Experimental: Add Derive Proc-Macro Caching

Cargo.lock

@@ -3654,6 +3654,7 @@ dependencies = [
  "rustc_lexer",
  "rustc_lint_defs",
  "rustc_macros",
+ "rustc_middle",
  "rustc_parse",
  "rustc_serialize",
  "rustc_session",

compiler/rustc_ast/src/tokenstream.rs

@@ -14,13 +14,15 @@
 //! ownership of the original.
 
 use std::borrow::Cow;
+use std::hash::Hash;
 use std::sync::Arc;
 use std::{cmp, fmt, iter};
 
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync;
 use rustc_macros::{Decodable, Encodable, HashStable_Generic};
-use rustc_serialize::{Decodable, Encodable};
+use rustc_serialize::{Decodable, Encodable, Encoder};
+use rustc_span::def_id::{CrateNum, DefIndex};
 use rustc_span::{DUMMY_SP, Span, SpanDecoder, SpanEncoder, Symbol, sym};
 
 use crate::ast::AttrStyle;
@@ -296,6 +298,96 @@ pub struct AttrsTarget {
 #[derive(Clone, Debug, Default, Encodable, Decodable)]
 pub struct TokenStream(pub(crate) Arc<Vec<TokenTree>>);
 
+struct HashEncoder<H: std::hash::Hasher> {
+    hasher: H,
+}
+
+impl<H: std::hash::Hasher> Encoder for HashEncoder<H> {
+    fn emit_usize(&mut self, v: usize) {
+        self.hasher.write_usize(v)
+    }
+
+    fn emit_u128(&mut self, v: u128) {
+        self.hasher.write_u128(v)
+    }
+
+    fn emit_u64(&mut self, v: u64) {
+        self.hasher.write_u64(v)
+    }
+
+    fn emit_u32(&mut self, v: u32) {
+        self.hasher.write_u32(v)
+    }
+
+    fn emit_u16(&mut self, v: u16) {
+        self.hasher.write_u16(v)
+    }
+
+    fn emit_u8(&mut self, v: u8) {
+        self.hasher.write_u8(v)
+    }
+
+    fn emit_isize(&mut self, v: isize) {
+        self.hasher.write_isize(v)
+    }
+
+    fn emit_i128(&mut self, v: i128) {
+        self.hasher.write_i128(v)
+    }
+
+    fn emit_i64(&mut self, v: i64) {
+        self.hasher.write_i64(v)
+    }
+
+    fn emit_i32(&mut self, v: i32) {
+        self.hasher.write_i32(v)
+    }
+
+    fn emit_i16(&mut self, v: i16) {
+        self.hasher.write_i16(v)
+    }
+
+    fn emit_raw_bytes(&mut self, s: &[u8]) {
+        self.hasher.write(s)
+    }
+}
+
+impl<H: std::hash::Hasher> SpanEncoder for HashEncoder<H> {
+    fn encode_span(&mut self, span: Span) {
+        span.hash(&mut self.hasher)
+    }
+
+    fn encode_symbol(&mut self, symbol: Symbol) {
+        symbol.hash(&mut self.hasher)
+    }
+
+    fn encode_expn_id(&mut self, expn_id: rustc_span::ExpnId) {
+        expn_id.hash(&mut self.hasher)
+    }
+
+    fn encode_syntax_context(&mut self, syntax_context: rustc_span::SyntaxContext) {
+        syntax_context.hash(&mut self.hasher)
+    }
+
+    fn encode_crate_num(&mut self, crate_num: CrateNum) {
+        crate_num.hash(&mut self.hasher)
+    }
+
+    fn encode_def_index(&mut self, def_index: DefIndex) {
+        def_index.hash(&mut self.hasher)
+    }
+
+    fn encode_def_id(&mut self, def_id: rustc_span::def_id::DefId) {
+        def_id.hash(&mut self.hasher)
+    }
+}
+
+impl Hash for TokenStream {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        Encodable::encode(self, &mut HashEncoder { hasher: state });
+    }
+}
+
 /// Indicates whether a token can join with the following token to form a
 /// compound token. Used for conversions to `proc_macro::Spacing`. Also used to
 /// guide pretty-printing, which is where the `JointHidden` value (which isn't

compiler/rustc_expand/Cargo.toml

@@ -21,6 +21,7 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_lexer = { path = "../rustc_lexer" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }
 rustc_macros = { path = "../rustc_macros" }
+rustc_middle = { path = "../rustc_middle" }
 rustc_parse = { path = "../rustc_parse" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }

compiler/rustc_expand/src/expand.rs

@@ -835,17 +835,18 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
             InvocationKind::GlobDelegation { item, of_trait } => {
                 let AssocItemKind::DelegationMac(deleg) = &item.kind else { unreachable!() };
                 let suffixes = match ext {
-                    SyntaxExtensionKind::GlobDelegation(expander) => match expander.expand(self.cx)
-                    {
-                        ExpandResult::Ready(suffixes) => suffixes,
-                        ExpandResult::Retry(()) => {
-                            // Reassemble the original invocation for retrying.
-                            return ExpandResult::Retry(Invocation {
-                                kind: InvocationKind::GlobDelegation { item, of_trait },
-                                ..invoc
-                            });
+                    SyntaxExtensionKind::GlobDelegation(expander) => {
+                        match expander.expand(self.cx) {
+                            ExpandResult::Ready(suffixes) => suffixes,
+                            ExpandResult::Retry(()) => {
+                                // Reassemble the original invocation for retrying.
+                                return ExpandResult::Retry(Invocation {
+                                    kind: InvocationKind::GlobDelegation { item, of_trait },
+                                    ..invoc
+                                });
+                            }
                         }
-                    },
+                    }
                     SyntaxExtensionKind::LegacyBang(..) => {
                         let msg = "expanded a dummy glob delegation";
                         let guar = self.cx.dcx().span_delayed_bug(span, msg);

compiler/rustc_expand/src/lib.rs

@@ -34,4 +34,8 @@ pub mod module;
 #[allow(rustc::untranslatable_diagnostic)]
 pub mod proc_macro;
 
+pub fn provide(providers: &mut rustc_middle::util::Providers) {
+    providers.derive_macro_expansion = proc_macro::provide_derive_macro_expansion;
+}
+
 rustc_fluent_macro::fluent_messages! { "../messages.ftl" }