[perf] Use Blake2 for the type-id hash

Cargo.lock

@@ -275,6 +275,15 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
+[[package]]
+name = "blake2"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46502ad458c9a52b69d4d4d32775c788b7a1b85e8bc9d482d92250fc0e3f8efe"
+dependencies = [
+ "digest",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -1017,6 +1026,7 @@ checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
 dependencies = [
  "block-buffer",
  "crypto-common",
+ "subtle",
 ]
 
 [[package]]
@@ -3227,8 +3237,10 @@ checksum = "5be1bdc7edf596692617627bbfeaba522131b18e06ca4df2b6b689e3c5d5ce84"
 [[package]]
 name = "rustc-stable-hash"
 version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5c9f15eec8235d7cb775ee6f81891db79b98fd54ba1ad8fae565b88ef1ae4e2"
+source = "git+https://github.com/Urgau/rustc-stable-hash.git?rev=543696a#543696a0b6299c4cc8a8c9c30651e5cc0056655a"
+dependencies = [
+ "blake2",
+]
 
 [[package]]
 name = "rustc_abi"
@@ -5067,6 +5079,12 @@ dependencies = [
  "syn 1.0.109",
 ]
 
+[[package]]
+name = "subtle"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
+
 [[package]]
 name = "suggest-tests"
 version = "0.1.0"

compiler/rustc_ast/src/ast.rs

@@ -23,7 +23,7 @@ use std::{cmp, fmt, mem};
 
 pub use rustc_ast_ir::{Movability, Mutability};
 use rustc_data_structures::packed::Pu128;
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_data_structures::sync::Lrc;
 use rustc_macros::{Decodable, Encodable, HashStable_Generic};
@@ -105,7 +105,7 @@ impl PartialEq<Symbol> for Path {
 }
 
 impl<CTX: rustc_span::HashStableContext> HashStable<CTX> for Path {
-    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, hcx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         self.segments.len().hash_stable(hcx, hasher);
         for segment in &self.segments {
             segment.ident.hash_stable(hcx, hasher);
@@ -1723,7 +1723,7 @@ impl<CTX> HashStable<CTX> for AttrArgs
 where
     CTX: crate::HashStableContext,
 {
-    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, ctx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         mem::discriminant(self).hash_stable(ctx, hasher);
         match self {
             AttrArgs::Empty => {}
@@ -1759,7 +1759,7 @@ impl<CTX> HashStable<CTX> for DelimArgs
 where
     CTX: crate::HashStableContext,
 {
-    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, ctx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         let DelimArgs { dspan, delim, tokens } = self;
         dspan.hash_stable(ctx, hasher);
         delim.hash_stable(ctx, hasher);

compiler/rustc_ast/src/lib.rs

@@ -43,7 +43,7 @@ pub mod token;
 pub mod tokenstream;
 pub mod visit;
 
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 
 pub use self::ast::*;
 pub use self::ast_traits::{AstDeref, AstNodeWrapper, HasAttrs, HasNodeId, HasTokens};
@@ -52,11 +52,19 @@ pub use self::ast_traits::{AstDeref, AstNodeWrapper, HasAttrs, HasNodeId, HasTok
 /// This is a hack to allow using the `HashStable_Generic` derive macro
 /// instead of implementing everything in `rustc_middle`.
 pub trait HashStableContext: rustc_span::HashStableContext {
-    fn hash_attr(&mut self, _: &ast::Attribute, hasher: &mut StableHasher);
+    fn hash_attr<H: ExtendedHasher>(
+        &mut self,
+        _: &ast::Attribute,
+        hasher: &mut GenericStableHasher<H>,
+    );
 }
 
 impl<AstCtx: crate::HashStableContext> HashStable<AstCtx> for ast::Attribute {
-    fn hash_stable(&self, hcx: &mut AstCtx, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(
+        &self,
+        hcx: &mut AstCtx,
+        hasher: &mut GenericStableHasher<H>,
+    ) {
         hcx.hash_attr(self, hasher)
     }
 }

compiler/rustc_ast/src/ptr.rs

@@ -21,7 +21,7 @@ use std::fmt::{self, Debug, Display};
 use std::ops::{Deref, DerefMut};
 use std::{slice, vec};
 
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 /// An owned smart pointer.
 ///
@@ -203,7 +203,7 @@ impl<CTX, T> HashStable<CTX> for P<T>
 where
     T: ?Sized + HashStable<CTX>,
 {
-    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, hcx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         (**self).hash_stable(hcx, hasher);
     }
 }

compiler/rustc_ast/src/token.rs

@@ -1,7 +1,7 @@
 use std::borrow::Cow;
 use std::fmt;
 
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 use rustc_data_structures::sync::Lrc;
 use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_span::edition::Edition;
@@ -1055,7 +1055,7 @@ impl<CTX> HashStable<CTX> for Nonterminal
 where
     CTX: crate::HashStableContext,
 {
-    fn hash_stable(&self, _hcx: &mut CTX, _hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, _hcx: &mut CTX, _hasher: &mut GenericStableHasher<H>) {
         panic!("interpolated tokens should not be present in the HIR")
     }
 }

compiler/rustc_ast/src/tokenstream.rs

@@ -16,7 +16,7 @@
 use std::borrow::Cow;
 use std::{cmp, fmt, iter};
 
