Rollup merge of rust-lang#140104 - Shourya742:2025-04-21-auto-diff-fails-on-impl-block, r=ZuseZ4

Fix auto diff failing on inherent impl blocks closes: rust-lang#139557 r? ``@ZuseZ4``

Author: ChrisDenton

compiler/rustc_builtin_macros/src/autodiff.rs

@@ -217,14 +217,12 @@ mod llvm_enzyme {
  ast::StmtKind::Item(iitem) => extract_item_info(iitem),
  _ => None,
  },
- Annotatable::AssocItem(assoc_item, Impl { of_trait: false }) => {
- match &assoc_item.kind {
- ast::AssocItemKind::Fn(box ast::Fn { sig, ident, .. }) => {
- Some((assoc_item.vis.clone(), sig.clone(), ident.clone()))
- }
- _ => None,
+ Annotatable::AssocItem(assoc_item, Impl { .. }) => match &assoc_item.kind {
+ ast::AssocItemKind::Fn(box ast::Fn { sig, ident, .. }) => {
+ Some((assoc_item.vis.clone(), sig.clone(), ident.clone()))
  }
- }
+ _ => None,
+ },
  _ => None,
  }) else {
  dcx.emit_err(errors::AutoDiffInvalidApplication { span: item.span() });
@@ -365,7 +363,7 @@ mod llvm_enzyme {
  }
  Annotatable::Item(iitem.clone())
  }
- Annotatable::AssocItem(ref mut assoc_item, i @ Impl { of_trait: false }) => {
+ Annotatable::AssocItem(ref mut assoc_item, i @ Impl { .. }) => {
  if !assoc_item.attrs.iter().any(|a| same_attribute(&a.kind, &attr.kind)) {
  assoc_item.attrs.push(attr);
  }

tests/pretty/autodiff_forward.pp renamed to tests/pretty/autodiff/autodiff_forward.pp

@@ -0,0 +1,41 @@
+#![feature(prelude_import)]
+#![no_std]
+//@ needs-enzyme
+
+#![feature(autodiff)]
+#[prelude_import]
+use ::std::prelude::rust_2015::*;
+#[macro_use]
+extern crate std;
+//@ pretty-mode:expanded
+//@ pretty-compare-only
+//@ pp-exact:inherent_impl.pp
+
+use std::autodiff::autodiff;
+
+struct Foo {
+ a: f64,
+}
+
+trait MyTrait {
+ fn f(&self, x: f64)
+ -> f64;
+ fn df(&self, x: f64, seed: f64)
+ -> (f64, f64);
+}
+
+impl MyTrait for Foo {
+ #[rustc_autodiff]
+ #[inline(never)]
+ fn f(&self, x: f64) -> f64 {
+ self.a * 0.25 * (x * x - 1.0 - 2.0 * x.ln())
+ }
+ #[rustc_autodiff(Reverse, 1, Const, Active, Active)]
+ #[inline(never)]
+ fn df(&self, x: f64, dret: f64) -> (f64, f64) {
+ unsafe { asm!("NOP", options(pure, nomem)); };
+ ::core::hint::black_box(self.f(x));
+ ::core::hint::black_box((dret,));
+ ::core::hint::black_box((self.f(x), f64::default()))
+ }
+}

tests/pretty/autodiff_forward.rs renamed to tests/pretty/autodiff/autodiff_forward.rs

@@ -0,0 +1,24 @@
+//@ needs-enzyme
+
+#![feature(autodiff)]
+//@ pretty-mode:expanded
+//@ pretty-compare-only
+//@ pp-exact:inherent_impl.pp
+
+use std::autodiff::autodiff;
+
+struct Foo {
+ a: f64,
+}
+
+trait MyTrait {
+ fn f(&self, x: f64) -> f64;
+ fn df(&self, x: f64, seed: f64) -> (f64, f64);
+}
+
+impl MyTrait for Foo {
+ #[autodiff(df, Reverse, Const, Active, Active)]
+ fn f(&self, x: f64) -> f64 {
+ self.a * 0.25 * (x * x - 1.0 - 2.0 * x.ln())
+ }
+}