper_ident
)
}

#pyo3_path::ffi::PyType_Slot {
slot: #pyo3_path::ffi::#slot,
pfunc: trampoline as #pyo3_path::ffi::#func_ty as _
pfunc: #pyo3_path::impl_::trampoline::get_trampoline_function!(#func_ty, #cls::#wrapper_ident) as #pyo3_path::ffi::#func_ty as _
}
}};
Ok(MethodAndSlotDef {
Expand Down
Loading
Loading