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 use rustc_data_structures::sync::{self, Lrc};
 use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 use rustc_serialize::{Decodable, Encodable};
@@ -99,7 +99,7 @@ impl<CTX> HashStable<CTX> for TokenStream
 where
     CTX: crate::HashStableContext,
 {
-    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, hcx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         for sub_tt in self.trees() {
             sub_tt.hash_stable(hcx, hasher);
         }
@@ -151,7 +151,7 @@ impl<D: SpanDecoder> Decodable<D> for LazyAttrTokenStream {
 }
 
 impl<CTX> HashStable<CTX> for LazyAttrTokenStream {
-    fn hash_stable(&self, _hcx: &mut CTX, _hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, _hcx: &mut CTX, _hasher: &mut GenericStableHasher<H>) {
         panic!("Attempted to compute stable hash for LazyAttrTokenStream");
     }
 }

compiler/rustc_codegen_cranelift/src/driver/aot.rs

@@ -15,7 +15,7 @@ use rustc_codegen_ssa::{
     errors as ssa_errors, CodegenResults, CompiledModule, CrateInfo, ModuleKind,
 };
 use rustc_data_structures::profiling::SelfProfilerRef;
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 use rustc_data_structures::sync::{par_map, IntoDynSyncSend};
 use rustc_metadata::fs::copy_to_stdout;
 use rustc_metadata::EncodedMetadata;
@@ -43,7 +43,7 @@ enum OngoingModuleCodegen {
 }
 
 impl<HCX> HashStable<HCX> for OngoingModuleCodegen {
-    fn hash_stable(&self, _: &mut HCX, _: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, _: &mut HCX, _: &mut GenericStableHasher<H>) {
         // do nothing
     }
 }

compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs

@@ -2,7 +2,7 @@ use std::cell::RefCell;
 
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_data_structures::stable_hasher::{HashStable, StableBlake2sHasher256};
 use rustc_macros::HashStable;
 use rustc_middle::bug;
 use rustc_middle::ty::{ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
@@ -94,7 +94,7 @@ impl<'tcx> UniqueTypeId<'tcx> {
     ///
     /// Right now this takes the form of a hex-encoded opaque hash value.
     pub fn generate_unique_id_string(self, tcx: TyCtxt<'tcx>) -> String {
-        let mut hasher = StableHasher::new();
+        let mut hasher = StableBlake2sHasher256::new();
         tcx.with_stable_hashing_context(|mut hcx| {
             hcx.while_hashing_spans(false, |hcx| self.hash_stable(hcx, &mut hasher))
         });

compiler/rustc_codegen_ssa/src/common.rs

@@ -107,12 +107,12 @@ pub enum TypeKind {
 //            for now we content ourselves with providing a no-op HashStable
 //            implementation for CGUs.
 mod temp_stable_hash_impls {
-    use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+    use rustc_data_structures::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 
     use crate::ModuleCodegen;
 
     impl<HCX, M> HashStable<HCX> for ModuleCodegen<M> {
-        fn hash_stable(&self, _: &mut HCX, _: &mut StableHasher) {
+        fn hash_stable<H: ExtendedHasher>(&self, _: &mut HCX, _: &mut GenericStableHasher<H>) {
             // do nothing
         }
     }

compiler/rustc_data_structures/Cargo.toml

@@ -15,7 +15,7 @@ jobserver_crate = { version = "0.1.28", package = "jobserver" }
 measureme = "11"
 rustc-hash = "1.1.0"
 rustc-rayon = { version = "0.5.0", optional = true }
-rustc-stable-hash = { version = "0.1.0", features = ["nightly"] }
+rustc-stable-hash = { git = "https://github.com/Urgau/rustc-stable-hash.git", rev = "543696a", features = ["nightly"] }
 rustc_arena = { path = "../rustc_arena" }
 rustc_graphviz = { path = "../rustc_graphviz" }
 rustc_index = { path = "../rustc_index", package = "rustc_index" }

compiler/rustc_data_structures/src/fingerprint.rs

@@ -1,6 +1,7 @@
 use std::hash::{Hash, Hasher};
 
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_stable_hash::hashers::Blake2s256Hash;
 
 use crate::stable_hasher::{
     impl_stable_traits_for_trivial_type, FromStableHash, Hash64, StableHasherHash,
@@ -157,15 +158,27 @@ impl FingerprintHasher for crate::unhash::Unhasher {
     }
 }
 
-impl FromStableHash for Fingerprint {
-    type Hash = StableHasherHash;
-
+impl FromStableHash<StableHasherHash> for Fingerprint {
     #[inline]
-    fn from(StableHasherHash([_0, _1]): Self::Hash) -> Self {
+    fn from(StableHasherHash([_0, _1]): StableHasherHash) -> Self {
         Fingerprint(_0, _1)
     }
 }
 
+impl FromStableHash<Blake2s256Hash> for Fingerprint {
+    #[inline]
+    fn from(Blake2s256Hash(bytes): Blake2s256Hash) -> Self {
+        let p0 = u64::from_le_bytes(bytes[0..8].try_into().unwrap());
+        let p1 = u64::from_le_bytes(bytes[8..16].try_into().unwrap());
+        let p2 = u64::from_le_bytes(bytes[16..24].try_into().unwrap());
+        let p3 = u64::from_le_bytes(bytes[24..32].try_into().unwrap());
+
+        // See https://stackoverflow.com/a/27952689 on why this function is
+        // implemented this way.
+        Fingerprint(p0.wrapping_mul(3).wrapping_add(p1), p2.wrapping_mul(3).wrapping_add(p3))
+    }
+}
+
 impl_stable_traits_for_trivial_type!(Fingerprint);
 
 impl<E: Encoder> Encodable<E> for Fingerprint {

compiler/rustc_data_structures/src/hashes.rs

@@ -15,6 +15,7 @@ use std::fmt;
 use std::ops::BitXorAssign;
 
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_stable_hash::hashers::Blake2s256Hash;
 
 use crate::stable_hasher::{FromStableHash, StableHasherHash};
 
@@ -58,11 +59,9 @@ impl<D: Decoder> Decodable<D> for Hash64 {
     }
 }
 
-impl FromStableHash for Hash64 {
-    type Hash = StableHasherHash;
-
+impl FromStableHash<StableHasherHash> for Hash64 {
     #[inline]
-    fn from(StableHasherHash([_0, __1]): Self::Hash) -> Self {
+    fn from(StableHasherHash([_0, __1]): StableHasherHash) -> Self {
         Self { inner: _0 }
     }
 }
@@ -125,15 +124,25 @@ impl<D: Decoder> Decodable<D> for Hash128 {
     }
 }
 
-impl FromStableHash for Hash128 {
-    type Hash = StableHasherHash;
-
+impl FromStableHash<StableHasherHash> for Hash128 {
     #[inline]
-    fn from(StableHasherHash([_0, _1]): Self::Hash) -> Self {
+    fn from(StableHasherHash([_0, _1]): StableHasherHash) -> Self {
         Self { inner: u128::from(_0) | (u128::from(_1) << 64) }
     }
 }
 
+impl FromStableHash<Blake2s256Hash> for Hash128 {
+    #[inline]
+    fn from(Blake2s256Hash(bytes): Blake2s256Hash) -> Self {
+        let p0 = u128::from_le_bytes(bytes[0..16].try_into().unwrap());
+        let p1 = u128::from_le_bytes(bytes[16..32].try_into().unwrap());
+
+        // See https://stackoverflow.com/a/27952689 on why this function is
+        // implemented this way.
+        Self { inner: p0.wrapping_mul(3).wrapping_add(p1) }
+    }
+}
+
 impl fmt::Debug for Hash128 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.inner.fmt(f)

compiler/rustc_data_structures/src/intern.rs

@@ -4,7 +4,7 @@ use std::hash::{Hash, Hasher};
 use std::ops::Deref;
 use std::ptr;
 
-use crate::stable_hasher::{HashStable, StableHasher};
+use crate::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 
 mod private {
     #[derive(Clone, Copy, Debug)]
@@ -104,7 +104,7 @@ impl<T, CTX> HashStable<CTX> for Interned<'_, T>
 where
     T: HashStable<CTX>,
 {
-    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, hcx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         self.0.hash_stable(hcx, hasher);
     }
 }

compiler/rustc_data_structures/src/packed.rs

@@ -3,7 +3,7 @@ use std::fmt;
 
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 
-use crate::stable_hasher::{HashStable, StableHasher};
+use crate::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable};
 
 /// A packed 128-bit integer. Useful for reducing the size of structures in
 /// some cases.
@@ -55,7 +55,7 @@ impl fmt::UpperHex for Pu128 {
 
 impl<CTX> HashStable<CTX> for Pu128 {
     #[inline]
-    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, ctx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         { self.0 }.hash_stable(ctx, hasher)
     }
 }

compiler/rustc_data_structures/src/sorted_map.rs

@@ -5,7 +5,7 @@ use std::ops::{Bound, Index, IndexMut, RangeBounds};
 
 use rustc_macros::{Decodable_Generic, Encodable_Generic};
 
-use crate::stable_hasher::{HashStable, StableHasher, StableOrd};
+use crate::stable_hasher::{ExtendedHasher, GenericStableHasher, HashStable, StableOrd};
 
 mod index_map;
 
@@ -311,7 +311,7 @@ impl<K: Ord, V> FromIterator<(K, V)> for SortedMap<K, V> {
 
 impl<K: HashStable<CTX> + StableOrd, V: HashStable<CTX>, CTX> HashStable<CTX> for SortedMap<K, V> {
     #[inline]
-    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+    fn hash_stable<H: ExtendedHasher>(&self, ctx: &mut CTX, hasher: &mut GenericStableHasher<H>) {
         self.data.hash_stable(ctx, hasher);
     }
 }